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Sample records for method schooler criticized

  1. Teaching fluid mechanics to high schoolers: methods, challenges, and outcome

    Science.gov (United States)

    Manikantan, Harishankar

    2017-11-01

    This talk will summarize the goals, methods, and both short- and long-term feedback from two high-school-level courses in fluid mechanics involving 43 students and cumulatively spanning over 100 hours of instruction. The goals of these courses were twofold: (a) to spark an interest in science and engineering and attract a more diverse demographic into college-level STEM programs; and (b) to train students in a `college-like' method of approaching the physics of common phenomena, with fluid mechanics as the context. The methods of instruction included classes revolving around the idea of dispelling misconceptions, group activities, `challenge' rounds and mock design projects to use fluid mechanics phenomena to achieve a specified goal, and simple hands-on experiments. The feedback during instruction was overwhelmingly positive, particularly in terms of a changing and favorable attitude towards math and engineering. Long after the program, a visible impact lies in a diverse group of students acknowledging that the course had a positive effect in their decision to choose an engineering or science major in a four-year college.

  2. 'I felt a little bubbly in my tummy': eliciting pre-schoolers' accounts of their health visit using a computer-assisted interview method.

    Science.gov (United States)

    Bokström, P; Fängström, K; Calam, R; Lucas, S; Sarkadi, A

    2016-01-01

    In the health care services, children's rights to participate in all matters that concern them are considered important. However, in practice this can be challenging with young children. In My Shoes (IMS) is a computer-assisted interview tool developed to help children talk about their experiences. The aim of the study was to evaluate the IMS' ability to elicit pre-schoolers' subjective experiences and accurate accounts of a routine health visit as well as the children's engagement in the interview process. Interviews were conducted with 23 children aged 4-5 years, 2-4 weeks after their health visit. The interviews were transcribed verbatim and analysed using a method inspired by Content Analysis to evaluate IMS's ability to elicit accounts about subjective experiences. Accurate accounts were assessed by comparing the transcribed interviews with the filmed visits at the child health centre. The children's engagement was defined by the completion and length of the interviews, and the children's interaction with the software. All children gave accounts about their subjective experiences, such as their emotional state during the visit, available toys or rewards they received. All children related to the correct event, they all named at least one person who was present and 87% correctly named at least one examination procedure. The majority of children (91%) completed the interview, which lasted 17-39 min (M = 24), and 96% interacted with the IMS software. IMS was feasible to help children describe their health care experiences, in both detail and depth. The children interacted with the software and maintained their interest for an extended period of time. © 2015 John Wiley & Sons Ltd.

  3. Alternative methods in criticality

    International Nuclear Information System (INIS)

    Pedicini, J.M.

    1982-01-01

    In this thesis two new methods of calculating the criticality of a nuclear system are introduced and verified. Most methods of determining the criticality of a nuclear system depend implicitly upon knowledge of the angular flux, net currents, or moments of the angular flux, on the system surface in order to know the leakage. For small systems, leakage is the predominant element in criticality calculations. Unfortunately, in these methods the least accurate fluxes, currents, or moments are those occurring near system surfaces or interfaces. This is due to a mathematical inability to satisfy rigorously with a finite order angular polynomial expansion or angular difference technique the physical boundary conditions which occur on these surfaces. Consequently, one must accept large computational effort or less precise criticality calculations. The methods introduced in this thesis, including a direct leakage operator and an indirect multiple scattering leakage operator, obviate the need to know angular fluxes accurately at system boundaries. Instead, the system wide scalar flux, an integral quantity which is substantially easier to obtain with good precision is sufficient to obtain production, absorption, scattering, and leakage rates

  4. Alternative methods in criticality

    International Nuclear Information System (INIS)

    Pedicini, J.M.

    1982-01-01

    Two new methods of calculating the criticality of a nuclear system are introduced and verified. Most methods of determining the criticality of a nuclear system depend implicitly upon knowledge of the angular flux, net currents, or moments of the angular flux, on the system surface in order to know the leakage. For small systems, leakage is the predominant element in criticality calculations. Unfortunately, in these methods the least accurate fluxes, currents, or moments are those occuring near system surfaces or interfaces. This is due to a mathematical inability to satisfy rigorously with a finite order angular polynomial expansion or angular difference technique the physical boundary conditions which occur on these surfaces. Consequently, one must accept large computational effort or less precise criticality calculations. The methods introduced in this thesis, including a direct leakage operator and an indirect multiple scattering leakage operator, obviate the need to know angular fluxes accurately at system boundaries. Instead, the system wide scalar flux, an integral quantity which is substantially easier to obtain with good precision, is sufficient to obtain production, absorption, scattering, and leakage rates

  5. Pragmatics in pre-schoolers with language impairments.

    Science.gov (United States)

    Geurts, Hilde; Embrechts, Mariëtte

    2010-01-01

    Pragmatic assessment methods are very diverse and differ in informant type. Some rely on parents, others on teachers/professionals and some directly test pragmatic abilities in the children themselves. A widely used pragmatic parent questionnaire is the Children's Communication Checklist--2 (CCC-2). However, it is not known how scores on the CCC-2 relate to direct measures of pragmatics. The aim of the current study is determine whether children's language patterns on pragmatics obtained with a parent questionnaire were converging with findings when the children were directly tested with a pragmatic test. The CCC-2 and the Nijmegen Pragmatics Test (NPT) were applied to 24 pre-schoolers (aged 4-7 years) with various language impairments and 33 age-matched typically developing pre-schoolers. Both pragmatic language instruments clearly differentiated between pre-schoolers with language impairments and those without language impairments. However, the obtained correlations between the different measures were low to moderate. The specificity of each of the instruments was sufficient, but the sensitivity was generally poor. The instruments were not always converging, but when the instruments did converge the obtained results were valid. However, the obtained high specificity and relatively low sensitivity values for each of the instruments showed that better cut-off scores are needed. When only one of the instruments indicated the absence or presence of language impairments, one needs to be careful in concluding whether or not there are indeed language impairments.

  6. Does maternal psychopathology increase the risk of pre-schooler obesity? A systematic review.

    Science.gov (United States)

    Benton, Pree M; Skouteris, Helen; Hayden, Melissa

    2015-04-01

    The preschool years may be a critical period for child obesity onset; however, literature examining obesity risk factors to date has largely focused on school-aged children. Several links have been made between maternal depression and childhood obesity risks; however, other types of maternal psychopathology have been widely neglected. The aim of the present review was to systematically identify articles that examined relationships between maternal psychopathology variables, including depressive and anxiety symptoms, self-esteem and body dissatisfaction, and risks for pre-schooler obesity, including weight outcomes, physical activity and sedentary behaviour levels, and nutrition/diet variables. Twenty articles meeting review criteria were identified. Results showed positive associations between maternal depressive symptoms and increased risks for pre-schooler obesity in the majority of studies. Results were inconsistent depending on the time at which depression was measured (i.e., antenatal, postnatal, in isolation or longitudinally). Anxiety and body dissatisfaction were only measured in single studies; however, both were linked to pre-schooler obesity risks; self-esteem was not measured by any studies. We concluded that maternal depressive symptoms are important to consider when assessing risks for obesity in preschool-aged children; however, more research is needed examining the impact of other facets of maternal psychopathology on obesity risk in pre-schoolers. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Middle Schoolers and Magazines: What Teachers Can Learn from Students' Leisure Reading Habits

    Science.gov (United States)

    Gabriel, Rachael; Allington, Richard; Billen, Monica

    2012-01-01

    Teachers, parents, and librarians are constantly looking for methods and materials that engage students as readers and motivate them to increase the time they spend reading. In this article we describe findings from a study of middle schoolers' magazine reading habits that gave us a close look at the power of magazines as supplemental supports for…

  8. Peculiarities of Flexibility Development in Middle Schoolers

    Directory of Open Access Journals (Sweden)

    М. В. Солодовникова

    2015-09-01

    Full Text Available The paper objective is to define the peculiarities of flexibility development in middle schoolers. To solve the tasks set, the study used the following research methods: theoretical analysis and collation of scientific and methodological literature; pedagogical testing, methods of mathematical statistics. Research results. The testing analysis showed statistically unreliable deviations in the results displayed by the fifth-, sixth- and seventh-grade girls in the following tests: “Rotation in the shoulder joint with a staff”, “Backbend from the lying position”, “Forward bend from the sitting position” (p > 0.05. The fifth-, sixth- and seventh-grade girls show improvement in their statistically significant results (p < 0.05 in the following tests: “Raise up from the lying position to the sitting position in 30 seconds”, “Bending and unbending of arms in the lying position”. The testing analysis showed a statistically significant deterioration in the results displayed by the fifth-, sixth- and seventh-grade boys in the following tests: “Rotation in the shoulder joint with a staff”, “Backbend from the lying position” (p < 0.05. The fifth-, sixth- and seventh-grade boys show improvement in their statistically significant results (p < 0.05 in the test " Raise up from the lying position to the sitting position in 30 seconds”, and an improving tendency in the results in the test “Bending and unbending of arms in the lying position”. Conclusions. The informative indicators of flexibility and strength readiness of the 5th-7th-grade boys are “Rotation in the shoulder joint with a staff”, “Backbend from the lying position” and “Raise up from the lying position to the sitting position in 30 seconds”. The informative indicators of strength readiness of the 5th-7th-grade girls are “Raise up from the lying position to the sitting position in 30 seconds”, “Bending and unbending of arms in the lying

  9. Special Physical Preparation of High Schoolers for Performing Parkour Exercises

    Directory of Open Access Journals (Sweden)

    Т. М. Кравчук

    2017-03-01

    Full Text Available The objective is to ground and develop a methodology of special physical preparation of high schoolers for performing parkour elements, and to experimentally verify its effectiveness. Materials and methods: Kharkiv secondary school No. 84 served as the grounds for the study. The participants in the study were boys aged 15-17: 10 persons – in the reference group, and 10 persons – in the experimental group. The methods of the study: theoretical analysis and collation of scientific and methodological literature; pedagogical observation; video recording; biomechanical analysis; talks with experts; pedagogical experiment; mathematical and statistical methods of research materials processing. Results: The experimental group showed positive improvement in the balancing technique from 3.5 points before the experiment to 6.3 after the experiment (p < 0.05; a considerable increase in points in the jumping technique, including jumps onto the wall bars hand-gripping its edge, jumps into landing with a roll, and jumps over obstacle – from 2.9, 4.2 and 4.6 points respectively at the beginning of the experiment to 5.9, 6.7 and 7.8 points respectively after the experiment (p < 0.05; positive significant improvement in the wall bars running results – from 3.2 points at the beginning of the experiment to 6.7 after the experiment (p < 0.05. Conclusions: special sets of exercises have been designed to develop and improve these abilities in parkour, and the effectiveness of the designed methodology has been experimentally verified. The study has proved that, when used in physical training of high schoolers, the special sets of exercises intended to develop parkourists’ speed, strength and coordination abilities contribute to a significant increase in the level of the technique of execution of the main parkour elements.

  10. Applying critical analysis - main methods

    Directory of Open Access Journals (Sweden)

    Miguel Araujo Alonso

    2012-02-01

    Full Text Available What is the usefulness of critical appraisal of literature? Critical analysis is a fundamental condition for the correct interpretation of any study that is subject to review. In epidemiology, in order to learn how to read a publication, we must be able to analyze it critically. Critical analysis allows us to check whether a study fulfills certain previously established methodological inclusion and exclusion criteria. This is frequently used in conducting systematic reviews although eligibility criteria are generally limited to the study design. Critical analysis of literature and be done implicitly while reading an article, as in reading for personal interest, or can be conducted in a structured manner, using explicit and previously established criteria. The latter is done when formally reviewing a topic.

  11. Method for critical current testing

    International Nuclear Information System (INIS)

    Siddall, M.B.; Smathers, D.B.

    1989-01-01

    Superconducting critical current testing software was developed with four important features not feasible with analog test equipment. First, quasi-steady-state sample current conditions are achieved by incrementing sample current, followed by holding some milliseconds until the transient voltage decays before voltage sampling. Then the self-field correction from a helically wound sample is computed and subtracted from each sampled field reading. A copper wire inductively wound shunt which is used for quench protection has a constant measured resistance from which the shunt leakage current is computed and subtracted from the sample current by measuring the shunt voltage after each sample current reading. Finally, the critical current is recomputed from a least squares curve fit to the power law: E=A*In when the correlation coefficient for the fit is high enough to ensure a better result than the raw datum. Comparison with NBS Standard Reference Material (NbTi) and current round robin Nb/sub 3/Sn testing is examined

  12. Critical review on biofilm methods

    DEFF Research Database (Denmark)

    Azeredo, Joana; F. Azevedo, Nuno; Briandet, Romain

    2017-01-01

    Biofilms are widespread in nature and constitute an important strategy implemented by microorganisms to survive in sometimes harsh environmental conditions. They can be beneficial or have a negative impact particularly when formed in industrial settings or on medical devices. As such, research in...... and limitations of several methods. Accordingly, this review aims at helping scientists in finding the most appropriate and up-to-date methods to study their biofilms....

  13. Criticality calculation by the LTSN method

    International Nuclear Information System (INIS)

    Batistela, Claudia H.F.; Vilhena, Marco T. de; Borges, Volnei

    1997-01-01

    This work evaluates criticality parameters (multiplication factor and critical thickness) by the LTS N method in unidimensional slabs homogeneous and heterogeneous considering one-group model and isotropic scattering. The idea of the LTS N method encompasses the following steps: application of the Laplace transform into a set of discrete ordinates equations, analytical solution of the algebraic linear system for the transformed angular fluxes and their reconstruction by the Heaviside expansion technique. The novel feature of the proposed method is based upon the criticality parameters determination by solving a transcendental equation. Numerical results are reported. 12 refs., 2 tabs

  14. Practices and values regarding milk consumption among pre-schoolers in Bangkok.

    Science.gov (United States)

    Yothasamut, Jomkwan; Camfield, Laura; Pfeil, Michael

    2018-12-01

    Thai government agencies and the business sector have been promoting milk consumption. Considering the robust and continual movements by those actors to promote milk consumption among children in Thailand at the national level, this study aims to investigate milk-consumption practices and values towards milk consumption at pre-school, family and individual levels. This cross-sectional qualitative study employs observation and interview methods, along with the Ecological System Theory as a framework. Data were collected from three kindergartens used by families of varying socio-economic status, and the homes of 18 pre-schoolers, aged 3-5 years old, attending these kindergartens, from October 2013-September 2014. Findings reveal kindergartens implemented daily routines to make children drink milk. Practices at home include (i) overfeeding of milk, (ii) preference for fortified milk and (iii) using sweetness to make children drink milk. These practices were underpinned by values that milk is good for children and good parents feed their children milk. These values, in combination with other macro-level measures such as the government's milk-promotion campaigns and the milk industry's marketing, influence the milk-drinking practices of pre-schoolers. The promotion of the benefits of milk prompted children to exceed the recommended milk consumption of 400ml per day. Balanced information on moderation in milk drinking was absent.

  15. Applying Fuzzy Possibilistic Methods on Critical Objects

    DEFF Research Database (Denmark)

    Yazdani, Hossein; Ortiz-Arroyo, Daniel; Choros, Kazimierz

    2016-01-01

    Providing a flexible environment to process data objects is a desirable goal of machine learning algorithms. In fuzzy and possibilistic methods, the relevance of data objects is evaluated and a membership degree is assigned. However, some critical objects objects have the potential ability to affect...... the performance of the clustering algorithms if they remain in a specific cluster or they are moved into another. In this paper we analyze and compare how critical objects affect the behaviour of fuzzy possibilistic methods in several data sets. The comparison is based on the accuracy and ability of learning...... methods to provide a proper searching space for data objects. The membership functions used by each method when dealing with critical objects is also evaluated. Our results show that relaxing the conditions of participation for data objects in as many partitions as they can, is beneficial....

  16. Collaborative Problem Solving Methods towards Critical Thinking

    Science.gov (United States)

    Yin, Khoo Yin; Abdullah, Abdul Ghani Kanesan; Alazidiyeen, Naser Jamil

    2011-01-01

    This research attempts to examine the collaborative problem solving methods towards critical thinking based on economy (AE) and non economy (TE) in the SPM level among students in the lower sixth form. The quasi experiment method that uses the modal of 3X2 factorial is applied. 294 lower sixth form students from ten schools are distributed…

  17. Platonic Dialogue, Maieutic Method and Critical Thinking

    Science.gov (United States)

    Leigh, Fiona

    2007-01-01

    In this paper I offer a reading of one of Plato's later works, the "Sophist", that reveals it to be informed by principles comparable on the face of it with those that have emerged recently in the field of critical thinking. As a development of the famous Socratic method of his teacher, I argue, Plato deployed his own pedagogical method, a…

  18. Development of a transient criticality evaluation method

    International Nuclear Information System (INIS)

    Pain, C.C.; Eaton, M.D.; Miles, B.; Ziver, A.K.; Gomes, J.L.M.A.; Umpleby, A.P.; Piggott, M.D.; Goddard, A.J.H.; Oliveira, C.R.E. de

    2005-01-01

    In developing a transient criticality evaluation method we model, in full spatial/temporal detail, the neutron fluxes and consequent power and the evolving material properties - their flows, energies, phase changes etc. These methods are embodied in the generic method FETCH code which is based as far as possible on basic principles and is capable of use in exploring safety-related situations somewhat beyond the range of experiment. FETCH is a general geometry code capable of addressing a range of criticality issues in fissile materials. The code embodies both transient radiation transport and transient fluid dynamics. Work on powders, granular materials, porous media and solutions is reviewed. The capability for modelling transient criticality for chemical plant, waste matrices and advanced reactors is also outlined. (author)

  19. Computational methods for nuclear criticality safety analysis

    International Nuclear Information System (INIS)

    Maragni, M.G.

    1992-01-01

    Nuclear criticality safety analyses require the utilization of methods which have been tested and verified against benchmarks results. In this work, criticality calculations based on the KENO-IV and MCNP codes are studied aiming the qualification of these methods at the IPEN-CNEN/SP and COPESP. The utilization of variance reduction techniques is important to reduce the computer execution time, and several of them are analysed. As practical example of the above methods, a criticality safety analysis for the storage tubes for irradiated fuel elements from the IEA-R1 research has been carried out. This analysis showed that the MCNP code is more adequate for problems with complex geometries, and the KENO-IV code shows conservative results when it is not used the generalized geometry option. (author)

  20. Parent-child behavioural patterns related to pre-schoolers' overweight/obesity

    Directory of Open Access Journals (Sweden)

    Dagmar Sigmundová

    2017-06-01

    Full Text Available Background: The increasing prevalence of childhood obesity is a global concern. Although childhood obesity has grown as a result of a complex array of interactions among multiple behavioural, biological, and environmental factors, excessive screen time (ST and low levels of physical activity (PA are often discussed as causal factors. Therefore, it is beneficial to identify risky family behavioural patterns contributing to the increasing prevalence of obesity even in pre-schoolers. Objective: The main aim of the study was to assess whether parental obesity and parent-child behavioural patterns (PA and ST affect the odds of overweight/obesity in 4-to-7-year-old preschool children. Methods: We analysed seven-day PA and ST behaviour among families with pre-schoolers that included 194 preschool children (88 girls and 106 boys and their parents (165 mothers and 111 fathers. PA was monitored by means of unsealed Yamax pedometers for at least eight hours a day over seven consecutive days during spring (April/May and autumn (September/October of 2015. ST was recorded by parents on family log book sheets. To assess the odds of parents' obesity and PA/ST variables in relation to child overweight/obesity, a logistic regression (backward method was used. Results: Most children (n = 157 reported normal weight (87 boys, 70 girls, 37 children were overweight or obese (19 boys, 18 girls. Children's excessive ST (> 1 hour/day (OR: 5.65/33.19 on weekdays/weekends, mothers' obesity (OR: 13.80/28.84 on weekdays/weekends, mothers' excessive ST (> 2 hours/ day (OR: 32.46 at weekends, and children's male gender (OR: 38.69 at weekends were significantly (p < .05 associated with higher odds of overweight/obesity in the preschool children. Conclusions: Uncovering parent-child behavioural patterns provides insight into the lifestyle of families with pre-schoolers and is a source of valuable information for designing and implementing family-based intervention

  1. Critical requirements of the SSTR method

    International Nuclear Information System (INIS)

    Gold, R.

    1975-08-01

    Discrepancies have been reported in absolute fission rate measurements observed with Solid State Tract Recorders (SSTR) and fission chambers which lie well outside experimental error. As a result of these comparisons, the reliability of the SSTR method has been seriously questioned, and the fission chamber method has been advanced for sole use in absolute fission rate determinations. In view of the absolute accuracy already reported and well documented for the SSTR method, this conclusion is both surprising and unfortunate. Two independent methods are highly desirable. Moreover, these two methods more than compliment one another, since certain in-core experiments may be amenable to either but not both techniques. Consequently, one cannot abandon the SSTR method without sacrificing crucial advantages. A critical reappraisal of certain aspects of the SSTR method is offered in the hope that the source of the current controversy can be uncovered and a long term beneficial agreement between these two methods can therefore be established. (WHK)

  2. Formal Methods for Life-Critical Software

    Science.gov (United States)

    Butler, Ricky W.; Johnson, Sally C.

    1993-01-01

    The use of computer software in life-critical applications, such as for civil air transports, demands the use of rigorous formal mathematical verification procedures. This paper demonstrates how to apply formal methods to the development and verification of software by leading the reader step-by-step through requirements analysis, design, implementation, and verification of an electronic phone book application. The current maturity and limitations of formal methods tools and techniques are then discussed, and a number of examples of the successful use of formal methods by industry are cited.

  3. The Scientific Method - Critical and Creative Thinking

    Science.gov (United States)

    Cotton, John; Scarlise, Randall

    2011-10-01

    The ``scientific method'' is not just for scientists! Combined with critical thinking, the scientific method can enable students to distinguish credible sources of information from nonsense and become intelligent consumers of information. Professors John Cotton and Randall Scalise illustrate these principles using a series of examples and demonstrations that is enlightening, educational, and entertaining. This lecture/demonstration features highlights from their course (whose unofficial title is ``debunking pseudoscience'' ) which enables students to detect pseudoscience in its many guises: paranormal phenomena, free-energy devices, alternative medicine, and many others.

  4. Growth and development in Chinese pre-schoolers with picky eating behaviour: a cross-sectional study.

    Directory of Open Access Journals (Sweden)

    Yong Xue

    Full Text Available To explore the associations between picky eating behaviour and pre-schoolers' growth and development. Corresponding potential mechanisms, such as nutrient and food subgroup intake, as well as micronutrients in the blood, will be considered.Picky eating behaviour was present if it was reported by parents. From various areas of China, 937 healthy children of 3-7 years old were recruited using a multi-stage stratified cluster sampling method. Children and their mothers' socio-demographic information and children's anthropometry, intelligence, blood samples, one 24-hour dietary intake record and food frequency questionnaire were collected. Z-scores and intelligence tests were used to evaluate growth and development (cognitive development. Multilevel models were employed to verify the associations between picky eating behaviour and growth and development.The prevalence of picky eating as reported by parents was 54% in pre-schoolers. Compared with the non-picky eaters, weight for age in picky eaters was 0.14 z-score (95% CI: -0.25, -0.02; p = 0.017 lower while no significant difference was found in intelligence (p > 0.05. Picky eating behaviour lasting over two years was associated with lower weight for age, as was nit-picking meat (the prevalence from parents' perception was 23% in picky eaters (p 0.05.Picky eating behaviour is reported by parents in half of the Chinese pre-schoolers, which is negatively associated with growth (weight for age. Lower protein and dietary fibre as well as lower iron and zinc intakes were associated with picky eating as were lower intakes of vegetables, fish and cereals.

  5. Growth and development in Chinese pre-schoolers with picky eating behaviour: a cross-sectional study.

    Science.gov (United States)

    Xue, Yong; Zhao, Ai; Cai, Li; Yang, Baoru; Szeto, Ignatius M Y; Ma, Defu; Zhang, Yumei; Wang, Peiyu

    2015-01-01

    To explore the associations between picky eating behaviour and pre-schoolers' growth and development. Corresponding potential mechanisms, such as nutrient and food subgroup intake, as well as micronutrients in the blood, will be considered. Picky eating behaviour was present if it was reported by parents. From various areas of China, 937 healthy children of 3-7 years old were recruited using a multi-stage stratified cluster sampling method. Children and their mothers' socio-demographic information and children's anthropometry, intelligence, blood samples, one 24-hour dietary intake record and food frequency questionnaire were collected. Z-scores and intelligence tests were used to evaluate growth and development (cognitive development). Multilevel models were employed to verify the associations between picky eating behaviour and growth and development. The prevalence of picky eating as reported by parents was 54% in pre-schoolers. Compared with the non-picky eaters, weight for age in picky eaters was 0.14 z-score (95% CI: -0.25, -0.02; p = 0.017) lower while no significant difference was found in intelligence (p > 0.05). Picky eating behaviour lasting over two years was associated with lower weight for age, as was nit-picking meat (the prevalence from parents' perception was 23% in picky eaters) (p 0.05). Picky eating behaviour is reported by parents in half of the Chinese pre-schoolers, which is negatively associated with growth (weight for age). Lower protein and dietary fibre as well as lower iron and zinc intakes were associated with picky eating as were lower intakes of vegetables, fish and cereals.

  6. Criticality calculation method for mixer-settlers

    International Nuclear Information System (INIS)

    Gonda, Kozo; Aoyagi, Haruki; Nakano, Ko; Kamikawa, Hiroshi.

    1980-01-01

    A new criticality calculation code MACPEX has been developed to evaluate and manage the criticality of the process in the extractor of mixer-settler type. MACPEX can perform the combined calculation with the PUREX process calculation code MIXSET, to get the neutron flux and the effective multiplication constant in the mixer-settlers. MACPEX solves one-dimensional diffusion equation by the explicit difference method and the standard source-iteration technique. The characteristics of MACPEX are as follows. 1) Group constants of 4 energy groups for the 239 Pu-H 2 O solution, water, polyethylene and SUS 28 are provided. 2) The group constants of the 239 Pu-H 2 O solution are given by the functional formulae of the plutonium concentration, which is less than 50 g/l. 3) Two boundary conditions of the vacuum condition and the reflective condition are available in this code. 4) The geometrical bucklings can be calculated for a certain energy group and/or region by using the three dimentional neutron flux profiles obtained by CITATION. 5) The buckling correction search can be carried out in order to get a desired k sub(eff). (author)

  7. Monte Carlo method for array criticality calculations

    International Nuclear Information System (INIS)

    Dickinson, D.; Whitesides, G.E.

    1976-01-01

    The Monte Carlo method for solving neutron transport problems consists of mathematically tracing paths of individual neutrons collision by collision until they are lost by absorption or leakage. The fate of the neutron after each collision is determined by the probability distribution functions that are formed from the neutron cross-section data. These distributions are sampled statistically to establish the successive steps in the neutron's path. The resulting data, accumulated from following a large number of batches, are analyzed to give estimates of k/sub eff/ and other collision-related quantities. The use of electronic computers to produce the simulated neutron histories, initiated at Los Alamos Scientific Laboratory, made the use of the Monte Carlo method practical for many applications. In analog Monte Carlo simulation, the calculation follows the physical events of neutron scattering, absorption, and leakage. To increase calculational efficiency, modifications such as the use of statistical weights are introduced. The Monte Carlo method permits the use of a three-dimensional geometry description and a detailed cross-section representation. Some of the problems in using the method are the selection of the spatial distribution for the initial batch, the preparation of the geometry description for complex units, and the calculation of error estimates for region-dependent quantities such as fluxes. The Monte Carlo method is especially appropriate for criticality safety calculations since it permits an accurate representation of interacting units of fissile material. Dissimilar units, units of complex shape, moderators between units, and reflected arrays may be calculated. Monte Carlo results must be correlated with relevant experimental data, and caution must be used to ensure that a representative set of neutron histories is produced

  8. Analysis of construction dynamic plan using fuzzy critical path method

    Directory of Open Access Journals (Sweden)

    Kurij Kazimir V.

    2014-01-01

    Full Text Available Critical Path Method (CPM technique has become widely recognized as valuable tool for the planning and scheduling large construction projects. The aim of this paper is to present an analytical method for finding the Critical Path in the precedence network diagram where the duration of each activity is represented by a trapezoidal fuzzy number. This Fuzzy Critical Path Method (FCPM uses a defuzzification formula for trapezoidal fuzzy number and applies it on the total float (slack time for each activity in the fuzzy precedence network to find the critical path. The method presented in this paper is very effective in determining the critical activities and finding the critical paths.

  9. Peculiarities of Use of Dancing Exercises in Physical Education of Female High Schoolers

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    Т. М. Кравчук

    2015-12-01

    Full Text Available The purpose of the research is to ground and develop the methods of the use of dancing exercises at physical training classes in high school and to experimentally verify their effectiveness. Research methods. Theoretical ones: study and analysis of pedagogical, scientific and methodological literature on the problems under research; a complex of empirical research methods: research and experimental work, observations, questionnaires, testing; statistical methods of research and data reduction. Research results. The paper reveals the peculiarities of the use of dancing exercises at physical training classes in high school. It shows that dancing exercises can and must be part of the physical education of high schoolers to develop their strength, flexibility, endurance, coordination abilities and to cultivate movement culture, musicality, dancing abilities and aesthetic taste. The study proves that the use of dancing exercises of classical choreography, rhythmic gymnastics and health-improving aerobics at the physical training classes in high school helps increase the level of development of flexibility, strength and agility.

  10. Does Mind Wandering Reflect Executive Function or Executive Failure? Comment on Smallwood and Schooler (2006) and Watkins (2008)

    Science.gov (United States)

    McVay, Jennifer C.; Kane, Michael J.

    2010-01-01

    In this comment, we contrast different conceptions of mind wandering that were presented in 2 recent theoretical reviews: Smallwood and Schooler (2006) and Watkins (2008). We also introduce a new perspective on the role of executive control in mind wandering by integrating empirical evidence presented in Smallwood and Schooler with 2 theoretical…

  11. On the criticism to the classical method

    Directory of Open Access Journals (Sweden)

    Cláudio Gontijo

    2000-01-01

    Full Text Available This article addresses the most common criticisms on the "surplus approach''. It shows that the classical method avoids the excess of abstraction of neoclassical general equilibrium theory, which produces models that have no empirical content, and the lack of abstraction of the post-Keynesian school which does not accept equilibrium. Taking reality as a chain of accidental events connected in a dynamic logical process, the neoclassical school conceives market prices as empirical phenomena that nevertheless gravitate around moving equilibrium prices thanks to the adjustment mechanisms. Though this gravitation process should be conceived as an axiom of logic, it can be modeled in such a way as to produce stable results under quite reasonable assumptions. Finally, it shows that the classical concept of competition can be used for explaining profit rate differentials, which are the bases of the theory of oligopoly pricing.Este artigo analisa as principais críticas à "abordagem do excedente econômico''. Ele mostra que o método clássico evita o excesso de abstração da teoria neoclássica do equilíbrio geral, que produz modelos sem conteúdo empírico, e a falta de abstração da escola pós-keynesiana, que não aceita o conceito de equilíbrio. Considerando a realidade como uma cadeia de eventos acidentais conectados num processo dinâmico, a escola clássica concebe os preços de mercado como fenômenos empíricos que gravitam em torno dos preços de equilíbrio graças aos mecanismos de ajustamento. Ainda que o processo de gravitação deva ser concebido como um axioma lógico, ele pode ser modelado de forma a produzir resultados estáveis sob hipóteses bastante razoáveis. Finalmente, o artigo mostra que o conceito clássico de concorrência pode ser utilizado para explicar os diferenciais de taxa de lucro que representam a base da teoria de preços em regime de oligopólio.

  12. Visual stimuli in intervention approaches for pre-schoolers diagnosed with phonological delay.

    Science.gov (United States)

    Pedro, Cassandra Ferreira; Lousada, Marisa; Hall, Andreia; Jesus, Luis M T

    2018-04-01

    The aim of this study was to develop and content validate specific speech and language intervention picture cards: The Letter-Sound (L&S) cards. The present study was also focused on assessing the influence of these cards on letter-sound correspondences and speech sound production. An expert panel of six speech and language therapists analysed and discussed the L&S cards based on several criteria previously established. A Speech and Language Therapist carried out a 6-week therapeutic intervention with a group of seven Portuguese phonologically delayed pre-schoolers aged 5;3 to 6;5. The modified Bland-Altman method revealed good agreement among evaluators, that is the majority of the values was between the agreement limits. Additional outcome measures were collected before and after the therapeutic intervention process. Results indicate that the L&S cards facilitate the acquisition of letter-sound correspondences. Regarding speech sound production, some improvements were also observed at word level. The L&S cards are therefore likely to give phonetic cues, which are crucial for the correct production of therapeutic targets. These visual cues seemed to have helped children with phonological delay develop the above-mentioned skills.

  13. Critical Appraisal of Mixed Methods Studies

    Science.gov (United States)

    Heyvaert, Mieke; Hannes, Karin; Maes, Bea; Onghena, Patrick

    2013-01-01

    In several subdomains of the social, behavioral, health, and human sciences, research questions are increasingly answered through mixed methods studies, combining qualitative and quantitative evidence and research elements. Accordingly, the importance of including those primary mixed methods research articles in systematic reviews grows. It is…

  14. Methods optimization for the first time core critical

    International Nuclear Information System (INIS)

    Yan Liang

    2014-01-01

    The PWR reactor core commissioning programs the content of the first critical reactor physics experiment, and describes thc physical test method. However, all the methods arc not exactly the same but efficient. This article aims to enhance the reactor for the first time in the process of critical safety, shorten the overall time of critical physical test for the first time, and improve the integrity of critical physical test data for the first time and accuracy, eventually to improve the operation of the plant economic benefit adopting sectional dilution, power feedback for Doppler point improvement of physical test methods, and so on. (author)

  15. Pre-Schoolers' Verbal and Behavioral Responses as Indicators of Attitudes and Scientific Curiosity

    Science.gov (United States)

    Baruch, Yael Kesner; Spektor-Levy, Ornit; Mashal, Nira

    2016-01-01

    Today, early science education is a well-accepted view. Enhancing children's curiosity about the natural world and fostering positive attitudes toward science are primary goals of science education. However, questions remain regarding the appropriate ways to identify, nurture, and study these emotional states in pre-schoolers. This study examines…

  16. Bilingual Latino Middle Schoolers on Languaging and Racialization in the US

    Science.gov (United States)

    Hesson, Sarah

    2016-01-01

    This dissertation explores bilingual Latino middle schoolers' articulated understandings of their language practices as well as the links between language practices and processes of racialization and discrimination in the US. The research was conducted in the context of an after-school program whose explicit aim was to not only document students'…

  17. Pre-Schoolers' Interest and Caring Behaviour around a Humanoid Robot

    Science.gov (United States)

    Ioannou, Andri; Andreou, Emily; Christofi, Maria

    2015-01-01

    This exploratory case study involved a humanoid robot, NAO, and four pre-schoolers. NAO was placed in an indoor playground together with other toys and appeared as a peer who played, talked, danced and said stories. Analysis of video recordings focused on children's behaviour around NAO and how the robot gained children's attention and…

  18. Don't Bother Me, I'm Reading: Graphic Nonfiction for Middle Schoolers

    Science.gov (United States)

    Gutierrez, Peter

    2008-01-01

    This article offers a savvy guide to the best graphic nonfiction books for middle schoolers. These include: "Ronald Reagan: A Graphic Biography" by Andrew Hefler; "Clan Apis" by Jay Hosler; and "Corpses and Skeletons: The Science of Forensic Anthropology" by Rob Shone.

  19. Experimental Study of Short-Term Training in Social Cognition in Pre-Schoolers

    Science.gov (United States)

    Houssa, Marine; Nader-Grosbois, Nathalie; Jacobs, Emilie

    2014-01-01

    Using an experimental approach, our study examined the differentiated effects on pre-schoolers' social cognition of two short-term social information processing (SIP) and Theory of Mind (ToM) training sessions dealing with emotions and beliefs. The links between ToM, SIP, and social adjustment or externalizing behavior were examined. 47…

  20. The Inductive Method of Teaching Visual Art Criticism.

    Science.gov (United States)

    Clements, Robert D.

    1979-01-01

    The author describes how the true principles of the scientific inductive method are not opposed to the principles of teaching visual art criticism, and suggests that the inductive method of teaching visual art criticism strips it of its mystique in order to make clear its vital role in intellectual development. (KC)

  1. Perceptions of the use of critical thinking teaching methods.

    Science.gov (United States)

    Kowalczyk, Nina; Hackworth, Ruth; Case-Smith, Jane

    2012-01-01

    To identify the perceived level of competence in teaching and assessing critical thinking skills and the difficulties facing radiologic science program directors in implementing student-centered teaching methods. A total of 692 program directors received an invitation to complete an electronic survey soliciting information regarding the importance of critical thinking skills, their confidence in applying teaching methods and assessing student performance, and perceived obstacles. Statistical analysis included descriptive data, correlation coefficients, and ANOVA. Responses were received from 317 participants indicating program directors perceive critical thinking to be an essential element in the education of the student; however, they identified several areas for improvement. A high correlation was identified between the program directors' perceived level of skill and their confidence in critical thinking, and between their perceived level of skill and ability to assess the students' critical thinking. Key barriers to implementing critical thinking teaching strategies were identified. Program directors value the importance of implementing critical thinking teaching methods and perceive a need for professional development in critical thinking educational methods. Regardless of the type of educational institution in which the academic program is located, the level of education held by the program director was a significant factor regarding perceived confidence in the ability to model critical thinking skills and the ability to assess student critical thinking skills.

  2. Dialectical Method and the Critical Political Economy of Culture

    Directory of Open Access Journals (Sweden)

    Brice Nixon

    2012-05-01

    Full Text Available This article argues that the quality that defines critical political economy is its critical method. Definitions of the critical political economy of culture are considered and shown to focus on specific theoretical concerns while not fully addressing the fundamental issue of method. Method is here discussed in terms of the way human reason is used to produce knowledge. A critical method for Marx is a historical materialist dialectical method, thus this paper argues for a deeper consideration of the Marxist dialectical method in relation to critical political-economic theorizing. Sources for methodological consideration from Marx to 20th-century Western Marxists are outlined. The potential contribution of the Marxist dialectical method in the continued development of the critical political economy of culture is demonstrated by showing the possibility of developing a complementary critical political economy of consciousness. Smythe’s theorizing of audiences as workers is considered as a useful starting point, and its potential development through incorporation of the work of other critical scholars of media and culture is outlined.

  3. Nurse educators' critical thinking: A mixed methods exploration.

    Science.gov (United States)

    Raymond, Christy; Profetto-McGrath, Joanne; Myrick, Florence; Strean, William B

    2018-07-01

    Nurse educator's critical thinking remains unexamined as a key factor in the development of students' critical thinking. The objective of this study is to understand how nurse educators reveal their critical thinking in the clinical setting while supervising students. This study uses a single-phase triangulation mixed methods design with multiple data gathering techniques. Participants for this study are clinical nurse educators from a large Western Canadian baccalaureate nursing program who teach 2nd or 3rd year students in medical-surgical settings. Participants for this study completed a demographic survey, the California Critical Thinking Skills Test (CCTST), the California Critical Thinking Disposition Inventory (CCTDI), participant observation in a clinical practice setting, and semi-structured interviews. The results from the California Critical Thinking assessments (CCTST and CCTDI) show that participants are positively inclined and have a moderate to strong ability to think critically, similar to other studies. Participants find it difficult to describe how they reveal their critical thinking in the clinical setting, yet all participants use role modeling and questioning to share their critical thinking with students. When the quantitative and qualitative results are compared, it is apparent that the confidence in reasoning subscale of the California Critical Thinking Skills Test is higher in those educators who more frequently demonstrate and voice engagement in reflective activities. Dispositions associated with critical thinking, as measured by the California Critical Thinking Disposition Inventory, are more easily observed compared to critical thinking skills. This study is a beginning exploration of nurse educators' critical thinking-in-action. Our mixed methods approach uncovers a valuable approach to understanding the complexity of nurse educators' critical thinking. Further study is needed to uncover how nurse educators' can specifically enact

  4. Review of studies on criticality safety evaluation and criticality experiment methods

    International Nuclear Information System (INIS)

    Naito, Yoshitaka; Yamamoto, Toshihiro; Misawa, Tsuyoshi; Yamane, Yuichi

    2013-01-01

    Since the early 1960s, many studies on criticality safety evaluation have been conducted in Japan. Computer code systems were developed initially by employing finite difference methods, and more recently by using Monte Carlo methods. Criticality experiments have also been carried out in many laboratories in Japan as well as overseas. By effectively using these study results, the Japanese Criticality Safety Handbook was published in 1988, almost the intermediate point of the last 50 years. An increased interest has been shown in criticality safety studies, and a Working Party on Nuclear Criticality Safety (WPNCS) was set up by the Nuclear Science Committee of Organisation Economic Co-operation and Development in 1997. WPNCS has several task forces in charge of each of the International Criticality Safety Benchmark Evaluation Program (ICSBEP), Subcritical Measurement, Experimental Needs, Burn-up Credit Studies and Minimum Critical Values. Criticality safety studies in Japan have been carried out in cooperation with WPNCS. This paper describes criticality safety study activities in Japan along with the contents of the Japanese Criticality Safety Handbook and the tasks of WPNCS. (author)

  5. Research on neutron source multiplication method in nuclear critical safety

    International Nuclear Information System (INIS)

    Zhu Qingfu; Shi Yongqian; Hu Dingsheng

    2005-01-01

    The paper concerns in the neutron source multiplication method research in nuclear critical safety. Based on the neutron diffusion equation with external neutron source the effective sub-critical multiplication factor k s is deduced, and k s is different to the effective neutron multiplication factor k eff in the case of sub-critical system with external neutron source. The verification experiment on the sub-critical system indicates that the parameter measured with neutron source multiplication method is k s , and k s is related to the external neutron source position in sub-critical system and external neutron source spectrum. The relation between k s and k eff and the effect of them on nuclear critical safety is discussed. (author)

  6. Critical temperature: A quantitative method of assessing cold tolerance

    Science.gov (United States)

    D.H. DeHayes; M.W., Jr. Williams

    1989-01-01

    Critical temperature (Tc), defined as the highest temperature at which freezing injury to plant tissues can be detected, provides a biologically meaningful and statistically defined assessment of the relative cold tolerance of plant tissues. A method is described for calculating critical temperatures in laboratory freezing studies that use...

  7. Comparison of the dose evaluation methods for criticality accident

    International Nuclear Information System (INIS)

    Shimizu, Yoshio; Oka, Tsutomu

    2004-01-01

    The improvement of the dose evaluation method for criticality accidents is important to rationalize design of the nuclear fuel cycle facilities. The source spectrums of neutron and gamma ray of a criticality accident depend on the condition of the source, its materials, moderation, density and so on. The comparison of the dose evaluation methods for a criticality accident is made. Some methods, which are combination of criticality calculation and shielding calculation, are proposed. Prompt neutron and gamma ray doses from nuclear criticality of some uranium systems have been evaluated as the Nuclear Criticality Slide Rule. The uranium metal source (unmoderated system) and the uranyl nitrate solution source (moderated system) in the rule are evaluated by some calculation methods, which are combinations of code and cross section library, as follows: (a) SAS1X (ENDF/B-IV), (b) MCNP4C (ENDF/B-VI)-ANISN (DLC23E or JSD120), (c) MCNP4C-MCNP4C (ENDF/B-VI). They have consisted of criticality calculation and shielding calculation. These calculation methods are compared about the tissue absorbed dose and the spectrums at 2 m from the source. (author)

  8. Formal methods for industrial critical systems a survey of applications

    CERN Document Server

    Margaria-Steffen, Tiziana

    2012-01-01

    "Today, formal methods are widely recognized as an essential step in the design process of industrial safety-critical systems. In its more general definition, the term formal methods encompasses all notations having a precise mathematical semantics, together with their associated analysis methods, that allow description and reasoning about the behavior of a system in a formal manner.Growing out of more than a decade of award-winning collaborative work within the European Research Consortium for Informatics and Mathematics, Formal Methods for Industrial Critical Systems: A Survey of Applications presents a number of mainstream formal methods currently used for designing industrial critical systems, with a focus on model checking. The purpose of the book is threefold: to reduce the effort required to learn formal methods, which has been a major drawback for their industrial dissemination; to help designers to adopt the formal methods which are most appropriate for their systems; and to offer a panel of state-of...

  9. Critical Debates in Teaching Research Methods in the Social Sciences

    Science.gov (United States)

    Gunn, Andrew

    2017-01-01

    This paper explores some of the critical debates in social science research methods education and is set out in three parts. The first section introduces the importance and relevance of research methods to the social sciences. It then outlines the problems and challenges experienced in the teaching and learning of research methods, which are…

  10. Iterative acceleration methods for Monte Carlo and deterministic criticality calculations

    International Nuclear Information System (INIS)

    Urbatsch, T.J.

    1995-11-01

    If you have ever given up on a nuclear criticality calculation and terminated it because it took so long to converge, you might find this thesis of interest. The author develops three methods for improving the fission source convergence in nuclear criticality calculations for physical systems with high dominance ratios for which convergence is slow. The Fission Matrix Acceleration Method and the Fission Diffusion Synthetic Acceleration (FDSA) Method are acceleration methods that speed fission source convergence for both Monte Carlo and deterministic methods. The third method is a hybrid Monte Carlo method that also converges for difficult problems where the unaccelerated Monte Carlo method fails. The author tested the feasibility of all three methods in a test bed consisting of idealized problems. He has successfully accelerated fission source convergence in both deterministic and Monte Carlo criticality calculations. By filtering statistical noise, he has incorporated deterministic attributes into the Monte Carlo calculations in order to speed their source convergence. He has used both the fission matrix and a diffusion approximation to perform unbiased accelerations. The Fission Matrix Acceleration method has been implemented in the production code MCNP and successfully applied to a real problem. When the unaccelerated calculations are unable to converge to the correct solution, they cannot be accelerated in an unbiased fashion. A Hybrid Monte Carlo method weds Monte Carlo and a modified diffusion calculation to overcome these deficiencies. The Hybrid method additionally possesses reduced statistical errors

  11. Iterative acceleration methods for Monte Carlo and deterministic criticality calculations

    Energy Technology Data Exchange (ETDEWEB)

    Urbatsch, T.J.

    1995-11-01

    If you have ever given up on a nuclear criticality calculation and terminated it because it took so long to converge, you might find this thesis of interest. The author develops three methods for improving the fission source convergence in nuclear criticality calculations for physical systems with high dominance ratios for which convergence is slow. The Fission Matrix Acceleration Method and the Fission Diffusion Synthetic Acceleration (FDSA) Method are acceleration methods that speed fission source convergence for both Monte Carlo and deterministic methods. The third method is a hybrid Monte Carlo method that also converges for difficult problems where the unaccelerated Monte Carlo method fails. The author tested the feasibility of all three methods in a test bed consisting of idealized problems. He has successfully accelerated fission source convergence in both deterministic and Monte Carlo criticality calculations. By filtering statistical noise, he has incorporated deterministic attributes into the Monte Carlo calculations in order to speed their source convergence. He has used both the fission matrix and a diffusion approximation to perform unbiased accelerations. The Fission Matrix Acceleration method has been implemented in the production code MCNP and successfully applied to a real problem. When the unaccelerated calculations are unable to converge to the correct solution, they cannot be accelerated in an unbiased fashion. A Hybrid Monte Carlo method weds Monte Carlo and a modified diffusion calculation to overcome these deficiencies. The Hybrid method additionally possesses reduced statistical errors.

  12. Feasibility study on heterogeneous method in criticality calculations

    International Nuclear Information System (INIS)

    Prati, A.

    1977-01-01

    The criticality of finite heterogeneous assemblies is analysed by the heterogeneous methods employing the Eigen-function analysis. The moderation is treated by the Fermi age theory. The system is analysed in two dimensional rectangular coordinates. The criticality and the fluxes are determined for systems with small and large number of fuel rods. The convergence and the residual error in the modal analysis are discussed. (author)

  13. Validation of calculational methods for nuclear criticality safety - approved 1975

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    The American National Standard for Nuclear Criticality Safety in Operations with Fissionable Materials Outside Reactors, N16.1-1975, states in 4.2.5: In the absence of directly applicable experimental measurements, the limits may be derived from calculations made by a method shown to be valid by comparison with experimental data, provided sufficient allowances are made for uncertainties in the data and in the calculations. There are many methods of calculation which vary widely in basis and form. Each has its place in the broad spectrum of problems encountered in the nuclear criticality safety field; however, the general procedure to be followed in establishing validity is common to all. The standard states the requirements for establishing the validity and area(s) of applicability of any calculational method used in assessing nuclear criticality safety

  14. Autoethnography as a research method: Advantages, limitations and criticisms

    Directory of Open Access Journals (Sweden)

    Mariza G. Méndez

    2014-01-01

    Full Text Available The aim of this article is to review the literature  on autoethnography as a research method. It will first describe what is meant by autoethnography, or evocative narratives, and consider the particular features of this type of method. The paper will go on to explore the advantages, limitations and criticisms this research method has endured since its emergence during the 1980s. Finally, the different approaches to the evaluation of autoethnography will be reviewed.

  15. Cluster monte carlo method for nuclear criticality safety calculation

    International Nuclear Information System (INIS)

    Pei Lucheng

    1984-01-01

    One of the most important applications of the Monte Carlo method is the calculation of the nuclear criticality safety. The fair source game problem was presented at almost the same time as the Monte Carlo method was applied to calculating the nuclear criticality safety. The source iteration cost may be reduced as much as possible or no need for any source iteration. This kind of problems all belongs to the fair source game prolems, among which, the optimal source game is without any source iteration. Although the single neutron Monte Carlo method solved the problem without the source iteration, there is still quite an apparent shortcoming in it, that is, it solves the problem without the source iteration only in the asymptotic sense. In this work, a new Monte Carlo method called the cluster Monte Carlo method is given to solve the problem further

  16. Review of teaching methods and critical thinking skills.

    Science.gov (United States)

    Kowalczyk, Nina

    2011-01-01

    Critical information is needed to inform radiation science educators regarding successful critical thinking educational strategies. From an evidence-based research perspective, systematic reviews are identified as the most current and highest level of evidence. Analysis at this high level is crucial in analyzing those teaching methods most appropriate to the development of critical thinking skills. To conduct a systematic literature review to identify teaching methods that demonstrate a positive effect on the development of students' critical thinking skills and to identify how these teaching strategies can best translate to radiologic science educational programs. A comprehensive literature search was conducted resulting in an assessment of 59 full reports. Nineteen of the 59 reports met inclusion criteria and were reviewed based on the level of evidence presented. Inclusion criteria included studies conducted in the past 10 years on sample sizes of 20 or more individuals demonstrating use of specific teaching interventions for 5 to 36 months in postsecondary health-related educational programs. The majority of the research focused on problem-based learning (PBL) requiring standardized small-group activities. Six of the 19 studies focused on PBL and demonstrated significant differences in student critical thinking scores. PBL, as described in the nursing literature, is an effective teaching method that should be used in radiation science education. ©2011 by the American Society of Radiologic Technologists.

  17. Statistical methods for accurately determining criticality code bias

    International Nuclear Information System (INIS)

    Trumble, E.F.; Kimball, K.D.

    1997-01-01

    A system of statistically treating validation calculations for the purpose of determining computer code bias is provided in this paper. The following statistical treatments are described: weighted regression analysis, lower tolerance limit, lower tolerance band, and lower confidence band. These methods meet the criticality code validation requirements of ANS 8.1. 8 refs., 5 figs., 4 tabs

  18. Complexity, Methodology and Method: Crafting a Critical Process of Research

    Science.gov (United States)

    Alhadeff-Jones, Michel

    2013-01-01

    This paper defines a theoretical framework aiming to support the actions and reflections of researchers looking for a "method" in order to critically conceive the complexity of a scientific process of research. First, it starts with a brief overview of the core assumptions framing Morin's "paradigm of complexity" and Le…

  19. CPM (Critical Path Method) as a Curriculum Tool.

    Science.gov (United States)

    Mongerson, M. Duane

    This document discusses and illustrates the use of the Critical Path Method (CPM) as a tool for developing curriculum. In so doing a brief review of the evolution of CPM as a management tool developed by E. I. duPont de Nemours Company is presented. It is also noted that CPM is only a method of sequencing learning activities and not an end unto…

  20. Use of deterministic methods in survey calculations for criticality problems

    International Nuclear Information System (INIS)

    Hutton, J.L.; Phenix, J.; Course, A.F.

    1991-01-01

    A code package using deterministic methods for solving the Boltzmann Transport equation is the WIMS suite. This has been very successful for a range of situations. In particular it has been used with great success to analyse trends in reactivity with a range of changes in state. The WIMS suite of codes have a range of methods and are very flexible in the way they can be combined. A wide variety of situations can be modelled ranging through all the current Thermal Reactor variants to storage systems and items of chemical plant. These methods have recently been enhanced by the introduction of the CACTUS method. This is based on a characteristics technique for solving the Transport equation and has the advantage that complex geometrical situations can be treated. In this paper the basis of the method is outlined and examples of its use are illustrated. In parallel with these developments the validation for out of pile situations has been extended to include experiments with relevance to criticality situations. The paper will summarise this evidence and show how these results point to a partial re-adoption of deterministic methods for some areas of criticality. The paper also presents results to illustrate the use of WIMS in criticality situations and in particular show how it can complement codes such as MONK when used for surveying the reactivity effect due to changes in geometry or materials. (Author)

  1. Bayesian methods for chromosome dosimetry following a criticality accident

    International Nuclear Information System (INIS)

    Brame, R.S.; Groer, P.G.

    2003-01-01

    Radiation doses received during a criticality accident will be from a combination of fission spectrum neutrons and gamma rays. It is desirable to estimate the total dose, as well as the neutron and gamma doses. Present methods for dose estimation with chromosome aberrations after a criticality accident use point estimates of the neutron to gamma dose ratio obtained from personnel dosemeters and/or accident reconstruction calculations. In this paper a Bayesian approach to dose estimation with chromosome aberrations is developed that allows the uncertainty of the dose ratio to be considered. Posterior probability densities for the total and the neutron and gamma doses were derived. (author)

  2. New procedure for criticality search using coarse mesh nodal methods

    International Nuclear Information System (INIS)

    Pereira, Wanderson F.; Silva, Fernando C. da; Martinez, Aquilino S.

    2011-01-01

    The coarse mesh nodal methods have as their primary goal to calculate the neutron flux inside the reactor core. Many computer systems use a specific form of calculation, which is called nodal method. In classical computing systems that use the criticality search is made after the complete convergence of the iterative process of calculating the neutron flux. In this paper, we proposed a new method for the calculation of criticality, condition which will be over very iterative process of calculating the neutron flux. Thus, the processing time for calculating the neutron flux was reduced by half compared with the procedure developed by the Nuclear Engineering Program of COPPE/UFRJ (PEN/COPPE/UFRJ). (author)

  3. New procedure for criticality search using coarse mesh nodal methods

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Wanderson F.; Silva, Fernando C. da; Martinez, Aquilino S., E-mail: wneto@con.ufrj.b, E-mail: fernando@con.ufrj.b, E-mail: Aquilino@lmp.ufrj.b [Coordenacao dos Programas de Pos-Graduacao de Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear

    2011-07-01

    The coarse mesh nodal methods have as their primary goal to calculate the neutron flux inside the reactor core. Many computer systems use a specific form of calculation, which is called nodal method. In classical computing systems that use the criticality search is made after the complete convergence of the iterative process of calculating the neutron flux. In this paper, we proposed a new method for the calculation of criticality, condition which will be over very iterative process of calculating the neutron flux. Thus, the processing time for calculating the neutron flux was reduced by half compared with the procedure developed by the Nuclear Engineering Program of COPPE/UFRJ (PEN/COPPE/UFRJ). (author)

  4. Computational Methods for Sensitivity and Uncertainty Analysis in Criticality Safety

    International Nuclear Information System (INIS)

    Broadhead, B.L.; Childs, R.L.; Rearden, B.T.

    1999-01-01

    Interest in the sensitivity methods that were developed and widely used in the 1970s (the FORSS methodology at ORNL among others) has increased recently as a result of potential use in the area of criticality safety data validation procedures to define computational bias, uncertainties and area(s) of applicability. Functional forms of the resulting sensitivity coefficients can be used as formal parameters in the determination of applicability of benchmark experiments to their corresponding industrial application areas. In order for these techniques to be generally useful to the criticality safety practitioner, the procedures governing their use had to be updated and simplified. This paper will describe the resulting sensitivity analysis tools that have been generated for potential use by the criticality safety community

  5. Mixed-methods research in nursing - a critical review.

    Science.gov (United States)

    Bressan, Valentina; Bagnasco, Annamaria; Aleo, Giuseppe; Timmins, Fiona; Barisone, Michela; Bianchi, Monica; Pellegrini, Ramona; Sasso, Loredana

    2017-10-01

    To review the use of mixed-methods research in nursing with a particular focus on the extent to which current practice informs nurse researchers. It also aimed to highlight gaps in current knowledge, understanding and reporting of this type of research. Mixed-methods research is becoming increasingly popular among nurses and healthcare professionals. Emergent findings from this type of research are very useful for nurses in practice. The combination of both quantitative and qualitative methods provides a scientific base for practice but also richness from the qualitative enquiry. However, at the same time mixed-methods research is underdeveloped. This study identified mixed-methods research papers and critically evaluated their usefulness for research practice. To support the analysis, we performed a two-stage search using CINAHL to find papers with titles that included the key term 'mixed method'. An analysis of studies that used mixed-methods research revealed some inconsistencies in application and reporting. Attempts to use two distinct research methods in these studies often meant that one or both aspects had limitations. Overall methods were applied in a less rigorous way. This has implications for providing somewhat limited direction for novice researchers. There is also potential for application of evidence in healthcare practice that limited validity. This study highlights current gaps in knowledge, understanding and reporting of mixed-methods research. While these methods are useful to gain insight into clinical problems nurses lack guidance with this type of research. This study revealed that the guidance provided by current mixed-methods research is inconsistent and incomplete and this compounds the lack of available direction. There is an urgent need to develop robust guidelines for using mixed-methods research so that findings may be critically implemented in practice. © 2016 John Wiley & Sons Ltd.

  6. Design and descriptive results of the "Growth, Exercise and Nutrition Epidemiological Study In preSchoolers": The GENESIS Study

    Directory of Open Access Journals (Sweden)

    Manios Yannis

    2006-02-01

    Full Text Available Abstract Background The Growth, Exercise and Nutrition Epidemiological Study in preSchoolers (GENESIS attempts to evaluate the food and nutrient intakes, as well as growth and development of a representative sample of Greek toddlers and preschool children. In the current work the study design, data collection procedures and some preliminary data of the GENESIS study are presented. Methods From April 2003 to July 2004, 1218 males and 1156 females 1 to 5 years old, stratified by parental educational level (Census 1999, were examined from 105 nurseries in five counties. Approximately 300 demographic, lifestyle, physical activity, dietary, anthropometrical and DNA variables have been recorded from the study population (children and parents. Results Regarding anthropometrical indices, boys were found to be taller than girls at all ages (P Conclusion The prevalence of overweight in the current preschool population is considerably high. Future but more extensive analyses of the GENESIS data will be able to reveal the interactions of the parameters leading to this phenomenon.

  7. Critical wall shear stress for the EHEDG test method

    DEFF Research Database (Denmark)

    Jensen, Bo Boye Busk; Friis, Alan

    2004-01-01

    In order to simulate the results of practical cleaning tests on closed processing equipment, based on wall shear stress predicted by computational fluid dynamics, a critical wall shear stress is required for that particular cleaning method. This work presents investigations that provide a critical...... wall shear stress of 3 Pa for the standardised EHEDG cleaning test method. The cleaning tests were performed on a test disc placed in a radial flowcell assay. Turbulent flow conditions were generated and the corresponding wall shear stresses were predicted from CFD simulations. Combining wall shear...... stress predictions from a simulation using the low Re k-epsilon and one using the two-layer model of Norris and Reynolds were found to produce reliable predictions compared to empirical solutions for the ideal flow case. The comparison of wall shear stress curves predicted for the real RFC...

  8. Efficient model learning methods for actor-critic control.

    Science.gov (United States)

    Grondman, Ivo; Vaandrager, Maarten; Buşoniu, Lucian; Babuska, Robert; Schuitema, Erik

    2012-06-01

    We propose two new actor-critic algorithms for reinforcement learning. Both algorithms use local linear regression (LLR) to learn approximations of the functions involved. A crucial feature of the algorithms is that they also learn a process model, and this, in combination with LLR, provides an efficient policy update for faster learning. The first algorithm uses a novel model-based update rule for the actor parameters. The second algorithm does not use an explicit actor but learns a reference model which represents a desired behavior, from which desired control actions can be calculated using the inverse of the learned process model. The two novel methods and a standard actor-critic algorithm are applied to the pendulum swing-up problem, in which the novel methods achieve faster learning than the standard algorithm.

  9. Prevalence of food allergy in infants and pre-schoolers in Brazil.

    Science.gov (United States)

    Gonçalves, L C P; Guimarães, T C P; Silva, R M; Cheik, M F A; de Ramos Nápolis, A C; Barbosa E Silva, G; Segundo, G R S

    Food allergy is an increasing problem in public health, especially in childhood. Its incidence has increased in the last decade. Despite this, estimates of the actual incidence and prevalence are uncertain. The aim of this study was to estimate the prevalence of food allergy in infants and pre-schoolers. The parents of 3897 children completed questionnaires on the occurrence of any reaction to food. Children with parentally reported reactions were selected for further examination including a clinical interview, physical examination, allergic tests, and if necessary, oral food challenge to conclude the diagnosis of FA. The estimated prevalence of allergy in children aged 4-59 months was 0.61%, being, 1.9% in infants and 0.4% in pre-schoolers. Among the 604 patients physicians evaluated with parent-reported FA, 24 (4%) had a confirmed diagnosis of food allergy, and 580 (96%) were excluded in the remaining. Of these, approximately half (51/52.6%) of 97 infants and (128/48%) of 487 pre-schoolers already performed the diet exclusion suspected food for a period of time. This study shows that high overall prevalence of parental belief of current food allergy however the same was not observed in the in physician-diagnosed food allergy. The prevalence of food allergy was lower than that observed in the literature. This study alerts health professionals to the risk entailed by overestimation of cases of food allergy and unnecessary dietary exclusion, which may result in impairment in growth and development of children, especially in their first years of life. Copyright © 2016. Published by Elsevier España, S.L.U.

  10. An integral nodal variational method for multigroup criticality calculations

    International Nuclear Information System (INIS)

    Lewis, E.E.; Tsoulfanidis, N.

    2003-01-01

    An integral formulation of the variational nodal method is presented and applied to a series of benchmark critically problems. The method combines an integral transport treatment of the even-parity flux within the spatial node with an odd-parity spherical harmonics expansion of the Lagrange multipliers at the node interfaces. The response matrices that result from this formulation are compatible with those in the VARIANT code at Argonne National Laboratory. Either homogeneous or heterogeneous nodes may be employed. In general, for calculations requiring higher-order angular approximations, the integral method yields solutions with comparable accuracy while requiring substantially less CPU time and memory than the standard spherical harmonics expansion using the same spatial approximations. (author)

  11. The role of cardiac vagal tone and inhibitory control in pre-schoolers' listening comprehension.

    Science.gov (United States)

    Scrimin, Sara; Patron, Elisabetta; Florit, Elena; Palomba, Daniela; Mason, Lucia

    2017-12-01

    This study investigated the role of basal cardiac activity and inhibitory control at the beginning of the school year in predicting oral comprehension at the end of the year in pre-schoolers. Forty-three, 4-year-olds participated in the study. At the beginning of the school year children's electrocardiogram at rest was registered followed by the assessment of inhibitory control as well as verbal working memory and verbal ability. At the end of the year all children were administered a listening comprehension ability measure. A stepwise regression showed a significant effect of basal cardiac vagal tone in predicting listening comprehension together with inhibitory control and verbal ability. These results are among the first to show the predictive role of basal cardiac vagal tone and inhibitory control in pre-schoolers' oral text comprehension, and offer new insight into the association between autonomic regulation of the heart, inhibitory control, and cognitive activity at a young age. © 2017 Wiley Periodicals, Inc.

  12. Enhancing Allocentric Spatial Recall in Pre-schoolers through Navigational Training Programme

    Directory of Open Access Journals (Sweden)

    Maddalena Boccia

    2017-10-01

    Full Text Available Unlike for other abilities, children do not receive systematic spatial orientation training at school, even though navigational training during adulthood improves spatial skills. We investigated whether navigational training programme (NTP improved spatial orientation skills in pre-schoolers. We administered 12-week NTP to seventeen 4- to 5-year-old children (training group, TG. The TG children and 17 age-matched children (control group, CG who underwent standard didactics were tested twice before (T0 and after (T1 the NTP using tasks that tap into landmark, route and survey representations. We determined that the TG participants significantly improved their performances in the most demanding navigational task, which is the task that taps into survey representation. This improvement was significantly higher than that observed in the CG, suggesting that NTP fostered the acquisition of survey representation. Such representation is typically achieved by age seven. This finding suggests that NTP improves performance on higher-level navigational tasks in pre-schoolers.

  13. Dating Violence and Sexual Assault Prevention with African American Middle Schoolers: Does Group Gender Composition Impact Dating Violence Attitudes?

    Science.gov (United States)

    Black, Beverly M.; Weisz, Arlene N.; Jayasundara, Dheeshana S.

    2012-01-01

    A dating violence and sexual assault prevention program was presented to 396, predominately African American, middle schoolers in two inner city schools in the United States. In one school the program was offered with a same-gender group composition; in the other school, the same program was offered with mixed-gender group composition. A…

  14. Systematic approaches to data analysis from the Critical Decision Method

    Directory of Open Access Journals (Sweden)

    Martin Sedlár

    2015-01-01

    Full Text Available The aim of the present paper is to introduce how to analyse the qualitative data from the Critical Decision Method. At first, characterizing the method provides the meaningful introduction into the issue. This method used in naturalistic decision making research is one of the cognitive task analysis methods, it is based on the retrospective semistructured interview about critical incident from the work and it may be applied in various domains such as emergency services, military, transport, sport or industry. Researchers can make two types of methodological adaptation. Within-method adaptations modify the way of conducting the interviews and cross-method adaptations combine this method with other related methods. There are many decsriptions of conducting the interview, but the descriptions how the data should be analysed are rare. Some researchers use conventional approaches like content analysis, grounded theory or individual procedures with reference to the objectives of research project. Wong (2004 describes two approaches to data analysis proposed for this method of data collection, which are described and reviewed in the details. They enable systematic work with a large amount of data. The structured approach organizes the data according to an a priori analysis framework and it is suitable for clearly defined object of research. Each incident is studied separately. At first, the decision chart showing the main decision points and then the incident summary are made. These decision points are used to identify the relevant statements from the transcript, which are analysed in terms of the Recognition-Primed Decision Model. Finally, the results from all the analysed incidents are integrated. The limitation of the structured approach is it may not reveal some interesting concepts. The emergent themes approach helps to identify these concepts while maintaining a systematic framework for analysis and it is used for exploratory research design. It

  15. AREAL FEATURE MATCHING BASED ON SIMILARITY USING CRITIC METHOD

    Directory of Open Access Journals (Sweden)

    J. Kim

    2015-10-01

    Full Text Available In this paper, we propose an areal feature matching method that can be applied for many-to-many matching, which involves matching a simple entity with an aggregate of several polygons or two aggregates of several polygons with fewer user intervention. To this end, an affine transformation is applied to two datasets by using polygon pairs for which the building name is the same. Then, two datasets are overlaid with intersected polygon pairs that are selected as candidate matching pairs. If many polygons intersect at this time, we calculate the inclusion function between such polygons. When the value is more than 0.4, many of the polygons are aggregated as single polygons by using a convex hull. Finally, the shape similarity is calculated between the candidate pairs according to the linear sum of the weights computed in CRITIC method and the position similarity, shape ratio similarity, and overlap similarity. The candidate pairs for which the value of the shape similarity is more than 0.7 are determined as matching pairs. We applied the method to two geospatial datasets: the digital topographic map and the KAIS map in South Korea. As a result, the visual evaluation showed two polygons that had been well detected by using the proposed method. The statistical evaluation indicates that the proposed method is accurate when using our test dataset with a high F-measure of 0.91.

  16. Areal Feature Matching Based on Similarity Using Critic Method

    Science.gov (United States)

    Kim, J.; Yu, K.

    2015-10-01

    In this paper, we propose an areal feature matching method that can be applied for many-to-many matching, which involves matching a simple entity with an aggregate of several polygons or two aggregates of several polygons with fewer user intervention. To this end, an affine transformation is applied to two datasets by using polygon pairs for which the building name is the same. Then, two datasets are overlaid with intersected polygon pairs that are selected as candidate matching pairs. If many polygons intersect at this time, we calculate the inclusion function between such polygons. When the value is more than 0.4, many of the polygons are aggregated as single polygons by using a convex hull. Finally, the shape similarity is calculated between the candidate pairs according to the linear sum of the weights computed in CRITIC method and the position similarity, shape ratio similarity, and overlap similarity. The candidate pairs for which the value of the shape similarity is more than 0.7 are determined as matching pairs. We applied the method to two geospatial datasets: the digital topographic map and the KAIS map in South Korea. As a result, the visual evaluation showed two polygons that had been well detected by using the proposed method. The statistical evaluation indicates that the proposed method is accurate when using our test dataset with a high F-measure of 0.91.

  17. Systematic approach to critical phenomena by the extended variational method and coherent-anomaly method

    International Nuclear Information System (INIS)

    Kawashima, N.; Katori, M.; Tsallis, C.; Suzuki, M.

    1989-01-01

    A general procedure to study critical phenomena of magnetic systems is discussed. It consists of systematic series of Landau-like approximations (Extended Variational Method) and the coherent-anomaly method (CAM). As for susceptibility, the present method is equivalent to the power-series CAM theory. On the other hand, the EVM gives a set of new approximants for other physical quantities. Applications to d-dimensional Ising ferromagnets are also described. The critical points and exponents are estimated with high accuracy. (author) [pt

  18. Methods of measuring Protein Disulfide Isomerase activity: a critical overview

    Science.gov (United States)

    Watanabe, Monica; Laurindo, Francisco; Fernandes, Denise

    2014-09-01

    Protein disulfide isomerase is an essential redox chaperone from the endoplasmic reticulum (ER) and is responsible for correct disulfide bond formation in nascent proteins. PDI is also found in other cellular locations in the cell, particularly the cell surface. Overall, PDI contributes to ER and global cell redox homeostasis and signaling. The knowledge about PDI structure and function progressed substantially based on in vitro studies using recombinant PDI and chimeric proteins. In these experimental scenarios, PDI reductase and chaperone activities are readily approachable. In contrast, assays to measure PDI isomerase activity, the hallmark of PDI family, are more complex. Assessment of PDI roles in cells and tissues mainly relies on gain- or loss-of-function studies. However, there is limited information regarding correlation of experimental readouts with the distinct types of PDI activities. In this mini-review, we evaluate the main methods described for measuring the different kinds of PDI activity: thiol reductase, thiol oxidase, thiol isomerase and chaperone. We emphasize the need to use appropriate controls and the role of critical interferents (e.g., detergent, presence of reducing agents). We also discuss the translation of results from in vitro studies with purified recombinant PDI to cellular and tissue samples, with critical comments on the interpretation of results.

  19. Landslide Susceptibility Statistical Methods: A Critical and Systematic Literature Review

    Science.gov (United States)

    Mihir, Monika; Malamud, Bruce; Rossi, Mauro; Reichenbach, Paola; Ardizzone, Francesca

    2014-05-01

    Landslide susceptibility assessment, the subject of this systematic review, is aimed at understanding the spatial probability of slope failures under a set of geomorphological and environmental conditions. It is estimated that about 375 landslides that occur globally each year are fatal, with around 4600 people killed per year. Past studies have brought out the increasing cost of landslide damages which primarily can be attributed to human occupation and increased human activities in the vulnerable environments. Many scientists, to evaluate and reduce landslide risk, have made an effort to efficiently map landslide susceptibility using different statistical methods. In this paper, we do a critical and systematic landslide susceptibility literature review, in terms of the different statistical methods used. For each of a broad set of studies reviewed we note: (i) study geography region and areal extent, (ii) landslide types, (iii) inventory type and temporal period covered, (iv) mapping technique (v) thematic variables used (vi) statistical models, (vii) assessment of model skill, (viii) uncertainty assessment methods, (ix) validation methods. We then pulled out broad trends within our review of landslide susceptibility, particularly regarding the statistical methods. We found that the most common statistical methods used in the study of landslide susceptibility include logistic regression, artificial neural network, discriminant analysis and weight of evidence. Although most of the studies we reviewed assessed the model skill, very few assessed model uncertainty. In terms of geographic extent, the largest number of landslide susceptibility zonations were in Turkey, Korea, Spain, Italy and Malaysia. However, there are also many landslides and fatalities in other localities, particularly India, China, Philippines, Nepal and Indonesia, Guatemala, and Pakistan, where there are much fewer landslide susceptibility studies available in the peer-review literature. This

  20. A Critical Study of Agglomerated Multigrid Methods for Diffusion

    Science.gov (United States)

    Nishikawa, Hiroaki; Diskin, Boris; Thomas, James L.

    2011-01-01

    Agglomerated multigrid techniques used in unstructured-grid methods are studied critically for a model problem representative of laminar diffusion in the incompressible limit. The studied target-grid discretizations and discretizations used on agglomerated grids are typical of current node-centered formulations. Agglomerated multigrid convergence rates are presented using a range of two- and three-dimensional randomly perturbed unstructured grids for simple geometries with isotropic and stretched grids. Two agglomeration techniques are used within an overall topology-preserving agglomeration framework. The results show that multigrid with an inconsistent coarse-grid scheme using only the edge terms (also referred to in the literature as a thin-layer formulation) provides considerable speedup over single-grid methods but its convergence deteriorates on finer grids. Multigrid with a Galerkin coarse-grid discretization using piecewise-constant prolongation and a heuristic correction factor is slower and also grid-dependent. In contrast, grid-independent convergence rates are demonstrated for multigrid with consistent coarse-grid discretizations. Convergence rates of multigrid cycles are verified with quantitative analysis methods in which parts of the two-grid cycle are replaced by their idealized counterparts.

  1. Definition of a critical confining zone using surface geophysical methods

    International Nuclear Information System (INIS)

    Eddy-Dilek, C.A.; Hoekstra, P.; Harthill, N.; Blohm, M.; Phillips, D.R.

    1996-01-01

    Definition of the hydrogeologic framework in layered sediments of fluvial and deltaic origin is a difficult challenge for environmental characterization and remediation programs due to the lithologic and stratigraphic heterogeneities inherent in these settings. These heterogeneties often control contaminant transport and the effectiveness of remediation alternatives, Surface geophysical surveys can be cost-effective methods for characterization, but individual methods have inherent limitations in resolution and sensitivity. A synergistic approach, utilizing two geophysical survey methods was applied, to define and examine the nature and extent of a deep confining zone of regulatory importance, the Crouch Branch Confining Unit, in Coastal Plain sediments at the Savannah River Site. TDEM accurately maps the overall conductance (product of thickness and electrical conductivity) of a confining zone clay facies; from variation in conductance, changes in lithology of the conforming zone can be inferred. Shear wave seismic reflection surveys map the depth to the clay layers, and the clay layer thickness, but provides little information on the lithologic nature of the confining zone. Integrated interpretation of the combined data set (including all available borehole logs) allows for delineation of the lateral and vertical extent of clay-dominated zones, sand-dominated zones, key stratigraphic horizons, and erosional features associated with unconformities. This approach has resulted in the collection of critical information that will be used to optimize remedial system design, representing a significant cost savings to environmental restoration programs at the Savannah River Site

  2. Reliable method for fission source convergence of Monte Carlo criticality calculation with Wielandt's method

    International Nuclear Information System (INIS)

    Yamamoto, Toshihiro; Miyoshi, Yoshinori

    2004-01-01

    A new algorithm of Monte Carlo criticality calculations for implementing Wielandt's method, which is one of acceleration techniques for deterministic source iteration methods, is developed, and the algorithm can be successfully implemented into MCNP code. In this algorithm, part of fission neutrons emitted during random walk processes are tracked within the current cycle, and thus a fission source distribution used in the next cycle spread more widely. Applying this method intensifies a neutron interaction effect even in a loosely-coupled array where conventional Monte Carlo criticality methods have difficulties, and a converged fission source distribution can be obtained with fewer cycles. Computing time spent for one cycle, however, increases because of tracking fission neutrons within the current cycle, which eventually results in an increase of total computing time up to convergence. In addition, statistical fluctuations of a fission source distribution in a cycle are worsened by applying Wielandt's method to Monte Carlo criticality calculations. However, since a fission source convergence is attained with fewer source iterations, a reliable determination of convergence can easily be made even in a system with a slow convergence. This acceleration method is expected to contribute to prevention of incorrect Monte Carlo criticality calculations. (author)

  3. A Critical Analysis of the Conventionally Employed Creep Lifing Methods.

    Science.gov (United States)

    Abdallah, Zakaria; Gray, Veronica; Whittaker, Mark; Perkins, Karen

    2014-04-29

    The deformation of structural alloys presents problems for power plants and aerospace applications due to the demand for elevated temperatures for higher efficiencies and reductions in greenhouse gas emissions. The materials used in such applications experience harsh environments which may lead to deformation and failure of critical components. To avoid such catastrophic failures and also increase efficiency, future designs must utilise novel/improved alloy systems with enhanced temperature capability. In recognising this issue, a detailed understanding of creep is essential for the success of these designs by ensuring components do not experience excessive deformation which may ultimately lead to failure. To achieve this, a variety of parametric methods have been developed to quantify creep and creep fracture in high temperature applications. This study reviews a number of well-known traditionally employed creep lifing methods with some more recent approaches also included. The first section of this paper focuses on predicting the long-term creep rupture properties which is an area of interest for the power generation sector. The second section looks at pre-defined strains and the re-production of full creep curves based on available data which is pertinent to the aerospace industry where components are replaced before failure.

  4. Critical thickness for Nb nanofilm on sapphire substrate: a critical analysis using finite element method

    International Nuclear Information System (INIS)

    Kumar, Arun; Subramaniam, Anandh

    2009-01-01

    Full text: On growth beyond critical thickness, interfacial misfit dislocations partially relax the misfit strains, in epitaxially grown nanofilms. In this study the stress state and growth of nanofilms is simulated using Finite Element Method (FEM); by imposing stress-free strains, corresponding to the lattice mismatch between Nb nanofilm and Sapphire substrate. On growth of the Nb nanofilm, a triangular network of edge misfit dislocations nucleates at the (0001) Al2ο3 || (111) Nb , interface. Using a combined simulation of a coherently strained nanofilm and an edge dislocation, the equilibrium criterion for the nucleation of an edge dislocation is determined. Theoretical analyses in literature use only the component of the Burger's vector parallel to the interface, which is an erroneous description of the stress state and energetics of the system. In this investigation the full interfacial edge dislocation is simulated using standard commercially available software and comparisons are made with results available in literature to bring out the utility of the methodology

  5. Critical insights into nuclear collectivity from complementary nuclear spectroscopic methods

    Science.gov (United States)

    Garrett, P. E.; Wood, J. L.; Yates, S. W.

    2018-06-01

    Low-energy collectivity of nuclei has been, and is being, characterized in a critical manner using data from a variety of spectroscopic methods, including Coulomb excitation, β decay, inelastic scattering of charged and uncharged particles, transfer reactions, etc. In addition to level energies and spins, transition multipolarities and intensities, lifetimes, and nuclear moments are available. The totality of information from these probes must be considered in achieving an accurate vision of the excitations in nuclei and determining the applicability of nuclear models. From these data, major changes in our view of low-energy collectivity in nuclei have emerged; most notable is the demise of the long-held view of low-energy quadrupole collectivity near closed shells as due to vibrations about a spherical equilibrium shape. In this contribution, we focus on the basic predictions of the spherical harmonic vibrator limit of the Bohr Hamiltonian. Properties such as B(E2) values, quadrupole moments, E0 strengths, etc are outlined. Using the predicted properties as a guide, evidence is cited for and against the existence of vibrational states, and especially multi-phonon states, in nuclei that are, or historically were considered to be, spherical or have a nearly spherical shape in their ground state. It is found that very few of the nuclei that were identified in the last major survey seeking nearly spherical harmonic vibrators satisfy the more stringent guidelines presented herein. Details of these fundamental shifts in our view of low-energy collectivity in nuclei are presented.

  6. Critical Review of Diagnostic Methods Used in Chronic Pancreatic Disease

    Directory of Open Access Journals (Sweden)

    Ivan T Beck

    1995-01-01

    Full Text Available This paper provides a balanced assessment of the various pancreatic function tests and imaging techniques used in the differential diagnosis of chronic pancreatic disease. Function tests that study the digestive capacity of the pancreas (fat absorption of dietary lipids, fluorescein- or radiolabelled fats, bentiromide test, etc have high specificity, but very low sensitivity. This is because 90% of pancreas has to be destroyed before steatorrhea or creatorrhea occurs. Tests that directly measure pancreatic bicarbonate and protein secretion (secretin test, etc are more accurate and may detect pancreatic dysfunction even before anatomical changes occur. Measurement of pancreatic enzymes in serum or urine, or the decreased decline of serum amino acids during their incorporation into pancreatic enzymes, are not sufficiently sensitive or specific to help diagnose pancreatic disease. Sensitive and specific tumour markers are not yet available. Thus screening tests are not cost-effective - if they are negative, they do not exclude pancreatic disease; and if positive, they have to be confirmed by more specific tests. Imaging techniques are the most commonly used methods of investigation. The usefulness of abdominal survey films, barium studies, percutaneous transhepatic cholangiography, endoscopic retrograde cholangiopancreatography (ERCP, ultrasonography, computed tomographic scan, magnetic resonance imaging and endoscopic ultrasonography is critically reviewed. Most of the radiological methods can be combined with cytology or biopsy. Histology demonstrating malignancy establishes this diagnosis, but negative biopsies do not exclude malignant tumours. Presently only ERCP and endoscopic ultrasound can diagnose cancers sufficiently early to allow for possible `curative' surgery, and only endoscopic ultrasound is capable to stage tumours for the assessment of resectability.

  7. QuantCrit: Rectifying Quantitative Methods through Critical Race Theory

    Science.gov (United States)

    Garcia, Nichole M.; López, Nancy; Vélez, Verónica N.

    2018-01-01

    Critical race theory (CRT) in education centers, examines, and seeks to transform the relationship that undergirds race, racism, and power. CRT scholars have applied a critical race framework to advance research methodologies, namely qualitative interventions. Informed by this work, and 15 years later, this article reconsiders the possibilities of…

  8. Critical Realism and Statistical Methods--A Response to Nash

    Science.gov (United States)

    Scott, David

    2007-01-01

    This article offers a defence of critical realism in the face of objections Nash (2005) makes to it in a recent edition of this journal. It is argued that critical and scientific realisms are closely related and that both are opposed to statistical positivism. However, the suggestion is made that scientific realism retains (from statistical…

  9. Some problems of neutron source multiplication method for site measurement technology in nuclear critical safety

    International Nuclear Information System (INIS)

    Shi Yongqian; Zhu Qingfu; Hu Dingsheng; He Tao; Yao Shigui; Lin Shenghuo

    2004-01-01

    The paper gives experiment theory and experiment method of neutron source multiplication method for site measurement technology in the nuclear critical safety. The measured parameter by source multiplication method actually is a sub-critical with source neutron effective multiplication factor k s , but not the neutron effective multiplication factor k eff . The experiment research has been done on the uranium solution nuclear critical safety experiment assembly. The k s of different sub-criticality is measured by neutron source multiplication experiment method, and k eff of different sub-criticality, the reactivity coefficient of unit solution level, is first measured by period method, and then multiplied by difference of critical solution level and sub-critical solution level and obtained the reactivity of sub-critical solution level. The k eff finally can be extracted from reactivity formula. The effect on the nuclear critical safety and different between k eff and k s are discussed

  10. Computational methods for criticality safety analysis within the scale system

    International Nuclear Information System (INIS)

    Parks, C.V.; Petrie, L.M.; Landers, N.F.; Bucholz, J.A.

    1986-01-01

    The criticality safety analysis capabilities within the SCALE system are centered around the Monte Carlo codes KENO IV and KENO V.a, which are both included in SCALE as functional modules. The XSDRNPM-S module is also an important tool within SCALE for obtaining multiplication factors for one-dimensional system models. This paper reviews the features and modeling capabilities of these codes along with their implementation within the Criticality Safety Analysis Sequences (CSAS) of SCALE. The CSAS modules provide automated cross-section processing and user-friendly input that allow criticality safety analyses to be done in an efficient and accurate manner. 14 refs., 2 figs., 3 tabs

  11. The use of the critical path and critical chain methods in the South ...

    African Journals Online (AJOL)

    project management tool and requires a culture change in the company. Users of the critical ... Department of Engineering and Technology Management, University of Pretoria, Pretoria, ... Since its introduction in the late 1950s, the CPM has proven to be .... disadvantages are excessive implementation work, logic abuse, too.

  12. An Architecture Design Method for Critical Embedded Systems

    NARCIS (Netherlands)

    Feitosa, Daniel

    2014-01-01

    Critical embedded systems (CES) have become ubiquitous in the modern society, like in cars and energy appliances. However, besides their popularity, engineering of these systems is still particularly challenging. One of the greatest challenges in the development of such systems is their expected

  13. "Methods of Inquiry": Using Critical Thinking to Retain Students

    Science.gov (United States)

    Ahuna, Kelly H.; Tinnesz, Christine Gray; VanZile-Tamsen, Carol

    2011-01-01

    In the late 1980s a large northeastern university implemented a critical thinking course for undergraduate students. Combining insights from cognitive psychology and philosophy, this class was designed to give students concrete strategies to promote self-regulated learning and ensure academic success. The analyses in this study are based on…

  14. High schoolers masturbatory practices: their relationship to sexual intercourse and personal characteristics.

    Science.gov (United States)

    Smith, A M; Rosenthal, D A; Reichler, H

    1996-10-01

    This study examined the self-reported masturbatory experiences of high schooler and the relationships between masturbation and sexual intercourse and personal characteristics of these young people. A total of 436 suburban Australian adolescents between 15 and 18 years of age participated. Boys were more likely to report ever having masturbated (58.5%, versus 42.7%) and to have done so more frequently than girls (38.2% versus 8.7% reporting masturbating three or more times a week). While there was no significant sex difference in the age of initiation of masturbation there was some evidence that girls began masturbation earlier than boys. Whether sexual intercourse replaced or supplemented masturbation as a sexual practice could not be resolved, but there was evidence that masturbation was positively correlated with sexual self esteem. Young people whose parents provided a more open environment for the discussion of sexuality were more likely to report having masturbated, although the environment had a complex relationship with masturbatory practices as did young people's self rated physical maturity compared to their peers. A range of social and contextual factors must be explored to understand more fully this important component of young people's sexual experience.

  15. Development of pre-critical excore detector linear subchannel calibration method

    International Nuclear Information System (INIS)

    Choi, Yoo Sun; Goo, Bon Seung; Cha, Kyun Ho; Lee, Chang Seop; Kim, Yong Hee; Ahn, Chul Soo; Kim, Man Soo

    2001-01-01

    The improved pre-critical excore detector linear subchannel calibration method has been developed to improve the applicability of pre-critical calibration method. The existing calibration method does not always guarantee the accuracy of pre-critical calibration because the calibration results of the previous cycle are not reflected into the current cycle calibration. The developed method has a desirable feature that calibration error would not be propagated in the following cycles since the calibration data determined in previous cycle is incorporated in the current cycle calibration. The pre-critical excore detector linear calibration is tested for YGN unit 3 and UCN unit 3 to evaluate its characteristics and accuracy

  16. “Pre-schoolers in the playground” an outdoor physical activity intervention for children aged 18 months to 4 years old: study protocol for a pilot cluster randomised controlled trial

    Science.gov (United States)

    2013-01-01

    Background The pre-school years are considered critical for establishing healthy lifestyle behaviours such as physical activity. Levels of physical activity track through childhood into adulthood, thus establishing habitual physical activity early in life is vital. Time spent outdoors is associated with greater physical activity and playground interventions have been shown to increase physical activity in school aged children. There are few pre-school, playground-based interventions, and evaluations of these have found mixed results. A recent report published by the UK Chief Medical Officer (CMO) highlighted that new interventions to promote movement in the early years (0–5 years old) are needed. The aim of this study is to undertake a pilot cluster randomised controlled trial (RCT) of an outdoor playground-based physical activity intervention for parents and their children aged 18 months to 4 years old (“Pre-schoolers in the Playground”; PiP) and to assess the feasibility of conducting a full scale cluster RCT. The PiP intervention is grounded in behavioural theory (Social Cognitive Theory), and is in accordance with the CMO guidance for physical activity in the early years. It is informed by existing literature and data collected from focus groups with parents. Methods/Design One hundred and fifty pre-school children affiliated to 10 primary schools will be recruited. Schools will be randomised to either the PiP intervention arm or the control arm (usual practice). Children in the intervention arm will be invited to attend three 30 minute outdoor play sessions per week for 30 weeks (3 school terms) at the school. Feasibility will be assessed by examining recruitment rates, attendance, attrition, acceptability of the trial and of the PiP intervention to parents, fidelity of intervention implementation, capability and capacity for schools to deliver the intervention. Health outcomes and the feasibility of outcome measurement tools will be assessed. These

  17. How to measure comorbidity. a critical review of available methods.

    NARCIS (Netherlands)

    de Groot, V.; Beckerman, H.; Lankhorst, G.J.; Bouter, L.M.

    2003-01-01

    The object of this article was to systematically review available methods to measure comorbidity and to assess their validity and reliability. A search was made in Medline and Embase, with the keywords comorbidity and multi-morbidity, to identify articles in which a method to measure comorbidity was

  18. How to measure comorbidity. A critical review of available methods

    NARCIS (Netherlands)

    de Groot, V; Beckerman, H; Lankhorst, G J; Bouter, L M

    2003-01-01

    The object of this article was to systematically review available methods to measure comorbidity and to assess their validity and reliability. A search was made in Medline and Embase, with the keywords comorbidity and multi-morbidity, to identify articles in which a method to measure comorbidity was

  19. Critical Analysis of Methods for Integrating Economic and Environmental Indicators

    NARCIS (Netherlands)

    Huguet Ferran, Pau; Heijungs, Reinout; Vogtländer, Joost G.

    2018-01-01

    The application of environmental strategies requires scoring and evaluation methods that provide an integrated vision of the economic and environmental performance of systems. The vector optimisation, ratio and weighted addition of indicators are the three most prevalent techniques for addressing

  20. Criticism of the OPW method for band structure calculations

    International Nuclear Information System (INIS)

    Lendi, K.

    1977-01-01

    The OPW method is associated with a general eigenvalue problem of type (A - lambda B) x vector = 0, in which the matrix B and in particular its lowest eigenvalue decide upon the stability of the solutions lambda and, therefore, upon the applicability of the method which may become very questionable for heavier substances. Analytical proofs as well as explicit numerical estimates for several solids are given [pt

  1. Towards a Critical Health Equity Research Stance: Why Epistemology and Methodology Matter More Than Qualitative Methods.

    Science.gov (United States)

    Bowleg, Lisa

    2017-10-01

    Qualitative methods are not intrinsically progressive. Methods are simply tools to conduct research. Epistemology, the justification of knowledge, shapes methodology and methods, and thus is a vital starting point for a critical health equity research stance, regardless of whether the methods are qualitative, quantitative, or mixed. In line with this premise, I address four themes in this commentary. First, I criticize the ubiquitous and uncritical use of the term health disparities in U.S. public health. Next, I advocate for the increased use of qualitative methodologies-namely, photovoice and critical ethnography-that, pursuant to critical approaches, prioritize dismantling social-structural inequities as a prerequisite to health equity. Thereafter, I discuss epistemological stance and its influence on all aspects of the research process. Finally, I highlight my critical discourse analysis HIV prevention research based on individual interviews and focus groups with Black men, as an example of a critical health equity research approach.

  2. Psychosocial Quality-of-Life, Lifestyle and Adiposity: A Longitudinal Study in Pre-schoolers (Ballabeina Study).

    Science.gov (United States)

    Michels, Nathalie; Susi, Kriemler; Marques-Vidal, Pedro M; Nydegger, Andreas; Puder, Jardena J

    2016-06-01

    In obesity prevention, understanding psychosocial influences in early life is pivotal. Reviews reported contradictory results and a lack of longitudinal studies focusing on underlying lifestyle factors. This study tested whether psychosocial Quality-Of-Life (QOL) was associated with pre-schoolers' lifestyle and adiposity changes over one school year and whether lifestyle moderated the latter. It was hypothesised that QOL might not impact adiposity in everybody but that this might depend on preceding lifestyle. Longitudinal data from 291 Swiss pre-schoolers (initially 3.9-6.3 years) was available. The following measures were used in longitudinal regressions: psychosocial QOL by PedsQL, adiposity (BMI z-score, waist, fat%), diet (food frequency), sedentary time and accelerometer-based activity. Concerning lifestyle, low psychosocial QOL was only related to unfavourable changes in diet (less fruit β = 0.21 and more fat intake β = -0.28) and lower physical activity (β = 0.21). Longitudinal QOL-adiposity relations appeared only after moderation by lifestyle factors (beta-range 0.13-0.67). Low psychosocial QOL was associated with increased adiposity in children with an unhealthy diet intake or high sedentary time. By contrast, low psychosocial QOL was associated with decreasing adiposity in high fruit consumers or more physically active pre-schoolers. Results emphasise the need for testing moderation in the QOL-adiposity relation. An unhealthy diet can be a vulnerability factor and high physical activity a protective factor in QOL-related adiposity. Consequently, QOL and lifestyle should be targeted concurrently in multi-factorial obesity prevention. The environment should be an 'activity encouraging, healthy food zone' that minimises opportunities for stress-induced eating. In addition, appropriate stress coping skills should be acquired.

  3. Critical excitation method for calculating earthquake effects on nuclear plant structures: an assessment study. Technical report

    International Nuclear Information System (INIS)

    Bedrosian, B.; Barbela, M.; Drenick, R.F.; Tsirk, A.

    1980-10-01

    The critical excitation method provides a new, alternative approach to methods presently used for seismic analysis of nuclear power plant structures. The critical excitation method offers the advantages that: (1) it side-steps the assumptions regarding the probability distribution of ground motions, and (2) it does not require an artificial, and to some extent arbitrarily generated, time history of ground motion, both features to which structural integrity analyses are sensitive. Potential utility of the critical excitation method is studied from the user's viewpoint. The method is reviewed and compared with the response spectrum method used in current practice, utilizing the reactor buildings of a PWR and a BWR plant in case studies. Two types of constraints on critical excitation were considered in the study. In one case, only an intensity limit was used. In the other case, imposition of an intensity limit together with limits on the maximum acceleration and/or velocity for the critical excitation is considered

  4. Flight critical system design guidelines and validation methods

    Science.gov (United States)

    Holt, H. M.; Lupton, A. O.; Holden, D. G.

    1984-01-01

    Efforts being expended at NASA-Langley to define a validation methodology, techniques for comparing advanced systems concepts, and design guidelines for characterizing fault tolerant digital avionics are described with an emphasis on the capabilities of AIRLAB, an environmentally controlled laboratory. AIRLAB has VAX 11/750 and 11/780 computers with an aggregate of 22 Mb memory and over 650 Mb storage, interconnected at 256 kbaud. An additional computer is programmed to emulate digital devices. Ongoing work is easily accessed at user stations by either chronological or key word indexing. The CARE III program aids in analyzing the capabilities of test systems to recover from faults. An additional code, the semi-Markov unreliability program (SURE) generates upper and lower reliability bounds. The AIRLAB facility is mainly dedicated to research on designs of digital flight-critical systems which must have acceptable reliability before incorporation into aircraft control systems. The digital systems would be too costly to submit to a full battery of flight tests and must be initially examined with the AIRLAB simulation capabilities.

  5. Definition of a critical confining zone using surface geophysical methods

    International Nuclear Information System (INIS)

    Eddy-Dilek, C.A.; Looney, B.B.; Hoekstra, P.; Harthill, N.; Blohm, M.; Phillips, D.R.

    1997-01-01

    Definition of the hydrologic framework in layered sediments of fluvial and deltaic origin is a difficult challenge for environmental characterization and remediation programs due to the lithologic and stratigraphic heterogeneities inherent in these settings. The authors set out to use complementary geophysical surveys to determine the nature and extent of a deep confining unit at the Savannah River Site, South Carolina. Time Domain Electromagnetic (TDEM) soundings were used to define the electrical conductance of the clayey confining unit (aquitard), and shear-wave reflection seismic was used to define the stratigraphic framework. Based on correlations with borehole geophysical logs and sieve data, the shear-wave seismic proved capable of defining relatively fine layering in the coastal plain sediments, the upper and lower surfaces of a critical confining unit, and erosional features on the surface of the confining unit. The TDEM surveys defined the presence or absence of the clay facies of the confining unit. Moreover, by constraining the interpretation of the TDEM data with the thickness of the confining unit derived from the seismic data, the authors mapped the extent of the unit, showing where the clay is thicker, where it probably was never deposited, and where it was eroded by downcutting channels. These results have significant implications on the design and optimization of remedial systems

  6. The Fact of IgnoranceRevisiting the Socratic Method as a Tool for Teaching Critical Thinking

    Science.gov (United States)

    Romanelli, Frank

    2014-01-01

    Critical thinking, while highly valued as an ability of health care providers, remains a skill that many educators find difficult to teach. This review provides an analysis examining why current methods of teaching critical thinking to health care students (primarily medical and pharmacy students) often fail and describes a premise and potential utility of the Socratic method as a tool to teach critical thinking in health care education. PMID:25258449

  7. The fact of ignorance: revisiting the Socratic method as a tool for teaching critical thinking.

    Science.gov (United States)

    Oyler, Douglas R; Romanelli, Frank

    2014-09-15

    Critical thinking, while highly valued as an ability of health care providers, remains a skill that many educators find difficult to teach. This review provides an analysis examining why current methods of teaching critical thinking to health care students (primarily medical and pharmacy students) often fail and describes a premise and potential utility of the Socratic method as a tool to teach critical thinking in health care education.

  8. The Effectiveness of the Socratic Method in Developing Critical Thinking Skills in English Language Learners

    Science.gov (United States)

    Jensen, Roger D., Jr.

    2015-01-01

    Critical thinking skills are an important topic of the United States' education system. This study examines the literature on critical thinking skills and defines them. The study also explores one specific teaching and assessment strategy known as the Socratic Method. The five-week research study used the Socratic Method for developing critical…

  9. Critical Values for Lawshe's Content Validity Ratio: Revisiting the Original Methods of Calculation

    Science.gov (United States)

    Ayre, Colin; Scally, Andrew John

    2014-01-01

    The content validity ratio originally proposed by Lawshe is widely used to quantify content validity and yet methods used to calculate the original critical values were never reported. Methods for original calculation of critical values are suggested along with tables of exact binomial probabilities.

  10. Visual method for detecting critical damage in railway contact strips

    Science.gov (United States)

    Judek, S.; Skibicki, J.

    2018-05-01

    Ensuring an uninterrupted supply of power in the electric traction is vital for the safety of this important transport system. For this purpose, monitoring and diagnostics of the technical condition of the vehicle’s power supply elements are becoming increasingly common. This paper presents a new visual method for detecting contact strip damage, based on measurement and analysis of the movement of the overhead contact line (OCL) wire. A measurement system configuration with a 2D camera was proposed. The experimental method has shown that contact strips damage can be detected by transverse displacement signal analysis. It has been proven that the velocity signal numerically established on that basis has a comparable level in the case of identical damage, regardless of its location on the surface of the contact strip. The proposed method belongs to the group of contact-less measurements, so it does not require interference with the structure of the catenary network nor the mounting of sensors in its vicinity. Measurement of displacements of the contact wire in 2D space makes it possible to combine the functions of existing diagnostic stands assessing the correctness of the mean contact force control adjustment of the current collector with the elements of the contact strip diagnostics, which involves detecting their damage which may result in overhead contact line rupture.

  11. Method of critical power prediction based on film flow model coupled with subchannel analysis

    International Nuclear Information System (INIS)

    Tomiyama, Akio; Yokomizo, Osamu; Yoshimoto, Yuichiro; Sugawara, Satoshi.

    1988-01-01

    A new method was developed to predict critical powers for a wide variety of BWR fuel bundle designs. This method couples subchannel analysis with a liquid film flow model, instead of taking the conventional way which couples subchannel analysis with critical heat flux correlations. Flow and quality distributions in a bundle are estimated by the subchannel analysis. Using these distributions, film flow rates along fuel rods are then calculated with the film flow model. Dryout is assumed to occur where one of the film flows disappears. This method is expected to give much better adaptability to variations in geometry, heat flux, flow rate and quality distributions than the conventional methods. In order to verify the method, critical power data under BWR conditions were analyzed. Measured and calculated critical powers agreed to within ±7%. Furthermore critical power data for a tight-latticed bundle obtained by LeTourneau et al. were compared with critical powers calculated by the present method and two conventional methods, CISE correlation and subchannel analysis coupled with the CISE correlation. It was confirmed that the present method can predict critical powers more accurately than the conventional methods. (author)

  12. A survey on critical factors influencing new advertisement methods

    Directory of Open Access Journals (Sweden)

    Naser Azad

    2013-02-01

    Full Text Available Soft drink beverages are important part of many people’s foods and many prefer soft drink to water when they have dinner. Therefore, this business model can be considered as the longest lasting sector for many years and there has been not much change in these products. However, new methods of advertisement play important role for increasing market share. In this paper, we study the impact of new methods of advertisement in product development. The proposed study of this paper designs a questionnaire for one of Iranian soft drink producers, which consisted of 274 questions in Likert scale and uses factor analysis (FA to analyze the results. The study selects 250 people who live in city of Tehran, Iran and Cronbach alpha has been calculated as 0.88, which is well above the minimum desirable limit. According to our results, there were six important factors impacting in product development, including modern advertisement techniques, emotional impact, strategy of market leadership, pricing strategy, product life chain and supply entity. The most important factor loading in these six components include impact of social values, persuading unaware and uninformed customers, ability to monopolizing in production, improving pricing techniques, product life cycle and negative impact of high advertisement.

  13. Webometrics: Some Critical Issues of WWW Size Estimation Methods

    Directory of Open Access Journals (Sweden)

    Srinivasan Mohana Arunachalam

    2018-04-01

    Full Text Available The number of webpages in the Internet has increased tremendously over the last two decades however only a part of it is indexed by various search engines. This small portion is the indexable web of the Internet and can be usually reachable from a Search Engine. Search engines play a big role in making the World Wide Web accessible to the end user, and how much of the World Wide Web is accessible on the size of the search engine’s index. Researchers have proposed several ways to estimate this size of the indexable web using search engines with and without privileged access to the search engine’s database. Our report provides a summary of methods used in the last two decades to estimate the size of the World Wide Web, as well as describe how this knowledge can be used in other aspects/tasks concerning the World Wide Web.

  14. A CRITICAL ASSESSMENT OF PHOTOMETRIC REDSHIFT METHODS: A CANDELS INVESTIGATION

    International Nuclear Information System (INIS)

    Dahlen, Tomas; Ferguson, Henry C.; Mobasher, Bahram; Faber, Sandra M.; Barro, Guillermo; Guo, Yicheng; Finkelstein, Steven L.; Finlator, Kristian; Fontana, Adriano; Gruetzbauch, Ruth; Johnson, Seth; Pforr, Janine; Dickinson, Mark E.; Salvato, Mara; Wuyts, Stijn; Wiklind, Tommy; Acquaviva, Viviana; Huang, Jiasheng; Huang, Kuang-Han; Newman, Jeffrey A.

    2013-01-01

    We present results from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) photometric redshift methods investigation. In this investigation, the results from 11 participants, each using a different combination of photometric redshift code, template spectral energy distributions (SEDs), and priors, are used to examine the properties of photometric redshifts applied to deep fields with broadband multi-wavelength coverage. The photometry used includes U-band through mid-infrared filters and was derived using the TFIT method. Comparing the results, we find that there is no particular code or set of template SEDs that results in significantly better photometric redshifts compared to others. However, we find that codes producing the lowest scatter and outlier fraction utilize a training sample to optimize photometric redshifts by adding zero-point offsets, template adjusting, or adding extra smoothing errors. These results therefore stress the importance of the training procedure. We find a strong dependence of the photometric redshift accuracy on the signal-to-noise ratio of the photometry. On the other hand, we find a weak dependence of the photometric redshift scatter with redshift and galaxy color. We find that most photometric redshift codes quote redshift errors (e.g., 68% confidence intervals) that are too small compared to that expected from the spectroscopic control sample. We find that all codes show a statistically significant bias in the photometric redshifts. However, the bias is in all cases smaller than the scatter; the latter therefore dominates the errors. Finally, we find that combining results from multiple codes significantly decreases the photometric redshift scatter and outlier fraction. We discuss different ways of combining data to produce accurate photometric redshifts and error estimates

  15. The Green's function method for critical heterogeneous slabs

    International Nuclear Information System (INIS)

    Kornreich, D.E.

    1996-01-01

    Recently, the Green's Function Method (GFM) has been employed to obtain benchmark-quality results for nuclear engineering and radiative transfer calculations. This was possible because of fast and accurate calculations of the Green's function and the associated Fourier and Laplace transform inversions. Calculations have been provided in one-dimensional slab geometries for both homogeneous and heterogeneous media. A heterogeneous medium is analyzed as a series of homogeneous slabs, and Placzek's lemma is used to extend each slab to infinity. This allows use of the infinite medium Green's function (the anisotropic plane source in an infinite homogeneous medium) in the solution. To this point, a drawback of the GFM has been the limitation to media with c 1; however, mathematical solutions exist which result in oscillating Green's functions. Such calculations are briefly discussing. The limitation to media with c < 1 has been relaxed so that the Green's function may also be calculated for media with c ≥ 1. Thus, materials that contain fissionable isotopes may be modeled

  16. "Telling the Truth to Your Adopted or Foster Child: Making Sense of the Past," by Betsy Keefer and Jayne E. Schooler. Book Review.

    Science.gov (United States)

    Johnston, Patricia Irwin

    2001-01-01

    Characterizes the focus of Keefer and Schooler's book as being on talking to children who do not have contact with birthparents, while neglecting the issue of helping birth and adoptive families overcome differences inherent in what brought each to adoption. Presents chapter contents of the work. Notes that book is the best available to parents on…

  17. Organization and methods of radiation monitoring while working at nuclear critical assemblies

    International Nuclear Information System (INIS)

    Shishkin, G.V.; Komissarov, L.A.

    1980-01-01

    The organization and methods of environmental radiation monitoring while working at nuclear critical assemblies, are described. Necessary equipment for critical assemblies (signal and Ventilation systems, devices for recording accidental radiation levels of and for measuring radiation field distribution) and the personnel program of actions in case of nuclear accident. The dosimetric control at critical assemblies is usually ensured by telesystems. 8004-01 multi-channel dosimetric device is described as an example of such-system [ru

  18. Towards a Critical Health Equity Research Stance: Why Epistemology and Methodology Matter More than Qualitative Methods

    Science.gov (United States)

    Bowleg, Lisa

    2017-01-01

    Qualitative methods are not intrinsically progressive. Methods are simply tools to conduct research. Epistemology, the justification of knowledge, shapes methodology and methods, and thus is a vital starting point for a critical health equity research stance, regardless of whether the methods are qualitative, quantitative, or mixed. In line with…

  19. Technique of Critical Current Density Measurement of Bulk Superconductor with Linear Extrapolation Method

    International Nuclear Information System (INIS)

    Adi, Wisnu Ari; Sukirman, Engkir; Winatapura, Didin S.

    2000-01-01

    Technique of critical current density measurement (Jc) of HTc bulk ceramic superconductor has been performed by using linear extrapolation with four-point probes method. The measurement of critical current density HTc bulk ceramic superconductor usually causes damage in contact resistance. In order to decrease this damage factor, we introduce extrapolation method. The extrapolating data show that the critical current density Jc for YBCO (123) and BSCCO (2212) at 77 K are 10,85(6) Amp.cm - 2 and 14,46(6) Amp.cm - 2, respectively. This technique is easier, simpler, and the use of the current flow is low, so it will not damage the contact resistance of the sample. We expect that the method can give a better solution for bulk superconductor application. Key words. : superconductor, critical temperature, and critical current density

  20. A method for managing the storage of fissile materials using criticality indices

    International Nuclear Information System (INIS)

    Philbin, J.S.; Harms, G.A.

    1995-01-01

    This paper describes a method for criticality control at fissile material storage facilities. The method involves the use criticiality indices for storage canisters. The logic, methodology, and results for selected canisters are presented. A concept for an interactive computer program using the method is also introduced. The computer program can be used in real time (using precalulated data) to select a Criticality Index (CI) for a container when it is delivered to or packaged at a site. Criticality safety is assured by controlling the sum of the CIs at each storage location below a defined Emit value when containers are moved

  1. Tabular method of critical heat flux description in square packing rod bundles

    International Nuclear Information System (INIS)

    Bobkov, V.P.; Smogalev, I.P.

    2003-01-01

    Elaborations of harnessing tabular method for the description and calculation of critical heat fluxes in square packing rod bundles are presented. The tabular method for fuel rod triangular assemblies derived from using basic table for critical heat fluxes in triangular fuel assemblies demonstrates good results. For the harnessing tabular method in square packing rod bundles correction functions reflecting specific geometry were found. Comparative evaluations of calculated values for the critical heat fluxes with experimental ones are presented. Good agreement of calculations with experiments is noted in all range of parameters [ru

  2. The Threat of Unexamined Secondary Data: A Critical Race Transformative Convergent Mixed Methods

    Science.gov (United States)

    Garcia, Nichole M.; Mayorga, Oscar J.

    2018-01-01

    This article uses a critical race theory framework to conceptualize a Critical Race Transformative Convergent Mixed Methods (CRTCMM) in education. CRTCMM is a methodology that challenges normative educational research practices by acknowledging that racism permeates educational institutions and marginalizes Communities of Color. The focus of this…

  3. Methods for Detecting Early Warnings of Critical Transitions in Time Series Illustrated Using Simulated Ecological Data

    Science.gov (United States)

    Dakos, Vasilis; Carpenter, Stephen R.; Brock, William A.; Ellison, Aaron M.; Guttal, Vishwesha; Ives, Anthony R.; Kéfi, Sonia; Livina, Valerie; Seekell, David A.; van Nes, Egbert H.; Scheffer, Marten

    2012-01-01

    Many dynamical systems, including lakes, organisms, ocean circulation patterns, or financial markets, are now thought to have tipping points where critical transitions to a contrasting state can happen. Because critical transitions can occur unexpectedly and are difficult to manage, there is a need for methods that can be used to identify when a critical transition is approaching. Recent theory shows that we can identify the proximity of a system to a critical transition using a variety of so-called ‘early warning signals’, and successful empirical examples suggest a potential for practical applicability. However, while the range of proposed methods for predicting critical transitions is rapidly expanding, opinions on their practical use differ widely, and there is no comparative study that tests the limitations of the different methods to identify approaching critical transitions using time-series data. Here, we summarize a range of currently available early warning methods and apply them to two simulated time series that are typical of systems undergoing a critical transition. In addition to a methodological guide, our work offers a practical toolbox that may be used in a wide range of fields to help detect early warning signals of critical transitions in time series data. PMID:22815897

  4. Critical path method applied to research project planning: Fire Economics Evaluation System (FEES)

    Science.gov (United States)

    Earl B. Anderson; R. Stanton Hales

    1986-01-01

    The critical path method (CPM) of network analysis (a) depicts precedence among the many activities in a project by a network diagram; (b) identifies critical activities by calculating their starting, finishing, and float times; and (c) displays possible schedules by constructing time charts. CPM was applied to the development of the Forest Service's Fire...

  5. Critical length sampling: a method to estimate the volume of downed coarse woody debris

    Science.gov (United States)

    G& #246; ran St& #229; hl; Jeffrey H. Gove; Michael S. Williams; Mark J. Ducey

    2010-01-01

    In this paper, critical length sampling for estimating the volume of downed coarse woody debris is presented. Using this method, the volume of downed wood in a stand can be estimated by summing the critical lengths of down logs included in a sample obtained using a relascope or wedge prism; typically, the instrument should be tilted 90° from its usual...

  6. Assessment of Teaching Methods and Critical Thinking in a Course for Science Majors

    Science.gov (United States)

    Speck, Angela; Ruzhitskaya, L.; Whittington, A. G.

    2014-01-01

    Ability to think critically is a key ingredient to the scientific mindset. Students who take science courses may or may not be predisposed to critical thinking - the ability to evaluate information analytically. Regardless of their initial stages, students can significantly improve their critical thinking through learning and practicing their reasoning skills, critical assessments, conducting and reflecting on observations and experiments, building their questioning and communication skills, and through the use of other techniques. While, there are several of teaching methods that may help to improve critical thinking, there are only a few assessment instruments that can help in evaluating the efficacy of these methods. Critical thinking skills and improvement in those skills are notoriously difficult to measure. Assessments that are based on multiple-choice questions demonstrate students’ final decisions but not their thinking processes. In addition, during the course of studies students may develop subject-based critical thinking while not being able to extend the skills to the general critical thinking. As such, we wanted to design and conduct a study on efficacy of several teaching methods in which we would learn how students’ improve their thinking processes within a science discipline as well as in everyday life situations. We conducted a study among 20 astronomy, physics and geology majors-- both graduate and undergraduate students-- enrolled in our Solar System Science course (mostly seniors and early graduate students) at the University of Missouri. We used the Ennis-Weir Critical Thinking Essay test to assess students’ general critical thinking and, in addition, we implemented our own subject-based critical thinking assessment. Here, we present the results of this study and share our experience on designing a subject-based critical thinking assessment instrument.

  7. Method for critical software event execution reliability in high integrity software

    Energy Technology Data Exchange (ETDEWEB)

    Kidd, M.E. [Sandia National Labs., Albuquerque, NM (United States)

    1997-11-01

    This report contains viewgraphs on a method called SEER, which provides a high level of confidence that critical software driven event execution sequences faithfully exceute in the face of transient computer architecture failures in both normal and abnormal operating environments.

  8. NEURAL NETWORKS CONTROL OF THE HYBRID POWER UNIT BASED ON THE METHOD OF ADAPTIVE CRITICS

    Directory of Open Access Journals (Sweden)

    S. Serikov

    2012-01-01

    Full Text Available The formal statement of the optimization problem of hybrid vehicle power unit control is given. Its solving by neural networks method application on the basis of adaptive critic is considered.

  9. Measurement of Critical Heat Flux Using the Transient Inverse Heat Conduction Method in Spray cooling

    International Nuclear Information System (INIS)

    Kim, Yeung Chan

    2016-01-01

    A study on the measurement of critical heat flux using the transient inverse heat conduction method in spray cooling was performed. The inverse heat conduction method estimates the surface heat flux or temperature using a measured interior temperature history. The effects of the measuring time interval and location of temperature measurement on the measurement of critical heat flux were primarily investigated. The following results were obtained. The estimated critical heat flux decreased as the time interval of temperature measurement increased. Meanwhile, the effect of measurement location on critical heat flux was not significant. It was also found, from the experimental results, that the critical superheat increased as the measurement location of thermocouple neared the heat transfer surface.

  10. Measurement of Critical Heat Flux Using the Transient Inverse Heat Conduction Method in Spray cooling

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yeung Chan [Andong Nat’l Univ., Andong (Korea, Republic of)

    2016-10-15

    A study on the measurement of critical heat flux using the transient inverse heat conduction method in spray cooling was performed. The inverse heat conduction method estimates the surface heat flux or temperature using a measured interior temperature history. The effects of the measuring time interval and location of temperature measurement on the measurement of critical heat flux were primarily investigated. The following results were obtained. The estimated critical heat flux decreased as the time interval of temperature measurement increased. Meanwhile, the effect of measurement location on critical heat flux was not significant. It was also found, from the experimental results, that the critical superheat increased as the measurement location of thermocouple neared the heat transfer surface.

  11. Critical node treatment in the analytic function expansion method for Pin Power Reconstruction

    International Nuclear Information System (INIS)

    Gao, Z.; Xu, Y.; Downar, T.

    2013-01-01

    Pin Power Reconstruction (PPR) was implemented in PARCS using the eight term analytic function expansion method (AFEN). This method has been demonstrated to be both accurate and efficient. However, similar to all the methods involving analytic functions, such as the analytic node method (ANM) and AFEN for nodal solution, the use of AFEN for PPR also has potential numerical issue with critical nodes. The conventional analytic functions are trigonometric or hyperbolic sine or cosine functions with an angular frequency proportional to buckling. For a critic al node the buckling is zero and the sine functions becomes zero, and the cosine function become unity. In this case, the eight terms of the analytic functions are no longer distinguishable from ea ch other which makes their corresponding coefficients can no longer be determined uniquely. The mode flux distribution of critical node can be linear while the conventional analytic functions can only express a uniform distribution. If there is critical or near critical node in a plane, the reconstructed pin power distribution is often be shown negative or very large values using the conventional method. In this paper, we propose a new method to avoid the numerical problem wit h critical nodes which uses modified trigonometric or hyperbolic sine functions which are the ratio of trigonometric or hyperbolic sine and its angular frequency. If there are no critical or near critical nodes present, the new pin power reconstruction method with modified analytic functions are equivalent to the conventional analytic functions. The new method is demonstrated using the L336C5 benchmark problem. (authors)

  12. Critical node treatment in the analytic function expansion method for Pin Power Reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Z. [Rice University, MS 318, 6100 Main Street, Houston, TX 77005 (United States); Xu, Y. [Argonne National Laboratory, 9700 South Case Ave., Argonne, IL 60439 (United States); Downar, T. [Department of Nuclear Engineering, University of Michigan, 2355 Bonisteel blvd., Ann Arbor, MI 48109 (United States)

    2013-07-01

    Pin Power Reconstruction (PPR) was implemented in PARCS using the eight term analytic function expansion method (AFEN). This method has been demonstrated to be both accurate and efficient. However, similar to all the methods involving analytic functions, such as the analytic node method (ANM) and AFEN for nodal solution, the use of AFEN for PPR also has potential numerical issue with critical nodes. The conventional analytic functions are trigonometric or hyperbolic sine or cosine functions with an angular frequency proportional to buckling. For a critic al node the buckling is zero and the sine functions becomes zero, and the cosine function become unity. In this case, the eight terms of the analytic functions are no longer distinguishable from ea ch other which makes their corresponding coefficients can no longer be determined uniquely. The mode flux distribution of critical node can be linear while the conventional analytic functions can only express a uniform distribution. If there is critical or near critical node in a plane, the reconstructed pin power distribution is often be shown negative or very large values using the conventional method. In this paper, we propose a new method to avoid the numerical problem wit h critical nodes which uses modified trigonometric or hyperbolic sine functions which are the ratio of trigonometric or hyperbolic sine and its angular frequency. If there are no critical or near critical nodes present, the new pin power reconstruction method with modified analytic functions are equivalent to the conventional analytic functions. The new method is demonstrated using the L336C5 benchmark problem. (authors)

  13. A reflective lens: applying critical systems thinking and visual methods to ecohealth research.

    Science.gov (United States)

    Cleland, Deborah; Wyborn, Carina

    2010-12-01

    Critical systems methodology has been advocated as an effective and ethical way to engage with the uncertainty and conflicting values common to ecohealth problems. We use two contrasting case studies, coral reef management in the Philippines and national park management in Australia, to illustrate the value of critical systems approaches in exploring how people respond to environmental threats to their physical and spiritual well-being. In both cases, we used visual methods--participatory modeling and rich picturing, respectively. The critical systems methodology, with its emphasis on reflection, guided an appraisal of the research process. A discussion of these two case studies suggests that visual methods can be usefully applied within a critical systems framework to offer new insights into ecohealth issues across a diverse range of socio-political contexts. With this article, we hope to open up a conversation with other practitioners to expand the use of visual methods in integrated research.

  14. Estimating usual intakes mainly affects the micronutrient distribution among infants, toddlers and pre-schoolers from the 2012 Mexican National Health and Nutrition Survey.

    Science.gov (United States)

    Piernas, Carmen; Miles, Donna R; Deming, Denise M; Reidy, Kathleen C; Popkin, Barry M

    2016-04-01

    To compare estimates from one day with usual intake estimates to evaluate how the adjustment for within-person variability affected nutrient intake and adequacy in Mexican children. In order to obtain usual nutrient intakes, the National Cancer Institute's method was used to correct the first 24 h dietary recall collected in the entire sample (n 2045) with a second 24 h recall collected in a sub-sample (n 178). We computed estimates of one-day and usual intakes of total energy, fat, Fe, Zn and Na. 2012 Mexican National Health and Nutrition Survey. A total of 2045 children were included: 0-5·9 months old (n 182), 6-11·9 months old (n 228), 12-23·9 months old (n 537) and 24-47·9 months old (n 1098). From these, 178 provided an additional dietary recall. Although we found small or no differences in energy intake (kJ/d and kcal/d) between one-day v. usual intake means, the prevalence of inadequate and excessive energy intake decreased somewhat when using measures of usual intake relative to one day. Mean fat intake (g/d) was not different between one-day and usual intake among children >6 months old, but the prevalence of inadequate and excessive fat intake was overestimated among toddlers and pre-schoolers when using one-day intake (P6 months. There was overall low variability in energy and fat intakes but higher for micronutrients. Because the usual intake distributions are narrower, the prevalence of inadequate/excessive intakes may be biased when estimating nutrient adequacy if one day of data is used.

  15. Method for measuring the resistive transition and critical current in superconductors using pulsed current

    International Nuclear Information System (INIS)

    McGinnis, W.C.; Jones, T.E.

    1993-01-01

    A method is described for measuring the intragranular critical current of a granular superconductive material, comprising the steps of: conducting a substantially rectangular electronic pulse through said material so as to conduct a current through said material such that when said intragranular critical current of said material is exceeded, any grains present in said material are in a superconducting state when said current is less than said intragranular critical current, said material having a critical temperature; measuring said current through said material while conducting said pulse; measuring a voltage difference across said material while conducting said pulse; and determining said intragranular critical current through said material by varying said current to discern a current level at which an electrical resistance of said material increases to that of a non-superconducting state as the grains of said material transition from said superconducting to said non-superconducting state

  16. An approximate method to estimate the minimum critical mass of fissile nuclides

    International Nuclear Information System (INIS)

    Wright, R.Q.; Jordan, W.C.

    1999-01-01

    When evaluating systems in criticality safety, it is important to approximate the answer before any analysis is performed. There is currently interest in establishing the minimum critical parameters for fissile actinides. The purpose is to describe the OB-1 method for estimating the minimum critical mass for thermal systems based on one-group calculations and 235 U spheres fully reflected by water. The observation is made that for water-moderated, well-thermalized systems, the transport and leakage from the system are dominated by water. Under these conditions two fissile mixtures will have nearly the same critical volume provided the infinite media multiplication factor (k ∞ ) for the two systems is the same. This observation allows for very simple estimates of critical concentration and mass as a function of the hydrogen-to-fissile (H/X) moderation ratio by comparison to the known 235 U system

  17. A comparative study of formal methods for safety critical software in nuclear power plant

    International Nuclear Information System (INIS)

    Sohn, Se Do; Seong Poong Hyun

    2000-01-01

    The requirement of ultra high reliability of the safety critical software can not be demonstrated by testing alone. The specification based on formal method is recommended for safety system software. But there exist various kinds of formal methods, and this variety of formal method is recognized as an obstacle to the wide use of formal method. In this paper six different formal method have been applied to the same part of the functional requirements that is calculation algorithm intensive. The specification results were compared against the criteria that is derived from the characteristics that good software requirements specifications should have and regulatory body recommends to have. The application experience shows that the critical characteristics should be defined first, then appropriate method has to e selected. In our case, the Software Cost Reduction method was recommended for internal condition or calculation algorithm checking, and state chart method is recommended for the external behavioral description. (author)

  18. The Davidson Method as an alternative to power iterations for criticality calculations

    International Nuclear Information System (INIS)

    Subramanian, C.; Van Criekingen, S.; Heuveline, V.; Nataf, F.; Have, P.

    2011-01-01

    The Davidson method is implemented within the neutron transport core solver parafish to solve k-eigenvalue criticality transport problems. The parafish solver is based on domain decomposition, uses spherical harmonics (P_N method) for angular discretization, and nonconforming finite elements for spatial discretization. The Davidson method is compared to the traditional power iteration method in that context. Encouraging numerical results are obtained with both sequential and parallel calculations. (author)

  19. Study and comparison of different methods control in light water critical facility

    International Nuclear Information System (INIS)

    Michaiel, M.L.; Mahmoud, M.S.

    1980-01-01

    The control of nuclear reactors, may be studied using several control methods, such as control by rod absorbers, by inserting or removing fuel rods (moderator cavities), or by changing reflector thickness. Every method has its advantage, the comparison between these different methods and their effect on the reactivity of a reactor is the purpose of this work. A computer program is written by the authors to calculate the critical radius and worth in any case of the three precedent methods of control

  20. Methods for monitoring the initial load to critical in the fast test reactor

    International Nuclear Information System (INIS)

    Johnson, D.L.

    1975-08-01

    Conventional symmetric fuel loadings for the initial loading to critical of the Fast Test Reactor (FTR) are predicted to be more time consuming than asymmetric or trisector loadings. Potentially significant time savings can be realized by the latter, since adequate intermediate assessments of neutron multiplication can be made periodically without control rod reconnection in all trisectors. Experimental simulation of both loading schemes was carried out in the Reverse Approach to Critical (RAC) experiments in the Fast Test Reactor-Engineering Mockup Critical facility. Analyses of these experiments indicated that conventional source multiplication methods can be applied for monitoring either a symmetric or asymmetric fuel loading scheme equally well provided that detection efficiency corrections are employed. Methods for refining predictions of reactivity and count rates for the stages in a load to critical were also investigated. (auth)

  1. A simple method for determining the critical point of the soil water retention curve

    DEFF Research Database (Denmark)

    Chen, Chong; Hu, Kelin; Ren, Tusheng

    2017-01-01

    he transition point between capillary water and adsorbed water, which is the critical point Pc [defined by the critical matric potential (ψc) and the critical water content (θc)] of the soil water retention curve (SWRC), demarcates the energy and water content region where flow is dominated......, a fixed tangent line method was developed to estimate Pc as an alternative to the commonly used flexible tangent line method. The relationships between Pc, and particle-size distribution and specific surface area (SSA) were analyzed. For 27 soils with various textures, the mean RMSE of water content from...... the fixed tangent line method was 0.007 g g–1, which was slightly better than that of the flexible tangent line method. With increasing clay content or SSA, ψc was more negative initially but became less negative at clay contents above ∼30%. Increasing the silt contents resulted in more negative ψc values...

  2. The Improved Methods of Critical Component Classification for the SSCs of New NPP

    International Nuclear Information System (INIS)

    Lee, Sang Dae; Yeom, Dong Un; Hyun, Jin Woo

    2010-01-01

    Functional Importance Determination (FID) process classifies the components of a plant into four groups: Critical A, Critical B, Minor and No Impact. The output of FID can be used as the decision-making tool for maintenance work priority and the input data for preventive maintenance implementation. FID applied to new Nuclear Power Plant (NPP) can be accomplished by utilizing the function analysis results and safety significance determination results of Maintenance Rule (MR) program. Using Shin-Kori NPP as an example, this paper proposes the advanced critical component classification methods for FID utilizing MR scoping results

  3. Critical assessment of radioisotopic methods used in the evaluation of pherispheral blood flow

    International Nuclear Information System (INIS)

    Kauffman, P.; Camargo, E.E.; Wolosker, M.; Dias Neto, A.L.; Carvalho, N.; Leao, L.E.P.

    1974-01-01

    A critical analysis of the radioisotope methods for studying peripheral blood flow is made. Methods using muscle injection of tracer and other ones using both the venous and the arterial routes of injection are discussed. Emphasys in the use of hippuran- 131 I for evaluating of the peripheral circulation dynamics is given [pt

  4. A method for processing the critical zone of a carbonate stratum

    Energy Technology Data Exchange (ETDEWEB)

    Dytyuk, L T; Barsukov, A V; Bragina, O A; Kalabina, A V; Samakayev, R Kh

    1982-01-01

    A method is proposed for processing the critical zone of a carbonate stratum by pumping a carbonate rock solvent into it. It is distinguished by the fact that in order to increase the penetration depth of the solvent into the stratum by reducing the speed of interaction of the solvent, a solution of beta-phenoxyvinylphosphonic acid is pumped into the critical zone of the stratum.

  5. Application of the string method to the study of critical nuclei in capillary condensation.

    Science.gov (United States)

    Qiu, Chunyin; Qian, Tiezheng; Ren, Weiqing

    2008-10-21

    We adopt a continuum description for liquid-vapor phase transition in the framework of mean-field theory and use the string method to numerically investigate the critical nuclei for capillary condensation in a slit pore. This numerical approach allows us to determine the critical nuclei corresponding to saddle points of the grand potential function in which the chemical potential is given in the beginning. The string method locates the minimal energy path (MEP), which is the most probable transition pathway connecting two metastable/stable states in configuration space. From the MEP, the saddle point is determined and the corresponding energy barrier also obtained (for grand potential). Moreover, the MEP shows how the new phase (liquid) grows out of the old phase (vapor) along the most probable transition pathway, from the birth of a critical nucleus to its consequent expansion. Our calculations run from partial wetting to complete wetting with a variable strength of attractive wall potential. In the latter case, the string method presents a unified way for computing the critical nuclei, from film formation at solid surface to bulk condensation via liquid bridge. The present application of the string method to the numerical study of capillary condensation shows the great power of this method in evaluating the critical nuclei in various liquid-vapor phase transitions.

  6. Development of likelihood estimation method for criticality accidents of mixed oxide fuel fabrication facilities

    International Nuclear Information System (INIS)

    Tamaki, Hitoshi; Yoshida, Kazuo; Kimoto, Tatsuya; Hamaguchi, Yoshikane

    2010-01-01

    A criticality accident in a MOX fuel fabrication facility may occur depending on several parameters, such as mass inventory and plutonium enrichment. MOX handling units in the facility are designed and operated based on the double contingency principle to prevent criticality accidents. Control failures of at least two parameters are needed for the occurrence of criticality accident. To evaluate the probability of such control failures, the criticality conditions of each parameter for a specific handling unit are necessary for accident scenario analysis to be clarified quantitatively with a criticality analysis computer code. In addition to this issue, a computer-based control system for mass inventory is planned to be installed into MOX handling equipment in a commercial MOX fuel fabrication plant. The reliability analysis is another important issue in evaluating the likelihood of control failure caused by software malfunction. A likelihood estimation method for criticality accident has been developed with these issues been taken into consideration. In this paper, an example of analysis with the proposed method and the applicability of the method are also shown through a trial application to a model MOX fabrication facility. (author)

  7. An Improved Computational Method for the Calculation of Mixture Liquid-Vapor Critical Points

    Science.gov (United States)

    Dimitrakopoulos, Panagiotis; Jia, Wenlong; Li, Changjun

    2014-05-01

    Knowledge of critical points is important to determine the phase behavior of a mixture. This work proposes a reliable and accurate method in order to locate the liquid-vapor critical point of a given mixture. The theoretical model is developed from the rigorous definition of critical points, based on the SRK equation of state (SRK EoS) or alternatively, on the PR EoS. In order to solve the resulting system of nonlinear equations, an improved method is introduced into an existing Newton-Raphson algorithm, which can calculate all the variables simultaneously in each iteration step. The improvements mainly focus on the derivatives of the Jacobian matrix, on the convergence criteria, and on the damping coefficient. As a result, all equations and related conditions required for the computation of the scheme are illustrated in this paper. Finally, experimental data for the critical points of 44 mixtures are adopted in order to validate the method. For the SRK EoS, average absolute errors of the predicted critical-pressure and critical-temperature values are 123.82 kPa and 3.11 K, respectively, whereas the commercial software package Calsep PVTSIM's prediction errors are 131.02 kPa and 3.24 K. For the PR EoS, the two above mentioned average absolute errors are 129.32 kPa and 2.45 K, while the PVTSIM's errors are 137.24 kPa and 2.55 K, respectively.

  8. METHODS OF MANAGING TRAFFIC DISTRIBUTION IN INFORMATION AND COMMUNICATION NETWORKS OF CRITICAL INFRASTRUCTURE SYSTEMS

    OpenAIRE

    Kosenko, Viktor; Persiyanova, Elena; Belotskyy, Oleksiy; Malyeyeva, Olga

    2017-01-01

    The subject matter of the article is information and communication networks (ICN) of critical infrastructure systems (CIS). The goal of the work is to create methods for managing the data flows and resources of the ICN of CIS to improve the efficiency of information processing. The following tasks were solved in the article: the data flow model of multi-level ICN structure was developed, the method of adaptive distribution of data flows was developed, the method of network resource assignment...

  9. Comments on the use of the Monte Carlo method for criticality calculations

    International Nuclear Information System (INIS)

    Whitesides, G.E.

    1975-01-01

    As evidenced by recent papers given at Nuclear Criticality Safety Division meetings, the use of the Monte Carlo method has become a very popular computational tool. The ease of use has undoubtably been a primary reason for this popularity. This ease of use, however, may lead to a false sense of security when using the method. Guidance on the effective use of the method and some suggestions on how to avoid some of the pitfalls that can occur are presented

  10. Comparison of Concept Mapping and Conventional Teaching Methods on Critical Thinking Skills of Nursing Students

    Directory of Open Access Journals (Sweden)

    Masoumeh Delaram

    2017-06-01

    Full Text Available Background and Objective: Development of critical thinking and practical skills has remained a serious and considerable challenge throughout the nursing educational system in Iran. Conventional methods of teaching such as lectures as the dominant method used in higher education system is a passive style which ignores critical thinking. Therefore, the aim of this study was to compare the effect of instruction by Concept-Mapping and conventional Method on critical thinking skills of nursing students. Materials and Methods:This quasi-experimental study was carried out on 70 nursing students of Tehran Nursing and Midwifery schoolwho were selected through convenient sampling method, then were divided randomly into the two equal Experimental and Control groups. Educational content was presented in the form of Concept-Mapping in the Experimental group and Lecture,Demonstration and Practicalexercises in the control group. Data collection included a demographic information and California Critical Thinking Skills (form B questionnairewhich was completed at the beginning and at the end of the fourth week of Instructional period. Data were analyzed using SPSS software (V: 21, descriptive and analytical Statistics; at the significant level P<0.05. Results: Before the intervention, the mean of critical thinking skill score was 9.71±2.66 in concept mapping group and 9.64 ± 2.14 in conventional group and the difference was not significant (P=0.121, but after the intervention, a significant difference was found between the intervention and conventionalgroup (15.20±2.71 vs 10.25±2.06, P=0.003. Conclusion: Using Concept mapping strategy in the education of nursing students may lead to developing critical thinking skills as one of the important missions of higher education. So it is recommended to usethis method in clinical nursing education.

  11. Criticality safety analysis for plutonium dissolver using silver mediated electrolytic oxidation method

    International Nuclear Information System (INIS)

    Umeda, Miki; Sugikawa, Susumu; Nakamura, Kazuhito; Egashira, Tetsurou

    1998-08-01

    Design and construction of a plutonium dissolver using silver mediated electrolytic oxidation method are promoted in NUCEF. Criticality safety analysis for the plutonium dissolver is described in this report. The electrolytic plutonium dissolver consists of connection pipes and three pots for MOX powder supply, circulation and electrolysis. The criticality control for the dissolver is made by geometrically safe shape with mass limitation. Monte Carlo code KENO-IV using MGCL-137 library based on ENDF/B-IV was used for the criticality safety analysis for the plutonium dissolver. Considering the required size for construction and criticality safety, diameter of pot and distance between two pots were determined. On this condition, the criticality safety analysis for the plutonium dissolver with connection pipes was carried out. As the result of the criticality safety analysis, an effective neutron multiplication factor keff of 0.91 was obtained and the criticality safety of the plutonium dissolver was confirmed on the basis of criteria of ≤0.95. (author)

  12. Critical thinking instruction and technology enhanced learning from the student perspective: A mixed methods research study.

    Science.gov (United States)

    Swart, Ruth

    2017-03-01

    Critical thinking is acclaimed as a valuable asset for graduates from higher education programs. Technology has advanced in quantity and quality; recognized as a requirement of 21st century learners. A mixed methods research study was undertaken, examining undergraduate nursing student engagement with critical thinking instruction, platformed on two technology-enhanced learning environments: a classroom response system face-to-face in-class and an online discussion forum out-of-class. The Community of Inquiry framed the study capturing constructivist collaborative inquiry to support learning, and facilitate critical thinking capability. Inclusion of quantitative and qualitative data sources aimed to gather a comprehensive understanding of students' development of critical thinking and engagement with technology-enhanced learning. The findings from the students' perspectives were positive toward the inclusion of technology-enhanced learning, and use in supporting their development of critical thinking. Students considered the use of two forms of technology beneficial in meeting different needs and preferences, offering varied means to actively participate in learning. They valued critical thinking instruction being intentionally aligned with subject-specific content facilitating understanding, application, and relevance of course material. While the findings are limited to student participants, the instructional strategies and technology-enhanced learning identified as beneficial can inform course design for the development of critical thinking. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Development of a Criticality Evaluation Method Considering the Particulate Behavior of Nuclear Fuel

    International Nuclear Information System (INIS)

    Sakai, Mikio; Yamamoto, Toshihiro; Murazaki, Minoru; Miyoshi, Yoshinori

    2005-01-01

    In conventional criticality evaluations of nuclear powder systems, effects of particulate behavior were not considered. In other words, it is difficult to take into account the particle motion in the criticality evaluations. We have developed a novel criticality evaluation code to resolve this problem. The criticality evaluation code, coupling a discrete element method simulation code with a continuous-energy Monte Carlo transport code, makes it possible to study the effects of the particulate dynamics on criticality. This criticality evaluation code is applied to the mixed-oxide (MOX) fuel powder agitation process. The criticality evaluations are performed while mixing the MOX fuel powder and an additive powder in a stirred vessel to investigate the effects of the powder free surface deformation and the particulate mixture state on the effective multiplication factor. The evaluation results reveal that the effective multiplication factor decreases due to the powder boundary deformation while it increases as the mixture condition of MOX powder and Zn-St powder is close to homogeneous

  14. A critical evaluation of methods applicable to the determination of cyanides

    International Nuclear Information System (INIS)

    Pohlandt, C.; Jones, E.A.; Lee, A.F.

    1983-01-01

    A literature survey of methods suitable for the determination of cyanides in process streams and effluents is presented. Of the large number of methods published, 92 are examined in detail, emphasis being placed on the selectivity of the methods, i.e. the extent to which they enable one to distinguish between ionic cyanide and metal-cyanide complexes. Methods designed for the determination of 'total cyanide' (i.e. ionic cyanide as well as coordinated cyanide) are evaluated critically. Other aspects of the methods are also considered, such as sensitivity, accuracy, speed, and freedom from interferences

  15. A nonparametric approach to calculate critical micelle concentrations: the local polynomial regression method

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Fontan, J.L.; Costa, J.; Ruso, J.M.; Prieto, G. [Dept. of Applied Physics, Univ. of Santiago de Compostela, Santiago de Compostela (Spain); Sarmiento, F. [Dept. of Mathematics, Faculty of Informatics, Univ. of A Coruna, A Coruna (Spain)

    2004-02-01

    The application of a statistical method, the local polynomial regression method, (LPRM), based on a nonparametric estimation of the regression function to determine the critical micelle concentration (cmc) is presented. The method is extremely flexible because it does not impose any parametric model on the subjacent structure of the data but rather allows the data to speak for themselves. Good concordance of cmc values with those obtained by other methods was found for systems in which the variation of a measured physical property with concentration showed an abrupt change. When this variation was slow, discrepancies between the values obtained by LPRM and others methods were found. (orig.)

  16. Transforming criticality control methods for EBR-II fuel handling during reactor decommissioning

    International Nuclear Information System (INIS)

    Eberle, C.S.; Dean, E.M.; Angelo, P.L.

    1995-01-01

    A review of the Department of Energy (DOE) request to decommission the Experimental Breeder Reactor-II (EBR-II) was conducted in order to develop a scope of work and analysis method for performing the safety review of the facility. Evaluation of the current national standards, DOE orders, EBR-II nuclear safeguards and criticality control practices showed that a decommissioning policy for maintaining criticality safety during a long term fuel transfer process did not exist. The purpose of this research was to provide a technical basis for transforming the reactor from an instrumentation and measurement controlled system to a system that provides both physical constraint and administrative controls to prevent criticality accidents. Essentially, this was done by modifying the reactor core configuration, reactor operations procedures and system instrumentation to meet the safety practices of ANS-8.1-1983. Subcritical limits were determined by applying established liquid metal reactor methods for both the experimental and computational validations

  17. Beethoven recordings reviewed: a systematic method for mapping the content of music performance criticism.

    Science.gov (United States)

    Alessandri, Elena; Williamson, Victoria J; Eiholzer, Hubert; Williamon, Aaron

    2015-01-01

    Critical reviews offer rich data that can be used to investigate how musical experiences are conceptualized by expert listeners. However, these data also present significant challenges in terms of organization, analysis, and interpretation. This study presents a new systematic method for examining written responses to music, tested on a substantial corpus of music criticism. One hundred critical reviews of Beethoven's piano sonata recordings, published in the Gramophone between August 1934 and July 2010, were selected using in-depth data reduction (qualitative/quantitative approach). The texts were then examined using thematic analysis in order to generate a visual descriptive model of expert critical review. This model reveals how the concept of evaluation permeates critical review. It also distinguishes between two types of descriptors. The first characterizes the performance in terms of specific actions or features of the musical sound (musical parameters, technique, and energy); the second appeals to higher-order properties (artistic style, character and emotion, musical structure, communicativeness) or assumed performer qualities (understanding, intentionality, spontaneity, sensibility, control, and care). The new model provides a methodological guide and conceptual basis for future studies of critical review in any genre.

  18. A Simple Predictive Method of Critical Flicker Detection for Human Healthy Precaution

    Directory of Open Access Journals (Sweden)

    Goh Zai Peng

    2015-01-01

    Full Text Available Interharmonics and flickers have an interrelationship between each other. Based on International Electrotechnical Commission (IEC flicker standard, the critical flicker frequency for a human eye is located at 8.8 Hz. Additionally, eye strains, headaches, and in the worst case seizures may happen due to the critical flicker. Therefore, this paper introduces a worthwhile research gap on the investigation of interrelationship between the amplitudes of the interharmonics and the critical flicker for 50 Hz power system. Consequently, the significant findings obtained in this paper are the amplitudes of two particular interharmonics are able to detect the critical flicker. In this paper, the aforementioned amplitudes are detected by adaptive linear neuron (ADALINE. After that, the critical flicker is detected by substituting the aforesaid amplitudes to the formulas that have been generated in this paper accordingly. Simulation and experimental works are conducted and the accuracy of the proposed algorithm which utilizes ADALINE is similar, as compared to typical Fluke power analyzer. In a nutshell, this simple predictive method for critical flicker detection has strong potential to be applied in any human crowded places (such as offices, shopping complexes, and stadiums for human healthy precaution purpose due to its simplicity.

  19. Developing Critical Understanding in HRM Students: Using Innovative Teaching Methods to Encourage Deep Approaches to Study

    Science.gov (United States)

    Butler, Michael J. R.; Reddy, Peter

    2010-01-01

    Purpose: This paper aims to focus on developing critical understanding in human resource management (HRM) students in Aston Business School, UK. The paper reveals that innovative teaching methods encourage deep approaches to study, an indicator of students reaching their own understanding of material and ideas. This improves student employability…

  20. On solution to the problem of criticality by alternative Monte Carlo method

    International Nuclear Information System (INIS)

    Kyncl, J.

    2005-03-01

    The problem of criticality for the neutron transport equation is analyzed. The problem is transformed into an equivalent problem in a suitable set of complex functions, and the existence and uniqueness of its solution is demonstrated. The source iteration method is discussed. It is shown that the final result of the iterative process is strongly affected by the insufficient accuracy of the individual iterations. A modified method is suggested to circumvent this problem based on the theory of positive operators; the criticality problem is solved by the Monte Carlo method constructing special random process and variable so that the difference between the result and the true value can be arbitrarily small. The efficiency of this alternative method is analysed

  1. Sensitivity and uncertainty analyses applied to criticality safety validation, methods development. Volume 1

    International Nuclear Information System (INIS)

    Broadhead, B.L.; Hopper, C.M.; Childs, R.L.; Parks, C.V.

    1999-01-01

    This report presents the application of sensitivity and uncertainty (S/U) analysis methodologies to the code/data validation tasks of a criticality safety computational study. Sensitivity and uncertainty analysis methods were first developed for application to fast reactor studies in the 1970s. This work has revitalized and updated the available S/U computational capabilities such that they can be used as prototypic modules of the SCALE code system, which contains criticality analysis tools currently used by criticality safety practitioners. After complete development, simplified tools are expected to be released for general use. The S/U methods that are presented in this volume are designed to provide a formal means of establishing the range (or area) of applicability for criticality safety data validation studies. The development of parameters that are analogous to the standard trending parameters forms the key to the technique. These parameters are the D parameters, which represent the differences by group of sensitivity profiles, and the ck parameters, which are the correlation coefficients for the calculational uncertainties between systems; each set of parameters gives information relative to the similarity between pairs of selected systems, e.g., a critical experiment and a specific real-world system (the application)

  2. Developing critical practitioners: A review of teaching methods in the Bachelor of Radiography and Medical Imaging

    International Nuclear Information System (INIS)

    Mc Inerney, J.; Baird, M.

    2016-01-01

    Background: The capacity to apply critical thinking clinically is no longer an option for radiographers. Radiographers are obliged by their registration board to embrace a contemporary and integrated conceptualisation of competence, including the capacity to think critically and reflectively to resolve clinical challenges. The study examines the complexity of critical thinking, identifies the skill set and personal traits necessary to enact it practically. Methods: Third and final year radiography students' perceptions of three teaching approaches used within the undergraduate course were explored using peer reviewed survey instruments. Thematic analysis and descriptive analyses were applied to the data to make sense of the responses. Conclusions: Students are exhibiting the capacity to formulate, evaluate and revise their own work practices through critical thinking. Educational activities that have been proven effective in empowering students with the skills necessary to meet professional standards and the personal traits required to enact them should be prioritised in curricula. The study has shown that establishment of an audit trail for the educational activities in use within radiography programs can facilitate the acquisition of evidence-based and reflective practice skills amongst students. An assessment of student's perceptions of the learning activities they engage with is an important step on this trail, though a before and after measure could be applied. - Highlights: • Examines the concept of critical thinking including the personal traits required to enact it. • Reviews three teaching activities aimed at teaching critical thinking. • Assesses student perceptions of the activities in facilitating critical thinking skills. • Students who acquire critical thinking skills can undergo transformative learning. • Establishing an audit trail can ensure teaching activities are having desired effect.

  3. Application of the HN method to the critical slab problem for reflecting boundary conditions

    International Nuclear Information System (INIS)

    Tuereci, R.G.; Guelecyuez, M.C.; Kaskas, A.; Tezcan, C.

    2004-01-01

    The recently developed H N method is used to solve the critical slab problem for a slab which is surrounded by a reflector. In the special case for R=0 (the reflection coefficient) the problem reduces to the one under vacuum boundary conditions. It is shown that the method is concise and leads to fast converging numerical results. The presented numerical results are compared with the data available in literature

  4. UN Method For The Critical Slab Problem In One-Speed Neutron Transport Theory

    International Nuclear Information System (INIS)

    Oeztuerk, Hakan; Guengoer, Sueleyman

    2008-01-01

    The Chebyshev polynomial approximation (U N method) is used to solve the critical slab problem in one-speed neutron transport theory using Marshak boundary condition. The isotropic scattering kernel with the combination of forward and backward scattering is chosen for the neutrons in a uniform finite slab. Numerical results obtained by the U N method are presented in the tables together with the results obtained by the well-known P N method for comparison. It is shown that the method converges rapidly with its easily executable equations.

  5. A New Method to Detect and Correct the Critical Errors and Determine the Software-Reliability in Critical Software-System

    International Nuclear Information System (INIS)

    Krini, Ossmane; Börcsök, Josef

    2012-01-01

    In order to use electronic systems comprising of software and hardware components in safety related and high safety related applications, it is necessary to meet the Marginal risk numbers required by standards and legislative provisions. Existing processes and mathematical models are used to verify the risk numbers. On the hardware side, various accepted mathematical models, processes, and methods exist to provide the required proof. To this day, however, there are no closed models or mathematical procedures known that allow for a dependable prediction of software reliability. This work presents a method that makes a prognosis on the residual critical error number in software. Conventional models lack this ability and right now, there are no methods that forecast critical errors. The new method will show that an estimate of the residual error number of critical errors in software systems is possible by using a combination of prediction models, a ratio of critical errors, and the total error number. Subsequently, the critical expected value-function at any point in time can be derived from the new solution method, provided the detection rate has been calculated using an appropriate estimation method. Also, the presented method makes it possible to make an estimate on the critical failure rate. The approach is modelled on a real process and therefore describes two essential processes - detection and correction process.

  6. Applying the Msharpp Method in Risk Assessment for the Water Supply Critical Infrastructure Sector

    Directory of Open Access Journals (Sweden)

    Badea Dorel

    2015-06-01

    Full Text Available The paper highlights a manner to assess risks for an important sector of critical infrastructure, that of water supply, frequently regulated in international legal systems. We took into consideration the fact that risk is a problem related to the processes of decision making under conditions of uncertainty in most cases, so that by this approach we bring to the attention of critical infrastructure managers, drawing on their experience, a simple method that can be considered in a preliminary stage of risk assessment specific to water supply.

  7. Determination of the criticality parameters in heterogeneous Slab by the LTS{sub N} method

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Volnei [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Dept. de Engenharia Nuclear; Derivi, Alexandre Guimaraes [Universidade Regional Integrada (URI), Erechim, RS (Brazil)

    2001-07-01

    The goal of this work consists in the use of the LTS{sub N} method in criticality problems. This method consists basically in the application of the Laplace Transform to a system of ordinary differential equations generated by the SN approach, resulting in a system of symbolic algebraic equations dependent on the complex parameters. After solving the algebraic system by means of the Schurr and diagonalization methods, the angular fluxes are obtained performing the inverse Laplace transform, which is carried out using the Heaviside formula. This methodology is used in determination of K{sub eff}, critical thickness and the atomic density for a heterogeneous planar slab. This procedure leads the solution of eigenvalue problem to the solution of a transcendental equation. Numerical results are reported. (author)

  8. Determination of the criticality parameters in heterogeneous Slab by the LTSN method

    International Nuclear Information System (INIS)

    Borges, Volnei

    2001-01-01

    The goal of this work consists in the use of the LTS N method in criticality problems. This method consists basically in the application of the Laplace Transform to a system of ordinary differential equations generated by the SN approach, resulting in a system of symbolic algebraic equations dependent on the complex parameters. After solving the algebraic system by means of the Schurr and diagonalization methods, the angular fluxes are obtained performing the inverse Laplace transform, which is carried out using the Heaviside formula. This methodology is used in determination of K eff , critical thickness and the atomic density for a heterogeneous planar slab. This procedure leads the solution of eigenvalue problem to the solution of a transcendental equation. Numerical results are reported. (author)

  9. Determination of criticality parameters in heterogeneous planar slabs by LTSN method

    International Nuclear Information System (INIS)

    Borges, Volnei

    2000-01-01

    The goal of this work consists in the used the LTS N method in criticality problems. This method consists basically in the application of the Laplace Transform in the system of ordinary differential equations generated by the S N approach, resulting in a system of symbolic algebraic equations dependents on the complex parameters. This system is solved and, then the solution is reconstructed by the inverse of the transformed of Laplace using the Schurr and diagonalization methods and the technique of expansion of Heaviside. This methodology is used in determination of K eff , critical thickness and the atomic density for a heterogeneous planar slab. This procedure leads to the solution of eigenvalue problem to the solution of a transcendental equation. Numerical results are reported. (author)

  10. Criticality analysis of thermal reactors for two energy groups applying Monte Carlo and neutron Albedo method

    International Nuclear Information System (INIS)

    Terra, Andre Miguel Barge Pontes Torres

    2005-01-01

    The Albedo method applied to criticality calculations to nuclear reactors is characterized by following the neutron currents, allowing to make detailed analyses of the physics phenomena about interactions of the neutrons with the core-reflector set, by the determination of the probabilities of reflection, absorption, and transmission. Then, allowing to make detailed appreciations of the variation of the effective neutron multiplication factor, keff. In the present work, motivated for excellent results presented in dissertations applied to thermal reactors and shieldings, was described the methodology to Albedo method for the analysis criticality of thermal reactors by using two energy groups admitting variable core coefficients to each re-entrant current. By using the Monte Carlo KENO IV code was analyzed relation between the total fraction of neutrons absorbed in the core reactor and the fraction of neutrons that never have stayed into the reflector but were absorbed into the core. As parameters of comparison and analysis of the results obtained by the Albedo method were used one dimensional deterministic code ANISN (ANIsotropic SN transport code) and Diffusion method. The keff results determined by the Albedo method, to the type of analyzed reactor, showed excellent agreement. Thus were obtained relative errors of keff values smaller than 0,78% between the Albedo method and code ANISN. In relation to the Diffusion method were obtained errors smaller than 0,35%, showing the effectiveness of the Albedo method applied to criticality analysis. The easiness of application, simplicity and clarity of the Albedo method constitute a valuable instrument to neutronic calculations applied to nonmultiplying and multiplying media. (author)

  11. Assessing Critical Thinking Outcomes of Dental Hygiene Students Utilizing Virtual Patient Simulation: A Mixed Methods Study.

    Science.gov (United States)

    Allaire, Joanna L

    2015-09-01

    Dental hygiene educators must determine which educational practices best promote critical thinking, a quality necessary to translate knowledge into sound clinical decision making. The aim of this small pilot study was to determine whether virtual patient simulation had an effect on the critical thinking of dental hygiene students. A pretest-posttest design using the Health Science Reasoning Test was used to evaluate the critical thinking skills of senior dental hygiene students at The University of Texas School of Dentistry at Houston Dental Hygiene Program before and after their experience with computer-based patient simulation cases. Additional survey questions sought to identify the students' perceptions of whether the experience had helped develop their critical thinking skills and improved their ability to provide competent patient care. A convenience sample of 31 senior dental hygiene students completed both the pretest and posttest (81.5% of total students in that class); 30 senior dental hygiene students completed the survey on perceptions of the simulation (78.9% response rate). Although the results did not show a significant increase in mean scores, the students reported feeling that the use of virtual patients was an effective teaching method to promote critical thinking, problem-solving, and confidence in the clinical realm. The results of this pilot study may have implications to support the use of virtual patient simulations in dental hygiene education. Future research could include a larger controlled study to validate findings from this study.

  12. msiDBN: A Method of Identifying Critical Proteins in Dynamic PPI Networks

    Directory of Open Access Journals (Sweden)

    Yuan Zhang

    2014-01-01

    Full Text Available Dynamics of protein-protein interactions (PPIs reveals the recondite principles of biological processes inside a cell. Shown in a wealth of study, just a small group of proteins, rather than the majority, play more essential roles at crucial points of biological processes. This present work focuses on identifying these critical proteins exhibiting dramatic structural changes in dynamic PPI networks. First, a comprehensive way of modeling the dynamic PPIs is presented which simultaneously analyzes the activity of proteins and assembles the dynamic coregulation correlation between proteins at each time point. Second, a novel method is proposed, named msiDBN, which models a common representation of multiple PPI networks using a deep belief network framework and analyzes the reconstruction errors and the variabilities across the time courses in the biological process. Experiments were implemented on data of yeast cell cycles. We evaluated our network construction method by comparing the functional representations of the derived networks with two other traditional construction methods. The ranking results of critical proteins in msiDBN were compared with the results from the baseline methods. The results of comparison showed that msiDBN had better reconstruction rate and identified more proteins of critical value to yeast cell cycle process.

  13. Research on criticality analysis method of CNC machine tools components under fault rate correlation

    Science.gov (United States)

    Gui-xiang, Shen; Xian-zhuo, Zhao; Zhang, Ying-zhi; Chen-yu, Han

    2018-02-01

    In order to determine the key components of CNC machine tools under fault rate correlation, a system component criticality analysis method is proposed. Based on the fault mechanism analysis, the component fault relation is determined, and the adjacency matrix is introduced to describe it. Then, the fault structure relation is hierarchical by using the interpretive structure model (ISM). Assuming that the impact of the fault obeys the Markov process, the fault association matrix is described and transformed, and the Pagerank algorithm is used to determine the relative influence values, combined component fault rate under time correlation can obtain comprehensive fault rate. Based on the fault mode frequency and fault influence, the criticality of the components under the fault rate correlation is determined, and the key components are determined to provide the correct basis for equationting the reliability assurance measures. Finally, taking machining centers as an example, the effectiveness of the method is verified.

  14. Critical assessment of suitable methods used for determination of antibacterial properties at photocatalytic surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Krysa, Josef, E-mail: Josef.Krysa@vscht.cz [Institute of Chemical Technology Prague, Department of Water Technology and Environmental Engineering, Technicka 5, CZ-166 28 Prague (Czech Republic); Musilova, Eva [Institute of Chemical Technology Prague, Department of Water Technology and Environmental Engineering, Technicka 5, CZ-166 28 Prague (Czech Republic); Zita, Jiri [Institute of Chemical Technology Prague, Department of Inorganic Technology, Technicka 5, CZ-166 28 Prague (Czech Republic)

    2011-11-15

    Highlights: {yields} Methods for antibacterial activity of irradiated TiO{sub 2} films were critically assessed. {yields} As test bacteria gram negative E. coli and gram positive E. faecalis were employed. {yields} The ISO glass adhesion method is more appropriate than method with bacteria suspension. {yields} Some improvements of the ISO method were suggested. - Abstract: This work describes the development of methods necessary for antibacterial effect evaluation on irradiated TiO{sub 2} layers. Two methods using bacteria suspensions and the glass adhesion method (based on ISO 27447:2009(E)) were critically assessed and compared. As test bacteria gram negative Escherichia coli and gram positive Enterococcus faecalis were employed. The method using 50 cm{sup 3} of bacteria suspension is convenient for testing layers with strong antibacterial effect (prepared from powder photocatalysts). For the evaluation of the antibacterial effect of sol gel layers, the glass adhesion method based on the ISO is more appropriate than the method with 3 cm{sup 3} of bacteria suspension. The reason is that the later does not allow a distinction between the inhibition effect of TiO{sub 2} and UV light itself. Some improvements of the ISO method were suggested, namely the use of gelatinous pills (CCM) of bacteria, using saline solution instead of nutrient broth for bacteria suspension preparation and the application of selective media for bacteria cultivation. Decreasing the light intensity from 0.6 mW cm{sup -2} to 0.2 mW cm{sup -2} (fulfilling the requirements of the ISO) results in almost negligible effect of UV light itself, thus enabling proper testing of the antibacterial properties of TiO{sub 2} thin films.

  15. Critical assessment of suitable methods used for determination of antibacterial properties at photocatalytic surfaces

    International Nuclear Information System (INIS)

    Krysa, Josef; Musilova, Eva; Zita, Jiri

    2011-01-01

    Highlights: → Methods for antibacterial activity of irradiated TiO 2 films were critically assessed. → As test bacteria gram negative E. coli and gram positive E. faecalis were employed. → The ISO glass adhesion method is more appropriate than method with bacteria suspension. → Some improvements of the ISO method were suggested. - Abstract: This work describes the development of methods necessary for antibacterial effect evaluation on irradiated TiO 2 layers. Two methods using bacteria suspensions and the glass adhesion method (based on ISO 27447:2009(E)) were critically assessed and compared. As test bacteria gram negative Escherichia coli and gram positive Enterococcus faecalis were employed. The method using 50 cm 3 of bacteria suspension is convenient for testing layers with strong antibacterial effect (prepared from powder photocatalysts). For the evaluation of the antibacterial effect of sol gel layers, the glass adhesion method based on the ISO is more appropriate than the method with 3 cm 3 of bacteria suspension. The reason is that the later does not allow a distinction between the inhibition effect of TiO 2 and UV light itself. Some improvements of the ISO method were suggested, namely the use of gelatinous pills (CCM) of bacteria, using saline solution instead of nutrient broth for bacteria suspension preparation and the application of selective media for bacteria cultivation. Decreasing the light intensity from 0.6 mW cm -2 to 0.2 mW cm -2 (fulfilling the requirements of the ISO) results in almost negligible effect of UV light itself, thus enabling proper testing of the antibacterial properties of TiO 2 thin films.

  16. Critical Assessment of the Surface Tension determined by the Maximum Pressure Bubble Method

    OpenAIRE

    Benedetto, Franco Emmanuel; Zolotucho, Hector; Prado, Miguel Oscar

    2015-01-01

    The main factors that influence the value of surface tension of a liquid measured with the Maximum Pressure Bubble Method are critically evaluated. We present experimental results showing the effect of capillary diameter, capillary depth, bubble spheroidicity and liquid density at room temperature. We show that the decrease of bubble spheroidicity due to increase of capillary immersion depth is not sufficient to explain the deviations found in the measured surface tension values. Thus, we pro...

  17. Reliability design of a critical facility: An application of PRA methods

    International Nuclear Information System (INIS)

    Souza Vieira Neto, A.; Souza Borges, W. de

    1987-01-01

    Although a general agreement concerning the enforcement of reliability (probabilistic) design criteria for nuclear utilities is yet to be achieved. PRA methodology can still be used successfully as a project design and review tool, aimed at improving system's prospective performance or minimizing expected accident consequences. In this paper, the potential of such an application of PRA methods is examined in the special case of a critical design project currently being developed in Brazil. (orig.)

  18. A Simple Method for Determination of Critical Swimming Velocity in Swimming Flume

    OpenAIRE

    高橋, 繁浩; 若吉, 浩二; Shigehiro, TAKAHASHI; Kohji, WAKAYOSHI; 中京大学; 奈良教育大学教育学部

    2001-01-01

    The purpose of this study was to investigate a simple method for determination of critical swimming velocity (Vcri). Vcri is defined by Wakayoshi et al. (1992) as the swimming speed which could theoretically be maintained forever without exhaustion, and is expressed as the slope of a regression line between swimming distance (D) and swimming time (T) obtained at various swimming speeds. To determine Vcri, 20 well-trained swimmers were measured at several swimming speeds ranging from 1.25 m/se...

  19. A method for determining the critical strain for recrystallisation in metals

    International Nuclear Information System (INIS)

    Morais, G.A. de; Pagnano, C.A.G.; Gouvea, J.A.

    1975-01-01

    A rapid method of determining the critical strain for recrystallisation is metals is described, the results having been verified in the case of rolled pure titanium sheet. Using experimentally checked hypotheses, the plastic strain in a tensile test piece of varying cross-section could be calculated. After straining, the test piece was annealed isothermically at various temperatures, thus showing the variation of grain size with strain [pt

  20. Critical heat flux detection in rods simulating fuel elements by using dilation method

    International Nuclear Information System (INIS)

    Mesquita, A.Z.

    1993-01-01

    In out-reactor heat transfer experiments, fuel elements are often simulated by electrically heated rods. In order to prevent the heating rod from being damaged by burnout, when the critical heat flux occurs a safety system is provided which checks the axial thermal expansion of the rod. In case of sudden temperature increase, the corresponding elongation causes a fast interruption of the electrical power supply. The experiments presented here show that this method is more effective than one that uses thermocouples. (author)

  1. Illustration of the thermodynamical method of research into a critical state through the Rainford-Edwards model

    International Nuclear Information System (INIS)

    Soldatova, Je.D.; Snegyir'ov, M.G.

    2001-01-01

    The thermodynamical method for studing a critical state is illustrated by the example of critical behavior of metallic cerium in the frameworks of the improved Rainford-Edwards model. Thermodynamical stability of the model is investigated, and behavior of the whole complex of thermodynamical characteristics of the system is analyzed. It is concluded that the model has the first type of critical behaviour

  2. Critical considerations for the application of environmental DNA methods to detect aquatic species

    Science.gov (United States)

    Goldberg, Caren S.; Turner, Cameron R.; Deiner, Kristy; Klymus, Katy E.; Thomsen, Philip Francis; Murphy, Melanie A.; Spear, Stephen F.; McKee, Anna; Oyler-McCance, Sara J.; Cornman, Robert S.; Laramie, Matthew B.; Mahon, Andrew R.; Lance, Richard F.; Pilliod, David S.; Strickler, Katherine M.; Waits, Lisette P.; Fremier, Alexander K.; Takahara, Teruhiko; Herder, Jelger E.; Taberlet, Pierre

    2016-01-01

    Species detection using environmental DNA (eDNA) has tremendous potential for contributing to the understanding of the ecology and conservation of aquatic species. Detecting species using eDNA methods, rather than directly sampling the organisms, can reduce impacts on sensitive species and increase the power of field surveys for rare and elusive species. The sensitivity of eDNA methods, however, requires a heightened awareness and attention to quality assurance and quality control protocols. Additionally, the interpretation of eDNA data demands careful consideration of multiple factors. As eDNA methods have grown in application, diverse approaches have been implemented to address these issues. With interest in eDNA continuing to expand, supportive guidelines for undertaking eDNA studies are greatly needed.Environmental DNA researchers from around the world have collaborated to produce this set of guidelines and considerations for implementing eDNA methods to detect aquatic macroorganisms.Critical considerations for study design include preventing contamination in the field and the laboratory, choosing appropriate sample analysis methods, validating assays, testing for sample inhibition and following minimum reporting guidelines. Critical considerations for inference include temporal and spatial processes, limits of correlation of eDNA with abundance, uncertainty of positive and negative results, and potential sources of allochthonous DNA.We present a synthesis of knowledge at this stage for application of this new and powerful detection method.

  3. Finite element transport methods for criticality calculations - current status and potential applications

    International Nuclear Information System (INIS)

    Oliveira, C.R.E. de; Goddard, A.

    1991-01-01

    In this paper we review the current status of the finite element method applied to the solution of the neutron transport equation and we discuss its potential role in the field of criticality safety. We show that the method's ability in handling complex, irregular geometry in two- and three-dimensions coupled with its accurate solutions potentially renders it an attractive alternative to the longer-established Monte Carlo method. Details of the most favoured form of the method - that which combines finite elements in space and spherical harmonics in angle - are presented. This form of the method, which has been extensively investigated over the last decade by research groups at the University of London, has been numerically implemented in the finite element code EVENT. The code has among its main features the capability of solving fixed source eigenvalue and time-dependent complex geometry problems in two- and three-dimensions. Other features of the code include anisotropic up- and down-scatter, direct and/or adjoint solutions and access to standard data libraries. Numerical examples, ranging from simple criticality benchmark studies to the analysis of idealised three-dimensional reactor cores, are presented to demonstrate the potential of the method. (author)

  4. Critical assessment of extracellular polymeric substances extraction methods from mixed culture biomass

    DEFF Research Database (Denmark)

    Pellicer i Nàcher, Carles; Domingo Felez, Carlos; Mutlu, Ayten Gizem

    2013-01-01

    . This study presents a rigorous and critical assessment of existing physical and chemical EPS extraction methods applied to mixed-culture biomass samples (nitrifying, nitritation-anammox, and activated sludge biomass). A novel fluorescence-based method was developed and calibrated to quantify the lysis...... potential of different EPS extraction protocols. We concluded that commonly used methods to assess cell lysis (DNA concentrations or G6PDH activities in EPS extracts) do not correlate with cell viability. Furthermore, we discovered that the presence of certain chemicals in EPS extracts results in severe...... underestimation of protein and carbohydrate concentrations by using standard analytical methods. Keeping both maximum EPS extraction yields and minimal biomass lysis as criteria, it was identified a sonication-based extraction method as the best to determine and compare tightly-bound EPS fractions in different...

  5. Reinforcement learning for a biped robot based on a CPG-actor-critic method.

    Science.gov (United States)

    Nakamura, Yutaka; Mori, Takeshi; Sato, Masa-aki; Ishii, Shin

    2007-08-01

    Animals' rhythmic movements, such as locomotion, are considered to be controlled by neural circuits called central pattern generators (CPGs), which generate oscillatory signals. Motivated by this biological mechanism, studies have been conducted on the rhythmic movements controlled by CPG. As an autonomous learning framework for a CPG controller, we propose in this article a reinforcement learning method we call the "CPG-actor-critic" method. This method introduces a new architecture to the actor, and its training is roughly based on a stochastic policy gradient algorithm presented recently. We apply this method to an automatic acquisition problem of control for a biped robot. Computer simulations show that training of the CPG can be successfully performed by our method, thus allowing the biped robot to not only walk stably but also adapt to environmental changes.

  6. Finite test sets development method for test execution of safety critical software

    International Nuclear Information System (INIS)

    Shin, Sung Min; Kim, Hee Eun; Kang, Hyun Gook; Lee, Sung Jiun

    2014-01-01

    The V and V method has been utilized for this safety critical software, while SRGM has difficulties because of lack of failure occurrence data on developing phase. For the safety critical software, however, failure data cannot be gathered after installation in real plant when we consider the severe consequence. Therefore, to complement the V and V method, the test-based method need to be developed. Some studies on test-based reliability quantification method for safety critical software have been conducted in nuclear field. These studies provide useful guidance on generating test sets. An important concept of the guidance is that the test sets represent 'trajectories' (a series of successive values for the input variables of a program that occur during the operation of the software over time) in the space of inputs to the software.. Actually, the inputs to the software depends on the state of plant at that time, and these inputs form a new internal state of the software by changing values of some variables. In other words, internal state of the software at specific timing depends on the history of past inputs. Here the internal state of the software which can be changed by past inputs is named as Context of Software (CoS). In a certain CoS, a software failure occurs when a fault is triggered by some inputs. To cover the failure occurrence mechanism of a software, preceding researches insist that the inputs should be a trajectory form. However, in this approach, there are two critical problems. One is the length of the trajectory input. Input trajectory should long enough to cover failure mechanism, but the enough length is not clear. What is worse, to cover some accident scenario, one set of input should represent dozen hours of successive values. The other problem is number of tests needed. To satisfy a target reliability with reasonable confidence level, very large number of test sets are required. Development of this number of test sets is a herculean

  7. Pre-schoolers suffering from psychiatric disorders show increased cortisol secretion and poor sleep compared to healthy controls.

    Science.gov (United States)

    Hatzinger, Martin; Brand, Serge; Perren, Sonja; von Wyl, Anges; Stadelmann, Stephanie; von Klitzing, Kai; Holsboer-Trachsler, Edith

    2012-05-01

    Various studies of child cortisol secretion and sleep show a close association between poor sleep, deterioration of the HPA axis and unfavorable psychological functioning. However, there is little evidence as to whether these associations are clearly present in pre-school children suffering from psychiatric disorders. A total of 30 pre-schoolers suffering from psychiatric disorders (anxiety, adjustment disorders, emotional and attachment disorder; hyperactivity or oppositional disorder) and 35 healthy controls took part in the study. Saliva cortisol secretion was assessed both at baseline and under challenge conditions. Sleep was assessed via activity monitoring for seven consecutive days and nights, using a digital movement-measuring instrument. Parents and teachers completed questionnaires assessing children's cognitive, emotional and social functioning. The Berkeley Puppet Interview provided child-based reports of cognitive-emotional processes. Compared to healthy controls, children suffering from psychiatric disorders had much higher cortisol secretion both at baseline and under challenge conditions. Sleep was also more disturbed, and parents and teachers rated children suffering from psychiatric disorders as cognitively, emotionally and behaviorally more impaired, relative to healthy controls. Children with psychiatric disorders reported being more bullied and victimized. In five-year old children the presence of psychiatric disorders is reflected not only at psychological, social and behavioral, but also at neuroendocrine and sleep-related levels. It is likely that these children remain at increased risk for suffering from psychiatric difficulties later in life. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Effective classroom teaching methods: a critical incident technique from millennial nursing students' perspective.

    Science.gov (United States)

    Robb, Meigan

    2014-01-11

    Engaging nursing students in the classroom environment positively influences their ability to learn and apply course content to clinical practice. Students are motivated to engage in learning if their learning preferences are being met. The methods nurse educators have used with previous students in the classroom may not address the educational needs of Millennials. This manuscript presents the findings of a pilot study that used the Critical Incident Technique. The purpose of this study was to gain insight into the teaching methods that help the Millennial generation of nursing students feel engaged in the learning process. Students' perceptions of effective instructional approaches are presented in three themes. Implications for nurse educators are discussed.

  9. Analysis using formal method and testing technique for the processor module for safety-critical application

    Energy Technology Data Exchange (ETDEWEB)

    Choi, J. Y.; Choi, B. J.; Song, H. J.; Hwang, D. Y.; Song, G. H.; Lee, H. [Korea University, Seoul (Korea, Republic of)

    2008-06-15

    This research is on help develop nuclear power plant control system, through the requirement specification and verification method development. As the result of applying the test method, a test standard was obtain through test documentation writing support and a test document reflecting the standard test activities based on the test standard. The specification and verification of the pCOS system and the unified testing documentation and execution helps the entire project to progress and enable us to achieve necessary documents and technology to develop a safety critical system.

  10. Studies of neutron methods for process control and criticality surveillance of fissile material processing facilities

    International Nuclear Information System (INIS)

    Zoltowski, T.

    1988-01-01

    The development of radiochemical processes for fissile material processing and spent fuel handling need new control procedures enabling an improvement of plant throughput. This is strictly related to the implementation of continuous criticality control policy and developing reliable methods for monitoring the reactivity of radiochemical plant operations in presence of the process perturbations. Neutron methods seem to be applicable for fissile material control in some technological facilities. The measurement of epithermal neutron source multiplication with heuristic evaluation of measured data enables surveillance of anomalous reactivity enhancement leading to unsafe states. 80 refs., 47 figs., 33 tabs. (author)

  11. An efficient search method for finding the critical slip surface using the compositional Monte Carlo technique

    International Nuclear Information System (INIS)

    Goshtasbi, K.; Ahmadi, M; Naeimi, Y.

    2008-01-01

    Locating the critical slip surface and the associated minimum factor of safety are two complementary parts in a slope stability analysis. A large number of computer programs exist to solve slope stability problems. Most of these programs, however, have used inefficient and unreliable search procedures to locate the global minimum factor of safety. This paper presents an efficient and reliable method to determine the global minimum factor of safety coupled with a modified version of the Monte Carlo technique. Examples arc presented to illustrate the reliability of the proposed method

  12. Approximate solutions for the two-dimensional integral transport equation. The critically mixed methods of resolution

    International Nuclear Information System (INIS)

    Sanchez, Richard.

    1980-11-01

    This work is divided into two part the first part (note CEA-N-2165) deals with the solution of complex two-dimensional transport problems, the second one treats the critically mixed methods of resolution. These methods are applied for one-dimensional geometries with highly anisotropic scattering. In order to simplify the set of integral equation provided by the integral transport equation, the integro-differential equation is used to obtain relations that allow to lower the number of integral equation to solve; a general mathematical and numerical study is presented [fr

  13. Analysis using formal method and testing technique for the processor module for safety-critical application

    International Nuclear Information System (INIS)

    Choi, J. Y.; Choi, B. J.; Song, H. J.; Hwang, D. Y.; Song, G. H.; Lee, H.

    2008-06-01

    This research is on help develop nuclear power plant control system, through the requirement specification and verification method development. As the result of applying the test method, a test standard was obtain through test documentation writing support and a test document reflecting the standard test activities based on the test standard. The specification and verification of the pCOS system and the unified testing documentation and execution helps the entire project to progress and enable us to achieve necessary documents and technology to develop a safety critical system

  14. Numerical investigations on contactless methods for measuring critical current density in HTS: application of modified constitutive-relation method

    International Nuclear Information System (INIS)

    Kamitani, A.; Takayama, T.; Itoh, T.; Ikuno, S.

    2011-01-01

    A fast method is proposed for calculating the shielding current density in an HTS. The J-E constitutive relation is modified so as not to change the solution. A numerical code is developed on the basis of the proposed method. The permanent magnet method is successfully simulated by means of the code. A fast method has been proposed for calculating the shielding current density in a high-temperature superconducting thin film. An initial-boundary-value problem of the shielding current density cannot be always solved by means of the Runge-Kutta method even when an adaptive step-size control algorithm is incorporated to the method. In order to suppress an overflow in the algorithm, the J-E constitutive relation is modified so that its solution may satisfy the original constitutive relation. A numerical code for analyzing the shielding current density has been developed on the basis of this method and, as an application of the code, the permanent magnet method for measuring the critical current density has been investigated numerically.

  15. Methods and tools used at the IPSN for the safety assessment of critical software

    International Nuclear Information System (INIS)

    Regnier, P.; Henry, J.Y.

    1998-01-01

    A significant feature of EDF's latest 1400MWe ''N4'' generation of pressurized water reactor (PWR) is the extensive use of computerized instrumentation and control, including a fully digital system for the reactor protection function. For the safety assessment of the software driving the operation of this digital reactor protection called SPIN, IPSN has developed and implemented a set of methods and tools. Using the lessons learned from this experience, IPSN has worked at improving those methods and tools, mainly trying to make them more automatic to use, and has participated in an international assessment exercise to test some other methods and tools, either new products on the market or self-developed products. As a result of these works, this paper presents an up to date overview of the IPSN methods and tools used for the assessment of safety critical software. This assessment, which consists of an analysis of all the documentation associated with the technical specifications and of a representative set of functions, is usually carried out in five steps: (1) critical examination of the documents, (2) evaluation of the quality of the code, (3) determination of the critical software components, (4) development of test cases and choice of testing strategy, (5) dynamic analysis (consistency and robustness). This paper also presents methods and tools developed or implemented by IPSN in order to: evaluate the completeness and consistency of specification and design documents written in natural language; build a model and simulate specification or design items; evaluate the quality of the source code; carry out FMEA analysis; run the binary code and perform tests (CLAIRE); perform random or mutational tests. (author)

  16. Noise method for monitoring the sub-criticality in accelerator driven systems

    International Nuclear Information System (INIS)

    Rugama, Y.; Munoz-Cobo, J.L.; Valentine, T.E.; Mihalczo, J.T.; Perez, R.B.; Perez-Navarro, A.

    2001-01-01

    In this paper, an absolute measurements technique for the sub-criticality determination is presented. The development of ADS, requires of methods to monitor and control the sub-criticality of this kind of systems, without interfering it's normal operation mode. This method is based on the Stochastic Neutron and Photon Transport Theory developed by Munoz-Cobo et al., and which can be implemented in presently available neutron transport codes. As a by-product of the methodology a monitoring measurement technique has been developed and verified using two coupled Monte Carlo programs. The spallation collisions and the high-energy transport are simulated with LAHET. The neutrons transports with energies less than 20 MeV and the estimation of the count statistics for neutron and/or gamma ray counters in fissile systems, is simulated with MCNP-DSP. It is possible to get the kinetics parameters and the k eff value of the sub-critical system through the analysis of the counter detectors. (author)

  17. Biomass Burning Aerosol Absorption Measurements with MODIS Using the Critical Reflectance Method

    Science.gov (United States)

    Zhu, Li; Martins, Vanderlei J.; Remer, Lorraine A.

    2010-01-01

    This research uses the critical reflectance technique, a space-based remote sensing method, to measure the spatial distribution of aerosol absorption properties over land. Choosing two regions dominated by biomass burning aerosols, a series of sensitivity studies were undertaken to analyze the potential limitations of this method for the type of aerosol to be encountered in the selected study areas, and to show that the retrieved results are relatively insensitive to uncertainties in the assumptions used in the retrieval of smoke aerosol. The critical reflectance technique is then applied to Moderate Resolution Imaging Spectrometer (MODIS) data to retrieve the spectral aerosol single scattering albedo (SSA) in South African and South American 35 biomass burning events. The retrieved results were validated with collocated Aerosol Robotic Network (AERONET) retrievals. One standard deviation of mean MODIS retrievals match AERONET products to within 0.03, the magnitude of the AERONET uncertainty. The overlap of the two retrievals increases to 88%, allowing for measurement variance in the MODIS retrievals as well. The ensemble average of MODIS-derived SSA for the Amazon forest station is 0.92 at 670 nm, and 0.84-0.89 for the southern African savanna stations. The critical reflectance technique allows evaluation of the spatial variability of SSA, and shows that SSA in South America exhibits higher spatial variation than in South Africa. The accuracy of the retrieved aerosol SSA from MODIS data indicates that this product can help to better understand 44 how aerosols affect the regional and global climate.

  18. Betweenness-Based Method to Identify Critical Transmission Sectors for Supply Chain Environmental Pressure Mitigation.

    Science.gov (United States)

    Liang, Sai; Qu, Shen; Xu, Ming

    2016-02-02

    To develop industry-specific policies for mitigating environmental pressures, previous studies primarily focus on identifying sectors that directly generate large amounts of environmental pressures (a.k.a. production-based method) or indirectly drive large amounts of environmental pressures through supply chains (e.g., consumption-based method). In addition to those sectors as important environmental pressure producers or drivers, there exist sectors that are also important to environmental pressure mitigation as transmission centers. Economy-wide environmental pressure mitigation might be achieved by improving production efficiency of these key transmission sectors, that is, using less upstream inputs to produce unitary output. We develop a betweenness-based method to measure the importance of transmission sectors, borrowing the betweenness concept from network analysis. We quantify the betweenness of sectors by examining supply chain paths extracted from structural path analysis that pass through a particular sector. We take China as an example and find that those critical transmission sectors identified by betweenness-based method are not always identifiable by existing methods. This indicates that betweenness-based method can provide additional insights that cannot be obtained with existing methods on the roles individual sectors play in generating economy-wide environmental pressures. Betweenness-based method proposed here can therefore complement existing methods for guiding sector-level environmental pressure mitigation strategies.

  19. Monte Carlo method for critical systems in infinite volume: The planar Ising model.

    Science.gov (United States)

    Herdeiro, Victor; Doyon, Benjamin

    2016-10-01

    In this paper we propose a Monte Carlo method for generating finite-domain marginals of critical distributions of statistical models in infinite volume. The algorithm corrects the problem of the long-range effects of boundaries associated to generating critical distributions on finite lattices. It uses the advantage of scale invariance combined with ideas of the renormalization group in order to construct a type of "holographic" boundary condition that encodes the presence of an infinite volume beyond it. We check the quality of the distribution obtained in the case of the planar Ising model by comparing various observables with their infinite-plane prediction. We accurately reproduce planar two-, three-, and four-point of spin and energy operators. We also define a lattice stress-energy tensor, and numerically obtain the associated conformal Ward identities and the Ising central charge.

  20. Reliability Quantification Method for Safety Critical Software Based on a Finite Test Set

    International Nuclear Information System (INIS)

    Shin, Sung Min; Kim, Hee Eun; Kang, Hyun Gook; Lee, Seung Jun

    2014-01-01

    Software inside of digitalized system have very important role because it may cause irreversible consequence and affect the whole system as common cause failure. However, test-based reliability quantification method for some safety critical software has limitations caused by difficulties in developing input sets as a form of trajectory which is series of successive values of variables. To address these limitations, this study proposed another method which conduct the test using combination of single values of variables. To substitute the trajectory form of input using combination of variables, the possible range of each variable should be identified. For this purpose, assigned range of each variable, logical relations between variables, plant dynamics under certain situation, and characteristics of obtaining information of digital device are considered. A feasibility of the proposed method was confirmed through an application to the Reactor Protection System (RPS) software trip logic

  1. Applicability of simplified methods to evaluate consequences of criticality accident using past accident data

    International Nuclear Information System (INIS)

    Nakajima, Ken

    2003-01-01

    Applicability of four simplified methods to evaluate the consequences of criticality accident was investigated. Fissions in the initial burst and total fissions were evaluated using the simplified methods and those results were compared with the past accident data. The simplified methods give the number of fissions in the initial burst as a function of solution volume; however the accident data did not show such tendency. This would be caused by the lack of accident data for the initial burst with high accuracy. For total fissions, simplified almost reproduced the upper envelope of the accidents. However several accidents, which were beyond the applicable conditions, resulted in the larger total fissions than the evaluations. In particular, the Tokai-mura accident in 1999 gave in the largest total specific fissions, because the activation of cooling system brought the relatively high power for a long time. (author)

  2. Flexible rotor balancing by the influence coefficient method: Multiple critical speeds with rigid or flexible supports

    Science.gov (United States)

    Tessarzik, J. M.

    1975-01-01

    Experimental tests were conducted to demonstrate the ability of the influence coefficient method to achieve precise balance of flexible rotors of virtually any design for operation through virtually any speed range. Various practical aspects of flexible-rotor balancing were investigated. Tests were made on a laboratory quality machine having a 122 cm (48 in.) long rotor weighing 50 kg (110 lb) and covering a speed range up to 18000 rpm. The balancing method was in every instance effective, practical, and economical and permitted safe rotor operation over the full speed range covering four rotor bending critical speeds. Improved correction weight removal methods for rotor balancing were investigated. Material removal from a rotating disk was demonstrated through application of a commercially available laser.

  3. Conditioned to eat while watching television? Low-income caregivers' perspectives on the role of snacking and television viewing among pre-schoolers.

    Science.gov (United States)

    Blaine, Rachel E; Fisher, Jennifer Orlet; Blake, Christine E; Orloski, Alexandria; Younginer, Nicholas; Bruton, Yasmeen; Ganter, Claudia; Rimm, Eric B; Geller, Alan C; Davison, Kirsten K

    2016-06-01

    Although television (TV) viewing is frequently paired with snacking among young children, little is known about the environment in which caregivers promote this behaviour. We describe low-income pre-schoolers' snacking and TV viewing habits as reported by their primary caregivers, including social/physical snacking contexts, types of snacks and caregiver rationales for offering snacks. These findings may support the development of effective messages to promote healthy child snacking. Semi-structured interviews assessed caregiver conceptualizations of pre-schoolers' snacks, purpose of snacks, snack context and snack frequency. Interviews occurred in Boston, Massachusetts and Philadelphia, Pennsylvania, USA. Forty-seven low-income multi-ethnic primary caregivers of children aged 3-5 years (92 % female, 32 % Hispanic/Latino, 34 % African American) described their child's snacking in the context of TV viewing. TV viewing and child snacking themes were described consistently across racial/ethnic groups. Caregivers described snacks offered during TV viewing as largely unhealthy. Labels for TV snacks indicated non-nutritive purposes, such as 'time out', 'enjoyment' or 'quiet.' Caregivers' primary reasons for providing snacks included child's expectations, behaviour management (e.g. to occupy child) and social time (e.g. family bonding). Some caregivers used TV to distract picky children to eat more food. Child snacking and TV viewing were contextually paired by providing child-sized furniture ('TV table') specifically for snacking. Low-income caregivers facilitate pre-schoolers' snacking and TV viewing, which are described as routine, positive and useful for non-nutritive purposes. Messages to caregivers should encourage 'snack-free' TV viewing, healthy snack options and guidance for managing children's behaviour without snacks or TV.

  4. Critical comparison between equation of motion-Green's function methods and configuration interaction methods: analysis of methods and applications

    International Nuclear Information System (INIS)

    Freed, K.F.; Herman, M.F.; Yeager, D.L.

    1980-01-01

    A description is provided of the common conceptual origins of many-body equations of motion and Green's function methods in Liouville operator formulations of the quantum mechanics of atomic and molecular electronic structure. Numerical evidence is provided to show the inadequacies of the traditional strictly perturbative approaches to these methods. Nonperturbative methods are introduced by analogy with techniques developed for handling large configuration interaction calculations and by evaluating individual matrix elements to higher accuracy. The important role of higher excitations is exhibited by the numerical calculations, and explicit comparisons are made between converged equations of motion and configuration interaction calculations for systems where a fundamental theorem requires the equality of the energy differences produced by these different approaches. (Auth.)

  5. Early warning of climate tipping points from critical slowing down: comparing methods to improve robustness

    Science.gov (United States)

    Lenton, T. M.; Livina, V. N.; Dakos, V.; Van Nes, E. H.; Scheffer, M.

    2012-01-01

    We address whether robust early warning signals can, in principle, be provided before a climate tipping point is reached, focusing on methods that seek to detect critical slowing down as a precursor of bifurcation. As a test bed, six previously analysed datasets are reconsidered, three palaeoclimate records approaching abrupt transitions at the end of the last ice age and three models of varying complexity forced through a collapse of the Atlantic thermohaline circulation. Approaches based on examining the lag-1 autocorrelation function or on detrended fluctuation analysis are applied together and compared. The effects of aggregating the data, detrending method, sliding window length and filtering bandwidth are examined. Robust indicators of critical slowing down are found prior to the abrupt warming event at the end of the Younger Dryas, but the indicators are less clear prior to the Bølling-Allerød warming, or glacial termination in Antarctica. Early warnings of thermohaline circulation collapse can be masked by inter-annual variability driven by atmospheric dynamics. However, rapidly decaying modes can be successfully filtered out by using a long bandwidth or by aggregating data. The two methods have complementary strengths and weaknesses and we recommend applying them together to improve the robustness of early warnings. PMID:22291229

  6. A comparative critical study between FMEA and FTA risk analysis methods

    Science.gov (United States)

    Cristea, G.; Constantinescu, DM

    2017-10-01

    Today there is used an overwhelming number of different risk analyses techniques with acronyms such as: FMEA (Failure Modes and Effects Analysis) and its extension FMECA (Failure Mode, Effects, and Criticality Analysis), DRBFM (Design Review by Failure Mode), FTA (Fault Tree Analysis) and and its extension ETA (Event Tree Analysis), HAZOP (Hazard & Operability Studies), HACCP (Hazard Analysis and Critical Control Points) and What-if/Checklist. However, the most used analysis techniques in the mechanical and electrical industry are FMEA and FTA. In FMEA, which is an inductive method, information about the consequences and effects of the failures is usually collected through interviews with experienced people, and with different knowledge i.e., cross-functional groups. The FMEA is used to capture potential failures/risks & impacts and prioritize them on a numeric scale called Risk Priority Number (RPN) which ranges from 1 to 1000. FTA is a deductive method i.e., a general system state is decomposed into chains of more basic events of components. The logical interrelationship of how such basic events depend on and affect each other is often described analytically in a reliability structure which can be visualized as a tree. Both methods are very time-consuming to be applied thoroughly, and this is why it is oftenly not done so. As a consequence possible failure modes may not be identified. To address these shortcomings, it is proposed to use a combination of FTA and FMEA.

  7. Cellular Neural Network Method for Critical Slab with Albedo Boundary Condition

    International Nuclear Information System (INIS)

    Pirouzmanda, A.; Hadada, K.; Suh, K. Y.

    2010-01-01

    The neutron transport problems have been studied theoretically and numerically for years. A number of researchers have studied the criticality problems of one-speed neutrons in homogeneous slabs and spheres using various methods. The Chebyshev polynomial approximation method (T N method) has lately been developed and improved for the neutron transport equation in slab geometry. The one-speed time-dependent neutron transport equation using the Cellular Neural Network (CNN) for the vacuum boundary condition has previously been solved. In this paper, we demonstrate the capacity of CNN in calculating the critical slab thickness for different boundary conditions and its variation with moments N. The architecture of the CNN has already been dealt with thoroughly. Essentially, the CNN is used to model a first-order system of the partial differential equations (PDEs). The original equations in the T N approximation are also a set of PDEs. The CNN approach lends itself to analog VLSI implementation. In this study, the CNN model is implemented using the HSpice software package

  8. Prediction of critical heat flux in fuel assemblies using a CHF table method

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Tae Hyun; Hwang, Dae Hyun; Bang, Je Geon [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Baek, Won Pil; Chang, Soon Heung [Korea Advance Institute of Science and Technology, Taejon (Korea, Republic of)

    1997-12-31

    A CHF table method has been assessed in this study for rod bundle CHF predictions. At the conceptual design stage for a new reactor, a general critical heat flux (CHF) prediction method with a wide applicable range and reasonable accuracy is essential to the thermal-hydraulic design and safety analysis. In many aspects, a CHF table method (i.e., the use of a round tube CHF table with appropriate bundle correction factors) can be a promising way to fulfill this need. So the assessment of the CHF table method has been performed with the bundle CHF data relevant to pressurized water reactors (PWRs). For comparison purposes, W-3R and EPRI-1 were also applied to the same data base. Data analysis has been conducted with the subchannel code COBRA-IV-I. The CHF table method shows the best predictions based on the direct substitution method. Improvements of the bundle correction factors, especially for the spacer grid and cold wall effects, are desirable for better predictions. Though the present assessment is somewhat limited in both fuel geometries and operating conditions, the CHF table method clearly shows potential to be a general CHF predictor. 8 refs., 3 figs., 3 tabs. (Author)

  9. Prediction of critical heat flux in fuel assemblies using a CHF table method

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Tae Hyun; Hwang, Dae Hyun; Bang, Je Geon [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Baek, Won Pil; Chang, Soon Heung [Korea Advance Institute of Science and Technology, Taejon (Korea, Republic of)

    1998-12-31

    A CHF table method has been assessed in this study for rod bundle CHF predictions. At the conceptual design stage for a new reactor, a general critical heat flux (CHF) prediction method with a wide applicable range and reasonable accuracy is essential to the thermal-hydraulic design and safety analysis. In many aspects, a CHF table method (i.e., the use of a round tube CHF table with appropriate bundle correction factors) can be a promising way to fulfill this need. So the assessment of the CHF table method has been performed with the bundle CHF data relevant to pressurized water reactors (PWRs). For comparison purposes, W-3R and EPRI-1 were also applied to the same data base. Data analysis has been conducted with the subchannel code COBRA-IV-I. The CHF table method shows the best predictions based on the direct substitution method. Improvements of the bundle correction factors, especially for the spacer grid and cold wall effects, are desirable for better predictions. Though the present assessment is somewhat limited in both fuel geometries and operating conditions, the CHF table method clearly shows potential to be a general CHF predictor. 8 refs., 3 figs., 3 tabs. (Author)

  10. SACS2: Dynamic and Formal Safety Analysis Method for Complex Safety Critical System

    International Nuclear Information System (INIS)

    Koh, Kwang Yong; Seong, Poong Hyun

    2009-01-01

    Fault tree analysis (FTA) is one of the most widely used safety analysis technique in the development of safety critical systems. However, over the years, several drawbacks of the conventional FTA have become apparent. One major drawback is that conventional FTA uses only static gates and hence can not capture dynamic behaviors of the complex system precisely. Although several attempts such as dynamic fault tree (DFT), PANDORA, formal fault tree (FFT) and so on, have been made to overcome this problem, they can not still do absolute or actual time modeling because they adapt relative time concept and can capture only sequential behaviors of the system. Second drawback of conventional FTA is its lack of rigorous semantics. Because it is informal in nature, safety analysis results heavily depend on an analyst's ability and are error-prone. Finally reasoning process which is to check whether basic events really cause top events is done manually and hence very labor-intensive and timeconsuming for the complex systems. In this paper, we propose a new safety analysis method for complex safety critical system in qualitative manner. We introduce several temporal gates based on timed computational tree logic (TCTL) which can represent quantitative notion of time. Then, we translate the information of the fault trees into UPPAAL query language and the reasoning process is automatically done by UPPAAL which is the model checker for time critical system

  11. Experimental methods to validate measures of emotional state and readiness for duty in critical operations

    International Nuclear Information System (INIS)

    Weston, Louise Marie

    2007-01-01

    A recent report on criticality accidents in nuclear facilities indicates that human error played a major role in a significant number of incidents with serious consequences and that some of these human errors may be related to the emotional state of the individual. A pre-shift test to detect a deleterious emotional state could reduce the occurrence of such errors in critical operations. The effectiveness of pre-shift testing is a challenge because of the need to gather predictive data in a relatively short test period and the potential occurrence of learning effects due to a requirement for frequent testing. This report reviews the different types of reliability and validity methods and testing and statistical analysis procedures to validate measures of emotional state. The ultimate value of a validation study depends upon the percentage of human errors in critical operations that are due to the emotional state of the individual. A review of the literature to identify the most promising predictors of emotional state for this application is highly recommended

  12. An Improved Method to Control the Critical Parameters of a Multivariable Control System

    Science.gov (United States)

    Subha Hency Jims, P.; Dharmalingam, S.; Wessley, G. Jims John

    2017-10-01

    The role of control systems is to cope with the process deficiencies and the undesirable effect of the external disturbances. Most of the multivariable processes are highly iterative and complex in nature. Aircraft systems, Modern Power Plants, Refineries, Robotic systems are few such complex systems that involve numerous critical parameters that need to be monitored and controlled. Control of these important parameters is not only tedious and cumbersome but also is crucial from environmental, safety and quality perspective. In this paper, one such multivariable system, namely, a utility boiler has been considered. A modern power plant is a complex arrangement of pipework and machineries with numerous interacting control loops and support systems. In this paper, the calculation of controller parameters based on classical tuning concepts has been presented. The controller parameters thus obtained and employed has controlled the critical parameters of a boiler during fuel switching disturbances. The proposed method can be applied to control the critical parameters like elevator, aileron, rudder, elevator trim rudder and aileron trim, flap control systems of aircraft systems.

  13. Validation of the EIR LWR calculation methods for criticality assessment of storage pools

    International Nuclear Information System (INIS)

    Grimm, P.; Paratte, J.M.

    1986-11-01

    The EIR code system for the calculation of light water reactors is presented and the methods used are briefly described. The application of the system to various types of critical experiments and benchmark problems proves its good accuracy, even for heterogeneous configurations containing strong neutron absorbers such as Boral. Since the multiplication factor k eff is normally somewhat overpredicted and the spread of the results is small, this code system is validated for the calculation of storage pools, taking into account a safety margins of 1.5% on k eff . (author)

  14. V and V based Fault Estimation Method for Safety-Critical Software using BNs

    International Nuclear Information System (INIS)

    Eom, Heung Seop; Park, Gee Yong; Jang, Seung Cheol; Kang, Hyun Gook

    2011-01-01

    Quantitative software reliability measurement approaches have severe limitations in demonstrating the proper level of reliability for safety-critical software. These limitations can be overcome by using some other means of assessment. One of the promising candidates is based on the quality of the software development. Particularly in the nuclear industry, regulatory bodies in most countries do not accept the concept of quantitative goals as a sole means of meeting their regulations for the reliability of digital computers in NPPs, and use deterministic criteria for both hardware and software. The point of deterministic criteria is to assess the whole development process and its related activities during the software development life cycle for the acceptance of safety-critical software, and software V and V plays an important role in this process. In this light, we studied a V and V based fault estimation method using Bayesian Nets (BNs) to assess the reliability of safety-critical software, especially reactor protection system software in a NPP. The BNs in the study were made for an estimation of software faults and were based on the V and V frame, which governs the development of safety-critical software in the nuclear field. A case study was carried out for a reactor protection system that was developed as a part of the Korea Nuclear Instrumentation and Control System. The insight from the case study is that some important factors affecting the fault number of the target software include the residual faults in the system specification, maximum number of faults introduced in the development phase, ratio between process/function characteristic, uncertainty sizing, and fault elimination rate by inspection activities

  15. Critical care outreach referrals: a mixed-method investigative study of outcomes and experiences.

    Science.gov (United States)

    Pattison, Natalie; Eastham, Elizabeth

    2012-01-01

    To explore referrals to a critical care outreach team (CCOT), associated factors around patient management and survival to discharge, and the qualitative exploration of referral characteristics (identifying any areas for service improvement around CCOT). A single-centre mixed method study in a specialist hospital was undertaken, using an explanatory design: participant selection model. In this model, quantitative results (prospective and retrospective episode of care review, including modified early warning system (MEWS), time and delay of referral and patient outcomes for admission and survival) are further explained by qualitative (interview) data with doctors and nurses referring to outreach. Quantitative data were analysed using SPSS +17 and 19, and qualitative data were analysed using grounded theory principles. A large proportion of referrals (124/407 = 30·5%) were made by medical staff. For 97 (97/407 = 23·8%) referrals, there was a delay between the point at which patients deteriorated (as verified by retrospective record review and MEWS score triggers) and the time at when patients were referred. The average delay was 2·96 h (95% CI 1·97-3·95; SD 9·56). Timely referrals were associated with improved outcomes; however, no causal attribution can be made from the circumstances around CCOT referral. Qualitative themes included indications for referral, facilitating factors for referral, barriers to referral and consequences of referral, with an overarching core theory of reassurance. Outreach was seen as back-up and this core theory demonstrates the important, and somewhat less tangible, role outreach has in supporting ward staff to care for at-risk patients. Mapping outreach episodes of care and patient outcomes can help highlight areas for improvement. This study outlines reasons for referral and how outreach can facilitate patient pathways in critical illness. © 2011 The Authors. Nursing in Critical Care © 2011 British Association of Critical Care

  16. An abnormal situation modeling method to assist operators in safety-critical systems

    International Nuclear Information System (INIS)

    Naderpour, Mohsen; Lu, Jie; Zhang, Guangquan

    2015-01-01

    One of the main causes of accidents in safety-critical systems is human error. In order to reduce human errors in the process of handling abnormal situations that are highly complex and mentally taxing activities, operators need to be supported, from a cognitive perspective, in order to reduce their workload, stress, and the consequent error rate. Of the various cognitive activities, a correct understanding of the situation, i.e. situation awareness (SA), is a crucial factor in improving performance and reducing errors. Despite the importance of SA in decision-making in time- and safety-critical situations, the difficulty of SA modeling and assessment means that very few methods have as yet been developed. This study confronts this challenge, and develops an innovative abnormal situation modeling (ASM) method that exploits the capabilities of risk indicators, Bayesian networks and fuzzy logic systems. The risk indicators are used to identify abnormal situations, Bayesian networks are utilized to model them and a fuzzy logic system is developed to assess them. The ASM method can be used in the development of situation assessment decision support systems that underlie the achievement of SA. The performance of the ASM method is tested through a real case study at a chemical plant. - Highlights: • Bayesian networks are applied to represent operators’ mental models when confront with abnormal situations. • A fuzzy logic system is used to resemble operators’ generating assessment results for every abnormal situation. • A virtual plant user interface and a prototype based on proposed method are developed to simulate a real case

  17. A critical evaluation of worst case optimization methods for robust intensity-modulated proton therapy planning

    International Nuclear Information System (INIS)

    Fredriksson, Albin; Bokrantz, Rasmus

    2014-01-01

    Purpose: To critically evaluate and compare three worst case optimization methods that have been previously employed to generate intensity-modulated proton therapy treatment plans that are robust against systematic errors. The goal of the evaluation is to identify circumstances when the methods behave differently and to describe the mechanism behind the differences when they occur. Methods: The worst case methods optimize plans to perform as well as possible under the worst case scenario that can physically occur (composite worst case), the combination of the worst case scenarios for each objective constituent considered independently (objectivewise worst case), and the combination of the worst case scenarios for each voxel considered independently (voxelwise worst case). These three methods were assessed with respect to treatment planning for prostate under systematic setup uncertainty. An equivalence with probabilistic optimization was used to identify the scenarios that determine the outcome of the optimization. Results: If the conflict between target coverage and normal tissue sparing is small and no dose-volume histogram (DVH) constraints are present, then all three methods yield robust plans. Otherwise, they all have their shortcomings: Composite worst case led to unnecessarily low plan quality in boundary scenarios that were less difficult than the worst case ones. Objectivewise worst case generally led to nonrobust plans. Voxelwise worst case led to overly conservative plans with respect to DVH constraints, which resulted in excessive dose to normal tissue, and less sharp dose fall-off than the other two methods. Conclusions: The three worst case methods have clearly different behaviors. These behaviors can be understood from which scenarios that are active in the optimization. No particular method is superior to the others under all circumstances: composite worst case is suitable if the conflicts are not very severe or there are DVH constraints whereas

  18. A Method to Select Test Input Cases for Safety-critical Software

    International Nuclear Information System (INIS)

    Kim, Heeeun; Kang, Hyungook; Son, Hanseong

    2013-01-01

    This paper proposes a new testing methodology for effective and realistic quantification of RPS software failure probability. Software failure probability quantification is important factor in digital system safety assessment. In this study, the method for software test case generation is briefly described. The test cases generated by this method reflect the characteristics of safety-critical software and past inputs. Furthermore, the number of test cases can be reduced, but it is possible to perform exhaustive test. Aspect of software also can be reflected as failure data, so the final failure data can include the failure of software itself and external influences. Software reliability is generally accepted as the key factor in software quality since it quantifies software failures which can make a powerful system inoperative. In the KNITS (Korea Nuclear Instrumentation and Control Systems) project, the software for the fully digitalized reactor protection system (RPS) was developed under a strict procedure including unit testing and coverage measurement. Black box testing is one type of Verification and validation (V and V), in which given input values are entered and the resulting output values are compared against the expected output values. Programmable logic controllers (PLCs) were used in implementing critical systems and function block diagram (FBD) is a commonly used implementation language for PLC

  19. Resting energy expenditure in critically ill patients: Evaluation methods and clinical applications

    Directory of Open Access Journals (Sweden)

    Ana Cláudia Soncini Sanches

    Full Text Available Summary Patients on intensive care present systemic, metabolic, and hormonal alterations that may adversely affect their nutritional condition and lead to fast and important depletion of lean mass and malnutrition. Several factors and medical conditions can influence the energy expenditure (EE of critically ill patients, such as age, gender, surgery, serious infections, medications, ventilation modality, and organ dysfunction. Clinical conditions that can present with EE change include acute kidney injury, a complex disorder commonly seen in critically ill patients with manifestations that can range from minimum elevations in serum creatinine to renal failure requiring dialysis. The nutritional needs of this population are therefore complex, and determining the resting energy expenditure is essential to adjust the nutritional supply and to plan a proper diet, ensuring that energy requirements are met and avoiding complications associated with overfeeding and underfeeding. Several evaluation methods of EE in this population have been described, but all of them have limitations. Such methods include direct calorimetry, doubly labeled water, indirect calorimetry (IC, various predictive equations, and, more recently, the rule of thumb (kcal/kg of body weight. Currently, IC is considered the gold standard.

  20. Methods to measure target site penetration of antibiotics in critically ill patients.

    Science.gov (United States)

    Schwameis, Richard; Zeitlinger, Markus

    2013-02-01

    While several tools are necessary to repair a car, the engineer knows exactly which instrument he has to utilize at different parts of the broken machine. Likewise, depending on the information we are interested in, we have to choose different tools to investigate and consecutively understand the multiple aspects that are involved in pharmacokinetics of antimicrobial agents in critically ill patients. Some techniques, like blood sampling, microdialysis or positrons emission tomography (PET) will allow for obtaining continues concentration time profiles while others like bronchoalveolar lavage (BAL), biopsy or surgical tissue samples can only be used a limited number of times per subject. PET and methods based on tissue homogenization will deliver an average of the actual concentrations in intra - and extracellular compartments while investigations in isolated blood cells or microdialysis allow for more distinguished allocation of a concentration to a defined compartment. The present review aims at discussing the advantages and disadvantages of the various methods used for assessing pharmacokinetics in critically ill patients with regard to specific aspects of pharmacokinetic research and further reviews data of selected antibiotics as examples for applications of the individual techniques.

  1. A method to construct covariance files in ENDF/B format for criticality safety applications

    International Nuclear Information System (INIS)

    Naberejnev, D.G.; Smith, D.L.

    1999-01-01

    Argonne National Laboratory is providing support for a criticality safety analysis project that is being performed at Oak Ridge National Laboratory. The ANL role is to provide the covariance information needed by ORNL for this project. The ENDF/B-V evaluation is being used for this particular criticality analysis. In this evaluation, covariance information for several isotopes or elements of interest to this analysis is either not given or needs to be reconsidered. For some required materials, covariance information does not exist in ENDF/B-V: 233 U, 236 U, Zr, Mg, Gd, and Hf. For others, existing covariance information may need to be re-examined in light of the newer ENDF/B-V evaluation and recent experimental data. In this category are the following materials: 235 U, 238 U, 239 Pu, 240 Pu, 241 Pu, Fe, H, C, N, O, Al, Si, and B. A reasonable estimation of the fractional errors for various evaluated neutron cross sections from ENDF/B-V can be based on the comparisons between the major more recent evaluations including ENDF/B-VI, JENDL3.2, BROND2.2, and JEF2.2, as well as a careful examination of experimental data. A reasonable method to construct correlation matrices is proposed here. Coupling both of these considerations suggests a method to construct covariances files in ENDF/B format that can be used to express uncertainties for specific ENDF/B-V cross sections

  2. A new method for infrared imaging of air currents in and around critical hazard fume hoods

    International Nuclear Information System (INIS)

    Mulac, W.A.; McCreary, J.R.; Schmalz, H.

    1992-01-01

    A real time method of measuring and recording the efficacy of vapor containment in and around critical hazard fume hoods is being developed. An infrared camera whose response is restricted to a spectral range that overlaps a strong absorption band in a non-toxic gas is used to render real-time video images of the presence and flow of the gas. The gas, nitrous oxide, is ejected in a continuous stream in and around fume hoods that are to be certified capable of containing hazardous fumes. The principle advantage is that various scenarios of air flow displacement in and outside the hood can be easily investigated; the principle limitation is the necessity of high tracer gas concentration to obtain strong visualizations. We hope that this technique can be found to be an effective and safe method to test hoods in locations that were built before present regulations were promulgated

  3. Determining the potential independent critical pitting temperature (CPT) by a potentiostatic method using the Avesta Cell

    International Nuclear Information System (INIS)

    Arnvig, P.E.; Bisgard, A.D.

    1996-01-01

    The development of a potentiostatic method for determining the potential independent Critical Pitting Temperature (CPT) using the Avesta Cell is presented. The new potentiostatic method has been used to determine the CPT for austenitic stainless steels. The precision of the potentiostatic method of approximately ±2 C is close to that of the traditional potentiodynamic method. The time required to determine a CPT is much shorter than when using the potentiodynamic method. A CPT is obtained within 1.5 to 3 hours for each specimen. The influence of various experimental parameters such as electrochemical potential, evaluation criteria for the CPT, test area, stabilization time prior to polarization and inert gas purging is described. The lack of sensitivity towards many of these parameters as well as the high reproducibility obtained is associated with fundamentals of the pitting process. It is argued that the potential independent CPT characterizes the stable propagating pitting event as opposed to the potential dependent CPT or pitting potentials, which to a larger extent are affected by the nucleation part of the pitting process

  4. E-learning for Critical Thinking: Using Nominal Focus Group Method to Inform Software Content and Design

    Science.gov (United States)

    Parker, Steve; Mayner, Lidia; Michael Gillham, David

    2015-01-01

    Background: Undergraduate nursing students are often confused by multiple understandings of critical thinking. In response to this situation, the Critiique for critical thinking (CCT) project was implemented to provide consistent structured guidance about critical thinking. Objectives: This paper introduces Critiique software, describes initial validation of the content of this critical thinking tool and explores wider applications of the Critiique software. Materials and Methods: Critiique is flexible, authorable software that guides students step-by-step through critical appraisal of research papers. The spelling of Critiique was deliberate, so as to acquire a unique web domain name and associated logo. The CCT project involved implementation of a modified nominal focus group process with academic staff working together to establish common understandings of critical thinking. Previous work established a consensus about critical thinking in nursing and provided a starting point for the focus groups. The study was conducted at an Australian university campus with the focus group guided by open ended questions. Results: Focus group data established categories of content that academic staff identified as important for teaching critical thinking. This emerging focus group data was then used to inform modification of Critiique software so that students had access to consistent and structured guidance in relation to critical thinking and critical appraisal. Conclusions: The project succeeded in using focus group data from academics to inform software development while at the same time retaining the benefits of broader philosophical dimensions of critical thinking. PMID:26835469

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

    DEFF Research Database (Denmark)

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

    2016-01-01

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

  6. Detecting long-term growth trends using tree rings: a critical evaluation of methods.

    Science.gov (United States)

    Peters, Richard L; Groenendijk, Peter; Vlam, Mart; Zuidema, Pieter A

    2015-05-01

    Tree-ring analysis is often used to assess long-term trends in tree growth. A variety of growth-trend detection methods (GDMs) exist to disentangle age/size trends in growth from long-term growth changes. However, these detrending methods strongly differ in approach, with possible implications for their output. Here, we critically evaluate the consistency, sensitivity, reliability and accuracy of four most widely used GDMs: conservative detrending (CD) applies mathematical functions to correct for decreasing ring widths with age; basal area correction (BAC) transforms diameter into basal area growth; regional curve standardization (RCS) detrends individual tree-ring series using average age/size trends; and size class isolation (SCI) calculates growth trends within separate size classes. First, we evaluated whether these GDMs produce consistent results applied to an empirical tree-ring data set of Melia azedarach, a tropical tree species from Thailand. Three GDMs yielded similar results - a growth decline over time - but the widely used CD method did not detect any change. Second, we assessed the sensitivity (probability of correct growth-trend detection), reliability (100% minus probability of detecting false trends) and accuracy (whether the strength of imposed trends is correctly detected) of these GDMs, by applying them to simulated growth trajectories with different imposed trends: no trend, strong trends (-6% and +6% change per decade) and weak trends (-2%, +2%). All methods except CD, showed high sensitivity, reliability and accuracy to detect strong imposed trends. However, these were considerably lower in the weak or no-trend scenarios. BAC showed good sensitivity and accuracy, but low reliability, indicating uncertainty of trend detection using this method. Our study reveals that the choice of GDM influences results of growth-trend studies. We recommend applying multiple methods when analysing trends and encourage performing sensitivity and reliability

  7. Clinical course teaching in transport of critically ill patients: Small group methods

    Directory of Open Access Journals (Sweden)

    Mohammad Taghi Beigmohammadi

    2016-10-01

    Full Text Available Critically ill patient transfer is potentially risky and may be lead to morbidity and mortality. Physicians' skill is very important for safe transport. We want to evaluate the effect of clinical course teaching on the promotion of physicians' abilities in the transport of critically ill patients. In an interventional study, 320 interns, male and female, were taught about patient transfer in two groups include in one day clinical course as the small group system (n=160 and other group the lecture base learning (n=160. In the clinical course, each participant under observation of an anesthesiologist in the operation room and ICU was acquainted with mask ventilation, intubation and learned to work with a defibrillator, infusion pump, portable ventilator and pulse oximeter. In lecture group, the anesthesiologist explained the topics by video and dummy. At the end of education course, the interns’ abilities were evaluated based on checklist method and scored by the project colleague in all educational items. Three hundred twenty interns, 122 males, and 198 females; were enrolled, two groups. The clinical course training caused improvements in the interns’ knowledge and abilities in intubation and use of the defibrillator and portable ventilator vs.lecture group significantly (P<0.005. The males were better than females in laryngoscopy, but the progress of the females was significantly better than males (P=0.003. The rate of adverse events was reduced significantly after clinical course teaching (P=0.041 Clinical course teaching could promote interns' clinical competencies in the transport of critically ill patients.

  8. Methodology or method? A critical review of qualitative case study reports

    Directory of Open Access Journals (Sweden)

    Nerida Hyett

    2014-05-01

    Full Text Available Despite on-going debate about credibility, and reported limitations in comparison to other approaches, case study is an increasingly popular approach among qualitative researchers. We critically analysed the methodological descriptions of published case studies. Three high-impact qualitative methods journals were searched to locate case studies published in the past 5 years; 34 were selected for analysis. Articles were categorized as health and health services (n=12, social sciences and anthropology (n=7, or methods (n=15 case studies. The articles were reviewed using an adapted version of established criteria to determine whether adequate methodological justification was present, and if study aims, methods, and reported findings were consistent with a qualitative case study approach. Findings were grouped into five themes outlining key methodological issues: case study methodology or method, case of something particular and case selection, contextually bound case study, researcher and case interactions and triangulation, and study design inconsistent with methodology reported. Improved reporting of case studies by qualitative researchers will advance the methodology for the benefit of researchers and practitioners.

  9. Applying Critical Race Theory to Group Model Building Methods to Address Community Violence.

    Science.gov (United States)

    Frerichs, Leah; Lich, Kristen Hassmiller; Funchess, Melanie; Burrell, Marcus; Cerulli, Catherine; Bedell, Precious; White, Ann Marie

    2016-01-01

    Group model building (GMB) is an approach to building qualitative and quantitative models with stakeholders to learn about the interrelationships among multilevel factors causing complex public health problems over time. Scant literature exists on adapting this method to address public health issues that involve racial dynamics. This study's objectives are to (1) introduce GMB methods, (2) present a framework for adapting GMB to enhance cultural responsiveness, and (3) describe outcomes of adapting GMB to incorporate differences in racial socialization during a community project seeking to understand key determinants of community violence transmission. An academic-community partnership planned a 1-day session with diverse stakeholders to explore the issue of violence using GMB. We documented key questions inspired by critical race theory (CRT) and adaptations to established GMB "scripts" (i.e., published facilitation instructions). The theory's emphasis on experiential knowledge led to a narrative-based facilitation guide from which participants created causal loop diagrams. These early diagrams depict how violence is transmitted and how communities respond, based on participants' lived experiences and mental models of causation that grew to include factors associated with race. Participants found these methods useful for advancing difficult discussion. The resulting diagrams can be tested and expanded in future research, and will form the foundation for collaborative identification of solutions to build community resilience. GMB is a promising strategy that community partnerships should consider when addressing complex health issues; our experience adapting methods based on CRT is promising in its acceptability and early system insights.

  10. Methodology or method? A critical review of qualitative case study reports

    Science.gov (United States)

    Hyett, Nerida; Kenny, Amanda; Dickson-Swift, Virginia

    2014-01-01

    Despite on-going debate about credibility, and reported limitations in comparison to other approaches, case study is an increasingly popular approach among qualitative researchers. We critically analysed the methodological descriptions of published case studies. Three high-impact qualitative methods journals were searched to locate case studies published in the past 5 years; 34 were selected for analysis. Articles were categorized as health and health services (n=12), social sciences and anthropology (n=7), or methods (n=15) case studies. The articles were reviewed using an adapted version of established criteria to determine whether adequate methodological justification was present, and if study aims, methods, and reported findings were consistent with a qualitative case study approach. Findings were grouped into five themes outlining key methodological issues: case study methodology or method, case of something particular and case selection, contextually bound case study, researcher and case interactions and triangulation, and study design inconsistent with methodology reported. Improved reporting of case studies by qualitative researchers will advance the methodology for the benefit of researchers and practitioners. PMID:24809980

  11. Critical assessment of methods of protein structure prediction (CASP) - round x

    KAUST Repository

    Moult, John; Fidelis, Krzysztof; Kryshtafovych, Andriy; Schwede, Torsten; Tramontano, Anna

    2013-01-01

    This article is an introduction to the special issue of the journal PROTEINS, dedicated to the tenth Critical Assessment of Structure Prediction (CASP) experiment to assess the state of the art in protein structure modeling. The article describes the conduct of the experiment, the categories of prediction included, and outlines the evaluation and assessment procedures. The 10 CASP experiments span almost 20 years of progress in the field of protein structure modeling, and there have been enormous advances in methods and model accuracy in that period. Notable in this round is the first sustained improvement of models with refinement methods, using molecular dynamics. For the first time, we tested the ability of modeling methods to make use of sparse experimental three-dimensional contact information, such as may be obtained from new experimental techniques, with encouraging results. On the other hand, new contact prediction methods, though holding considerable promise, have yet to make an impact in CASP testing. The nature of CASP targets has been changing in recent CASPs, reflecting shifts in experimental structural biology, with more irregular structures, more multi-domain and multi-subunit structures, and less standard versions of known folds. When allowance is made for these factors, we continue to see steady progress in the overall accuracy of models, particularly resulting from improvement of non-template regions.

  12. Standard test method for electrochemical critical pitting temperature testing of stainless steels

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1999-01-01

    1.1 This test method covers a procedure for the evaluation of the resistance of stainless steel and related alloys to pitting corrosion based on the concept of the determination of a potential independent critical pitting temperature (CPT). 1.2 This test methods applies to wrought and cast products including but not restricted to plate, sheet, tubing, bar, forgings, and welds, (see Note 1). Note 1—Examples of CPT measurements on sheet, plate, tubing, and welded specimens for various stainless steels can be found in Ref (1). See the research reports (Section 14). 1.3 The standard parameters recommended in this test method are suitable for characterizing the CPT of austenitic stainless steels and other related alloys with a corrosion resistance ranging from that corresponding to solution annealed UNS S31600 (Type 316 stainless steel) to solution annealed UNS S31254 (6 % Mo stainless steel). 1.4 This test method may be extended to stainless steels and other alloys related to stainless steel that have a CPT...

  13. Critical assessment of methods of protein structure prediction (CASP) - round x

    KAUST Repository

    Moult, John

    2013-12-17

    This article is an introduction to the special issue of the journal PROTEINS, dedicated to the tenth Critical Assessment of Structure Prediction (CASP) experiment to assess the state of the art in protein structure modeling. The article describes the conduct of the experiment, the categories of prediction included, and outlines the evaluation and assessment procedures. The 10 CASP experiments span almost 20 years of progress in the field of protein structure modeling, and there have been enormous advances in methods and model accuracy in that period. Notable in this round is the first sustained improvement of models with refinement methods, using molecular dynamics. For the first time, we tested the ability of modeling methods to make use of sparse experimental three-dimensional contact information, such as may be obtained from new experimental techniques, with encouraging results. On the other hand, new contact prediction methods, though holding considerable promise, have yet to make an impact in CASP testing. The nature of CASP targets has been changing in recent CASPs, reflecting shifts in experimental structural biology, with more irregular structures, more multi-domain and multi-subunit structures, and less standard versions of known folds. When allowance is made for these factors, we continue to see steady progress in the overall accuracy of models, particularly resulting from improvement of non-template regions.

  14. Study on critical effect in lattice homogenization via Monte Carlo method

    International Nuclear Information System (INIS)

    Li Mancang; Wang Kan; Yao Dong

    2012-01-01

    In contrast to the traditional deterministic lattice codes, generating the homogenization multigroup constants via Monte Carlo method overcomes the difficulties in geometry and treats energy in continuum. thus provides more accuracy parameters. An infinite lattice of identical symmetric motives is usually assumed when performing the homogenization. However, the finite size of a reactor is reality and it should influence the lattice calculation. In practice of the homogenization with Monte Carlo method, B N theory is applied to take the leakage effect into account. The fundamental mode with the buckling B is used as a measure of the finite size. The critical spectrum in the solution of 0-dimensional fine-group B 1 equations is used to correct the weighted spectrum for homogenization. A PWR prototype core is examined to verify that the presented method indeed generates few group constants effectively. In addition, a zero power physical experiment verification is performed. The results show that B N theory is adequate for leakage correction in the multigroup constants generation via Monte Carlo method. (authors)

  15. A fixed-jaw method to protect critical organs during intensity-modulated radiotherapy

    International Nuclear Information System (INIS)

    Chen, Jiayun; Chen, Xinyuan; Huang, Manni; Dai, Jianrong

    2014-01-01

    Intensity-modulated radiotherapy (IMRT) plays an important role in cancer radiotherapy. For some patients being treated with IMRT, the extremely low tolerances of critical organs (such as lens, ovaries, and testicles) cannot be met during treatment planning. The aim of this article is to introduce a new planning method to overcome that problem. In current planning practice, jaw positions are automatically set to cover all target volumes by the planning system (e.g., Pinnacle 3 system). Because of such settings, critical organs may be fully blocked by the multileaf collimator (MLC), but they still sit in the field that is shaped by collimator jaws. These critical organs receive doses from the transmission and leakage of MLC leaves. We manually fixed jaw positions to block them to further reduce such doses. This method has been used for different treatment sites in our clinic, and it was thoroughly evaluated in patients with radical hysterectomy plus ovarian transposition after surgery. For each patient, 2 treatment plans were designed with the same optimization parameters: the original plan with automatically chosen jaw positions (called O-plan) and the plan with fixed-jaw positions (named F-plan). In the F-plan, the jaws were manually fixed to block the ovaries. For target coverage, the mean conformity index (CI) of the F-plan (1.28 ± 0.02) was remarkably lower than that of the O-plan (1.53 ± 0.09) (p < 0.05). The F-plan and the O-plan performed similarly in target dose homogeneity. Meanwhile, for the critical organ sparing, the mean dose of both ovaries were much lower in the F-plan than that in the O-plan (p < 0.05). The V 20 , V 30 , and V 40 of bladder were also lower in the F-plan (93.57 ± 1.98, 73.99 ± 5.76, and 42.33 ± 3.7, respectively) than those in the O-plan (97.98 ± 1.11, 85.07 ± 4.04, and 49.71 ± 3.63, respectively) (p < 0.05). The maximum dose to the spinal cord planning organ at risk (OAR) volume (PRV) in the O-plan (3940.24 ± 102.8) was

  16. Expert meeting on critical limits for heavy metals and methods for their application. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Schuetze, G [comp.

    2003-07-01

    The Berlin meeting was structured according to its most important tasks (according to the recommendations of Sorrento 2002): - Review of the harmonised set of Critical Limits for heavy metals for soils and waters, whereby inclusion of limits for Hg and of human health effects was most important; - Further development of transfer functions of Pb, Cd and Hg for soils and sediments, with emphasis on their applicability to the broad spectrum of European soils;- General methodological aspects, including the - choice of approaches (critical loads model versus stand-still model) according to the 'decision tree', proposed in Sorrento (2002), - identification and European-wide mapping of present heavy metals pollution (Pb, Cd, Hg) of soils and their sources, - methods to consider other heavy metal inputs to soils and surface waters than atmospheric pollution, - peculiarities and applicability of an effect-based approach for Hg. These headings were at the same time the themes of three draft background documents provided before the expert meeting and the names and the scope of three working groups during the workshop. For each of the items a list of most relevant questions was prepared. The proceedings of the expert meeting in Berlin, provided for the benefit of a wider number of interested scientists, advisors and decision makers, contain a short reflection on future work to be done, the workshop report (Minutes), including the conclusions and recommendations of the three working groups and six annexes, as well as the abstracts of short presentations and posters presented at the meeting. (orig.)

  17. Identifying Critical Factors in the Eco-Efficiency of Remanufacturing Based on the Fuzzy DEMATEL Method

    Directory of Open Access Journals (Sweden)

    Qianwang Deng

    2015-11-01

    Full Text Available Remanufacturing can bring considerable economic and environmental benefits such as cost saving, conservation of energy and resources, and reduction of emissions. With the increasing awareness of sustainable manufacturing, remanufacturing gradually becomes the research priority. Most studies concentrate on the analysis of influencing factors, or the evaluation of the economic and environmental performance in remanufacturing, while little effort has been devoted to investigating the critical factors influencing the eco-efficiency of remanufacturing. Considering the current development of the remanufacturing industry in China, this paper proposes a set of factors influencing the eco-efficiency of remanufacturing and then utilizes a fuzzy Decision Making Trial and Evaluation Laboratory (DEMATEL method to establish relation matrixes reflecting the interdependent relationships among these factors. Finally, the contributions of each factor to eco-efficiency and mutual influence values among them are obtained, and critical factors in eco-efficiency of remanufacturing are identified. The results of the present work can provide theoretical supports for the government to make appropriate policies to improve the eco-efficiency of remanufacturing.

  18. Critical thinking: concept analysis from the perspective of Rodger's evolutionary method of concept analysis

    Directory of Open Access Journals (Sweden)

    Fábio da Costa Carbogim

    Full Text Available ABSTRACT Objective: to analyze the concept of critical thinking (CT in Rodger's evolutionary perspective. Method: documentary research undertaken in the Cinahl, Lilacs, Bdenf and Dedalus databases, using the keywords of 'critical thinking' and 'Nursing', without limitation based on year of publication. The data were analyzed in accordance with the stages of Rodger's conceptual model. The following were included: books and articles in full, published in Portuguese, English or Spanish, which addressed CT in the teaching and practice of Nursing; articles which did not address aspects related to the concept of CT were excluded. Results: the sample was made up of 42 works. As a substitute term, emphasis is placed on 'analytical thinking', and, as a related factor, decision-making. In order, the most frequent preceding and consequent attributes were: ability to analyze, training of the student nurse, and clinical decision-making. As the implications of CT, emphasis is placed on achieving effective results in care for the patient, family and community. Conclusion: CT is a cognitive skill which involves analysis, logical reasoning and clinical judgment, geared towards the resolution of problems, and standing out in the training and practice of the nurse with a view to accurate clinical decision-making and the achieving of effective results.

  19. Study of time-critical diagnostic method for emergency operation of nuclear power plant

    International Nuclear Information System (INIS)

    Gofuku, A.; Yoshikawa, H.; Itoh, K.; Wakabayashi, J.

    1986-01-01

    In order to support the emergency operation of nuclear power plant, the method of time-critical diagnostic plant analyzer has been investigated. The conception of the emergency operation support center is proposed and two types of plant analyzer may be installed in this center. One analyzer is a real-time tracking simulation code using the observed signals and another is a fast trend-prediction code. A real-time tracking code, TOKRAC, has been developed for analyzing the PWR primary loop thermo-hydraulics at SBLOCA, and the applicability of this code was examined by the numerical experiments for the initial phase transient of both TMI-2 accident and 6% coldleg SBLOCA of a Westinghouse-type PWR plant. The results showed that fairly good tracking was carried out by TOKRAC. The CPU time of TOKRAC was about 12-14 percent of real-time

  20. Methods of cell purification: a critical juncture for laboratory research and translational science.

    Science.gov (United States)

    Amos, Peter J; Cagavi Bozkulak, Esra; Qyang, Yibing

    2012-01-01

    Research in cell biology and the development of translational technologies are driven by competition, public expectations, and regulatory oversight, putting these fields at a critical juncture. Success in these fields is quickly becoming dependent on the ability of researchers to identify and isolate specific cell populations from heterogeneous mixtures accurately and efficiently. Many methods for cell purification have been developed, and each has advantages and disadvantages that must be considered in light of the intended application. Current cell separation strategies make use of surface proteins, genetic expression, and physics to isolate specific cells by phenotypic traits. Cell purification is also dependent on the cellular reagents available for use and the intended application, as these factors may preclude certain mechanisms used in the processes of labeling and sorting cells. Copyright © 2011 S. Karger AG, Basel.

  1. The use of arithmetic average method in identifying critical success criteria for Homestay Programmes

    Science.gov (United States)

    Daud, Shahidah Md; Ramli, Razamin; Kasim, Maznah Mat; Kayat, Kalsom; Razak, Rafidah Abd

    2015-12-01

    Malaysian Homestay is very unique. It is classified as Community Based Tourism (CBT). Homestay Programme which is a community events where a tourist stays together with a host family for a period of time and enjoying cultural exchange besides having new experiences. Homestay programme has booming the tourism industry since there is over 100 Homestay Programme currently being registered with the Ministry of Culture and Tourism Malaysia. However, only few Homestay Programme enjoying the benefits of success Homestay Programme. Hence, this article seeks to identify the critical success factors for a Homestay Programme in Malaysia. An Arithmetic Average method is utilized to further evaluate the identified success factors in a more meaningful way. The findings will help Homestay Programme function as a community development tool that manages tourism resources. Thus, help the community in improving local economy and creating job opportunities.

  2. Critical assessment of methods of protein structure prediction (CASP)-round IX

    KAUST Repository

    Moult, John; Fidelis, Krzysztof; Kryshtafovych, Andriy; Tramontano, Anna

    2011-01-01

    This article is an introduction to the special issue of the journal PROTEINS, dedicated to the ninth Critical Assessment of Structure Prediction (CASP) experiment to assess the state of the art in protein structure modeling. The article describes the conduct of the experiment, the categories of prediction included, and outlines the evaluation and assessment procedures. Methods for modeling protein structure continue to advance, although at a more modest pace than in the early CASP experiments. CASP developments of note are indications of improvement in model accuracy for some classes of target, an improved ability to choose the most accurate of a set of generated models, and evidence of improvement in accuracy for short "new fold" models. In addition, a new analysis of regions of models not derivable from the most obvious template structure has revealed better performance than expected.

  3. After critical care: patient support after critical care. A mixed method longitudinal study using email interviews and questionnaires.

    Science.gov (United States)

    Pattison, Natalie; O'Gara, Geraldine; Rattray, Janice

    2015-08-01

    To explore experiences and needs over time, of patients discharged from ICU using the Intensive Care Experience (ICE-q) questionnaire, Hospital Anxiety and Depression Scale (HADS) and EuroQoL (EQ-5D), associated clinical predictors (APACHE II, TISS, Length of stay, RIKER scores) and in-depth email interviewing. A mixed-method, longitudinal study of patients with >48hour ICU stays at 2 weeks, 6 months, 12 months using the ICE-q, HADS, EQ-5D triangulated with clinical predictors, including age, gender, length of stay (ICU and hospital), APACHE II and TISS. In-depth qualitative email interviews were completed at 1 month and 6 months. Grounded Theory analysis was applied to interview data and data were triangulated with questionnaire and clinical data. Data was collected from January 2010 to March 2012 from 77 participants. Both mean EQ-5D visual analogue scale, utility scores and HADS scores improved from 2 weeks to 6 months, (p=Email interviews offer a convenient method of gaining in-depth interview data and could be used as part of ICU follow-up. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  4. Risk Management method to ERP systems implementation based os critical sucess factors

    Directory of Open Access Journals (Sweden)

    Márcio Saez Caputo

    2004-10-01

    Full Text Available From the second half of years 90, the Enterprise Resource Planning (ERP systems implementation appears like one of the main investment focus related to the use of information technology in the companies, which aimed to acquire competitive advantages through cost reduction and differentiation of products with the use of these systems. ERP implementation showed to be much more than a technology project, involving structural and managing changes, becoming a complex and high risk process for the organizations. In the literature specialized on ERP, there are many examples of the difficulties of this type of project and about implementations that had not reached the expected objectives, frustrating the expectations of the contractors. The present work describes, first of all, the development of a risk management method to ERP systems implementation, based on critical success factors. Then, a case of application of the considered method is analyzed, detailing the steps and the results gotten until the moment. To the end, evidences regarding to how the method helps to improve risk management during ERP implementations are presented.

  5. Formal methods and their applicability in the development of safety critical software systems

    International Nuclear Information System (INIS)

    Sievertsen, T.

    1995-01-01

    The OECD Halden Reactor Project has for a number of years been involved in the development and application of a formal software specification and development method based on algebraic specification and the HRP Prover. In parallel to this activity the Project has been evaluating and comparing different methods and approaches to formal software development by their application on realistic case examples. Recent work has demonstrated that algebraic specification and the HRP Prover can be used both in the specification and design of a software system, even down to a concrete model which can be translated into the chosen implementation language. The HRP Prover is currently being used in a case study on the applicability of the methodology in the development of a power range monitoring system for a nuclear power plant. The presentation reviews some of the experiences drawn from the Project's research activities in this area, with special emphasis on questions relating to applicability and limitations, and the role of formal methods in the development of safety-critical software systems. (14 refs., 1 fig.)

  6. Fast critical assembly safeguards: NDA methods for highly enriched uranium. Summary report, October 1978-September 1979

    International Nuclear Information System (INIS)

    Bellinger, F.O.; Winslow, G.H.

    1980-12-01

    Nondestructive assay (NDA) methods, principally passive gamma measurements and active neutron interrogation, have been studied for their safeguards effectiveness and programmatic impact as tools for making inventories of highly enriched uranium fast critical assembly fuel plates. It was concluded that no NDA method is the sole answer to the safeguards problem, that each of those emphasized here has its place in an integrated safeguards system, and that each has minimum facility impact. It was found that the 185-keV area, as determined with a NaI detector, was independent of highly-enriched uranium (HEU) plate irradiation history, though the random neutron driver methods used here did not permit accurate assay of irradiated plates. Containment procedures most effective for accurate assaying were considered, and a particular geometry is recommended for active interrogation by a random driver. A model, pertinent to that geometry, which relates the effects of multiplication and self-absorption, is described. Probabilities of failing to detect that plates are missing are examined

  7. Abstract Knowledge in the Broken-String Problem: Evidence from Nonhuman Primates and Pre-Schoolers

    Science.gov (United States)

    Mayer, Carolina; Call, Josep; Albiach-Serrano, Anna; Visalberghi, Elisabetta; Sabbatini, Gloria; Seed, Amanda

    2014-01-01

    There is still large controversy about whether abstract knowledge of physical problems is uniquely human. We presented 9 capuchin monkeys, 6 bonobos, 6 chimpanzees and 48 children with two versions of a broken-string problem. In the standard condition, participants had to choose between an intact and a broken string as means to a reward. In the critical condition, the functional parts of the strings were covered up and replaced by perceptually similar, but non-functional cues. Apes, monkeys and young children performed significantly better in the standard condition in which the cues played a functional role, indicating knowledge of the functional properties involved. Moreover, a control experiment with chimpanzees and young children ruled out that this difference in performance could be accounted for by differences of perceptual feedback in the two conditions. We suggest that, similar to humans, nonhuman primates partly rely on abstract concepts in physical problem-solving. PMID:25272161

  8. New design procedure development of future reactor critical power estimation. (1) Practical design-by-analysis method for BWR critical power design correlation

    International Nuclear Information System (INIS)

    Yamamoto, Yasushi; Mitsutake, Toru

    2007-01-01

    For present BWR fuels, the full mock-up thermal-hydraulic test, such as the critical power measurement test, pressure drop measurement test and so on, has been needed. However, the full mock-up test required the high costs and large-scale test facility. At present, there are only a few test facilities to perform the full mock-up thermal-hydraulic test in the world. Moreover, for future BWR, the bundle size tends to be larger, because of reducing the plant construction costs and minimizing the routine check period. For instance, AB1600, improved ABWR, was proposed from Toshiba, whose bundle size was 1.2 times larger than the conventional BWR fuel size. It is too expensive and far from realistic to perform the full mock-up thermal-hydraulic test for such a large size fuel bundle. The new design procedure is required to realize the large scale bundle design development, especially for the future reactor. Therefore, the new design procedure, Practical Design-by-Analysis (PDBA) method, has been developed. This new procedure consists of the partial mock-up test and numerical analysis. At present, the subchannel analysis method based on three-fluid two-phase flow model only is a realistic choice. Firstly, the partial mock-up test is performed, for instance, the 1/4 partial mock-up bundle. Then, the first-step critical power correlation coefficients are evaluated with the measured data. The input data, such as the spacer effect model coefficient, on the subchannel analysis are also estimated with the data. Next, the radial power effect on the critical power of the full-bundle size was estimated with the subchannel analysis. Finally, the critical power correlation is modified by the subchannel analysis results. In the present study, the critical power correlation of the conventional 8x8 BWR fuel was developed with the PDBA method by 4x4 partial mock-up tests and the subchannel analysis code. The accuracy of the estimated critical power was 3.8%. The several themes remain to

  9. A journey from nuclear criticality methods to high energy density radflow experiments

    Energy Technology Data Exchange (ETDEWEB)

    Urbatsch, Todd James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-05-30

    Los Alamos National Laboratory is a nuclear weapons laboratory supporting our nation's defense. In support of this mission is a high energy-density physics program in which we design and execute experiments to study radiationhydrodynamics phenomena and improve the predictive capability of our largescale multi-physics software codes on our big-iron computers. The Radflow project’s main experimental effort now is to understand why we haven't been able to predict opacities on Sandia National Laboratory's Z-machine. We are modeling an increasing fraction of the Z-machine's dynamic hohlraum to find multi-physics explanations for the experimental results. Further, we are building an entirely different opacity platform on Lawrence Livermore National Laboratory's National Ignition Facility (NIF), which is set to get results early 2017. Will the results match our predictions, match the Z-machine, or give us something entirely different? The new platform brings new challenges such as designing hohlraums and spectrometers. The speaker will recount his history, starting with one-dimensional Monte Carlo nuclear criticality methods in graduate school, radiative transfer methods research and software development for his first 16 years at LANL, and, now, radflow technology and experiments. Who knew that the real world was more than just radiation transport? Experiments aren't easy, but they sure are fun.

  10. A journey from nuclear criticality methods to high energy density radflow experiments

    Energy Technology Data Exchange (ETDEWEB)

    Urbatsch, Todd James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-11-08

    Los Alamos National Laboratory is a nuclear weapons laboratory supporting our nation's defense. In support of this mission is a high energy-density physics program in which we design and execute experiments to study radiationhydrodynamics phenomena and improve the predictive capability of our largescale multi-physics software codes on our big-iron computers. The Radflow project’s main experimental effort now is to understand why we haven't been able to predict opacities on Sandia National Laboratory's Z-machine. We are modeling an increasing fraction of the Z-machine's dynamic hohlraum to find multi-physics explanations for the experimental results. Further, we are building an entirely different opacity platform on Lawrence Livermore National Laboratory's National Ignition Facility (NIF), which is set to get results early 2017. Will the results match our predictions, match the Z-machine, or give us something entirely different? The new platform brings new challenges such as designing hohlraums and spectrometers. The speaker will recount his history, starting with one-dimensional Monte Carlo nuclear criticality methods in graduate school, radiative transfer methods research and software development for his first 16 years at LANL, and, now, radflow technology and experiments. Who knew that the real world was more than just radiation transport? Experiments aren't easy and they are as saturated with politics as a presidential election, but they sure are fun.

  11. Expert meeting on critical limits for heavy metals and methods for their application. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Schuetze, G. (comp.)

    2003-07-01

    The Berlin meeting was structured according to its most important tasks (according to the recommendations of Sorrento 2002): - Review of the harmonised set of Critical Limits for heavy metals for soils and waters, whereby inclusion of limits for Hg and of human health effects was most important; - Further development of transfer functions of Pb, Cd and Hg for soils and sediments, with emphasis on their applicability to the broad spectrum of European soils;- General methodological aspects, including the - choice of approaches (critical loads model versus stand-still model) according to the 'decision tree', proposed in Sorrento (2002), - identification and European-wide mapping of present heavy metals pollution (Pb, Cd, Hg) of soils and their sources, - methods to consider other heavy metal inputs to soils and surface waters than atmospheric pollution, - peculiarities and applicability of an effect-based approach for Hg. These headings were at the same time the themes of three draft background documents provided before the expert meeting and the names and the scope of three working groups during the workshop. For each of the items a list of most relevant questions was prepared. The proceedings of the expert meeting in Berlin, provided for the benefit of a wider number of interested scientists, advisors and decision makers, contain a short reflection on future work to be done, the workshop report (Minutes), including the conclusions and recommendations of the three working groups and six annexes, as well as the abstracts of short presentations and posters presented at the meeting. (orig.)

  12. Literature research concerning alternative methods for validation of criticality calculation systems

    International Nuclear Information System (INIS)

    Behler, Matthias

    2016-05-01

    Beside radiochemical analysis of irradiated fuel and critical experiments, which has become a well-established basis for the validation of depletion code and criticality codes respectively, also results of oscillation experiments or the operating conditions of power reactor and research reactors can provide useful information for the validation of the above mentioned codes. Based on a literature review the potential of the utilization of oscillation experiment measurements for the validation of criticality codes is estimated. It is found that the reactivity measurements for actinides and fission products within the CERES program on the reactors DIMPLE (Winfrith, UK) and MINERVE (Cadarache, France) can give a valuable addition to the commonly used critical experiments for criticality code validation. However, there are approaches but yet no generally satisfactory solution for integrating the reactivity measurements in a quantitative bias determination for the neutron multiplication factor of typical application cases including irradiated spent fuel outside reactor cores, calculated using common criticality codes.

  13. α-Cut method based importance measure for criticality analysis in fuzzy probability – Based fault tree analysis

    International Nuclear Information System (INIS)

    Purba, Julwan Hendry; Sony Tjahyani, D.T.; Widodo, Surip; Tjahjono, Hendro

    2017-01-01

    Highlights: •FPFTA deals with epistemic uncertainty using fuzzy probability. •Criticality analysis is important for reliability improvement. •An α-cut method based importance measure is proposed for criticality analysis in FPFTA. •The α-cut method based importance measure utilises α-cut multiplication, α-cut subtraction, and area defuzzification technique. •Benchmarking confirm that the proposed method is feasible for criticality analysis in FPFTA. -- Abstract: Fuzzy probability – based fault tree analysis (FPFTA) has been recently developed and proposed to deal with the limitations of conventional fault tree analysis. In FPFTA, reliabilities of basic events, intermediate events and top event are characterized by fuzzy probabilities. Furthermore, the quantification of the FPFTA is based on fuzzy multiplication rule and fuzzy complementation rule to propagate uncertainties from basic event to the top event. Since the objective of the fault tree analysis is to improve the reliability of the system being evaluated, it is necessary to find the weakest path in the system. For this purpose, criticality analysis can be implemented. Various importance measures, which are based on conventional probabilities, have been developed and proposed for criticality analysis in fault tree analysis. However, not one of those importance measures can be applied for criticality analysis in FPFTA, which is based on fuzzy probability. To be fully applied in nuclear power plant probabilistic safety assessment, FPFTA needs to have its corresponding importance measure. The objective of this study is to develop an α-cut method based importance measure to evaluate and rank the importance of basic events for criticality analysis in FPFTA. To demonstrate the applicability of the proposed measure, a case study is performed and its results are then benchmarked to the results generated by the four well known importance measures in conventional fault tree analysis. The results

  14. CriticalEd

    DEFF Research Database (Denmark)

    Kjellberg, Caspar Mølholt; Meredith, David

    2014-01-01

    . Since the comments are not input sequentially, with regard to position, but in arbitrary order, this list must be sorted by copy/pasting the rows into place—an error-prone and time-consuming process. Scholars who produce critical editions typically use off-the-shelf music notation software......The best text method is commonly applied among music scholars engaged in producing critical editions. In this method, a comment list is compiled, consisting of variant readings and editorial emendations. This list is maintained by inserting the comments into a document as the changes are made......, consisting of a Sibelius plug-in, a cross-platform application, called CriticalEd, and a REST-based solution, which handles data storage/retrieval. A prototype has been tested at the Danish Centre for Music Publication, and the results suggest that the system could greatly improve the efficiency...

  15. The critical slab problem for pure-triplet anisotropic scattering by singular eigenfunction method

    Energy Technology Data Exchange (ETDEWEB)

    Tuereci, R.G. [Kirikkale Univ. (Turkey). Kirikkale Vocational School; Tuereci, D. [Ministery of Education, Ankara (Turkey). General Directorate of Secondary Education

    2017-12-15

    The infinite medium Green function can be written by using the jump condition, found Case's eigenfunctions. Thus, any reactor theory problem which is inplane geometry such the criticality problem as can be investigated by using the proper boundary conditions and suggested flux definitions. By using the criticality equation the critical thicknesses can be calculated as numerically. The selected numerical results can be tabulated.

  16. Finite test sets development method for test execution of safety critical software

    International Nuclear Information System (INIS)

    El-Bordany Ayman; Yun, Won Young

    2014-01-01

    It reads inputs, computes new states, and updates output for each scan cycle. Korea Nuclear Instrumentation and Control System (KNICS) has recently developed a fully digitalized Reactor Protection System (RPS) based on PLD. As a digital system, this RPS is equipped with a dedicated software. The Reliability of this software is crucial to NPPs safety where its malfunction may cause irreversible consequences and affect the whole system as a Common Cause Failure (CCF). To guarantee the reliability of the whole system, the reliability of this software needs to be quantified. There are three representative methods for software reliability quantification, namely the Verification and Validation (V and V) quality-based method, the Software Reliability Growth Model (SRGM), and the test-based method. An important concept of the guidance is that the test sets represent 'trajectories' (a series of successive values for the input variables of a program that occur during the operation of the software over time) in the space of inputs to the software.. Actually, the inputs to the software depends on the state of plant at that time, and these inputs form a new internal state of the software by changing values of some variables. In other words, internal state of the software at specific timing depends on the history of past inputs. Here the internal state of the software which can be changed by past inputs is named as Context of Software (CoS). In a certain CoS, a software failure occurs when a fault is triggered by some inputs. To cover the failure occurrence mechanism of a software, preceding researches insist that the inputs should be a trajectory form. However, in this approach, there are two critical problems. One is the length of the trajectory input. Input trajectory should long enough to cover failure mechanism, but the enough length is not clear. What is worse, to cover some accident scenario, one set of input should represent dozen hours of successive values

  17. Method for calculating the critical heat flux in mixed rod assemblies based on the tables of crisis in bundles

    International Nuclear Information System (INIS)

    Bobkov, V.P.

    2000-01-01

    The method for calculating the critical heat flux in the mixed rod assemblies, for example RBMK, containing three-four angle and peripheral macrocells, is presented. The method is based on generalization of experimental data in form of tables for the rods beams. It is recommended for the areas of parameters both provided for by experimental data and for others, where the data are absent. The advantages of the table method as follows: it is acceptable within a wide range of parameters and provides for smooth description of dependence of critical heat fluxes on these parameters; it is characterized by clearness, high reliability and accuracy and is easy in application [ru

  18. The impact of increased weekend physiotherapy service provision in critical care: a mixed methods study.

    Science.gov (United States)

    Duncan, Catharine; Hudson, Megan; Heck, Carol

    2015-01-01

    At the hospital studied, weekend physiotherapy (WEPT) is routinely provided and in 2013 WEPT was increased from one (PRE) to three (POST) physiotherapists (PTs) to cover intensive care and ward patients. (1) To evaluate the impact of increased WEPT on patient volumes, treatments provided and conditions treated in critical care and wards; and (2) to understand the PTs' perspectives on the new coverage model. A mixed methods design was utilized. The quantitative component consisted of retrospective document reviews of all weekend patients treated January 1-May 5 (PRE) and May 11-December 31 (POST). The qualitative component used a questionnaire to collect staff feedback. PRE-POST comparisons were conducted using χ(2) or Mann-Whitney U tests. Significant (p = 0.00) increases POST were seen in number of patients treated, number of mobility treatments provided and number of post-surgical patients seen in both clinical areas. The majority of survey respondents reported feeling adequately trained, but had concerns regarding the impact of increased WEPT on work-life balance. PTs perceived enhanced service was beneficial for continuity of weekday care and improved patient function. Future studies need to focus on measuring the effect of increased weekend provision on outcomes, preventing complications and length of stay.

  19. Structural identifiability of systems biology models: a critical comparison of methods.

    Directory of Open Access Journals (Sweden)

    Oana-Teodora Chis

    Full Text Available Analysing the properties of a biological system through in silico experimentation requires a satisfactory mathematical representation of the system including accurate values of the model parameters. Fortunately, modern experimental techniques allow obtaining time-series data of appropriate quality which may then be used to estimate unknown parameters. However, in many cases, a subset of those parameters may not be uniquely estimated, independently of the experimental data available or the numerical techniques used for estimation. This lack of identifiability is related to the structure of the model, i.e. the system dynamics plus the observation function. Despite the interest in knowing a priori whether there is any chance of uniquely estimating all model unknown parameters, the structural identifiability analysis for general non-linear dynamic models is still an open question. There is no method amenable to every model, thus at some point we have to face the selection of one of the possibilities. This work presents a critical comparison of the currently available techniques. To this end, we perform the structural identifiability analysis of a collection of biological models. The results reveal that the generating series approach, in combination with identifiability tableaus, offers the most advantageous compromise among range of applicability, computational complexity and information provided.

  20. Manual muscle testing: a method of measuring extremity muscle strength applied to critically ill patients.

    Science.gov (United States)

    Ciesla, Nancy; Dinglas, Victor; Fan, Eddy; Kho, Michelle; Kuramoto, Jill; Needham, Dale

    2011-04-12

    Survivors of acute respiratory distress syndrome (ARDS) and other causes of critical illness often have generalized weakness, reduced exercise tolerance, and persistent nerve and muscle impairments after hospital discharge. Using an explicit protocol with a structured approach to training and quality assurance of research staff, manual muscle testing (MMT) is a highly reliable method for assessing strength, using a standardized clinical examination, for patients following ARDS, and can be completed with mechanically ventilated patients who can tolerate sitting upright in bed and are able to follow two-step commands. (7, 8) This video demonstrates a protocol for MMT, which has been taught to ≥ 43 research staff who have performed >800 assessments on >280 ARDS survivors. Modifications for the bedridden patient are included. Each muscle is tested with specific techniques for positioning, stabilization, resistance, and palpation for each score of the 6-point ordinal Medical Research Council scale. Three upper and three lower extremity muscles are graded in this protocol: shoulder abduction, elbow flexion, wrist extension, hip flexion, knee extension, and ankle dorsiflexion. These muscles were chosen based on the standard approach for evaluating patients for ICU-acquired weakness used in prior publications. (1,2).

  1. Unsteady supercritical/critical dual flowpath inlet flow and its control methods

    Directory of Open Access Journals (Sweden)

    Jun LIU

    2017-12-01

    Full Text Available The characteristics of unsteady flow in a dual-flowpath inlet, which was designed for a Turbine Based Combined Cycle (TBCC propulsion system, and the control methods of unsteady flow were investigated experimentally and numerically. It was characterized by large-amplitude pressure oscillations and traveling shock waves. As the inlet operated in supercritical condition, namely the terminal shock located in the throat, the shock oscillated, and the period of oscillation was about 50 ms, while the amplitude was 6 mm. The shock oscillation was caused by separation in the diffuser. This shock oscillation can be controlled by extending the length of diffuser which reduces pressure gradient along the flowpath. As the inlet operated in critical condition, namely the terminal shock located at the shoulder of the third compression ramp, the shock oscillated, and the period of oscillation was about 7.5 ms, while the amplitude was 12 mm. At this condition, the shock oscillation was caused by an incompatible backpressure in the bleed region. It can be controlled by increasing the backpressure of the bleed region. Keywords: Airbreathing hypersonic vehicle, Dual flowpath inlet, Terminal shock oscillation, Turbine based combined cycle, Unsteady flow

  2. Drug Use Normalization: A Systematic and Critical Mixed-Methods Review.

    Science.gov (United States)

    Sznitman, Sharon R; Taubman, Danielle S

    2016-09-01

    Drug use normalization, which is a process whereby drug use becomes less stigmatized and more accepted as normative behavior, provides a conceptual framework for understanding contemporary drug issues and changes in drug use trends. Through a mixed-methods systematic review of the normalization literature, this article seeks to (a) critically examine how the normalization framework has been applied in empirical research and (b) make recommendations for future research in this area. Twenty quantitative, 26 qualitative, and 4 mixed-methods studies were identified through five electronic databases and reference lists of published studies. Studies were assessed for relevance, study characteristics, quality, and aspects of normalization examined. None of the studies applied the most rigorous research design (experiments) or examined all of the originally proposed normalization dimensions. The most commonly assessed dimension of drug use normalization was "experimentation." In addition to the original dimensions, the review identified the following new normalization dimensions in the literature: (a) breakdown of demographic boundaries and other risk factors in relation to drug use; (b) de-normalization; (c) drug use as a means to achieve normal goals; and (d) two broad forms of micro-politics associated with managing the stigma of illicit drug use: assimilative and transformational normalization. Further development in normalization theory and methodology promises to provide researchers with a novel framework for improving our understanding of drug use in contemporary society. Specifically, quasi-experimental designs that are currently being made feasible by swift changes in cannabis policy provide researchers with new and improved opportunities to examine normalization processes.

  3. Interpretation of Piezocones in Silt, Using Cavity Expansion and Critical State Methods

    DEFF Research Database (Denmark)

    Bakmar, Christian LeBlanc; Randolph, M. F.

    2008-01-01

    was simulated using cylindrical cavity expansion in conjunction with a plasticity model formulated within the framework of critical state soil mechanics. The results readily explain the low cone tip resistance measured in silt sediments; this is a derived effect of the silt having a large slope of the critical...... state line, resulting in rather weak and compressible behaviour at high mean effective stresses....

  4. A mutant screening method by critical annealing temperature-PCR for site-directed mutagenesis.

    Science.gov (United States)

    Liu, Ying; Wu, Ting; Song, Jian; Chen, Xuelian; Zhang, Yu; Wan, Yu

    2013-03-11

    Distinguishing desired mutants from parental templates and undesired mutants is a problem not well solved in Quikchange™ mutagenesis. Although Dpn I digestion can eliminate methylated parental (WT) DNA, the efficiency is not satisfying due to the existence of hemi-methylated DNA in the PCR products, which is resistant to Dpn I. The present study designed a novel critical annealing temperature (T(c))-PCR to replace Dpn I digestion for more perfect mutant distinguishing, in which part-overlapping primers containing mutation(s) were used to reduce initial concentration of template DNA in mutagenic PCR. A T(c)-PCR with the same mutagenic primers was performed without Dpn I digestion. The T(c) for each pair of the primers was identified by gradient PCR. The relationship between PCR-identified T(c) and T(m) of the primers was analyzed and modeled with correlation and regression. Gradient PCR identified a T(c) for each of 14 tested mutagenic primers, which could discriminate mismatched parental molecules and undesired mutants from desired mutants. The PCR-identified T(c) was correlated to the primer's T(m) (r = 0.804, P<0.0001). Thus, in practical applications, the T(c) can be easily calculated with a regression equation, T(c)= 48.81 + 0.253*T(m). The new protocol introduced a novel T(c)-PCR method for mutant screening which can more efficiently and accurately select against parental molecules and undesired mutations in mutagenic sequence segments.

  5. Can home garden produce have an impact on the nutritional status of pre-schoolers?

    Directory of Open Access Journals (Sweden)

    BM Selepe

    2011-01-01

    Full Text Available Aim of the study: This study set out to determine the impact of home gardens on the nutritional status of pre-school children in an informal settlement in South Africa. Methods: Children aged two to five years (n=40 were selected to participate in the study. The sampled children were divided into groups: 24-35 months (four boys and one girl, 36-47 months (four boys and five girls and 48-60 months (14 boys and 12 girls.The children’s anthropometric measurements were taken and recorded. Summary of Results: Twenty-five percent of boys (24-35 months were underweight and below the 50th percentile at the pre- and post-project stages. Of the boys aged 36-47 months, 25 per cent were stunted pre-project and had decreased to 50 per cent. Twenty-one percent of the older boys (48-60 months were within their normal height for age. Twenty-five percent of girls were underweight (36-47 months. All girls aged 24-35 months were below -2 standard deviations pre-project and were severely stunted postproject. The older girls were well nourished with means of height-for-age at -0.88 (below 50th percentile pre-project and -0.92 (below 50th percentile post-project. Conclusions: The results highlight that malnutrition is problematic among children all age groups in this sample. Home gardens had no statistically significant impact on anthropometric measurements of the children. A concerning, negative statistical difference was found between pre- and post-study height-for-age z-scores for boys, showing significant deterioration of nutritional status among boys.

  6. The Critical Success Factor Method: Establishing a Foundation for Enterprise Security Management

    National Research Council Canada - National Science Library

    Caralli, Richard A; Stevens, James F; Willke, Bradford J; Wilson, William R

    2004-01-01

    .... The organization must perform well in key areas on a consistent basis to achieve the mission. These key areas unique to the organization and the industry in which it competes can be defined as the organization's critical success factors...

  7. Study into critical properties of 3D frustrated Heisenberg model on triangular lattice by the use of Monte Carlo methods

    International Nuclear Information System (INIS)

    Murtazaev, A.K.; Ramazanov, M.K.; Badiev, M.K.

    2009-01-01

    The critical properties of the 3D frustrated antiferromagnetic Heisenberg model on a triangular lattice are investigated by the replica Monte Carlo method. The static magnetic and chiral critical exponents of heat capacity a = 0.05(2), magnetization Β 0.30(1), Β k = 0.52(2), susceptibility Γ = 1.36(2), Γ k = 0.93(3), and correlation radius Ν 0.64(1), Ν k = 0.64(2) are calculated by using the finitesize scaling theory. The critical Fisher exponents η = - 0.06(3), η k = 0.63(4) for this model are estimated for the first time. A new universality class of the critical behavior is shown to be formed by the 3D frustrated Heisenberg model on the triangular lattice. A type of the interlayer exchange interaction is found to influence the universality class of antiferromagnetic Heisenberg model on the a triangular lattice.

  8. The CREATE Method Does Not Result in Greater Gains in Critical Thinking than a More Traditional Method of Analyzing the Primary Literature †

    Science.gov (United States)

    Segura-Totten, Miriam; Dalman, Nancy E.

    2013-01-01

    Analysis of the primary literature in the undergraduate curriculum is associated with gains in student learning. In particular, the CREATE (Consider, Read, Elucidate hypotheses, Analyze and interpret the data, and Think of the next Experiment) method is associated with an increase in student critical thinking skills. We adapted the CREATE method within a required cell biology class and compared the learning gains of students using CREATE to those of students involved in less structured literature discussions. We found that while both sets of students had gains in critical thinking, students who used the CREATE method did not show significant improvement over students engaged in a more traditional method for dissecting the literature. Students also reported similar learning gains for both literature discussion methods. Our study suggests that, at least in our educational context, the CREATE method does not lead to higher learning gains than a less structured way of reading primary literature. PMID:24358379

  9. Comparison of COD, R6, and J-contour integral methods of defect assessment, modified to give critical flaw sizes

    International Nuclear Information System (INIS)

    Burdekin, F.M.; Turner, C.E.

    1982-01-01

    A comparative study of the application of different elastic-plastic fracture mechanics methods to the calculation of critical defect sizes in pressure vessels showed widely varying results. The present authors have investigated in detail the reasons for the variations resulting from the use of the CEGB R6, COD design curve, and J-design curve methods to the particular pressure vessel problems. To obtain reasonable agreement between the three methods for the calculation of critical flaw sizes in high stress gradient situations, the published COD method in PD6493 has to be modified to remove its inherent safety factor, and to allow for stress gradients, and a consistent treatment for gross yielding/collapse has to be adopted for all three methods. (author)

  10. Assessment of cognitive bias in decision-making and leadership styles among critical care nurses: a mixed methods study.

    Science.gov (United States)

    Lean Keng, Soon; AlQudah, Hani Nawaf Ibrahim

    2017-02-01

    To raise awareness of critical care nurses' cognitive bias in decision-making, its relationship with leadership styles and its impact on care delivery. The relationship between critical care nurses' decision-making and leadership styles in hospitals has been widely studied, but the influence of cognitive bias on decision-making and leadership styles in critical care environments remains poorly understood, particularly in Jordan. Two-phase mixed methods sequential explanatory design and grounded theory. critical care unit, Prince Hamza Hospital, Jordan. Participant sampling: convenience sampling Phase 1 (quantitative, n = 96), purposive sampling Phase 2 (qualitative, n = 20). Pilot tested quantitative survey of 96 critical care nurses in 2012. Qualitative in-depth interviews, informed by quantitative results, with 20 critical care nurses in 2013. Descriptive and simple linear regression quantitative data analyses. Thematic (constant comparative) qualitative data analysis. Quantitative - correlations found between rationality and cognitive bias, rationality and task-oriented leadership styles, cognitive bias and democratic communication styles and cognitive bias and task-oriented leadership styles. Qualitative - 'being competent', 'organizational structures', 'feeling self-confident' and 'being supported' in the work environment identified as key factors influencing critical care nurses' cognitive bias in decision-making and leadership styles. Two-way impact (strengthening and weakening) of cognitive bias in decision-making and leadership styles on critical care nurses' practice performance. There is a need to heighten critical care nurses' consciousness of cognitive bias in decision-making and leadership styles and its impact and to develop organization-level strategies to increase non-biased decision-making. © 2016 John Wiley & Sons Ltd.

  11. Determination of the Critical Stress Associated with Dynamic Phase Transformation in Steels by Means of Free Energy Method

    Directory of Open Access Journals (Sweden)

    Clodualdo Aranas

    2018-05-01

    Full Text Available The double differentiation method overestimates the critical stress associated with the initiation of dynamic transformation (DT because significant amounts of the dynamic phase must be present in order for its effect on the work hardening rate to be detectable. In this work, an alternative method (referred to here as the free energy method is presented based on the thermodynamic condition that the driving force is equal to the total energy obstacle during the exact moment of transformation. The driving force is defined as the difference between the DT critical stress (measured in the single-phase austenite region and the yield stress of the fresh ferrite that takes its place. On the other hand, the energy obstacle consists of the free energy difference between austenite and ferrite, and the work of shear accommodation and dilatation associated with the phase transformation. Here, the DT critical stresses in a C-Mn steel were calculated using the free energy method at temperatures ranging from 870 °C to 1070 °C. The results show that the calculated critical stress using the present approach appears to be more accurate than the values measured by the double differentiation method.

  12. An application of the 'end-point' method to the minimum critical mass problem in two group transport theory

    International Nuclear Information System (INIS)

    Williams, M.M.R.

    2003-01-01

    A two group integral equation derived using transport theory, which describes the fuel distribution necessary for a flat thermal flux and minimum critical mass, is solved by the classical end-point method. This method has a number of advantages and in particular highlights the changing behaviour of the fissile mass distribution function in the neighbourhood of the core-reflector interface. We also show how the reflector thermal flux behaves and explain the origin of the maximum which arises when the critical size is less than that corresponding to minimum critical mass. A comparison is made with diffusion theory and the necessary and somewhat artificial presence of surface delta functions in the fuel distribution is shown to be analogous to the edge transients that arise naturally in transport theory

  13. Critical review of methods for risk ranking of food related hazards, based on risks for human health

    DEFF Research Database (Denmark)

    van der Fels-Klerx, H. J.; van Asselt, E. D.; Raley, M.

    2018-01-01

    This study aimed to critically review methods for ranking risks related to food safety and dietary hazards on the basis of their anticipated human health impacts. A literature review was performed to identify and characterize methods for risk ranking from the fields of food, environmental science......, and the risk ranking method characterized. The methods were then clustered - based on their characteristics - into eleven method categories. These categories included: risk assessment, comparative risk assessment, risk ratio method, scoring method, cost of illness, health adjusted life years, multi......-criteria decision analysis, risk matrix, flow charts/decision trees, stated preference techniques and expert synthesis. Method categories were described by their characteristics, weaknesses and strengths, data resources, and fields of applications. It was concluded there is no single best method for risk ranking...

  14. Measuring critical thinking in pre-registration midwifery students: A multi-method approach.

    Science.gov (United States)

    Carter, Amanda G; Creedy, Debra K; Sidebotham, Mary

    2018-02-01

    Test the concurrent validity of three newly developed tools (student self-rating, preceptor rating, and reflective writing) that aim to measure critical thinking in midwifery practice. A descriptive matched cohort design was used. Australian research intensive university offering a three year Bachelor of Midwifery programme. Fifty-five undergraduate midwifery students. Students assessed their ability to apply critical thinking in midwifery practice using a 25-item tool and a 5-item subscale in Motivated Strategies for Learning Questionnaire. Clinical preceptors completed a 24-item tool assessing the students' application of critical thinking in practice. Reflective writing by students was assessed by midwifery academics using a 15-item tool. Internal reliability, and concurrent validity were assessed. Correlations, t-tests, multiple regression and confidence levels were calculated for the three scales and associations with student characteristics. The three scales achieved good internal reliability with a Cronbach's alpha coefficient between 0.93 and 0.97. Matched total scores for the three critical thinking scales were moderately correlated; student/preceptor (r=0.36, pstudent/reflective writing (r=0.38, pstudents with a previous degree, but only significant for reflective writing (t (53)=-2.35, p=0.023). Preceptor ratings were predictive of GPA (beta=0.50, pStudents' self-rating scores were predictive of year level (beta=0.32, pstudent, preceptor, and reflective writing tools were found to be reliable and valid measures of critical thinking. The three tools can be used individually or in combination to provide students with various sources of feedback to improve their practice. The tools allow formative measurement of critical thinking over time. Further testing of the tools with larger, diverse samples is recommended. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  15. A Comparison of Case Study and Traditional Teaching Methods for Improvement of Oral Communication and Critical-Thinking Skills

    Science.gov (United States)

    Noblitt, Lynnette; Vance, Diane E.; Smith, Michelle L. DePoy

    2010-01-01

    This study compares a traditional paper presentation approach and a case study method for the development and improvement of oral communication skills and critical-thinking skills in a class of junior forensic science majors. A rubric for rating performance in these skills was designed on the basis of the oral communication competencies developed…

  16. Formal Methods for Industrial Critical Systems : 17th International Workshop, FMICS 2012, Paris, France, August 27-28, 2012. Proceedings

    NARCIS (Netherlands)

    Stoelinga, Mariëlle; Pinger, Ralf

    This volume contains the papers presented at FMICS 2012, the 17th International Workshop on Formal Methods for Industrial Critical Systems, taking place August 27–28, 2012, in Paris, France. The aim of the FMICS workshop series is to provide a forum for researchers who are interested in the

  17. A Critical Review of Qualitative Research Methods in Evaluating Nursing Curriculum Models: Implication for Nursing Education in the Arab World

    Science.gov (United States)

    Devadas, Briliya

    2016-01-01

    Aim: The purpose of this critical literature review was to examine qualitative studies done on innovative nursing curriculums in order to determine which qualitative methods have been most effective in investigating the effectiveness of the curriculum and which would be most appropriate in an Arab Islamic country. Data Sources: At least 25 studies…

  18. Owning My Thoughts Was Difficult: Encouraging Students to Read and Write Critically in a Tertiary Qualitative Research Methods Course

    Science.gov (United States)

    Wiles, Janine L.; Allen, Ruth E. S.; Butler, Rachael

    2016-01-01

    This paper adds to the nascent literature on teaching research methods and what students learn from courses and assessment. Postgraduate students are often confronted with large amounts of reading, and the content of material can be intimidating. Convincing them also to engage critically with readings is even more difficult. We report on a…

  19. Consumer research in the early stages of new product development: A critical review of methods and techniques

    NARCIS (Netherlands)

    Kleef, van E.; Trijp, van J.C.M.; Luning, P.A.

    2005-01-01

    Incorporating the `voice of the consumer' in early stages of the new product development process has been identified as a critical success factor for new product development. Yet, this step is often ignored or poorly executed. This may be due to lack of familiarity on which methods are available,

  20. Middle Schoolers Go Global

    Science.gov (United States)

    Wise, Mark; McTighe, Jay

    2017-01-01

    From global hunger to the world's water crisis, middle school students at New Jersey's West Windsor-Plainsboro Regional School District spend the last few days of the school year problem solving about the planet's most dire issues. With the Global Challenge, the school district's administrators not only want to implement an interesting and dynamic…

  1. A note on Fujikawa's method of determining the critical dimension of the relativistic string

    International Nuclear Information System (INIS)

    Petcher, D.N.; Holten, J.W. van.

    1987-04-01

    Fujikawa's derivation of the critical dimension of the relativistic string in the path integral formulation is reconsidered. It is shown that the correct prescription for choosing the functional measure is obtained by requiring standard BRST-invariance without modifications and that Fujikawa's choice of measure is not unique. We find a one-parameter family of BRST-invariant measures even after fixing a gauge for local Weyl rescalings. Gauge independence of the resulting theory is demonstrated in the critical number of dimensions. 13 refs

  2. Application of the modified neutron source multiplication method for a measurement of sub-criticality in AGN-201K reactor

    International Nuclear Information System (INIS)

    Myung-Hyun Kim

    2010-01-01

    Measurement of sub-criticality is a challenging and required task in nuclear industry both for nuclear criticality safety and physics test in nuclear power plant. A relatively new method named as Modified Neutron Source Multiplication Method (MNSM) was proposed in Japan. This method is an improvement of traditional Neutron Source Multiplication (NSM) Method, in which three correction factors are applied additionally. In this study, MNSM was tested in calculation of rod worth using an educational reactor in Kyung Hee University, AGN-201K. For this study, a revised nuclear data library and a neutron transport code system TRANSX-PARTISN were used for the calculation of correction factors for various control rod positions and source locations. Experiments were designed and performed to enhance errors in NSM from the location effects of source and detectors. MNSM can correct these effects but current results showed not much correction effects. (author)

  3. Theoretical study on new bias factor methods to effectively use critical experiments for improvement of prediction accuracy of neutronic characteristics

    International Nuclear Information System (INIS)

    Kugo, Teruhiko; Mori, Takamasa; Takeda, Toshikazu

    2007-01-01

    Extended bias factor methods are proposed with two new concepts, the LC method and the PE method, in order to effectively use critical experiments and to enhance the applicability of the bias factor method for the improvement of the prediction accuracy of neutronic characteristics of a target core. Both methods utilize a number of critical experimental results and produce a semifictitious experimental value with them. The LC and PE methods define the semifictitious experimental values by a linear combination of experimental values and the product of exponentiated experimental values, respectively, and the corresponding semifictitious calculation values by those of calculation values. A bias factor is defined by the ratio of the semifictitious experimental value to the semifictitious calculation value in both methods. We formulate how to determine weights for the LC method and exponents for the PE method in order to minimize the variance of the design prediction value obtained by multiplying the design calculation value by the bias factor. From a theoretical comparison of these new methods with the conventional method which utilizes a single experimental result and the generalized bias factor method which was previously proposed to utilize a number of experimental results, it is concluded that the PE method is the most useful method for improving the prediction accuracy. The main advantages of the PE method are summarized as follows. The prediction accuracy is necessarily improved compared with the design calculation value even when experimental results include large experimental errors. This is a special feature that the other methods do not have. The prediction accuracy is most effectively improved by utilizing all the experimental results. From these facts, it can be said that the PE method effectively utilizes all the experimental results and has a possibility to make a full-scale-mockup experiment unnecessary with the use of existing and future benchmark

  4. Critical node lifetimes in random networks via the Chen-Stein method

    NARCIS (Netherlands)

    Franceschetti, M.; Meester, R.W.J.

    2006-01-01

    This correspondence considers networks where nodes are connected randomly and can fail at random times. It provides scaling laws that allow to find the critical time at which isolated nodes begin to appear in the system as its size tends to infinity. Applications are in the areas of sensor and

  5. Making the Invisible Visible: Advancing Quantitative Methods in Higher Education Using Critical Race Theory and Intersectionality

    Science.gov (United States)

    López, Nancy; Erwin, Christopher; Binder, Melissa; Chavez, Mario Javier

    2018-01-01

    We appeal to critical race theory and intersectionality to examine achievement gaps at a large public university in the American southwest from 2000 to 2015. Using white, high-income women as our reference group, we report linear combinations of marginal effects for six-year graduation rates and developmental course taking across 20 distinct…

  6. Critically Conscious Learning: Using Participatory Action Research Methods to Engage Students

    Science.gov (United States)

    Shahnazarian, Armen

    2017-01-01

    As outlined by many of the social and political movements happening around us today, now more than ever, youth need to be critically conscious of their world in order to navigate it successfully. The Toronto District School Board, where Armen Shahnazarian teaches uses the hybrid model of culturally responsive and relevant pedagogy (CRRP), based on…

  7. Using Critical Thinking Teaching Methods to Increase Student Success: An Action Research Project

    Science.gov (United States)

    Nold, Herbert

    2017-01-01

    Numerous studies and United States Department of Education reports indicate that university graduates lack critical thinking and problem solving skills that are needed for success in both the classroom and the modern workplace. Success in the classroom and workplace is a function of many attributes that change with the situation, but the ability…

  8. Critical Emergency Medicine Procedural Skills: A Comparative Study of Methods for Teaching and Assessment.

    Science.gov (United States)

    Chapman, Dane M.; And Others

    Three critical procedural skills in emergency medicine were evaluated using three assessment modalities--written, computer, and animal model. The effects of computer practice and previous procedure experience on skill competence were also examined in an experimental sequential assessment design. Subjects were six medical students, six residents,…

  9. Method of V ampersand V for safety-critical software in NPPs

    International Nuclear Information System (INIS)

    Kim, Jang-Yeol; Lee, Jang-Soo; Kwon, Kee-Choon

    1997-01-01

    Safety-critical software is software used in systems in which a failure could affect personal or equipment safety or result in large financial or social loss. Examples of systems using safety-critical software are systems such as plant protection systems in nuclear power plants (NPPs), process control systems in chemical plants, and medical instruments such as the Therac-25 medical accelerator. This paper presents verification and validation (V ampersand V) methodology for safety-critical software in NPP safety systems. In addition, it addresses issues related to NPP safety systems, such as independence parameters, software safety analysis (SSA) concepts, commercial off-the-shelf (COTS) software evaluation criteria, and interrelationships among software and system assurance organizations. It includes the concepts of existing industrial standards on software V ampersand V, Institute of Electrical and Electronics Engineers (IEEE) Standards 1012 and 1059. This safety-critical software V ampersand V methodology covers V ampersand V scope, a regulatory framework as part of its acceptance criteria, V ampersand V activities and task entrance and exit criteria, reviews and audits, testing and quality assurance records of V ampersand V material, configuration management activities related to V ampersand V, and software V ampersand V (SVV) plan (SVVP) production

  10. M-OSCE as a method to measure dental hygiene students' critical thinking: a pilot study.

    Science.gov (United States)

    McComas, Martha J; Wright, Rebecca A; Mann, Nancy K; Cooper, Mary D; Jacks, Mary E

    2013-04-01

    Educators in all academic disciplines have been encouraged to utilize assessment strategies to evaluate students' critical thinking. The purpose of this study was to assess the viability of the modified objective structured clinical examination (m-OSCE) to evaluate critical thinking in dental hygiene education. This evaluation utilized a convenience sample of senior dental hygiene students. Students participated in the m-OSCE in which portions of a patient case were revealed at four stations. The exam consisted of multiple-choice questions intended to measure students' ability to utilize critical thinking skills. Additionally, there was one fill-in-the-blank question and a treatment plan that was completed at the fifth station. The results of this study revealed that the m-OSCE did not reliably measure dental hygiene students' critical thinking. Statistical analysis found no satisfactory reliability within the multiple-choice questions and moderately reliable results within the treatment planning portion of the examination. In addition, the item analysis found gaps in students' abilities to transfer clinical evidence/data to basic biomedical knowledge as demonstrated through the multiple-choice questioning results. This outcome warrants further investigation of the utility of the m-OSCE, with a focus on modifications to the evaluation questions, grading rubric, and patient case.

  11. Method of calculation of critical values of financial indicators for developing food security strategy

    Science.gov (United States)

    Aigyl Ilshatovna, Sabirova; Svetlana Fanilevna, Khasanova; Vildanovna, Nagumanova Regina

    2018-05-01

    On the basis of decision making theory (minimax and maximin approaches) the authors propose a technique with the results of calculations of the critical values of effectiveness indicators of agricultural producers in the Republic of Tatarstan for 2013-2015. There is justified necessity of monitoring the effectiveness of the state support and the direction of its improvement.

  12. Applicability of object-oriented design methods and C++ to safety-critical systems

    International Nuclear Information System (INIS)

    Cuthill, B.B.

    1994-01-01

    This paper reports on a study identifying risks and benefits of using a software development methodology containing object-oriented design (OOD) techniques and using C++ as a programming language relative to selected features of safety-critical systems development. These features are modularity, functional diversity, removing ambiguous code, traceability, and real-time performance

  13. Rapid method of calculating the fluence and spectrum of neutrons from a critical assembly and the resulting dose

    International Nuclear Information System (INIS)

    Bessis, J.

    1977-01-01

    The proposed calculation method is unsophisticated but rapid. The first part (computer code CRITIC), which is based on the Fermi age equation, evaluates the number of neutrons per fission emitted from a moderated critical assembly and their energy spectrum. The second part (computer code NARCISSE), which uses the current albedo for concrete, evaluates the product of neutron reflection on the walls and calculates the fluence resulting at any point in the room and its energy distribution by 21 groups. The results obtained are shown to compare satisfactorily with those obtained through the use of a Monte Carlo program

  14. "Pre-schoolers in the playground" an outdoor physical activity intervention for children aged 18 months to 4 years old: study protocol for a pilot cluster randomised controlled trial.

    Science.gov (United States)

    Barber, Sally E; Jackson, Cath; Akhtar, Shaheen; Bingham, Daniel D; Ainsworth, Hannah; Hewitt, Catherine; Richardson, Gerry; Summerbell, Carolyn D; Pickett, Kate E; Moore, Helen J; Routen, Ash C; O'Malley, Claire L; Brierley, Shirley; Wright, John

    2013-10-09

    The pre-school years are considered critical for establishing healthy lifestyle behaviours such as physical activity. Levels of physical activity track through childhood into adulthood, thus establishing habitual physical activity early in life is vital. Time spent outdoors is associated with greater physical activity and playground interventions have been shown to increase physical activity in school aged children. There are few pre-school, playground-based interventions, and evaluations of these have found mixed results. A recent report published by the UK Chief Medical Officer (CMO) highlighted that new interventions to promote movement in the early years (0-5 years old) are needed. The aim of this study is to undertake a pilot cluster randomised controlled trial (RCT) of an outdoor playground-based physical activity intervention for parents and their children aged 18 months to 4 years old ("Pre-schoolers in the Playground"; PiP) and to assess the feasibility of conducting a full scale cluster RCT. The PiP intervention is grounded in behavioural theory (Social Cognitive Theory), and is in accordance with the CMO guidance for physical activity in the early years. It is informed by existing literature and data collected from focus groups with parents. One hundred and fifty pre-school children affiliated to 10 primary schools will be recruited. Schools will be randomised to either the PiP intervention arm or the control arm (usual practice). Children in the intervention arm will be invited to attend three 30 minute outdoor play sessions per week for 30 weeks (3 school terms) at the school. Feasibility will be assessed by examining recruitment rates, attendance, attrition, acceptability of the trial and of the PiP intervention to parents, fidelity of intervention implementation, capability and capacity for schools to deliver the intervention. Health outcomes and the feasibility of outcome measurement tools will be assessed. These include physical activity via

  15. THE EFFECTS OF PBL METHOD USING THE HYPERMEDIA TO THE STUDENTS’ CRITICAL THINKING SKILL ON THE SOCIAL STUDIES SUBJECT

    Directory of Open Access Journals (Sweden)

    Dicky Iranto

    2014-10-01

    Full Text Available Education as human’s process to gain knowledge is very important to create thinking skill for the human being. Related to that thing, implemented the learning with Problem Based Learning method which is the learning that is oriented to enhance the students’ critical thinking skill. In the constructivism learning theory, the students should be able to construct the knowledge through problem solving so they got the truth which is useful for the existence. This research is using the quasi experiment method with non-equivalent group design. The conclusion of this research shows that there is enhancement to the students’ critical thinking skill significantly and suggested to use this method on another topic, schools gives the hypermedia facilities, and researching another learning competences.

  16. Physical methods for the treatment of fever in critically ill patients: a randomized controlled trial.

    Science.gov (United States)

    Salgado, Patrícia de Oliveira; Silva, Ludmila Christiane Rosa da; Silva, Priscila Marinho Aleixo; Chianca, Tânia Couto Machado

    2016-01-01

    To evaluate the effects of physical methods of reducing body temperature (ice pack and warm compression) in critically ill patients with fever. A randomized clinical trial involving 102 adult patients with tympanic temperature ≥ 38.3°C of an infectious focus, and randomized into three groups: Intervention I - ice pack associated with antipyretic; Intervention II - warm compress associated with antipyretic; and Control - antipyretic. Tympanic temperature was measured at 15 minute intervals for 3 hours. The effect of the interventions was evaluated through the Mann-Whitney test and Survival Analysis. "Effect size" calculation was carried out. Patients in the intervention groups I and II presented greater reduction in body temperature. The group of patients receiving intervention I presented tympanic temperature below 38.3°C at 45 minutes of monitoring, while the value for control group was lower than 38.3°C starting at 60 minutes, and those who received intervention II had values lower than 38.3°C at 75 minutes of monitoring. No statistically significant difference was found between the interventions, but with the intervention group I patients showed greater reduction in tympanic temperature compared to the other groups. Brazilian Registry of Clinical Trials: RBR-2k3kbq. Avaliar o efeito de métodos físicos (bolsa de gelo e compressa morna) na redução da temperatura corporal de pacientes críticos com febre. Ensaio clínico randomizado com 102 pacientes adultos e temperatura timpânica ≥ 38,3°C de foco infeccioso, aleatorizados em três grupos: Intervenção I ‒ bolsa de gelo associada a antitérmico; Intervenção II ‒ compressa morna associada a antitérmico; e Controle ‒ antitérmico. A temperatura timpânica foi mensurada em intervalos de 15 minutos durante 3 horas. O efeito das intervenções foi avaliado pelo teste Mann-Whitney e Análise de Sobrevivência. Cálculo do "Effect size" foi procedido. Os pacientes dos grupos Intervenção I e II

  17. Serbian music criticism in the first half of the twentieth century: Its canon, its method and its educational role

    Directory of Open Access Journals (Sweden)

    Vasić Aleksandar

    2008-01-01

    Full Text Available Serbian music criticism became a subject of professional music critics at the beginning of the twentieth century, after being developed by music amateurs throughout the whole previous century. The Serbian Literary Magazine (1901- 1914, 1920-1941, the forum of the Serbian modernist writers in the early 1900s, had a crucial role in shaping the Serbian music criticism and essayistics of the modern era. The Serbian elite musicians wrote for the SLM and therefore it reflects the most important issues of the early twentieth century Serbian music. The SLM undertook the mission of educating its readers. The music culture of the Serbian public was only recently developed. The public needed an introduction into the most important features of the European music, as well as developing its own taste in music. This paper deals with two aspects of the music criticism in the SLM, in view of its educational role: the problem of virtuosity and the method used by music critics in this magazine. The aesthetic canon of the SLM was marked by decisively negative attitude towards the virtuosity. Mainly concerned by educating the Serbian music public in the spirit of the highest music achievements in Europe, the music writers of the SLM criticized both domestic and foreign performers who favoured virtuosity over the 'essence' of music. Therefore, Niccolò Paganini, Franz Liszt, and even Peter Tchaikowsky with his Violin concerto became the subject of the magazine's criticism. However their attitude towards the interpreters with both musicality and virtuoso technique was always positive. That was evident in the writings on Jan Kubelík. This educational mission also had its effect on the structure of critique writings in the SLM. In their wish to inform the Serbian public on the European music (which they did very professionally, the critics gave much more information on biographies, bibliographies and style of the European composers, than they valued the interpretation

  18. Research on consequence analysis method for probabilistic safety assessment of nuclear fuel facilities (5). Evaluation method and trial evaluation of criticality accident

    International Nuclear Information System (INIS)

    Yamane, Yuichi; Abe, Hitoshi; Nakajima, Ken; Hayashi, Yoshiaki; Arisawa, Jun; Hayami, Satoru

    2010-01-01

    A special committee of 'Research on the analysis methods for accident consequence of nuclear fuel facilities (NFFs)' was organized by the Atomic Energy Society of Japan (AESJ) under the entrustment of Japan Atomic Energy Agency (JAEA). The committee aims to research on the state-of-the-art consequence analysis method for the Probabilistic Safety Assessment (PSA) of NFFs, such as fuel reprocessing and fuel fabrication facilities. The objectives of this research are to obtain information useful for establishing quantitative performance objectives and to demonstrate risk-informed regulation through qualifying issues needed to be resolved for applying PSA to NFFs. The research activities of the committee were mainly focused on the consequence analysis method for postulated accidents with potentially large consequences in NFFs, e.g., events of criticality, spill of molten glass, hydrogen explosion, boiling of radioactive solution and fire (including the rapid decomposition of TBP complexes), resulting in the release of radioactive materials to the environment. The results of the research were summarized in a series of six reports, which consist of a review report and five technical ones. In this report, the evaluation methods of criticality accident, such as simplified methods, one-point reactor kinetics codes and quasi-static method, were investigated and their features were summarized to provide information useful for the safety evaluation of NFFs. In addition, several trial evaluations were performed for a hypothetical scenario of criticality accident using the investigated methods, and their results were compared. The release fraction of volatile fission products in a criticality accident was also investigated. (author)

  19. Correction method for critical extrapolation of control-rods-rising during physical start-up of reactor

    International Nuclear Information System (INIS)

    Zhang Fan; Chen Wenzhen; Yu Lei

    2008-01-01

    During physical start-up of nuclear reactor, the curve got by lifting the con- trol rods to extrapolate to the critical state is often in protruding shape, by which the supercritical phenomena is led. In the paper, the reason why the curve was in protruding was analyzed. A correction method was introduced, and the calculations were carried out by the practical data used in a nuclear power plant. The results show that the correction method reverses the protruding shape of the extrapolating curve, and the risk of reactor supercritical phenomena can be reduced using the extrapolated curve got by the correction method during physical start-up of the reactor. (authors)

  20. Common method biases in behavioral research: a critical review of the literature and recommended remedies.

    Science.gov (United States)

    Podsakoff, Philip M; MacKenzie, Scott B; Lee, Jeong-Yeon; Podsakoff, Nathan P

    2003-10-01

    Interest in the problem of method biases has a long history in the behavioral sciences. Despite this, a comprehensive summary of the potential sources of method biases and how to control for them does not exist. Therefore, the purpose of this article is to examine the extent to which method biases influence behavioral research results, identify potential sources of method biases, discuss the cognitive processes through which method biases influence responses to measures, evaluate the many different procedural and statistical techniques that can be used to control method biases, and provide recommendations for how to select appropriate procedural and statistical remedies for different types of research settings.

  1. An evaluation method of critical velocity for self-excited vibration of cross-shaped tube bundle in cross flow

    International Nuclear Information System (INIS)

    Inada, Fumio; Nishihara, Takashi; Yasuo, Akira; Morita, Ryo

    2002-01-01

    The applicability of the cross-shaped tube bundle as a lower plenum component of pressure vessel is examined to develop a next generation LWR in Japanese electric utilities. The flow-induced vibration characteristics are not understood well. Methods to evaluate turbulence induced vibration and vortex induced vibration were proposed by CRIEPI. In this study, vibration response is obtained experimentally to propose a method to evaluate self-excited vibration of cross-shaped tube bundle. The self-excited vibration was found to be generated when nondimensional flow velocity was above a critical value. The nondimensional critical velocity of normal configuration is 15% smaller than that of staggered configuration, which means that the nondimensional critical velocity of normal configuration can give conservative evaluation. The result of Reynolds number Re=6.2 x 10 4 agrees well with that of Re=6.8 x 10 5 , in which region, the effect of Reynolds number on the critical velocity is small. (author)

  2. Enhancing Critical Thinking Skills for Army Leaders Using Blended-Learning Methods

    Science.gov (United States)

    2013-01-01

    Distance . . . . . . . . . . . . . . . . 84 Successful Programs Use a Variety of Methods to Foster Student Engagement and Success in Online Interactive...sometimes interact in ways that inhibit collaborative learning. Successful Programs Use a Variety of Methods to Foster Student Engagement and...Programs Use a Variety of Methods to Foster Student Engagement and Success in Online Interactive Activities We looked to the case studies for

  3. Validity in Mixed Methods Research in Education: The Application of Habermas' Critical Theory

    Science.gov (United States)

    Long, Haiying

    2017-01-01

    Mixed methods approach has developed into the third methodological movement in educational research. Validity in mixed methods research as an important issue, however, has not been examined as extensively as that of quantitative and qualitative research. Additionally, the previous discussions of validity in mixed methods research focus on research…

  4. Critical Communication Pedagogy and Service Learning in a Mixed-Method Communication Research Course

    Science.gov (United States)

    Rudick, C. Kyle; Golsan, Kathryn B.; Freitag, Jennifer

    2018-01-01

    Course: Mixed-Method Communication Research Methods. Objective: The purpose of this semester-long activity is to provide students with opportunities to cultivate mixed-method communication research skills through a social justice-informed service-learning format. Completing this course, students will be able to: recognize the unique strengths of…

  5. Research Methods Teaching in Vocational Environments: Developing Critical Engagement with Knowledge?

    Science.gov (United States)

    Gray, C.; Turner, R.; Sutton, C.; Petersen, C.; Stevens, S.; Swain, J.; Esmond, B.; Schofield, C.; Thackeray, D.

    2015-01-01

    Knowledge of research methods is regarded as crucial for the UK economy and workforce. However, research methods teaching is viewed as a challenging area for lecturers and students. The pedagogy of research methods teaching within universities has been noted as underdeveloped, with undergraduate students regularly expressing negative dispositions…

  6. Discussion of Science and Math Teaching Methods: criticism and possibilities in teaching practices

    Directory of Open Access Journals (Sweden)

    Elizabeth Gerhardt Manfredo

    2005-06-01

    Full Text Available This paper presents a discussion of practices among Science and Math teachers in Brazilian Basic Education. Analysis focuses on criticism over teaching practices throughout Basic Education which includes Children, Primary and Medium levels. Discussion highlights the interdisciplinary and educational projects as the most chosen tool for reflective practices. Most educational problems must be solved by the use of shared theoretical choices and investigative methodological approach. Such choices ought to be made during teachers' continuing trainning based on a researcher-teacher action as it provides ways for methodological changes in Sciences and Math Education in the Country

  7. Predictors of post-traumatic stress disorder following critical illness: A mixed methods study.

    Science.gov (United States)

    Battle, Ceri E; James, Karen; Bromfield, Tom; Temblett, Paul

    2017-11-01

    Post-traumatic stress disorder has been reported in survivors of critical illness. The aim of this study was to investigate the predictors of post-traumatic stress disorder in survivors of critical illness. Patients attending the intensive care unit (ICU) follow-up clinic completed the UK-Post-Traumatic Stress Syndrome 14-Questions Inventory and data was collected from their medical records. Predictors investigated included age, gender, Apache II score, ICU length of stay, pre-illness psychopathology; delirium and benzodiazepine administration during ICU stay and delusional memories of the ICU stay following discharge. A total of 198 patients participated, with 54 (27%) patients suffering with post-traumatic stress disorder. On multivariable logistic regression, the significant predictors of post-traumatic stress disorder were younger age, lower Apache II score, pre-illness psychopathology and delirium during the ICU stay. The predictors of post-traumatic stress disorder in this study concur with previous research however a lower Apache II score has not been previously reported.

  8. Method of preventing criticality of fresh fuel assembly in storage facility

    International Nuclear Information System (INIS)

    Kawamura, Makoto.

    1990-01-01

    With an aim of improving the operation efficiency of a reactor, extention of the operation cycle by increasing U 235 enrichment degree of fuel uranium is planned. However, along with the increase of the enrichment degree of the fuel uranium, there occurs a problem of criticality upon fuel handling. Then, in the present invention, boric acid incorporating B-10 of great neutron absorption effect are packed with water soluble polymeric materials which are further packed with a fuel packing sheet, or the water soluble polymeric materials incorporating boric acids are packed with fuel packing sheets which are disposed to a fresh fuel assembly and stored in a store house as they are. The fuel packing sheet is a perforated sheet having a plurality of water intruding pores. Then, if water should intrude to the store house accidentally, the water soluble polymeric materials are dissolved, so that the intruded water is converted into aqueous boric acid easily and absorbs neutrons effectively to thereby attain the prevention of criticality. (T.M.)

  9. Comparison of methods of alert acknowledgement by critical care clinicians in the ICU setting

    Directory of Open Access Journals (Sweden)

    Andrew M. Harrison

    2017-03-01

    Full Text Available Background Electronic Health Record (EHR-based sepsis alert systems have failed to demonstrate improvements in clinically meaningful endpoints. However, the effect of implementation barriers on the success of new sepsis alert systems is rarely explored. Objective To test the hypothesis time to severe sepsis alert acknowledgement by critical care clinicians in the ICU setting would be reduced using an EHR-based alert acknowledgement system compared to a text paging-based system. Study Design In one arm of this simulation study, real alerts for patients in the medical ICU were delivered to critical care clinicians through the EHR. In the other arm, simulated alerts were delivered through text paging. The primary outcome was time to alert acknowledgement. The secondary outcomes were a structured, mixed quantitative/qualitative survey and informal group interview. Results The alert acknowledgement rate from the severe sepsis alert system was 3% (N = 148 and 51% (N = 156 from simulated severe sepsis alerts through traditional text paging. Time to alert acknowledgement from the severe sepsis alert system was median 274 min (N = 5 and median 2 min (N = 80 from text paging. The response rate from the EHR-based alert system was insufficient to compare primary measures. However, secondary measures revealed important barriers. Conclusion Alert fatigue, interruption, human error, and information overload are barriers to alert and simulation studies in the ICU setting.

  10. THE EFFECTS OF PBL METHOD USING THE HYPERMEDIA TO THE STUDENTS’ CRITICAL THINKING SKILL ON THE SOCIAL STUDIES SUBJECT

    OpenAIRE

    Iranto, Dicky; Suparno, S

    2014-01-01

    Education as human’s process to gain knowledge is very important to create thinking skill for the human being. Related to that thing, implemented the learning with Problem Based Learning method which is the learning that is oriented to enhance the students’ critical thinking skill. In the constructivism learning theory, the students should be able to construct the knowledge through problem solving so they got the truth which is useful for the existence. This research is using the quasi experi...

  11. Analysis of mixed oxides critical experiments using the Hammer-Technion code with self-shielding treatment by Bondarenko method

    International Nuclear Information System (INIS)

    Abe, Alfredo Y.; Santos, Adimir dos

    1995-01-01

    The present work summarizes the verification of the treatment of self-shielding based on Bondarenko method in HAMMER-TECHNION cell code for the Pu O 2 -U O 2 critical system using JENDL-3 nuclear data library. The results obtained are in excellent agreement with the original treatment of self-shielding employed by HAMMER-TECHNION cell code. (author). 9 refs, 1 fig, 9 tabs

  12. A human reliability based usability evaluation method for safety-critical software

    International Nuclear Information System (INIS)

    Boring, R. L.; Tran, T. Q.; Gertman, D. I.; Ragsdale, A.

    2006-01-01

    Boring and Gertman (2005) introduced a novel method that augments heuristic usability evaluation methods with that of the human reliability analysis method of SPAR-H. By assigning probabilistic modifiers to individual heuristics, it is possible to arrive at the usability error probability (UEP). Although this UEP is not a literal probability of error, it nonetheless provides a quantitative basis to heuristic evaluation. This method allows one to seamlessly prioritize and identify usability issues (i.e., a higher UEP requires more immediate fixes). However, the original version of this method required the usability evaluator to assign priority weights to the final UEP, thus allowing the priority of a usability issue to differ among usability evaluators. The purpose of this paper is to explore an alternative approach to standardize the priority weighting of the UEP in an effort to improve the method's reliability. (authors)

  13. Development of an asymmetric multiple-position neutron source (AMPNS) method to monitor the criticality of a degraded reactor core

    International Nuclear Information System (INIS)

    Kim, S.S.; Levine, S.H.

    1985-01-01

    An analytical/experimental method has been developed to monitor the subcritical reactivity and unfold the k/sub infinity/ distribution of a degraded reactor core. The method uses several fixed neutron detectors and a Cf-252 neutron source placed sequentially in multiple positions in the core. Therefore, it is called the Asymmetric Multiple Position Neutron Source (AMPNS) method. The AMPNS method employs nucleonic codes to analyze the neutron multiplication of a Cf-252 neutron source. An optimization program, GPM, is utilized to unfold the k/sub infinity/ distribution of the degraded core, in which the desired performance measure minimizes the error between the calculated and the measured count rates of the degraded reactor core. The analytical/experimental approach is validated by performing experiments using the Penn State Breazeale TRIGA Reactor (PSBR). A significant result of this study is that it provides a method to monitor the criticality of a damaged core during the recovery period

  14. Direct optical band gap measurement in polycrystalline semiconductors: A critical look at the Tauc method

    International Nuclear Information System (INIS)

    Dolgonos, Alex; Mason, Thomas O.; Poeppelmeier, Kenneth R.

    2016-01-01

    The direct optical band gap of semiconductors is traditionally measured by extrapolating the linear region of the square of the absorption curve to the x-axis, and a variation of this method, developed by Tauc, has also been widely used. The application of the Tauc method to crystalline materials is rooted in misconception–and traditional linear extrapolation methods are inappropriate for use on degenerate semiconductors, where the occupation of conduction band energy states cannot be ignored. A new method is proposed for extracting a direct optical band gap from absorption spectra of degenerately-doped bulk semiconductors. This method was applied to pseudo-absorption spectra of Sn-doped In 2 O 3 (ITO)—converted from diffuse-reflectance measurements on bulk specimens. The results of this analysis were corroborated by room-temperature photoluminescence excitation measurements, which yielded values of optical band gap and Burstein–Moss shift that are consistent with previous studies on In 2 O 3 single crystals and thin films. - Highlights: • The Tauc method of band gap measurement is re-evaluated for crystalline materials. • Graphical method proposed for extracting optical band gaps from absorption spectra. • The proposed method incorporates an energy broadening term for energy transitions. • Values for ITO were self-consistent between two different measurement methods.

  15. Critical review of methods for risk ranking of food-related hazards, based on risks for human health.

    Science.gov (United States)

    Van der Fels-Klerx, H J; Van Asselt, E D; Raley, M; Poulsen, M; Korsgaard, H; Bredsdorff, L; Nauta, M; D'agostino, M; Coles, D; Marvin, H J P; Frewer, L J

    2018-01-22

    This study aimed to critically review methods for ranking risks related to food safety and dietary hazards on the basis of their anticipated human health impacts. A literature review was performed to identify and characterize methods for risk ranking from the fields of food, environmental science and socio-economic sciences. The review used a predefined search protocol, and covered the bibliographic databases Scopus, CAB Abstracts, Web of Sciences, and PubMed over the period 1993-2013. All references deemed relevant, on the basis of predefined evaluation criteria, were included in the review, and the risk ranking method characterized. The methods were then clustered-based on their characteristics-into eleven method categories. These categories included: risk assessment, comparative risk assessment, risk ratio method, scoring method, cost of illness, health adjusted life years (HALY), multi-criteria decision analysis, risk matrix, flow charts/decision trees, stated preference techniques and expert synthesis. Method categories were described by their characteristics, weaknesses and strengths, data resources, and fields of applications. It was concluded there is no single best method for risk ranking. The method to be used should be selected on the basis of risk manager/assessor requirements, data availability, and the characteristics of the method. Recommendations for future use and application are provided.

  16. Critical Analysis of Non-Nuclear Electron-Density Maxima and the Maximum Entropy Method

    NARCIS (Netherlands)

    de Vries, R.Y.; Briels, Willem J.; Feil, D.; Feil, D.

    1996-01-01

    Experimental evidence for the existence of non-nuclear maxima in charge densities is questioned. It is shown that the non-nuclear maxima reported for silicon are artifacts of the maximum entropy method that was used to analyze the x-ray diffraction data. This method can be improved by the use of

  17. Knowledge Transmission versus Social Transformation: A Critical Analysis of Purpose in Elementary Social Studies Methods Textbooks

    Science.gov (United States)

    Butler, Brandon M.; Suh, Yonghee; Scott, Wendy

    2015-01-01

    In this article, the authors investigate the extent to which 9 elementary social studies methods textbooks present the purpose of teaching and learning social studies. Using Stanley's three perspectives of teaching social studies for knowledge transmission, method of intelligence, and social transformation; we analyze how these texts prepare…

  18. Critical analysis of imaging methods for the detection and diagnosis of breast cancer

    International Nuclear Information System (INIS)

    Mendonca, Maria Helena Siqueira

    1999-01-01

    Breast cancer is a significant health problem. Early diagnosis of the disease is mandatory to increase the effectiveness of the treatment, to augment the chances of cure and to permit conservative surgery. The use of imaging methods is essential in the early diagnosis of the disease. Imaging methods advantages and disadvantages, use and limitations, specificity and sensitivity are presented and discussed. (author)

  19. Method and apparatus for preventing inadvertent criticality in a nuclear fueled electric power generating unit

    International Nuclear Information System (INIS)

    Tuley, C.R.; Bauman, D.A.; Neuner, J.A.; Feilchenfeld, M.M.; Greenberg, L.

    1984-01-01

    An inadvertent approach to criticality in a nuclear fueled electric power generating unit is detected and an alarm is generated through on-line monitoring of the neutron flux. The difficulties of accurately measuring the low levels of neutron flux in a subcritical reactor are overcome by the use of a microcomputer which continuously generates average flux count rate signals for incremental time periods from thousands of samples taken during each such period and which serially stores the average flux count rate signals for a preselected time interval. At the end of each incremental time period, the microcomputer compares the latest average flux count rate signal with the oldest, and preferably each of the intervening stored values, and if it exceeds any of them by at least a preselected multiplication factor, an alarm is generated. (author)

  20. Methods for forewarning of critical condition changes in monitoring civil structures

    Science.gov (United States)

    Abercrombie, Robert K.; Hively, Lee M.

    2013-04-02

    Sensor modules (12) including accelerometers (20) are placed on a physical structure (10) and tri-axial accelerometer data is converted to mechanical power (P) data (41) which then processed to provide a forewarning (57) of a critical event concerning the physical structure (10). The forewarning is based on a number of occurrences of a composite measure of dissimilarity (C.sub.i) exceeding a forewarning threshold over a defined sampling time; and a forewarning signal (58) is provided to a human observer through a visual, audible or tangible signal. A forewarning of a structural failure can also be provided based on a number of occurrences of (C.sub.i) above a failure value threshold.

  1. A Critical Comparison of Methods for the Analysis of Indigo in Dyeing Liquors and Effluents

    Directory of Open Access Journals (Sweden)

    Valentina Buscio

    2014-08-01

    Full Text Available Indigo is one of the most important dyes in the textile industry. The control of the indigo concentration in dyeing liquors and effluents is an important tool to ensure the reproducibility of the dyed fabrics and also to establish the efficiency of the wastewater treatment. In this work, three analytical methods were studied and validated with the aim to select a reliable, fast and automated method for the indigo dye determination. The first method is based on the extraction of the dye, with chloroform, in its oxidized form. The organic solution is measured by Ultraviolet (UV-visible spectrophotometry at 604 nm. The second method determines the concentration of indigo in its leuco form in aqueous medium by UV-visible spectrophotometry at 407 nm. Finally, in the last method, the concentration of indigo is determined by redox titration with potassium hexacyanoferrate (K3(Fe(CN6. The results indicated that the three methods that we studied met the established acceptance criteria regarding accuracy and precision. However, the third method was considered the most adequate for application on an industrial scale due to its wider work range, which provides a significant advantage over the others.

  2. A critical pressure based panel method for prediction of unsteady loading of marine propellers under cavitation

    International Nuclear Information System (INIS)

    Liu, P.; Bose, N.; Colbourne, B.

    2002-01-01

    A simple numerical procedure is established and implemented into a time domain panel method to predict hydrodynamic performance of marine propellers with sheet cavitation. This paper describes the numerical formulations and procedures to construct this integration. Predicted hydrodynamic loads were compared with both a previous numerical model and experimental measurements for a propeller in steady flow. The current method gives a substantial improvement in thrust and torque coefficient prediction over a previous numerical method at low cavitation numbers of less than 2.0, where severe cavitation occurs. Predicted pressure coefficient distributions are also presented. (author)

  3. A critical analysis of some popular methods for the discretisation of the gradient operator in finite volume methods

    Science.gov (United States)

    Syrakos, Alexandros; Varchanis, Stylianos; Dimakopoulos, Yannis; Goulas, Apostolos; Tsamopoulos, John

    2017-12-01

    Finite volume methods (FVMs) constitute a popular class of methods for the numerical simulation of fluid flows. Among the various components of these methods, the discretisation of the gradient operator has received less attention despite its fundamental importance with regards to the accuracy of the FVM. The most popular gradient schemes are the divergence theorem (DT) (or Green-Gauss) scheme and the least-squares (LS) scheme. Both are widely believed to be second-order accurate, but the present study shows that in fact the common variant of the DT gradient is second-order accurate only on structured meshes whereas it is zeroth-order accurate on general unstructured meshes, and the LS gradient is second-order and first-order accurate, respectively. This is explained through a theoretical analysis and is confirmed by numerical tests. The schemes are then used within a FVM to solve a simple diffusion equation on unstructured grids generated by several methods; the results reveal that the zeroth-order accuracy of the DT gradient is inherited by the FVM as a whole, and the discretisation error does not decrease with grid refinement. On the other hand, use of the LS gradient leads to second-order accurate results, as does the use of alternative, consistent, DT gradient schemes, including a new iterative scheme that makes the common DT gradient consistent at almost no extra cost. The numerical tests are performed using both an in-house code and the popular public domain partial differential equation solver OpenFOAM.

  4. Critical review of methods for the estimation of actual evapotranspiration in hydrological models

    CSIR Research Space (South Africa)

    Jovanovic, Nebojsa

    2012-01-01

    Full Text Available The chapter is structured in three parts, namely: i) A theoretical overview of evapotranspiration processes, including the principle of atmospheric demand-soil water supply, ii) A review of methods and techniques to measure and estimate actual...

  5. Approach suitable for screening estimation methods for critical properties of heavy compounds

    DEFF Research Database (Denmark)

    Zbogar, A.; vidal da Silva Lopes, F.; Kontogeorgis, Georgios

    2006-01-01

    ) is in agreement with their validation via the proposed equation. Similar results have been obtained for other compounds. Both group-contribution methods are of equal accuracy for heavy alkenes and acids, provided that experimental boiling point temperatures are available for the Joback method. If such data...... the very heavy and complex ones, follow the trend suggested by this equation. This equation can be used for testing existing group-contribution estimation methods. It is shown here that direct comparison of the Joback and Constantinou-Gani methods for two families of compounds (alkenes and carboxylic acids......- and diacids, alkenes, cyclo/phenylalkanes, and squalane). This and previous validations verify that this correlation has a much broader application range, up to (T-c/p(c)) ratios of 200, than the data used in its development (compounds with ratios up to 100). it seems that most organic compounds, including...

  6. Comparison of critical methods developed for fatty acid analysis: A review.

    Science.gov (United States)

    Wu, Zhuona; Zhang, Qi; Li, Ning; Pu, Yiqiong; Wang, Bing; Zhang, Tong

    2017-01-01

    Fatty acids are important nutritional substances and metabolites in living organisms. These acids are abundant in Chinese herbs, such as Brucea javanica, Notopterygium forbesii, Isatis tinctoria, Astragalus membranaceus, and Aconitum szechenyianum. This review illustrates the types of fatty acids and their significant roles in the human body. Many analytical methods are used for the qualitative and quantitative evaluation of fatty acids. Some of the methods used to analyze fatty acids in more than 30 kinds of plants, drugs, and other samples are presented in this paper. These analytical methods include gas chromatography, liquid chromatography, near-infrared spectroscopy, and NMR spectroscopy. The advantages and disadvantages of these techniques are described and compared. This review provides a valuable reference for establishing methods for fatty acid determination. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. A critical comparison of electrical methods for measuring spin-orbit torques

    Science.gov (United States)

    Zhang, Xuanzi; Hung, Yu-Ming; Rehm, Laura; Kent, Andrew D.

    Direct (DC) and alternating current (AC) transport measurements of spin-orbit torques (SOTs) in heavy metal-ferromagnet heterostructure with perpendicular magnetic anisotropy have been proposed and demonstrated. A DC method measures the change of perpendicular magnetization component while an AC method probes the first and second harmonic magnetization oscillation in responses to an AC current (~1 kHz). Here we conduct both types of measurements on β-Ta/CoFeB/MgO in the form of patterned Hall bars (20 μm linewidth) and compare the results. Experiments results are qualitatively in agreement with a macro spin model including Slonzewski-like and a field-like SOTs. However, the effective field from the ac method is larger than that obtained from the DC method. We discuss the possible origins of the discrepancy and its implications for quantitatively determining SOTs. Research supported by the SRC-INDEX program, NSF-DMR-1309202 and NYU-DURF award.

  8. An Introduction to Formal Methods for the Development of Safety-critical Applications

    DEFF Research Database (Denmark)

    Haxthausen, Anne Elisabeth

    2010-01-01

    This report is a delivery to The Danish Government’s railway authority, Trafikstyrelsen, as a part of the Public Sector Consultancy service offered by the Technical University of Denmark. The purpose of the report is to give the reader an insight into the stateof-the-art of formal methods. The reader...... is assumed to have some knowledge about software development, but not on formal methods. The background for the railway authorities’ interest in formal methods is the fact that during the next decade a total renewal of the Danish signalling infrastructure is going to take place. Central parts of the new...... systems will be software components that must fulfill strong safety requirements: in order to get the software certified at the highest Safety Integrity Levels of the European CENELEC standards for railway applications, the software providers are expected to use formal methods....

  9. Hybrid of Natural Element Method (NEM with Genetic Algorithm (GA to find critical slip surface

    Directory of Open Access Journals (Sweden)

    Shahriar Shahrokhabadi

    2014-06-01

    Full Text Available One of the most important issues in geotechnical engineering is the slope stability analysis for determination of the factor of safety and the probable slip surface. Finite Element Method (FEM is well suited for numerical study of advanced geotechnical problems. However, mesh requirements of FEM creates some difficulties for solution processing in certain problems. Recently, motivated by these limitations, several new Meshfree methods such as Natural Element Method (NEM have been used to analyze engineering problems. This paper presents advantages of using NEM in 2D slope stability analysis and Genetic Algorithm (GA optimization to determine the probable slip surface and the related factor of safety. The stress field is produced under plane strain condition using natural element formulation to simulate material behavior analysis utilized in conjunction with a conventional limit equilibrium method. In order to justify the preciseness and convergence of the proposed method, two kinds of examples, homogenous and non-homogenous, are conducted and results are compared with FEM and conventional limit equilibrium methods. The results show the robustness of the NEM in slope stability analysis.

  10. Crystal growth by Bridgman and Czochralski method of the ferromagnetic quantum critical material YbNi4P2

    Science.gov (United States)

    Kliemt, K.; Krellner, C.

    2016-09-01

    The tetragonal YbNi4P2 is one of the rare examples of compounds that allow the investigation of a ferromagnetic quantum critical point. We report in detail on two different methods which have been used to grow YbNi4P2 single crystals from a self-flux. The first, a modified Bridgman method, using a closed crucible system yields needle-shaped single crystals oriented along the [001]-direction. The second method, the Czochralski growth from a levitating melt, yields large single crystals which can be cut in any desired orientation. With this crucible-free method, samples without flux inclusions and a resistivity ratio at 1.8 K of RR1.8K = 17 have been grown.

  11. Application of bias factor method using random sampling technique for prediction accuracy improvement of critical eigenvalue of BWR

    International Nuclear Information System (INIS)

    Ito, Motohiro; Endo, Tomohiro; Yamamoto, Akio; Kuroda, Yusuke; Yoshii, Takashi

    2017-01-01

    The bias factor method based on the random sampling technique is applied to the benchmark problem of Peach Bottom Unit 2. Validity and availability of the present method, i.e. correction of calculation results and reduction of uncertainty, are confirmed in addition to features and performance of the present method. In the present study, core characteristics in cycle 3 are corrected with the proposed method using predicted and 'measured' critical eigenvalues in cycles 1 and 2. As the source of uncertainty, variance-covariance of cross sections is considered. The calculation results indicate that bias between predicted and measured results, and uncertainty owing to cross section can be reduced. Extension to other uncertainties such as thermal hydraulics properties will be a future task. (author)

  12. Statistical modeling methods to analyze the impacts of multiunit process variability on critical quality attributes of Chinese herbal medicine tablets.

    Science.gov (United States)

    Sun, Fei; Xu, Bing; Zhang, Yi; Dai, Shengyun; Yang, Chan; Cui, Xianglong; Shi, Xinyuan; Qiao, Yanjiang

    2016-01-01

    The quality of Chinese herbal medicine tablets suffers from batch-to-batch variability due to a lack of manufacturing process understanding. In this paper, the Panax notoginseng saponins (PNS) immediate release tablet was taken as the research subject. By defining the dissolution of five active pharmaceutical ingredients and the tablet tensile strength as critical quality attributes (CQAs), influences of both the manipulated process parameters introduced by an orthogonal experiment design and the intermediate granules' properties on the CQAs were fully investigated by different chemometric methods, such as the partial least squares, the orthogonal projection to latent structures, and the multiblock partial least squares (MBPLS). By analyzing the loadings plots and variable importance in the projection indexes, the granule particle sizes and the minimal punch tip separation distance in tableting were identified as critical process parameters. Additionally, the MBPLS model suggested that the lubrication time in the final blending was also important in predicting tablet quality attributes. From the calculated block importance in the projection indexes, the tableting unit was confirmed to be the critical process unit of the manufacturing line. The results demonstrated that the combinatorial use of different multivariate modeling methods could help in understanding the complex process relationships as a whole. The output of this study can then be used to define a control strategy to improve the quality of the PNS immediate release tablet.

  13. 临界水深计算方法的研究%Research on calculation method for critical water depth

    Institute of Scientific and Technical Information of China (English)

    王功

    2011-01-01

    总结了渠道临界水深常见的计算方法,分析了过水断面比能曲线的特性,根据渠道临界水深的定义,利用计算机软件编程技术可以解决大量繁琐计算的特点,求解了明渠临界水深,并且分析与总结了用定义法解决工程计算的意义.%Firstly, common calculation methods for the channel critical depth has been summarized, and the characteristics of specific energy curve of flow cross-section have been analyzed in this paper.By using computer software programming technology that can solve the massive trival calculation, based on the definition of the channel critical depth, the critical water depth was solved.And the significance of using the definition method to solve engineering calculation has been analysed and summarized.

  14. Statistical modeling methods to analyze the impacts of multiunit process variability on critical quality attributes of Chinese herbal medicine tablets

    Science.gov (United States)

    Sun, Fei; Xu, Bing; Zhang, Yi; Dai, Shengyun; Yang, Chan; Cui, Xianglong; Shi, Xinyuan; Qiao, Yanjiang

    2016-01-01

    The quality of Chinese herbal medicine tablets suffers from batch-to-batch variability due to a lack of manufacturing process understanding. In this paper, the Panax notoginseng saponins (PNS) immediate release tablet was taken as the research subject. By defining the dissolution of five active pharmaceutical ingredients and the tablet tensile strength as critical quality attributes (CQAs), influences of both the manipulated process parameters introduced by an orthogonal experiment design and the intermediate granules’ properties on the CQAs were fully investigated by different chemometric methods, such as the partial least squares, the orthogonal projection to latent structures, and the multiblock partial least squares (MBPLS). By analyzing the loadings plots and variable importance in the projection indexes, the granule particle sizes and the minimal punch tip separation distance in tableting were identified as critical process parameters. Additionally, the MBPLS model suggested that the lubrication time in the final blending was also important in predicting tablet quality attributes. From the calculated block importance in the projection indexes, the tableting unit was confirmed to be the critical process unit of the manufacturing line. The results demonstrated that the combinatorial use of different multivariate modeling methods could help in understanding the complex process relationships as a whole. The output of this study can then be used to define a control strategy to improve the quality of the PNS immediate release tablet. PMID:27932865

  15. A Novel Method of Evaluating Key Factors for Success in a Multifaceted Critical Care Fellowship Using Data Envelopment Analysis.

    Science.gov (United States)

    Tiwari, Vikram; Kumar, Avinash B

    2018-01-01

    The current system of summative multi-rater evaluations and standardized tests to determine readiness to graduate from critical care fellowships has limitations. We sought to pilot the use of data envelopment analysis (DEA) to assess what aspects of the fellowship program contribute the most to an individual fellow's success. DEA is a nonparametric, operations research technique that uses linear programming to determine the technical efficiency of an entity based on its relative usage of resources in producing the outcome. Retrospective cohort study. Critical care fellows (n = 15) in an Accreditation Council for Graduate Medical Education (ACGME) accredited fellowship at a major academic medical center in the United States. After obtaining institutional review board approval for this retrospective study, we analyzed the data of 15 anesthesiology critical care fellows from academic years 2013-2015. The input-oriented DEA model develops a composite score for each fellow based on multiple inputs and outputs. The inputs included the didactic sessions attended, the ratio of clinical duty works hours to the procedures performed (work intensity index), and the outputs were the Multidisciplinary Critical Care Knowledge Assessment Program (MCCKAP) score and summative evaluations of fellows. A DEA efficiency score that ranged from 0 to 1 was generated for each of the fellows. Five fellows were rated as DEA efficient, and 10 fellows were characterized in the DEA inefficient group. The model was able to forecast the level of effort needed for each inefficient fellow, to achieve similar outputs as their best performing peers. The model also identified the work intensity index as the key element that characterized the best performers in our fellowship. DEA is a feasible method of objectively evaluating peer performance in a critical care fellowship beyond summative evaluations alone and can potentially be a powerful tool to guide individual performance during the fellowship.

  16. Critical Thinking Skills to Literary Works: A Method of Teaching Language through Literature

    Directory of Open Access Journals (Sweden)

    Fithriyah Inda Nur Abida

    2016-05-01

    Full Text Available Teaching a language has become a challenging task for the teachers to train and to teach language for their students. In present time, the ability to master a language is vital for a language is a powerful means of  communicating. Most of us will not focus on the language present in the literature part because our mind sets only towards the grammar. This has made both the teacher and students to ignore the literature part and made them to focus only on grammatical part to learn language. The urge behind using literary works in the teaching a language is to argue that the current attempts to implant literary works to the teaching of a language definitely develop students’ critical thinking in such a way that help them to easily master a particular language. Learning literary works in a classroom not only make the students learn about a story but also study how the language are structured and how its structured bring a great difference in meaning. Through a literary works student sees the language of real-life contexts. They learn the feelings, ideas, and experiences of linguistics components that give a realistic touch and help them to learn a language in a comprehensive way. It is also found that using literary works in the teaching learning process can improve student’s ability both in micro-linguistics and macro-linguistics.

  17. A Method to Evaluate Critical Factors for Successful Implementation of Clinical Pathways.

    Science.gov (United States)

    Dong, W; Huang, Z

    2015-01-01

    Clinical pathways (CPs) have been viewed as a multidisciplinary tool to improve the quality and efficiency of evidence-based care. Despite widespread enthusiasm for CPs, research has shown that many CP initiatives are unsuccessful. To this end, this study provides a methodology to evaluate critical success factors (CSFs) that can aid healthcare organizations to achieve successful CP implementation. This study presents a new approach to evaluate CP implementation CSFs, with the aims being: (1) to identify CSFs for implementation of CPs through a comprehensive literature review and interviews with collaborative experts; (2) to use a filed study data with a robust fuzzy DEMATEL (the decision making trial and evaluation laboratory) approach to visualize the structure of complicated causal relationships between CSFs and obtain the influence level of these factors. The filed study data is provided by ten clinical experts of a Chinese hospital. 23 identified CSF factors which are initially identified through a review of the literature and interviews with collaborative experts. Then, a number of direct and indirect relationships are derived from the data such that different perceptions can be integrated into a compromised cause and effect model of CP implementation. The results indicate that the proposed approach can systematically evaluate CSFs and realize the importance of each factor such that the most common causes of failure of CP implementation could be eliminated or avoided. Therefore, the tool proposed would help healthcare organizations to manage CP implementation in a more effective and proactive way.

  18. Binomial Test Method for Determining Probability of Detection Capability for Fracture Critical Applications

    Science.gov (United States)

    Generazio, Edward R.

    2011-01-01

    The capability of an inspection system is established by applications of various methodologies to determine the probability of detection (POD). One accepted metric of an adequate inspection system is that for a minimum flaw size and all greater flaw sizes, there is 0.90 probability of detection with 95% confidence (90/95 POD). Directed design of experiments for probability of detection (DOEPOD) has been developed to provide an efficient and accurate methodology that yields estimates of POD and confidence bounds for both Hit-Miss or signal amplitude testing, where signal amplitudes are reduced to Hit-Miss by using a signal threshold Directed DOEPOD uses a nonparametric approach for the analysis or inspection data that does require any assumptions about the particular functional form of a POD function. The DOEPOD procedure identifies, for a given sample set whether or not the minimum requirement of 0.90 probability of detection with 95% confidence is demonstrated for a minimum flaw size and for all greater flaw sizes (90/95 POD). The DOEPOD procedures are sequentially executed in order to minimize the number of samples needed to demonstrate that there is a 90/95 POD lower confidence bound at a given flaw size and that the POD is monotonic for flaw sizes exceeding that 90/95 POD flaw size. The conservativeness of the DOEPOD methodology results is discussed. Validated guidelines for binomial estimation of POD for fracture critical inspection are established.

  19. Critical heat flux acoustic detection: Methods and application to ITER divertor vertical target monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Courtois, X., E-mail: xavier.courtois@cea.fr [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Escourbiac, F. [ITER Organization, Route de Vinon sur Verdon, F-13115 Saint-Paul-Lez-Durance (France); Richou, M.; Cantone, V. [CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Constans, S. [AREVA-NP, Le Creusot (France)

    2013-10-15

    Actively cooled plasma facing components (PFCs) have to exhaust high heat fluxes from plasma radiation and plasma–wall interaction. Critical heat flux (CHF) event may occur in the cooling channel due to unexpected heat loading or operational conditions, and has to be detected as soon as possible. Therefore it is essential to develop means of monitoring based on precursory signals providing an early detection of this destructive phenomenon, in order to be able to stop operation before irremediable damages appear. Capabilities of CHF early detection based on acoustic techniques on PFC mock-ups cooled by pressurised water were already demonstrated. This paper addresses the problem of the detection in case of flow rate reduction and of flow dilution resulting from multiple plasma facing units (PFU) which are hydraulically connected in parallel, which is the case of ITER divertor. An experimental study is launched on a dedicated mock-up submitted to heat loads up to the CHF. It shows that the measurement of the acoustic waves, generated by the cooling phenomena, allows the CHF detection in conditions similar to that of the ITER divertor, with a reasonable number of sensors. The paper describes the mock-ups and the tests sequences, and comments the results.

  20. Beyond statistical methods: teaching critical thinking to first-year university students

    Science.gov (United States)

    David, Irene; Brown, Jennifer Ann

    2012-12-01

    We discuss a major change in the way we teach our first-year statistics course. We have redesigned this course with emphasis on teaching critical thinking. We recognized that most of the students take the course for general knowledge and support of other majors, and very few are planning to major in statistics. We identified the essential aspects of a first-year statistics course, given this student mix, focusing on a simple question, 'Given this is the last chance you have to teach statistics, what are the essential skills students need?' We have moved from thinking about statistics skills needed for a statistician to skills needed to participate in today's society. We have changed the way we deliver the course with less emphasis on lectures and more on alternative resources including on-line tutorials, Excel, computer-based skills testing, web-based learning materials and smaller group activities such as study groups and example classes. Feedback from students shows that they are very receptive and enthusiastic.

  1. Domain decomposition methods for the mixed dual formulation of the critical neutron diffusion problem

    International Nuclear Information System (INIS)

    Guerin, P.

    2007-12-01

    The neutronic simulation of a nuclear reactor core is performed using the neutron transport equation, and leads to an eigenvalue problem in the steady-state case. Among the deterministic resolution methods, diffusion approximation is often used. For this problem, the MINOS solver based on a mixed dual finite element method has shown his efficiency. In order to take advantage of parallel computers, and to reduce the computing time and the local memory requirement, we propose in this dissertation two domain decomposition methods for the resolution of the mixed dual form of the eigenvalue neutron diffusion problem. The first approach is a component mode synthesis method on overlapping sub-domains. Several Eigenmodes solutions of a local problem solved by MINOS on each sub-domain are taken as basis functions used for the resolution of the global problem on the whole domain. The second approach is a modified iterative Schwarz algorithm based on non-overlapping domain decomposition with Robin interface conditions. At each iteration, the problem is solved on each sub domain by MINOS with the interface conditions deduced from the solutions on the adjacent sub-domains at the previous iteration. The iterations allow the simultaneous convergence of the domain decomposition and the eigenvalue problem. We demonstrate the accuracy and the efficiency in parallel of these two methods with numerical results for the diffusion model on realistic 2- and 3-dimensional cores. (author)

  2. Critical assessment of three high performance liquid chromatography analytical methods for food carotenoid quantification.

    Science.gov (United States)

    Dias, M Graça; Oliveira, Luísa; Camões, M Filomena G F C; Nunes, Baltazar; Versloot, Pieter; Hulshof, Paul J M

    2010-05-21

    Three sets of extraction/saponification/HPLC conditions for food carotenoid quantification were technically and economically compared. Samples were analysed for carotenoids alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein, lycopene, and zeaxanthin. All methods demonstrated good performance in the analysis of a composite food standard reference material for the analytes they are applicable to. Methods using two serial connected C(18) columns and a mobile phase based on acetonitrile, achieved a better carotenoid separation than the method using a mobile phase based on methanol and one C(18)-column. Carotenoids from leafy green vegetable matrices appeared to be better extracted with a mixture of methanol and tetrahydrofuran than with tetrahydrofuran alone. Costs of carotenoid determination in foods were lower for the method with mobile phase based on methanol. However for some food matrices and in the case of E-Z isomer separations, this was not technically satisfactory. Food extraction with methanol and tetrahydrofuran with direct evaporation of these solvents, and saponification (when needed) using pyrogallol as antioxidant, combined with a HPLC system using a slight gradient mobile phase based on acetonitrile and a stationary phase composed by two serial connected C(18) columns was the most technically and economically favourable method. 2010. Published by Elsevier B.V.

  3. Critical analysis of the images methods in detection and diagnosis in breast cancer

    International Nuclear Information System (INIS)

    Mendonca, Maria H.S.

    1995-01-01

    The female breast cancer is a relevant health issue among female population, due its incidence and remarkable effects in the biological, psychological and social levels. Its early diagnosis is important because it allows more effective treatments and enhances changes of cure, even allowing conservative surgical procedures. To make this possible it is essential the periodic breast imaging exams. The available imaging methods to date are: mammography, ultrasonography, thermography, nuclear medicine, computed tomography and MRI. All these methods have their advantages and disadvantages, applications and limitations and some are even in experimental stages. These methods must exercised in association to become more effective. Mammography is still, beyond and doubt the elected breast exam. even though imperfect. It must be performed repeatedly at periodic intervals depending upon the intrinsic conditions of the patient. The other methods complement the mammographic findings, clearing some of them. In this paper, the imaging methods available in our environmental for detected diagnosis of the early breast cancer are analyzed with emphasis in mammography and ultrasonography. Their advantages, disadvantages, indications and limitations are discussed. (author)

  4. Modeling of the Critical Micelle Concentration (CMC) of Nonionic Surfactants with an Extended Group-Contribution Method

    DEFF Research Database (Denmark)

    Mattei, Michele; Kontogeorgis, Georgios; Gani, Rafiqul

    2013-01-01

    , those compounds that exhibit larger correlation errors (based only on first- and second-order groups) are assigned to more detailed molecular descriptions, so that better correlations of critical micelle concentrations are obtained. The group parameter estimation has been performed using a data set......A group-contribution (GC) property prediction model for estimating the critical micelle concentration (CMC) of nonionic surfactants in water at 25 °C is presented. The model is based on the Marrero and Gani GC method. A systematic analysis of the model performance against experimental data...... concentration, and in particular, the quantitative structure−property relationship models, the developed GC model provides an accurate correlation and allows for an easier and faster application in computer-aided molecular design techniques facilitating chemical process and product design....

  5. A Method of Calculating Critical Depth of Burial of Explosive Charges to Generate Bulging and Cratering in Rock

    Directory of Open Access Journals (Sweden)

    Mingyang Wang

    2016-01-01

    Full Text Available For underground explosions, a thin to medium thickness layer near the cavity of an explosion can be considered a theoretical shell structure. Detonation products transmit the effective energy of explosives to this shell which can expand thus leading to irreversible deformation of the surrounding medium. Based on mass conservation, incompressible conditions, and boundary conditions, the possible kinematic velocity fields in the plastic zone are established. Based on limit equilibrium theory, this work built equations of material resistance corresponding to different possible kinematic velocity fields. Combined with initial conditions and boundary conditions, equations of motion and material resistance are solved, respectively. It is found that critical depth of burial is positively related to a dimensionless impact factor, which reflects the characteristics of the explosives and the surrounding medium. Finally, an example is given, which suggests that this method is capable of calculating the critical depth of burial and the calculated results are consistent with empirical results.

  6. Criticality Model

    International Nuclear Information System (INIS)

    Alsaed, A.

    2004-01-01

    The ''Disposal Criticality Analysis Methodology Topical Report'' (YMP 2003) presents the methodology for evaluating potential criticality situations in the monitored geologic repository. As stated in the referenced Topical Report, the detailed methodology for performing the disposal criticality analyses will be documented in model reports. Many of the models developed in support of the Topical Report differ from the definition of models as given in the Office of Civilian Radioactive Waste Management procedure AP-SIII.10Q, ''Models'', in that they are procedural, rather than mathematical. These model reports document the detailed methodology necessary to implement the approach presented in the Disposal Criticality Analysis Methodology Topical Report and provide calculations utilizing the methodology. Thus, the governing procedure for this type of report is AP-3.12Q, ''Design Calculations and Analyses''. The ''Criticality Model'' is of this latter type, providing a process evaluating the criticality potential of in-package and external configurations. The purpose of this analysis is to layout the process for calculating the criticality potential for various in-package and external configurations and to calculate lower-bound tolerance limit (LBTL) values and determine range of applicability (ROA) parameters. The LBTL calculations and the ROA determinations are performed using selected benchmark experiments that are applicable to various waste forms and various in-package and external configurations. The waste forms considered in this calculation are pressurized water reactor (PWR), boiling water reactor (BWR), Fast Flux Test Facility (FFTF), Training Research Isotope General Atomic (TRIGA), Enrico Fermi, Shippingport pressurized water reactor, Shippingport light water breeder reactor (LWBR), N-Reactor, Melt and Dilute, and Fort Saint Vrain Reactor spent nuclear fuel (SNF). The scope of this analysis is to document the criticality computational method. The criticality

  7. Study on the method of determining the sub-criticality of a reactor via the measurement of core neutron flux spatial distribution

    International Nuclear Information System (INIS)

    Ma Aifeng; Jiang Xiaofeng; Zhang Shaohong

    2007-01-01

    A new methodology based on rigorous reactor physics theory astead of the point reactor assumption was proposed to determine or monitor the sub-criticality ora reactor, especially the sub-critical reactor of ADS, via the measurement of in-core flux spatial distribution. Preliminary numerical studies on the 1st ADS sub-critical experimental facilities-Venus No.1 in China have demonstrated the feasibility of this new method. Related discussions pointed out the potential applications of the method. (authors)

  8. How Assessment Methods Can Support Solid Waste Management in Developing Countries—A Critical Review

    Directory of Open Access Journals (Sweden)

    Christian Zurbrügg

    2014-01-01

    Full Text Available Selecting actions for improvement of solid waste management in low and middle income countries and understanding how a specific decision choice will fit and impact on a local context is key to identifying sustainable solutions. Assessment of the choice (be it technical or managerial and assessment of the local enabling or disabling conditions are both important steps in the decision making process. Various assessment tools and methods are currently available to support decision-making in solid waste management. Assessment can be used to identify weaknesses or strengths of existing systems in a structured way and hereby highlight factors of success and failure. Assessment methods can also evaluate and compare different possible choices as in project scenarios. This overview describes established and innovative assessment methods serving both these purposes. A range of assessment tools are often designed to assess a specific sustainability domain (technical, environmental and health, economic and financial, social and institutional, organizational aspects, others attempt to provide a more holistic picture by integrating different sustainability domains into the same tool. This paper reviews a number of methods describing and discussing each of them, and referring to their use in low and middle-income countries if published in scientific literature. The overview concludes that in low- and middle-income countries the use of comprehensive assessment methods is yet very limited. We hypothesize that most formal methods of assessment are still too complex and generally overburden the weak local capacities intended for their usage. The few applications identified, were conducted by academia for scientific purposes. Lack of resources to collect the vast data required for some assessment methods is a further restriction to their practical application. Future development is suggested to improve user friendliness of existing tools or to simplify certain

  9. A method of sub-critical experimentation, 'the neutrostat'; Une methode d'experimentation sous critique 'le neutrostat'

    Energy Technology Data Exchange (ETDEWEB)

    Martelly, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The method proposed is designed for the study of neutronic properties of a sample (its material buckling, for example) and consists in submitting the sample to uniform surface density irradiation, its surface being a sphere or a cylinder which is supposed, temporarily, to be infinite. Neutron density in the sample will thus be uniform if its laplacian is nil: any curve in the distribution clearly indicating its absorbent or multiplying properties. In the case of a sample with multiplying power, density is identical to that in an active core, thus measurement of buckling will be free from considerable systematic error causes. The thermic equivalent of this type of irradiation would be a thermostat with an external heat source distributed uniformly over its surface: its temperature would be uniform. It is this analogy that has led us to baptize it the 'Neutrostat'. (author)Fren. [French] En vue d'etudier les proprietes neutroniques d'un milieu (son laplacien 'matiere' par exemple), la methode proposee consiste a le soumettre a des conditions d'irradiation uniforme sur sa surface, celle-ci ayant la forme d'une sphere ou d'un cylindre que nous supposons provisoirement infini. Les neutrons s'y trouvent alors repartis avec une densite uniforme si le milieu est un diffuseur pur. Toute courbure de cette repartition sera un indice sensible de ses proprietes absorbantes ou multiplicatrices. Dans le cas d'un milieu multiplicateur, la repartition est identique a celle qui regne au milieu d'une pile critique et nous verrons que la mesure du laplacien est alors exempte de causes d'erreurs systematiques importantes. L'equivalent thermique d'un tel mode d'irradiation serait un dispositif thermostatique dont la source de chaleur externe serait repartie uniformement sur la surface: il y regnerait une temperature uniforme. C'est cette analogie qui nous a guides dans le choix du vocable propose dans le titre: 'Neutrostat'. (auteur)

  10. Diagnostic Methods of Helicobacter pylori Infection for Epidemiological Studies: Critical Importance of Indirect Test Validation.

    Science.gov (United States)

    Miftahussurur, Muhammad; Yamaoka, Yoshio

    2016-01-01

    Among the methods developed to detect H. pylori infection, determining the gold standard remains debatable, especially for epidemiological studies. Due to the decreasing sensitivity of direct diagnostic tests (histopathology and/or immunohistochemistry [IHC], rapid urease test [RUT], and culture), several indirect tests, including antibody-based tests (serology and urine test), urea breath test (UBT), and stool antigen test (SAT) have been developed to diagnose H. pylori infection. Among the indirect tests, UBT and SAT became the best methods to determine active infection. While antibody-based tests, especially serology, are widely available and relatively sensitive, their specificity is low. Guidelines indicated that no single test can be considered as the gold standard for the diagnosis of H. pylori infection and that one should consider the method's advantages and disadvantages. Based on four epidemiological studies, culture and RUT present a sensitivity of 74.2-90.8% and 83.3-86.9% and a specificity of 97.7-98.8% and 95.1-97.2%, respectively, when using IHC as a gold standard. The sensitivity of serology is quite high, but that of the urine test was lower compared with that of the other methods. Thus, indirect test validation is important although some commercial kits propose universal cut-off values.

  11. A simple method to measure critical angles for high-sensitivity differential refractometry.

    Science.gov (United States)

    Zilio, S C

    2012-01-16

    A total internal reflection-based differencial refractometer, capable of measuring the real and imaginary parts of the complex refractive index in real time, is presented. The device takes advantage of the phase difference acquired by s- and p-polarized light to generate an easily detectable minimum at the reflected profile. The method allows to sensitively measuring transparent and turbid liquid samples.

  12. Critical assessment of three high performance liquid chromatography analytical methods for food carotenoid quantification

    NARCIS (Netherlands)

    Dias, M.G.; Oliveira, L.; Camoes, M.F.G.F.C.; Nunes, B.; Versloot, P.; Hulshof, P.J.M.

    2010-01-01

    Three sets of extraction/saponification/HPLC conditions for food carotenoid quantification were technically and economically compared. Samples were analysed for carotenoids a-carotene, ß-carotene, ß-cryptoxanthin, lutein, lycopene, and zeaxanthin. All methods demonstrated good performance in the

  13. Criticism on Jäntti's Three Point Method on curtailing gas adsorption measurements

    NARCIS (Netherlands)

    Massen, C.H.; Poulis, J.A.; Robens, E.

    2000-01-01

    Jäntti introduced a method to reduce the time required for the stepwise measurement of adsorption isotherms (Jäntti et al., Progress in Vacuum Microbalance Techniques, Vol. 1, Heyden, London, pp. 345–353, 1972). After a pressure change he measured the adsorbed mass three times and calculated its

  14. Critical factors in the empirical performance of temporal difference and evolutionary methods for reinforcement learning

    NARCIS (Netherlands)

    Whiteson, S.; Taylor, M.E.; Stone, P.

    2010-01-01

    Temporal difference and evolutionary methods are two of the most common approaches to solving reinforcement learning problems. However, there is little consensus on their relative merits and there have been few empirical studies that directly compare their performance. This article aims to address

  15. Methods for Practising Ethics in Research and Innovation : A Literature Review, Critical Analysis and Recommendations

    NARCIS (Netherlands)

    Reijers, Wessel; Wright, David; Brey, Philip; Weber, Karsten; Rodrigues, Rowena; O’Sullivan, Declan; Gordijn, Bert

    2017-01-01

    This paper provides a systematic literature review, analysis and discussion of methods that are proposed to practise ethics in research and innovation (R&I). Ethical considerations concerning the impacts of R&I are increasingly important, due to the quickening pace of technological innovation and

  16. Creating Critical Conversations: Investigating the Utility of Socratic Dialogues in Elementary Social Studies Methods

    Science.gov (United States)

    Buchanan, Lisa Brown

    2012-01-01

    This article explores the utility of Socratic dialogues in the elementary social studies methods course. Findings include preservice teachers' behaviors during dialogues, perceived strengths and challenges of using Socratic dialogues in teacher education, and the impact on student learning. Challenges and apprehensions encountered by the teacher…

  17. A critical analysis of methods for rapid and nondestructive determination of wood density in standing trees

    Science.gov (United States)

    Shan Gao; Xiping Wang; Michael C. Wiemann; Brian K. Brashaw; Robert J. Ross; Lihai Wang

    2017-01-01

    Key message Field methods for rapid determination of wood density in trees have evolved from increment borer, torsiometer, Pilodyn, and nail withdrawal into sophisticated electronic tools of resistance drilling measurement. A partial resistance drilling approach coupled with knowledge of internal tree density distribution may...

  18. Critical Test of Some Computational Chemistry Methods for Prediction of Gas-Phase Acidities and Basicities.

    Science.gov (United States)

    Toomsalu, Eve; Koppel, Ilmar A; Burk, Peeter

    2013-09-10

    Gas-phase acidities and basicities were calculated for 64 neutral bases (covering the scale from 139.9 kcal/mol to 251.9 kcal/mol) and 53 neutral acids (covering the scale from 299.5 kcal/mol to 411.7 kcal/mol). The following methods were used: AM1, PM3, PM6, PDDG, G2, G2MP2, G3, G3MP2, G4, G4MP2, CBS-QB3, B1B95, B2PLYP, B2PLYPD, B3LYP, B3PW91, B97D, B98, BLYP, BMK, BP86, CAM-B3LYP, HSEh1PBE, M06, M062X, M06HF, M06L, mPW2PLYP, mPW2PLYPD, O3LYP, OLYP, PBE1PBE, PBEPBE, tHCTHhyb, TPSSh, VSXC, X3LYP. The addition of the Grimmes empirical dispersion correction (D) to B2PLYP and mPW2PLYP was evaluated, and it was found that adding this correction gave more-accurate results when considering acidities. Calculations with B3LYP, B97D, BLYP, B2PLYPD, and PBE1PBE methods were carried out with five basis sets (6-311G**, 6-311+G**, TZVP, cc-pVTZ, and aug-cc-pVTZ) to evaluate the effect of basis sets on the accuracy of calculations. It was found that the best basis sets when considering accuracy of results and needed time were 6-311+G** and TZVP. Among semiempirical methods AM1 had the best ability to reproduce experimental acidities and basicities (the mean absolute error (mae) was 7.3 kcal/mol). Among DFT methods the best method considering accuracy, robustness, and computation time was PBE1PBE/6-311+G** (mae = 2.7 kcal/mol). Four Gaussian-type methods (G2, G2MP2, G4, and G4MP2) gave similar results to each other (mae = 2.3 kcal/mol). Gaussian-type methods are quite accurate, but their downside is the relatively long computational time.

  19. Critical review and hydrologic application of threshold detection methods for the generalized Pareto (GP) distribution

    Science.gov (United States)

    Mamalakis, Antonios; Langousis, Andreas; Deidda, Roberto

    2016-04-01

    Estimation of extreme rainfall from data constitutes one of the most important issues in statistical hydrology, as it is associated with the design of hydraulic structures and flood water management. To that extent, based on asymptotic arguments from Extreme Excess (EE) theory, several studies have focused on developing new, or improving existing methods to fit a generalized Pareto (GP) distribution model to rainfall excesses above a properly selected threshold u. The latter is generally determined using various approaches, such as non-parametric methods that are intended to locate the changing point between extreme and non-extreme regions of the data, graphical methods where one studies the dependence of GP distribution parameters (or related metrics) on the threshold level u, and Goodness of Fit (GoF) metrics that, for a certain level of significance, locate the lowest threshold u that a GP distribution model is applicable. In this work, we review representative methods for GP threshold detection, discuss fundamental differences in their theoretical bases, and apply them to 1714 daily rainfall records from the NOAA-NCDC open-access database, with more than 110 years of data. We find that non-parametric methods that are intended to locate the changing point between extreme and non-extreme regions of the data are generally not reliable, while methods that are based on asymptotic properties of the upper distribution tail lead to unrealistically high threshold and shape parameter estimates. The latter is justified by theoretical arguments, and it is especially the case in rainfall applications, where the shape parameter of the GP distribution is low; i.e. on the order of 0.1 ÷ 0.2. Better performance is demonstrated by graphical methods and GoF metrics that rely on pre-asymptotic properties of the GP distribution. For daily rainfall, we find that GP threshold estimates range between 2÷12 mm/d with a mean value of 6.5 mm/d, while the existence of quantization in the

  20. A critical review of accounting and economic methods for estimating the costs of addiction treatment.

    Science.gov (United States)

    Cartwright, William S

    2008-04-01

    Researchers have been at the forefront of applying new costing methods to drug abuse treatment programs and innovations. The motivation for such work has been to improve costing accuracy. Recent work has seen applications initiated in establishing charts of account and cost accounting for service delivery. As a result, researchers now have available five methods to apply to the costing of drug abuse treatment programs. In all areas of costing, there is room for more research on costing concepts and measurement applications. Additional work would be useful in establishing studies with activity-based costing for both research and managerial purposes. Studies of economies of scope are particularly relevant because of the integration of social services and criminal justice in drug abuse treatment. In the long run, managerial initiatives to improve the administration and quality of drug abuse treatment will benefit directly from research with new information on costing techniques.

  1. Identifying critical constraints for the maximum loadability of electric power systems - analysis via interior point method

    Energy Technology Data Exchange (ETDEWEB)

    Barboza, Luciano Vitoria [Sul-riograndense Federal Institute for Education, Science and Technology (IFSul), Pelotas, RS (Brazil)], E-mail: luciano@pelotas.ifsul.edu.br

    2009-07-01

    This paper presents an overview about the maximum load ability problem and aims to study the main factors that limit this load ability. Specifically this study focuses its attention on determining which electric system buses influence directly on the power demand supply. The proposed approach uses the conventional maximum load ability method modelled by an optimization problem. The solution of this model is performed using the Interior Point methodology. As consequence of this solution method, the Lagrange multipliers are used as parameters that identify the probable 'bottlenecks' in the electric power system. The study also shows the relationship between the Lagrange multipliers and the cost function in the Interior Point optimization interpreted like sensitivity parameters. In order to illustrate the proposed methodology, the approach was applied to an IEEE test system and to assess its performance, a real equivalent electric system from the South- Southeast region of Brazil was simulated. (author)

  2. Analytical Methods for the Determination of Rosuvastatin in Pharmaceutical Formulations and Biological Fluids: A Critical Review.

    Science.gov (United States)

    Ângelo, Marilene Lopes; Moreira, Fernanda de Lima; Morais Ruela, André Luís; Santos, Ana Laura Araújo; Salgado, Hérida Regina Nunes; de Araújo, Magali Benjamim

    2018-07-04

    Rosuvastatin calcium (ROS), ( Figure 1 ) belongs to the "statins" group, which is the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor. This drug is indicated for dyslipidemias treatment and can help to decrease the level of "bad cholesterol" and can consequently reduce the development of atherosclerosis and the risk of heart diseases. ROS was developed by Astra-Zeneca and it was approved in 2003 by the FDA in the United States. In 2015, under the trade name Crestor®, it was the fourth largest selling drug in the United States with sales above $5 billion. This study presents a literature review of analytical methods for the quantification of ROS in pharmaceutical preparations and biological fluids. The major analytical methods described in this study for ROS were spectrophotometry, high-performance liquid chromatography (HPLC) coupled to ultraviolet (UV) detection, and tandem mass spectrometry (LC-MS/MS).

  3. The comparison of MCNP perturbation technique with MCNP difference method in critical calculation

    International Nuclear Information System (INIS)

    Liu Bin; Lv Xuefeng; Zhao Wei; Wang Kai; Tu Jing; Ouyang Xiaoping

    2010-01-01

    For a nuclear fission system, we calculated Δk eff , which arise from system material composition changes, by two different approaches, the MCNP perturbation technique and the MCNP difference method. For every material composition change, we made four different runs, each run with different cycles or each cycle generating different neutrons, then we compared the two Δk eff that are obtained by two different approaches. As a material composition change in any particular cell of the nuclear fission system is small compared to the material compositions in the whole nuclear fission system, in other words, this composition change can be treated as a small perturbation, the Δk eff results obtained from the MCNP perturbation technique are much quicker, much more efficient and reliable than the results from the MCNP difference method. When a material composition change in any particular cell of the nuclear fission system is significant compared to the material compositions in the whole nuclear fission system, both the MCNP perturbation technique and the MCNP difference method can give satisfactory results. But for the run with the same cycles and each cycle generating the same neutrons, the results obtained from the MCNP perturbation technique are systemically less than the results obtained from the MCNP difference method. To further confirm our calculation results from the MCNP4C, we run the exact same MCNP4C input file in MCNP5, the calculation results from MCNP5 are the same as the calculation results from MCNP4C. We need caution when using the MCNP perturbation technique to calculate the Δk eff as the material composition change is large compared to the material compositions in the whole nuclear fission system, even though the material composition changes of any particular cell of the fission system still meet the criteria of MCNP perturbation technique.

  4. Some Critical Points in the Methods and Philosphy of Physical Sciences

    OpenAIRE

    Bozdemir, Süleyman

    2018-01-01

    Nowadays, it seems that there are not enough studies on the philosophy and methods of physical sciences that would be attractive to the researchers in the field. However, many revolutionary inventions have come from the mechanism of the philosophical thought of the physical sciences. This is, of course, a vast and very interesting topic that must be investigated in detail by philosophers, scientists or philosopher-scientists such as physicists. In order to do justice to it one has to write a ...

  5. HISTORICISM AND HISTORICAL AND CRITICAL METHOD IN WOLFHART PANNENBERG’S THEOLOGY

    Directory of Open Access Journals (Sweden)

    Andrey Lavrentyev

    2012-06-01

    Full Text Available Researched is the problem of awareness of historicism for the christian theology, presented in the works of a german theologian Wolfhart Pannenberg. Discussed are the issue of application of the methods of historical science in theology, the problem of historical anthropocentrism, coexistence «natural» and «supernatural» events in history, teleology and contingency of history. It is come to conclusion of special significance of historical knowledge for Christian theology

  6. Critical path method as the criterion for optimization of business planning process

    OpenAIRE

    Butsenko Elena V.

    2016-01-01

    In today's economy the task of improving business planning is considered a necessary component of any enterprise management process and is precisely the solution drawn from that task which determines the financial policy and economic structure. The development of technologies based on the optimization of business planning is a very urgent scientific challenge. In this paper we propose to use the methods of network planning and management as a tool for economic and mathematical modeling to...

  7. A method for quantitative nondestructive evaluation using high critical temperature superconducting quantum interference device

    International Nuclear Information System (INIS)

    Kojima, Fumio; Nagashima, Yoshinori; Suzuki, Daisuke; Kasai, Naoko

    1998-01-01

    This paper is concerned with a computational method for detecting and characterizing defect shapes in conducting materials using superconducting quantum interference device (SQUID). The mathematical model is described by electrical potential problems with mixed boundary condition. The model output is then represented by Biot-Savart's law. The estimation scheme is proposed for reconstructing defect shapes in sample materials with defect. Successful numerical results are reported in order to show the feasibility of the proposed algorithms. (author)

  8. A method for quantitative nondestructive evaluation using high critical temperature superconducting quantum interference device

    Energy Technology Data Exchange (ETDEWEB)

    Kojima, Fumio; Nagashima, Yoshinori [Osaka Inst. of Tech. (Japan); Suzuki, Daisuke; Kasai, Naoko

    1998-06-01

    This paper is concerned with a computational method for detecting and characterizing defect shapes in conducting materials using superconducting quantum interference device (SQUID). The mathematical model is described by electrical potential problems with mixed boundary condition. The model output is then represented by Biot-Savart`s law. The estimation scheme is proposed for reconstructing defect shapes in sample materials with defect. Successful numerical results are reported in order to show the feasibility of the proposed algorithms. (author)

  9. Optimising the Design Process of the Injection Camshaft by Critical Path Method (CPM

    Directory of Open Access Journals (Sweden)

    Olga-Ioana Amariei

    2016-10-01

    Full Text Available In the present paper a series of advantages of the CPM method are presented, focusing on the optimization of design duration of an injection camshaft, by cost criteria. The minimum duration of finalizing the design of the injection camshaft will be determined, as well as the total cost associated to this project, normally, and then under crash regime. At the end, two types of sensitivity analysis will be performed: Meeting the desire completation time and Meeting the desired budget cost

  10. Study by the disco method of critical components of a P.W.R. normal feedwater system

    International Nuclear Information System (INIS)

    Duchemin, B.; Villeneuve, M.J. de; Vallette, F.; Bruna, J.G.

    1983-03-01

    The DISCO (Determination of Importance Sensitivity of COmponents) method objectif is to rank the components of a system in order to obtain the most important ones versus availability. This method uses the fault tree description of the system and the cut set technique. It ranks the components by ordering the importances attributed to each one. The DISCO method was applied to the study of the 900 MWe P.W.R. normal feedwater system with insufficient flow in steam generator. In order to take account of operating experience several data banks were used and the results compared. This study allowed to determine the most critical component (the turbo-pumps) and to propose and quantify modifications of the system in order to improve its availability

  11. Method of evaluating the impact of ERP implementation critical success factors - a case study in oil and gas industries

    Science.gov (United States)

    Gajic, Gordana; Stankovski, Stevan; Ostojic, Gordana; Tesic, Zdravko; Miladinovic, Ljubomir

    2014-01-01

    The so far implemented enterprise resource planning (ERP) systems have in many cases failed to meet the requirements regarding the business process control, decrease of business costs and increase of company profit margin. Therefore, there is a real need for an evaluation of the influence of ERP on the company's performance indicators. Proposed in this article is an advanced model for the evaluation of the success of ERP implementation on organisational and operational performance indicators in oil-gas companies. The recommended method establishes a correlation between a process-based method, a scorecard model and ERP critical success factors. The method was verified and tested on two case studies in oil-gas companies using the following procedure: the model was developed, tested and implemented in a pilot gas-oil company, while the results were implemented and verified in another gas-oil company.

  12. A critical assessment of theoretical methods for finding reaction pathways and transition states of surface processes

    International Nuclear Information System (INIS)

    Klimes, JirI; Michaelides, Angelos; Bowler, David R

    2010-01-01

    The performance of a variety of techniques for locating transition states on potential energy surfaces is evaluated within the density functional theory framework. Diffusion of a water molecule across NaCl(001) and HCl bond breaking on the same surface are treated as general test cases; the former is an example of a low barrier diffusion process and the latter an example of a relatively high barrier covalent bond rupture event. The methods considered include the nudged elastic band (NEB), Dewar, Healy and Stewart (DHS), dimer, constrained optimization (CO), activation-relaxation technique (ART) and one-side growing string (OGS) as well as novel combinations of the DHS with growing string (DHS + GS) and DHS plus climbing image (CI-DHS). A key conclusion to come from this study is that the NEB method is relatively fast, especially when just a single (climbing) image is used. Indeed, using more images represents an unnecessary computational burden for our set of processes. The dimer method exhibits variable performance; being poor for the water diffusion processes, which have small activation energies, but much more efficient for the HCl bond breaking process which has a higher barrier. When only a poor initial guess of the transition state geometry is available, the CI-DHS scheme is one of the most efficient techniques considered. And as a means to quickly establish an approximate minimum energy pathway the DHS + GS scheme offers some potential.

  13. Application of the critical pathway and integrated case teaching method to nursing orientation.

    Science.gov (United States)

    Goodman, D

    1997-01-01

    Nursing staff development programs must be responsive to current changes in healthcare. New nursing staff must be prepared to manage continuous change and to function competently in clinical practice. The orientation pathway, based on a case management model, is used as a structure for the orientation phase of staff development. The integrated case is incorporated as a teaching strategy in orientation. The integrated case method is based on discussion and analysis of patient situations with emphasis on role modeling and integration of theory and skill. The orientation pathway and integrated case teaching method provide a useful framework for orientation of new staff. Educators, preceptors and orientees find the structure provided by the orientation pathway very useful. Orientation that is developed, implemented and evaluated based on a case management model with the use of an orientation pathway and incorporation of an integrated case teaching method provides a standardized structure for orientation of new staff. This approach is designed for the adult learner, promotes conceptual reasoning, and encourages the social and contextual basis for continued learning.

  14. Methods of measurement of myocardial blood flow in patients: a critical review

    International Nuclear Information System (INIS)

    Marcus, M.L.; Wilson, R.F.; White, C.W.

    1987-01-01

    During the past decade, major progress has been made in the evolution of technology directed toward the accurate measurement of regional myocardial perfusion in patients. The deficiencies of some of the older methods (thermodilution and gas clearance) are better appreciated and improved approaches (Doppler catheters, positron-emission tomography, and digital subtraction angiography) have been developed. The new approaches should play a major role in research and for most applications the older methods will gradually be replaced. Efforts to bring these new methods to community hospitals and practicing cardiologists should be stimulated. Doppler catheters, positron-emission tomography, and digital-subtraction angiography are commercially available and Doppler catheters and digital-subtraction angiography could be easily incorporated into routine cardiac catheterization procedures. The Doppler catheter is the most inexpensive and probably the simplest to apply. In our opinion, routine measurements of coronary flow reserve will significantly improve the care of patients with coronary obstructive disease and other diseases that impair myocardial perfusion. If coronary reserve measurements are used frequently, patient selection for coronary angioplasty and bypass surgery will no longer depend entirely on visual assessment of percent diameter stenosis, a very poor criterion in many situations. Also, patients with chest pain syndromes, normal coronary vessels, and impaired coronary reserve will be identified and perhaps some effective treatment for this condition will be devised. 77 references

  15. Hybrid MCDA Methods to Integrate Multiple Ecosystem Services in Forest Management Planning: A Critical Review.

    Science.gov (United States)

    Uhde, Britta; Hahn, W Andreas; Griess, Verena C; Knoke, Thomas

    2015-08-01

    Multi-criteria decision analysis (MCDA) is a decision aid frequently used in the field of forest management planning. It includes the evaluation of multiple criteria such as the production of timber and non-timber forest products and tangible as well as intangible values of ecosystem services (ES). Hence, it is beneficial compared to those methods that take a purely financial perspective. Accordingly, MCDA methods are increasingly popular in the wide field of sustainability assessment. Hybrid approaches allow aggregating MCDA and, potentially, other decision-making techniques to make use of their individual benefits and leading to a more holistic view of the actual consequences that come with certain decisions. This review is providing a comprehensive overview of hybrid approaches that are used in forest management planning. Today, the scientific world is facing increasing challenges regarding the evaluation of ES and the trade-offs between them, for example between provisioning and regulating services. As the preferences of multiple stakeholders are essential to improve the decision process in multi-purpose forestry, participatory and hybrid approaches turn out to be of particular importance. Accordingly, hybrid methods show great potential for becoming most relevant in future decision making. Based on the review presented here, the development of models for the use in planning processes should focus on participatory modeling and the consideration of uncertainty regarding available information.

  16. Hybrid MCDA Methods to Integrate Multiple Ecosystem Services in Forest Management Planning: A Critical Review

    Science.gov (United States)

    Uhde, Britta; Andreas Hahn, W.; Griess, Verena C.; Knoke, Thomas

    2015-08-01

    Multi-criteria decision analysis (MCDA) is a decision aid frequently used in the field of forest management planning. It includes the evaluation of multiple criteria such as the production of timber and non-timber forest products and tangible as well as intangible values of ecosystem services (ES). Hence, it is beneficial compared to those methods that take a purely financial perspective. Accordingly, MCDA methods are increasingly popular in the wide field of sustainability assessment. Hybrid approaches allow aggregating MCDA and, potentially, other decision-making techniques to make use of their individual benefits and leading to a more holistic view of the actual consequences that come with certain decisions. This review is providing a comprehensive overview of hybrid approaches that are used in forest management planning. Today, the scientific world is facing increasing challenges regarding the evaluation of ES and the trade-offs between them, for example between provisioning and regulating services. As the preferences of multiple stakeholders are essential to improve the decision process in multi-purpose forestry, participatory and hybrid approaches turn out to be of particular importance. Accordingly, hybrid methods show great potential for becoming most relevant in future decision making. Based on the review presented here, the development of models for the use in planning processes should focus on participatory modeling and the consideration of uncertainty regarding available information.

  17. Rational Selection, Criticality Assessment, and Tiering of Quality Attributes and Test Methods for Analytical Similarity Evaluation of Biosimilars.

    Science.gov (United States)

    Vandekerckhove, Kristof; Seidl, Andreas; Gutka, Hiten; Kumar, Manish; Gratzl, Gyöngyi; Keire, David; Coffey, Todd; Kuehne, Henriette

    2018-05-10

    Leading regulatory agencies recommend biosimilar assessment to proceed in a stepwise fashion, starting with a detailed analytical comparison of the structural and functional properties of the proposed biosimilar and reference product. The degree of analytical similarity determines the degree of residual uncertainty that must be addressed through downstream in vivo studies. Substantive evidence of similarity from comprehensive analytical testing may justify a targeted clinical development plan, and thus enable a shorter path to licensing. The importance of a careful design of the analytical similarity study program therefore should not be underestimated. Designing a state-of-the-art analytical similarity study meeting current regulatory requirements in regions such as the USA and EU requires a methodical approach, consisting of specific steps that far precede the work on the actual analytical study protocol. This white paper discusses scientific and methodological considerations on the process of attribute and test method selection, criticality assessment, and subsequent assignment of analytical measures to US FDA's three tiers of analytical similarity assessment. Case examples of selection of critical quality attributes and analytical methods for similarity exercises are provided to illustrate the practical implementation of the principles discussed.

  18. The principal component analysis method used with polynomial Chaos expansion to propagate uncertainties through critical transport problems

    Energy Technology Data Exchange (ETDEWEB)

    Rising, M. E.; Prinja, A. K. [Univ. of New Mexico, Dept. of Chemical and Nuclear Engineering, Albuquerque, NM 87131 (United States)

    2012-07-01

    A critical neutron transport problem with random material properties is introduced. The total cross section and the average neutron multiplicity are assumed to be uncertain, characterized by the mean and variance with a log-normal distribution. The average neutron multiplicity and the total cross section are assumed to be uncorrected and the material properties for differing materials are also assumed to be uncorrected. The principal component analysis method is used to decompose the covariance matrix into eigenvalues and eigenvectors and then 'realizations' of the material properties can be computed. A simple Monte Carlo brute force sampling of the decomposed covariance matrix is employed to obtain a benchmark result for each test problem. In order to save computational time and to characterize the moments and probability density function of the multiplication factor the polynomial chaos expansion method is employed along with the stochastic collocation method. A Gauss-Hermite quadrature set is convolved into a multidimensional tensor product quadrature set and is successfully used to compute the polynomial chaos expansion coefficients of the multiplication factor. Finally, for a particular critical fuel pin assembly the appropriate number of random variables and polynomial expansion order are investigated. (authors)

  19. Critical thinking: concept analysis from the perspective of Rodger's evolutionary method of concept analysis.

    Science.gov (United States)

    Carbogim, Fábio da Costa; Oliveira, Larissa Bertacchini de; Püschel, Vilanice Alves de Araújo

    2016-09-01

    to analyze the concept of critical thinking (CT) in Rodger's evolutionary perspective. documentary research undertaken in the Cinahl, Lilacs, Bdenf and Dedalus databases, using the keywords of 'critical thinking' and 'Nursing', without limitation based on year of publication. The data were analyzed in accordance with the stages of Rodger's conceptual model. The following were included: books and articles in full, published in Portuguese, English or Spanish, which addressed CT in the teaching and practice of Nursing; articles which did not address aspects related to the concept of CT were excluded. the sample was made up of 42 works. As a substitute term, emphasis is placed on 'analytical thinking', and, as a related factor, decision-making. In order, the most frequent preceding and consequent attributes were: ability to analyze, training of the student nurse, and clinical decision-making. As the implications of CT, emphasis is placed on achieving effective results in care for the patient, family and community. CT is a cognitive skill which involves analysis, logical reasoning and clinical judgment, geared towards the resolution of problems, and standing out in the training and practice of the nurse with a view to accurate clinical decision-making and the achieving of effective results. analisar o conceito de pensamento crítico (PC), na perspectiva evolucionista de Rodgers. pesquisa documental realizada nas bases de dados Cinahl, Lilacs, Bdenf e Dedalus, utilizando-se as palavras-chave pensamento crítico e Enfermagem, sem delimitação de ano de publicação. Os dados foram analisados conforme etapas do modelo conceitual de Rodgers. Incluíram-se livros e artigos na íntegra, publicados em português, inglês ou espanhol que abordavam o PC no ensino e prática de Enfermagem, excluindo-se estudos que não abordassem aspectos relacionados ao conceito do PC. a amostra foi constituída por 42 trabalhos. Como termo substituto, destacou-se pensamento analítico e, como

  20. Methods of securing and controlling critical infrastructure assets allocated in information and communications technology sector companies in leading

    Directory of Open Access Journals (Sweden)

    Piotr Sieńko

    2015-12-01

    Full Text Available Critical Infrastructure (CI plays a significant role in maintaining public order and national security. The state may use many different methods to protect and control CI allocated to commercial companies. This article describes the three most important ones: legislation, ownership and government institutions and agencies. The data presented in this paper is the result of research done on the most developed countries in the EU (United Kingdom, France, Germany and Italy and their strategic enterprises in the ICT sector, one of the most important sectors in any national security system.

  1. Resin purification from Dragons Blood by using sub critical solvent extraction method

    Science.gov (United States)

    Saifuddin; Nahar

    2018-04-01

    Jernang resin (dragon blood) is the world's most expensive sap. The resin obtained from jernang that grows only on the islands of Sumatra and Borneo. Jernang resin is in demand by the State of China, Hong Kong, and Singapore since they contain compounds that have the potential dracohordin as a medicinal ingredient in the biological and pharmacological activity such as antimicrobial, antiviral, antitumor and cytotoxic activity. The resin extracting process has conventionally been done by drizzly with maceration method as one way of processing jernang, which is done by people in Bireuen, Aceh. However, there are still significant obstacles, namely the quality of the yield that obtained lower than the jernang resin. The technological innovation carried out by forceful extraction process maceration by using methanol produced a yield that is higher than the extraction process maceration method carried out in Bireuen. Nevertheless, the use of methanol as a solvent would raise the production costs due to the price, which is relatively more expensive and non-environmentally friendly. To overcome the problem, this research proposed a process, which is known as subcritical solvent method. This process is cheap, and also abundant and environmentally friendly. The results show that the quality of jernang resins is better than the one that obtained by the processing group in Bireuen. The quality of the obtained jernang by maceration method is a class-A quality based on the quality specification requirements of jernang (SNI 1671: 2010) that has resin (b/b) 73%, water (w/w) of 6.8%, ash (w/b) 7%, impurity (w/w) 32%, the melting point of 88°C and red colours. While the two-stage treatment obtained a class between class-A and super quality, with the resin (b/b) 0.86%, water (w/w) of 6.5%, ash (w/w) of 2.8%, levels of impurities (w/w) of 9%, the melting point of 88 °C and dark-red colours.

  2. Application of the ultrametric distance to portfolio taxonomy. Critical approach and comparison with other methods

    Science.gov (United States)

    Skórnik-Pokarowska, Urszula; Orłowski, Arkadiusz

    2004-12-01

    We calculate the ultrametric distance between the pairs of stocks that belong to the same portfolio. The ultrametric distance allows us to distinguish groups of shares that are related. In this way, we can construct a portfolio taxonomy that can be used for constructing an efficient portfolio. We also construct a portfolio taxonomy based not only on stock prices but also on economic indices such as liquidity ratio, debt ratio and sales profitability ratio. We show that a good investment strategy can be obtained by applying to the portfolio chosen by the taxonomy method the so-called Constant Rebalanced Portfolio.

  3. Accounting for no net loss: A critical assessment of biodiversity offsetting metrics and methods.

    Science.gov (United States)

    Carreras Gamarra, Maria Jose; Lassoie, James Philip; Milder, Jeffrey

    2018-08-15

    Biodiversity offset strategies are based on the explicit calculation of both losses and gains necessary to establish ecological equivalence between impact and offset areas. Given the importance of quantifying biodiversity values, various accounting methods and metrics are continuously being developed and tested for this purpose. Considering the wide array of alternatives, selecting an appropriate one for a specific project can be not only challenging, but also crucial; accounting methods can strongly influence the biodiversity outcomes of an offsetting strategy, and if not well-suited to the context and values being offset, a no net loss outcome might not be delivered. To date there has been no systematic review or comparative classification of the available biodiversity accounting alternatives that aim at facilitating metric selection, and no tools that guide decision-makers throughout such a complex process. We fill this gap by developing a set of analyses to support (i) identifying the spectrum of available alternatives, (ii) understanding the characteristics of each and, ultimately (iii) making the most sensible and sound decision about which one to implement. The metric menu, scoring matrix, and decision tree developed can be used by biodiversity offsetting practitioners to help select an existing metric, and thus achieve successful outcomes that advance the goal of no net loss of biodiversity. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Dear Critics: Addressing Concerns and Justifying the Benefits of Photography as a Research Method

    Directory of Open Access Journals (Sweden)

    Kyle Elizabeth Miller

    2015-08-01

    Full Text Available Photography serves as an important tool for researchers to learn about the contextualized lives of individuals. This article explores the process of integrating photo elicitation interviews (PEI into research involving children and families. Much literature is dedicated to the general debate surrounding the ethics of visual methods in research, with little attention directed at the actual process of gaining study approval and publishing one's findings. There are two main critiques that researchers must face in order to conduct and disseminate studies involving visual images—ethics committees and peer reviewers. In this article, I identify and discuss some of the challenges that emerged across gaining protocol approval from an ethics committee in the United States. Ethical concerns and restrictions related to the use of photography can delay data collection and create barriers to research designs. Similarly, I describe the process of responding to reviewers' concerns as part of the publication process. Peer reviewers' lack of familiarity with the use of photography as a research tool may lead to misunderstandings and inappropriate requests for manuscript changes. While many concerns are sound, the range of benefits stemming from the use of visual data help to justify the time and energy required to defend this type of research. Implications are discussed for researchers using visual methods in their work. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1503274

  5. Predicting the local impacts of energy development: a critical guide to forecasting methods and models

    Energy Technology Data Exchange (ETDEWEB)

    Sanderson, D.; O' Hare, M.

    1977-05-01

    Models forecasting second-order impacts from energy development vary in their methodology, output, assumptions, and quality. As a rough dichotomy, they either simulate community development over time or combine various submodels providing community snapshots at selected points in time. Using one or more methods - input/output models, gravity models, econometric models, cohort-survival models, or coefficient models - they estimate energy-development-stimulated employment, population, public and private service needs, and government revenues and expenditures at some future time (ranging from annual to average year predictions) and for different governmental jurisdictions (municipal, county, state, etc.). Underlying assumptions often conflict, reflecting their different sources - historical data, comparative data, surveys, and judgments about future conditions. Model quality, measured by special features, tests, exportability and usefulness to policy-makers, reveals careful and thorough work in some cases and hurried operations with insufficient in-depth analysis in others.

  6. Remote vacuum or pressure sealing device and method for critical isolated systems

    Science.gov (United States)

    Brock, James David [Newport News, VA; Keith, Christopher D [Newport News, VA

    2012-07-10

    A remote vacuum or pressure sealing apparatus and method for making a radiation tolerant, remotely prepared seal that maintains a vacuum or pressure tight seal throughout a wide temperature range. The remote sealing apparatus includes a fixed threaded sealing surface on an isolated system, a gasket, and an insert consisting of a plug with a protruding sample holder. An insert coupling device, provided for inserting samples within the isolated system, includes a threaded fastener for cooperating with the fixed threaded sealing surface on the isolated system. The insert coupling device includes a locating pin for azimuthal orientation, coupling pins, a tooted coaxial socket wrench, and an insert coupling actuator for actuating the coupling pins. The remote aspect of the sealing apparatus maintains the isolation of the system from the user's environment, safely preserving the user and the system from detrimental effect from each respectively.

  7. Statistical modeling methods to analyze the impacts of multiunit process variability on critical quality attributes of Chinese herbal medicine tablets

    Directory of Open Access Journals (Sweden)

    Sun F

    2016-11-01

    Full Text Available Fei Sun,1 Bing Xu,1,2 Yi Zhang,1 Shengyun Dai,1 Chan Yang,1 Xianglong Cui,1 Xinyuan Shi,1,2 Yanjiang Qiao1,2 1Research Center of Traditional Chinese Medicine Information Engineering, School of Chinese Materia Medica, Beijing University of Chinese Medicine, 2Key Laboratory of Manufacture Process Control and Quality Evaluation of Chinese Medicine, Beijing, People’s Republic of China Abstract: The quality of Chinese herbal medicine tablets suffers from batch-to-batch variability due to a lack of manufacturing process understanding. In this paper, the Panax notoginseng saponins (PNS immediate release tablet was taken as the research subject. By defining the dissolution of five active pharmaceutical ingredients and the tablet tensile strength as critical quality attributes (CQAs, influences of both the manipulated process parameters introduced by an orthogonal experiment design and the intermediate granules’ properties on the CQAs were fully investigated by different chemometric methods, such as the partial least squares, the orthogonal projection to latent structures, and the multiblock partial least squares (MBPLS. By analyzing the loadings plots and variable importance in the projection indexes, the granule particle sizes and the minimal punch tip separation distance in tableting were identified as critical process parameters. Additionally, the MBPLS model suggested that the lubrication time in the final blending was also important in predicting tablet quality attributes. From the calculated block importance in the projection indexes, the tableting unit was confirmed to be the critical process unit of the manufacturing line. The results demonstrated that the combinatorial use of different multivariate modeling methods could help in understanding the complex process relationships as a whole. The output of this study can then be used to define a control strategy to improve the quality of the PNS immediate release tablet. Keywords: Panax

  8. Realization of multilayers for superconductors at critical high temperature by chemical method

    International Nuclear Information System (INIS)

    Guibadj, A.

    2009-09-01

    The aim of this research is to study buffer layers made of CeO 2 and La 2 Zr 2 O 7 for high Tc superconductors devoted to energy transportation (coated conductors). We used Metal Organic Decomposition method (MOD) for the synthesis of layers of CeO 2 /SrTiO 3 and La 2 Zr 2 O 7 /LaAlO 3 , because it is a soft and economic method well adapted to manufacture buffers layers for coated conductors. The comparison of various precursors of Cerium was made with the aim of obtaining the adequate precursor for the MOD process. Spin coating was used for depositing precursor solutions of Ce(EH) 3 and LZ(propionic) on various substrates. Thermal analyzes of these precursors allowed to determine their decomposition mode (weight loss analysis) according to the temperature, to estimate the quantity of absorbed moisture by the precursors and to determine the temperature of crystallization of the oxide. It was also used to discuss the mixed nature or not of the lanthanum-zirconium proprionate. The analyses of the microstructure and of the texture of CeO 2 and La 2 Zr 2 O 7 films are established by X-ray diffraction (scans θ-2θ, ω-scan, Φ-scan and pole figures). AFM and MEB allowed us to study roughness, topology and morphology of the surface. Heat treatments of the layers of C(EH) 3 /SrTiO 3 and (La(prop) 3 + Zr(prop) 4 )/LAO, under various atmospheres enabled us to differentiate the poly-crystalline growth from the epitaxial growth. The elimination of residual carbon in the grain boundaries, blocking the grain growth, was carried out by a control of the partial pressure of oxygen at the stage of crystallization; this step makes possible an improvement of the layers' texture. The heating rate has an influence on the nucleation which was studied. Increasing the heating rate favor the heterogeneous nucleation and decreases the number of nuclei, supporting the growth of larger epitaxial grains. Finally, we carried out the multi-layers CeO 2 /La 2 Zr 2 O 7 /LaAlO 3 and YBaCuO/CeO 2

  9. RISK ASSESSMENT IN PROJECT PLANNING USING FMEA AND CRITICAL PATH METHOD

    Directory of Open Access Journals (Sweden)

    Sandra Milena CHOLES ARVILLA

    2014-10-01

    Full Text Available This paper is based upon the research undertaken for the development of the doctoral thesis “Management of software projects based on object-oriented technology”. The study examines the existing risk management practices commonly used for classic software development. The goal is to integrate the elements of the traditional risk management methodologies to create a new agile risk management methodology. The thesis focuses on techniques that can be easily implemented in extreme programming (XP and SCRUM. This study is motivated by the following research questions: What are the elements of existing quality assurance tools that could meet the principles of agile development? And is it possible to use risk estimation for improving quality in agile projects? The thesis presents a synthesis of the most common risk management techniques, as well as an introduction to agile methods XP and SCRUM. The proposal integrates the concepts of Failure Mode and Effect Analysis into the iterative life cycle of an agile software project. The thesis presents a metamodel which integrates the concepts of agile development methodologies: SCRUM and XP with the FMEA concepts for risk quantification. The model was partly implemented into a real development project. Partial results show the improvement in early identification of failures and allowed to reconsider the Sprint plan.

  10. Inverse kinetics method with source term for subcriticality measurements during criticality approach in the IPEN/MB-01 research reactor

    International Nuclear Information System (INIS)

    Loureiro, Cesar Augusto Domingues; Santos, Adimir dos

    2009-01-01

    In reactor physics tests which are performed at the startup after refueling the commercial PWRs, it is important to monitor subcriticality continuously during criticality approach. Reactivity measurements by the inverse kinetics method are widely used during the operation of a nuclear reactor and it is possible to perform an online reactivity measurement based on the point reactor kinetics equations. This technique is successful applied at sufficiently high power level or to a core without an external neutron source where the neutron source term in point reactor kinetics equations may be neglected. For operation at low power levels, the contribution of the neutron source must be taken into account and this implies the knowledge of a quantity proportional to the source strength, and then it should be determined. Some experiments have been performed in the IPEN/MB-01 Research Reactor for the determination of the Source Term, using the Least Square Inverse Kinetics Method (LSIKM). A digital reactivity meter which neglects the source term is used to calculate the reactivity and then the source term can be determined by the LSIKM. After determining the source term, its value can be added to the algorithm and the reactivity can be determined again, considering the source term. The new digital reactivity meter can be used now to monitor reactivity during the criticality approach and the measured value for the reactivity is more precise than the meter which neglects the source term. (author)

  11. Measuring the sustainability of a natural system by using multi-criteria distance function methods: Some critical issues.

    Science.gov (United States)

    Diaz-Balteiro, L; Belavenutti, P; Ezquerro, M; González-Pachón, J; Ribeiro Nobre, S; Romero, C

    2018-05-15

    There is an important body of literature using multi-criteria distance function methods for the aggregation of a battery of sustainability indicators in order to obtain a composite index. This index is considered to be a proxy of the sustainability goodness of a natural system. Although this approach has been profusely used in the literature, it is not exempt from difficulties and potential pitfalls. Thus, in this paper, a significant number of critical issues have been identified showing different procedures capable of avoiding, or at least of mitigating, the inherent potential pitfalls associated with each one. The recommendations made in the paper could increase the theoretical soundness of the multi-criteria distance function methods when this type of approach is applied in the sustainability field, thus increasing the accuracy and realism of the sustainability measurements obtained. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. A computation method for mass flowrate predictions in critical flows of initially subcooled liquid in long channels

    International Nuclear Information System (INIS)

    Celata, G.P.; D'Annibale, F.; Farello, G.E.

    1985-01-01

    It is suggested a fast and accurate computation method for the prediction of mass flowrate in critical flows initially subcooled liquid from ''long'' discharge channels (high LID values). Starting from a previous very simple correlation proposed by the authors, further improvements in the model enable to widen the method reliability up to initial saturation conditions. A comparison of computed values with 145 experimental data regarding several investigations carried out at the Heat Transfer Laboratory (TERM/ISP, ENEA Casaccia) shows an excellent agreement. The computed data shifting from experimental ones is within ±10% for almost all data, with a slight increase towards low inlet subcoolings. The average error, for all the considered data, is 4,6%

  13. A critical analysis of one standard and five methods to monitor surface wetness and time-of-wetness

    Science.gov (United States)

    Camuffo, Dario; della Valle, Antonio; Becherini, Francesca

    2018-05-01

    Surface wetness is a synergistic factor to determine atmospheric corrosion, monument weathering, mould growth, sick buildings, etc. However, its detection and monitoring are neither easy nor homogeneous, for a number of factors that may affect readings. Various types of methods and sensors, either commercial or prototypes built in the lab, have been investigated and compared, i.e. the international standard ISO 9223 to evaluate corrosivity after wetness and time-of-wetness; indirect evaluation of wetness, based on the dew point calculated after the output of temperature and relative humidity sensors and direct measurements by means of capacitive wetness sensors, safety sensors, rain sensors (also known as leaf wetness sensors), infrared reflection sensors and fibre optic sensors. A comparison between the different methods is presented, specifying physical principles, forms of wetting to which they are respondent (i.e. condensation, ice melting, splashing drops, percolation and capillary rise), critical factors, use and cost.

  14. A critical assessment of the equal environment assumption of the twin method for schizophrenia

    Directory of Open Access Journals (Sweden)

    Roar eFosse

    2015-04-01

    Full Text Available The classical twin method (CTM is central to the view that schizophrenia is ~80% heritable. The CTM rests on the equal environments assumption (EEA that identical and fraternal twin pairs experience equivalent trait relevant environmental exposures. The EEA has not been directly tested for schizophrenia with measures of child social adversity, which is particularly etiologically relevant to the disorder. However, if child social adversity is more similar in identical than fraternal pairs in the general twin population, the EEA is unlikely to be valid for schizophrenia, a question which we tested in this study. Using results from prior twin studies, we tested if intraclass correlations for the following five categories of child social adversity are larger in identical than fraternal twins: bullying, sexual abuse, physical maltreatment, emotional neglect and abuse, and general trauma. Eleven relevant studies that encompassed 9119 twin pairs provided 24 comparisons of intraclass correlations, which we grouped into the five social exposure categories. Fisher’s z-test revealed significantly higher correlations in identical than fraternal pairs for each exposure category (z ≥ 3.53, p <.001. The difference remained consistent across gender, study site (country, sample size, whether psychometric instruments were used, whether interviewing was proximate or distant to the exposures, and whether informants were twins or third persons. Combined with other evidence that the differential intraclass correlation for child social adversity cannot be explained by evocative gene-environment covariation, our results indicate that the CTM does not provide any valid indication of genomic effects in schizophrenia.

  15. Comparative study of three methods of estimation of creatinine clearance in critically ill patients.

    Science.gov (United States)

    Blasco, V; Antonini, F; Zieleskiewicz, L; Hammad, E; Albanèse, J; Martin, C; Leone, M

    2014-05-01

    At the bedside, the reference method for creatinine clearance determination is based on the measurement of creatinine concentrations in urine and serum (mCrCl). Several models are available to calculate the creatinine clearance from the serum creatinine concentration. This observational survey aimed at testing the hypothesis that the proposed equations are unreliable to determine accurate creatinine clearance in patients admitted to intensive care unit (ICU). Creatinine clearance was determined by the use of mCrCl. Then, we compared three equations: Cockcroft-Gault (CG), Simplified Modification of Diet in Renal Disease (MDRDs), and Chronic Kidney Disease Epidemiology (CKD-EPI) in 156 consecutive patients within the first 24hours after ICU admission. We tested the hypothesis that the three equations were equivalent. The agreement between the three equations was evaluated by linear regression and Bland and Altman analysis. Bland and Altman analysis showed similar agreement between the three equations. The biases and precisions were -4.8±51, -1.3±50, and 8.2±44 for CG, MDRDs, and CKD-EPI equations, respectively (P>0.05). The precisions were similar for the three equations (P>0.05). The percentages of outliers at ±30% were 44%, 45%, and 49% for CG, MDRDs, and CKD-EPI, respectively (P>0.05). Regarding the high percentage of outliers, the use of these equations cannot be recommended in ICU patients. Copyright © 2014 Société française d’anesthésie et de réanimation (Sfar). Published by Elsevier SAS. All rights reserved.

  16. Information needs assessment of medical equipment offices based on Critical Success Factors (CSF) and Business System Planning (BSP) methods.

    Science.gov (United States)

    Khorrami, F; Ahmadi, M; Alizadeh, A; Roozbeh, N; Mohseni, S

    2015-01-01

    Introduction: Given the ever-increasing importance and value of information, providing the management with a reliable information system, which can facilitate decision-making regarding planning, organization and control, is vitally important. This study aimed to analyze and evaluate the information needs of medical equipment offices. Methods: This descriptive applied cross-sectional study was carried out in 2010. The population of the study included the managers of statistic and medical records at the offices of vice-chancellor for treatment in 39 medical universities in Iran. Data were collected by using structured questioners. With regard to different kinds of designing information systems, sampling was done by two methods, BSP (based on processes of job description) and CSF method (based on critical success factors). The data were analyzed by SPSS-16. Results: Our study showed that 41% of information needs were found to be critical success factors of managers of office. The first priority of managers was "the number of bed and bed occupancy in hospitals". Of 29 identified information needs, 62% were initial information needs of managers (from the viewpoints of managers). Of all, 4% of the information needs were obtained through the form, 14% through both the form and database, 11% through the web site, and 71% had no sources (forms, databases, web site). Conclusion: Since 71% of the information needs of medical equipment offices managers had no information sources, the development of information system in these offices seems to be necessary. Despite the important role of users in designing the information systems (identifying 62% of information needs), other scientific methods is also needed to be utilized in designing the information systems.

  17. Information needs assessment of medical equipment offices based on Critical Success Factors (CSF) and Business System Planning (BSP) methods

    Science.gov (United States)

    Khorrami, F; Ahmadi, M; Alizadeh, A; Roozbeh, N; Mohseni, S

    2015-01-01

    Introduction: Given the ever-increasing importance and value of information, providing the management with a reliable information system, which can facilitate decision-making regarding planning, organization and control, is vitally important. This study aimed to analyze and evaluate the information needs of medical equipment offices. Methods: This descriptive applied cross-sectional study was carried out in 2010. The population of the study included the managers of statistic and medical records at the offices of vice-chancellor for treatment in 39 medical universities in Iran. Data were collected by using structured questioners. With regard to different kinds of designing information systems, sampling was done by two methods, BSP (based on processes of job description) and CSF method (based on critical success factors). The data were analyzed by SPSS-16. Results: Our study showed that 41% of information needs were found to be critical success factors of managers of office. The first priority of managers was “the number of bed and bed occupancy in hospitals”. Of 29 identified information needs, 62% were initial information needs of managers (from the viewpoints of managers). Of all, 4% of the information needs were obtained through the form, 14% through both the form and database, 11% through the web site, and 71% had no sources (forms, databases, web site). Conclusion: Since 71% of the information needs of medical equipment offices managers had no information sources, the development of information system in these offices seems to be necessary. Despite the important role of users in designing the information systems (identifying 62% of information needs), other scientific methods is also needed to be utilized in designing the information systems. PMID:28255389

  18. Comparing the effects of problem-based learning and the traditional lecture method on critical thinking skills and metacognitive awareness in nursing students in a critical care nursing course.

    Science.gov (United States)

    Gholami, Mohammad; Moghadam, Parastou Kordestani; Mohammadipoor, Fatemeh; Tarahi, Mohammad Javad; Sak, Mandana; Toulabi, Tahereh; Pour, Amir Hossein Hossein

    2016-10-01

    Problem-based learning (PBL) is a method used to develop cognitive and metacognitive skills in nursing students. The present study was conducted to compare the effects of PBL and the traditional lecture method on critical thinking skills and metacognitive awareness in nursing students in a critical care nursing course. The present study was conducted with a quasi-experimental, single group, pretest-posttest design. A group of third-year nursing students (n=40) were recruited from Khorramabad School of Nursing and Midwifery in the west of Iran. The lecture method was used in one group over the first eight weeks of the first semester and PBL was adopted in the second eight weeks. Standardized self-report questionnaires including The California Critical Thinking Skills Test-B (CCTST-B) and the Metacognitive Awareness Inventory (MAI) were administered before and after the use of each of the instruction methods. Data were analyzed in SPSS using the paired t-test. No significant changes were observed in the students' critical thinking skills and metacognitive awareness after performing the lecture method. However, a significant increase was observed in the overall critical thinking score (Pmethod. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Studies of criticality Monte Carlo method convergence: use of a deterministic calculation and automated detection of the transient

    International Nuclear Information System (INIS)

    Jinaphanh, A.

    2012-01-01

    Monte Carlo criticality calculation allows to estimate the effective multiplication factor as well as local quantities such as local reaction rates. Some configurations presenting weak neutronic coupling (high burn up profile, complete reactor core,...) may induce biased estimations for k eff or reaction rates. In order to improve robustness of the iterative Monte Carlo methods, a coupling with a deterministic code was studied. An adjoint flux is obtained by a deterministic calculation and then used in the Monte Carlo. The initial guess is then automated, the sampling of fission sites is modified and the random walk of neutrons is modified using splitting and russian roulette strategies. An automated convergence detection method has been developed. It locates and suppresses the transient due to the initialization in an output series, applied here to k eff and Shannon entropy. It relies on modeling stationary series by an order 1 auto regressive process and applying statistical tests based on a Student Bridge statistics. This method can easily be extended to every output of an iterative Monte Carlo. Methods developed in this thesis are tested on different test cases. (author)

  20. Characterization of the CALIBAN Critical Assembly Neutron Spectra using Several Adjustment Methods Based on Activation Foils Measurement

    Science.gov (United States)

    Casoli, Pierre; Grégoire, Gilles; Rousseau, Guillaume; Jacquet, Xavier; Authier, Nicolas

    2016-02-01

    CALIBAN is a metallic critical assembly managed by the Criticality, Neutron Science and Measurement Department located on the French CEA Center of Valduc. The reactor is extensively used for benchmark experiments dedicated to the evaluation of nuclear data, for electronic hardening or to study the effect of the neutrons on various materials. Therefore CALIBAN irradiation characteristics and especially its central cavity neutron spectrum have to be very accurately evaluated. In order to strengthen our knowledge of this spectrum, several adjustment methods based on activation foils measurements are being studied for a few years in the laboratory. Firstly two codes included in the UMG package have been tested and compared: MAXED and GRAVEL. More recently, the CALIBAN cavity spectrum has been studied using CALMAR, a new adjustment tool currently under development at the CEA Center of Cadarache. The article will discuss and compare the results and the quality of spectrum rebuilding obtained with the UMG codes and with the CALMAR software, from a set of activation measurements carried out in the CALIBAN irradiation cavity.

  1. Characterization of the CALIBAN Critical Assembly Neutron Spectra using Several Adjustment Methods Based on Activation Foils Measurement

    Directory of Open Access Journals (Sweden)

    Casoli Pierre

    2016-01-01

    Full Text Available CALIBAN is a metallic critical assembly managed by the Criticality, Neutron Science and Measurement Department located on the French CEA Center of Valduc. The reactor is extensively used for benchmark experiments dedicated to the evaluation of nuclear data, for electronic hardening or to study the effect of the neutrons on various materials. Therefore CALIBAN irradiation characteristics and especially its central cavity neutron spectrum have to be very accurately evaluated. In order to strengthen our knowledge of this spectrum, several adjustment methods based on activation foils measurements are being studied for a few years in the laboratory. Firstly two codes included in the UMG package have been tested and compared: MAXED and GRAVEL. More recently, the CALIBAN cavity spectrum has been studied using CALMAR, a new adjustment tool currently under development at the CEA Center of Cadarache. The article will discuss and compare the results and the quality of spectrum rebuilding obtained with the UMG codes and with the CALMAR software, from a set of activation measurements carried out in the CALIBAN irradiation cavity.

  2. The effect of strongly anisotropic scattering on the critical size of a slab in one-speed neutron transport theory: Modified UN method

    International Nuclear Information System (INIS)

    Öztürk, Hakan

    2014-01-01

    Highlights: • The criticality problem for one-speed neutrons in homogeneous slab is investigated. • A combination of forward–backward and linear anisotropy is used. • The effect of the strongly anisotropic scattering on the critical size is analyzed. - Abstract: The criticality problem for one-speed neutrons in a uniform finite slab is studied in the case of a combination of forward and backward scattering with linearly anisotropic scattering using U N method based on the Chebyshev polynomials of second kind. The effect of the linear anisotropy on the critical thickness of the slab is investigated. The critical slab thicknesses are calculated by using Marshak boundary condition for various values of the anisotropy parameters and they are presented in the tables. In comparison to the results obtained by other methods, the results of this study are in compatible with the former ones

  3. The development and validation of the Blended Socratic Method of Teaching (BSMT: An instructional model to enhance critical thinking skills of undergraduate business students

    Directory of Open Access Journals (Sweden)

    Eugenia Arazo Boa

    2018-01-01

    Full Text Available Enhancing critical thinking skills is one of the paramount goals of many educational institutions. This study presents the development and validation of the Blended Socratic Method of Teaching (BSMT, a teaching model intended to foster critical thinking skills of business students in the undergraduate level. The main objectives of the study were to 1 to survey the critical thinking skills of undergraduate business students, and 2 to develop and validate the BSMT model designed to enhance critical thinking skills. The research procedure comprised of two phases related to the two research objectives: 1 surveying the critical thinking skills of 371 undergraduate business students at Naresuan University International College focusing on the three critical thinking competencies of the RED model—recognize assumptions, evaluate arguments, and draw conclusion, and the determination of the level of their critical thinking; and 2 developing the instructional model followed by validation of the model by five experts. The results of the study were: 1 the undergraduate business students have deficient critical thinking based on the RED Model competencies as they scored “below average” on the critical thinking appraisal, and 2 the developed model comprised six elements: focus, syntax, principles of reaction, the social system, the support system, and application. The experts were in complete agreement that the model is “highly appropriate” in improving the critical thinking skills of the business students. The main essence of the model is the syntax comprising of five steps: group assignment, analysis and writing of case studies; group presentation of the business case analysis in class; Socratic discussion/questioning in class; posting of the case study on the class Facebook account; and online Socratic discussion/questioning. The BSMT model is an authentic and comprehensive model combining the Socratic method of teaching, information and

  4. Using the partial least squares (PLS) method to establish critical success factor interdependence in ERP implementation projects

    OpenAIRE

    Esteves, José; Pastor Collado, Juan Antonio; Casanovas Garcia, Josep

    2002-01-01

    This technical research report proposes the usage of a statistical approach named Partial Least squares (PLS) to define the relationships between critical success factors for ERP implementation projects. In previous research work, we developed a unified model of critical success factors for ERP implementation projects. Some researchers have evidenced the relationships between these critical success factors, however no one has defined in a form...

  5. Source-jerk method for application on ADS neutronics study The ADS is stated for Accelerator Driven sub-critical System

    CERN Document Server

    Zhu Qing Fu; Li Yi; Xia Pu; Zheng Wu Qing; Zhu Guo Sheng

    2003-01-01

    The paper is concerned in the source-jerk method used to measure the sub-criticality, and the sub-critical experiment facility, which is used for the study on the neutronics of ADS, driven by external neutron source sup 2 sup 5 sup 2 Cf. The effects of the location of neutron source and material buffer where is at the location of the pipe of proton beam and target of fission-product dispersion on the sub-criticality of reactor are studied by source-jerk method

  6. E-learning for Critical Thinking: Using Nominal Focus Group Method to Inform Software Content and Design.

    Science.gov (United States)

    Parker, Steve; Mayner, Lidia; Michael Gillham, David

    2015-12-01

    Undergraduate nursing students are often confused by multiple understandings of critical thinking. In response to this situation, the Critiique for critical thinking (CCT) project was implemented to provide consistent structured guidance about critical thinking. This paper introduces Critiique software, describes initial validation of the content of this critical thinking tool and explores wider applications of the Critiique software. Critiique is flexible, authorable software that guides students step-by-step through critical appraisal of research papers. The spelling of Critiique was deliberate, so as to acquire a unique web domain name and associated logo. The CCT project involved implementation of a modified nominal focus group process with academic staff working together to establish common understandings of critical thinking. Previous work established a consensus about critical thinking in nursing and provided a starting point for the focus groups. The study was conducted at an Australian university campus with the focus group guided by open ended questions. Focus group data established categories of content that academic staff identified as important for teaching critical thinking. This emerging focus group data was then used to inform modification of Critiique software so that students had access to consistent and structured guidance in relation to critical thinking and critical appraisal. The project succeeded in using focus group data from academics to inform software development while at the same time retaining the benefits of broader philosophical dimensions of critical thinking.

  7. Evaluation of the clinical process in a critical care information system using the Lean method: a case study

    Directory of Open Access Journals (Sweden)

    Yusof Maryati Mohd

    2012-12-01

    Full Text Available Abstract Background There are numerous applications for Health Information Systems (HIS that support specific tasks in the clinical workflow. The Lean method has been used increasingly to optimize clinical workflows, by removing waste and shortening the delivery cycle time. There are a limited number of studies on Lean applications related to HIS. Therefore, we applied the Lean method to evaluate the clinical processes related to HIS, in order to evaluate its efficiency in removing waste and optimizing the process flow. This paper presents the evaluation findings of these clinical processes, with regards to a critical care information system (CCIS, known as IntelliVue Clinical Information Portfolio (ICIP, and recommends solutions to the problems that were identified during the study. Methods We conducted a case study under actual clinical settings, to investigate how the Lean method can be used to improve the clinical process. We used observations, interviews, and document analysis, to achieve our stated goal. We also applied two tools from the Lean methodology, namely the Value Stream Mapping and the A3 problem-solving tools. We used eVSM software to plot the Value Stream Map and A3 reports. Results We identified a number of problems related to inefficiency and waste in the clinical process, and proposed an improved process model. Conclusions The case study findings show that the Value Stream Mapping and the A3 reports can be used as tools to identify waste and integrate the process steps more efficiently. We also proposed a standardized and improved clinical process model and suggested an integrated information system that combines database and software applications to reduce waste and data redundancy.

  8. A prediction method of the effect of radial heat flux distribution on critical heat flux in CANDU fuel bundles

    International Nuclear Information System (INIS)

    Yuan, Lan Qin; Yang, Jun; Harrison, Noel

    2014-01-01

    Fuel irradiation experiments to study fuel behaviors have been performed in the experimental loops of the National Research Universal (NRU) Reactor at Atomic Energy of Canada Limited (AECL) Chalk River Laboratories (CRL) in support of the development of new fuel technologies. Before initiating a fuel irradiation experiment, the experimental proposal must be approved to ensure that the test fuel strings put into the NRU loops meet safety margin requirements in critical heat flux (CHF). The fuel strings in irradiation experiments can have varying degrees of fuel enrichment and burnup, resulting in large variations in radial heat flux distribution (RFD). CHF experiments performed in Freon flow at CRL for full-scale bundle strings with a number of RFDs showed a strong effect of RFD on CHF. A prediction method was derived based on experimental CHF data to account for the RFD effect on CHF. It provides good CHF predictions for various RFDs as compared to the data. However, the range of the tested RFDs in the CHF experiments is not as wide as that required in the fuel irradiation experiments. The applicability of the prediction method needs to be examined for the RFDs beyond the range tested by the CHF experiments. The Canadian subchannel code ASSERT-PV was employed to simulate the CHF behavior for RFDs that would be encountered in fuel irradiation experiments. The CHF predictions using the derived method were compared with the ASSERT simulations. It was observed that the CHF predictions agree well with the ASSERT simulations in terms of CHF, confirming the applicability of the prediction method in fuel irradiation experiments. (author)

  9. A novel, rapid and automated conductometric method to evaluate surfactant-cells interactions by means of critical micellar concentration analysis.

    Science.gov (United States)

    Tiecco, Matteo; Corte, Laura; Roscini, Luca; Colabella, Claudia; Germani, Raimondo; Cardinali, Gianluigi

    2014-07-25

    Conductometry is widely used to determine critical micellar concentration and micellar aggregates surface properties of amphiphiles. Current conductivity experiments of surfactant solutions are typically carried out by manual pipetting, yielding some tens reading points within a couple of hours. In order to study the properties of surfactant-cells interactions, each amphiphile must be tested in different conditions against several types of cells. This calls for complex experimental designs making the application of current methods seriously time consuming, especially because long experiments risk to determine alterations of cells, independently of the surfactant action. In this paper we present a novel, accurate and rapid automated procedure to obtain conductometric curves with several hundreds reading points within tens of minutes. The method was validated with surfactant solutions alone and in combination with Saccharomyces cerevisiae cells. An easy-to use R script, calculates conductometric parameters and their statistical significance with a graphic interface to visualize data and results. The validations showed that indeed the procedure works in the same manner with surfactant alone or in combination with cells, yielding around 1000 reading points within 20 min and with high accuracy, as determined by the regression analysis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  10. On the suitability of fast and frugal heuristics for designing values clarification methods in patient decision aids: a critical analysis.

    Science.gov (United States)

    Pieterse, Arwen H; de Vries, Marieke

    2013-09-01

    Increasingly, patient decision aids and values clarification methods (VCMs) are being developed to support patients in making preference-sensitive health-care decisions. Many VCMs encourage extensive deliberation about options, without solid theoretical or empirical evidence showing that deliberation is advantageous. Research suggests that simple, fast and frugal heuristic decision strategies sometimes result in better judgments and decisions. Durand et al. have developed two fast and frugal heuristic-based VCMs. To critically analyse the suitability of the 'take the best' (TTB) and 'tallying' fast and frugal heuristics in the context of patient decision making. Analysis of the structural similarities between the environments in which the TTB and tallying heuristics have been proven successful and the context of patient decision making and of the potential of these heuristic decision processes to support patient decision making. The specific nature of patient preference-sensitive decision making does not seem to resemble environments in which the TTB and tallying heuristics have proven successful. Encouraging patients to consider less rather than more relevant information potentially even deteriorates their values clarification process. Values clarification methods promoting the use of more intuitive decision strategies may sometimes be more effective. Nevertheless, we strongly recommend further theoretical thinking about the expected value of such heuristics and of other more intuitive decision strategies in this context, as well as empirical assessments of the mechanisms by which inducing such decision strategies may impact the quality and outcome of values clarification. © 2011 John Wiley & Sons Ltd.

  11. Hazard analysis critical control point (HACCP) in public catering services: a modified method, combined to bacteriologic assay.

    Science.gov (United States)

    Ferrari, P

    1992-01-01

    During 1990 and 1991 the Veterinary and Public Health Services of USL 35 of Ravenna carried out a research programme aimed at the control of food-borne diseases in the sector of public catering services, in collaboration with the Public Health Laboratory (Presidio Multizonale di Prevenzione). The objectives were: obtaining sure information about health hazards in public catering services; checking structural characteristics and equipment of workrooms in restaurants, hotels and refectories; verifying food preparation and preservation methods; promoting health education to increase employees' awareness of hygiene-related problems. The first objective, evaluation of the level of the control of the workrooms exerted on the food contamination hazard by pathogenic or potentially pathogenic organisms, was carried out by allotting specific scores to several characteristics of laboratories or workers' habits, as suggested by the "Hazard Analysis Critical Control Point" (HACCP) method for butcher's shops and fish markets. Five hundred ninety-eight public catering service units have been inspected in restaurants, hotels, school-refectories, factories, hospitals and social houses; 2,097 bacteriological examinations by agar-contact plates and swabs were carried out; 118 preserved-food temperatures were measured, especially in deep-frozen and cooked food; 70 food specimens were tested to search for Salmonella spp. and Staphylococcus aureus and measure Total Aerobic Mesophilic Weight. The presence of Enterobacteriaceae and Escherichia coli was also tested.

  12. A meta-analysis of the effects of non-traditional teaching methods on the critical thinking abilities of nursing students.

    Science.gov (United States)

    Lee, JuHee; Lee, Yoonju; Gong, SaeLom; Bae, Juyeon; Choi, Moonki

    2016-09-15

    Scientific framework is important in designing curricula and evaluating students in the field of education and clinical practice. The purpose of this study was to examine the effectiveness of non-traditional educational methods on critical thinking skills. A systematic review approach was applied. Studies published in peer-reviewed journals from January 2001 to December 2014 were searched using electronic databases and major education journals. A meta-analysis was performed using Review Manager 5.2. Reviewing the included studies, the California Critical Thinking Dispositions Inventory (CCTDI) and California Critical Thinking Skills Test (CCTST) were used to assess the effectiveness of critical thinking in the meta-analysis. The eight CCTDI datasets showed that non- traditional teaching methods (i.e., no lectures) were more effective compared to control groups (standardized mean difference [SMD]: 0.42, 95 % confidence interval [CI]: 0.26-0.57, p teaching and learning methods in these studies were also had significantly more effects when compared to the control groups (SMD: 0.29, 95 % CI: 0.10-0.48, p = 0.003). This research showed that new teaching and learning methods designed to improve critical thinking were generally effective at enhancing critical thinking dispositions.

  13. Multi-criteria decision making to support waste management: A critical review of current practices and methods.

    Science.gov (United States)

    Goulart Coelho, Lineker M; Lange, Liséte C; Coelho, Hosmanny Mg

    2017-01-01

    Solid waste management is a complex domain involving the interaction of several dimensions; thus, its analysis and control impose continuous challenges for decision makers. In this context, multi-criteria decision-making models have become important and convenient supporting tools for solid waste management because they can handle problems involving multiple dimensions and conflicting criteria. However, the selection of the multi-criteria decision-making method is a hard task since there are several multi-criteria decision-making approaches, each one with a large number of variants whose applicability depends on information availability and the aim of the study. Therefore, to support researchers and decision makers, the objectives of this article are to present a literature review of multi-criteria decision-making applications used in solid waste management, offer a critical assessment of the current practices, and provide suggestions for future works. A brief review of fundamental concepts on this topic is first provided, followed by the analysis of 260 articles related to the application of multi-criteria decision making in solid waste management. These studies were investigated in terms of the methodology, including specific steps such as normalisation, weighting, and sensitivity analysis. In addition, information related to waste type, the study objective, and aspects considered was recorded. From the articles analysed it is noted that studies using multi-criteria decision making in solid waste management are predominantly addressed to problems related to municipal solid waste involving facility location or management strategy.

  14. The use of a modified pairwise comparison method in evaluating critical success factors for community-based rural homestay programmes

    Science.gov (United States)

    Daud, Shahidah Md; Ramli, Razamin; Kasim, Maznah Mat; Kayat, Kalsom; Razak, Rafidah Abd

    2014-12-01

    Tourism industry has become the highlighted sector which has amazingly increased the national income level. Despite the tourism industry being one of the highest income generating sectors, Homestay Programme as a Community-Based Tourism (CBT) product in Malaysia does not absorbed much of the incoming wealth. Homestay Programme refers to a programme in a community where a tourist stays together with a host family and experiences the everyday way of life of the family in both direct and indirect manner. There are over 100 Homestay Programme currently being registered with the Ministry of Culture and Tourism Malaysia which mostly are located in rural areas, but only a few excel and enjoying the fruit of the booming industry. Hence, this article seeks to identify the critical success factors for a Community-Based Rural Homestay Programme in Malaysia. A modified pairwise method is utilized to further evaluate the identified success factors in a more meaningful way. The findings will help Homestay Programme function as a community development tool that manages tourism resources. Thus, help the community in improving local economy and creating job opportunities.

  15. Study of modification methods of probes for critical-dimension atomic-force microscopy by the deposition of carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Ageev, O. A., E-mail: ageev@sfedu.ru [Southern Federal University, Institute for Nanotechnologies, Electronics, and Electronic Equipment Engineering (Russian Federation); Bykov, Al. V. [NT-MDT (Russian Federation); Kolomiitsev, A. S.; Konoplev, B. G.; Rubashkina, M. V.; Smirnov, V. A.; Tsukanova, O. G. [Southern Federal University, Institute for Nanotechnologies, Electronics, and Electronic Equipment Engineering (Russian Federation)

    2015-12-15

    The results of an experimental study of the modification of probes for critical-dimension atomicforce microscopy (CD-AFM) by the deposition of carbon nanotubes (CNTs) to improve the accuracy with which the surface roughness of vertical walls is determined in submicrometer structures are presented. Methods of the deposition of an individual CNT onto the tip of an AFM probe via mechanical and electrostatic interaction between the probe and an array of vertically aligned carbon nanotubes (VACNTs) are studied. It is shown that, when the distance between the AFM tip and a VACNT array is 1 nm and the applied voltage is within the range 20–30 V, an individual carbon nanotube is deposited onto the tip. On the basis of the results obtained in the study, a probe with a carbon nanotube on its tip (CNT probe) with a radius of 7 nm and an aspect ratio of 1:15 is formed. Analysis of the CNT probe demonstrates that its use improves the resolution and accuracy of AFM measurements, compared with the commercial probe, and also makes it possible to determine the roughness of the vertical walls of high-aspect structures by CD-AFM. The results obtained can be used to develop technological processes for the fabrication and reconditioning of special AFM probes, including those for CD-AFM, and procedures for the interoperational express monitoring of technological process parameters in the manufacturing of elements for micro- and nanoelectronics and micro- and nanosystem engineering.

  16. One-sided muon tomography - A portable method for imaging critical infrastructure with a single muon detector

    Energy Technology Data Exchange (ETDEWEB)

    Boniface, K., E-mail: bonifak@mcmaster.ca [McMaster Univ., Hamilton, Ontario (Canada); Jonkmans, G. [Defence R& D Canada, Centre for Security Science, Ottawa, Ontario (Canada); Anghel, V.; Erlandson, A.; Thompson, M.; Livingstone, S. [Canadian Nuclear Laboratories, Chalk River, Ontario (Canada)

    2014-07-01

    High-energy muons generated from cosmic-ray particle showers have been shown to exhibit properties ideal for imaging the interior of large structures. This paper explores the possibility of using a single portable muon detector in conjunction with image reconstruction methods used in nuclear medicine to reconstruct a 3D image of the interior of man-made large structures such as the Zero Energy Deuterium (ZED-2) research reactor at Atomic Energy of Canada Ltd (AECL) Chalk River Laboratories (CRL). The ZED-2 reactor core and muon detector arrangement are modeled in GEANT4 and measurements of the resultant muon throughput and angular distribution at several angles of rotation around the reactor are generated. Statistical analysis is then performed on these measurements based on the well-defined flux and angular distribution of muons expected near the surface of the earth. The results of this analysis are shown to produce reconstructed images of the spatial distribution of nuclear fuel within the core for multiple fuel configurations. This “one-sided tomography” concept is a possible candidate for examining the internal structure of larger critical facilities, for example the Fukushima Daiichi power plant where the integrity of the containment infrastructure and the location of the reactor fuel is unknown. (author)

  17. Pyrene absorption can be a convenient method for probing critical micellar concentration (cmc) and indexing micellar polarity.

    Science.gov (United States)

    Basu Ray, Gargi; Chakraborty, Indranil; Moulik, Satya P

    2006-02-01

    The critical micellar concentration (cmc) of both ionic and non-ionic surfactants can be conveniently determined from the measurements of UV absorption of pyrene in surfactant solution. The results on a number of surfactants have agreed with that realized from pyrene fluorescence measurements as well as that obtained following conductometric, tensiometric and calorimetric methods. The absorbance vs [surfactant] profiles for all the major UV spectral peaks of pyrene have been found to be sigmoidal in nature which were analyzed according to Sigmoidal-Boltzmann equation (SBE) to evaluate the cmcs of the studied surfactants. The difference between the initial and the final asymptotes (a(i) and a(f), respectively) of the sigmoidal profile, Delta a = (a(f)-a(i)) and the slope of the sigmoid, S(sig) have been observed to depend on the type of the surfactant. The Delta a has shown a linear correlation with the ratio of the fluorescence intensities of the first and the third vibronic peaks, I1/I3 of pyrene which is considered as a measure of the environmental polarity (herein micellar interior) of the probe (pyrene). Thus, Delta a values have the prospect for use as another index for the estimation of polarity of micellar interior.

  18. A Novel Application of the Multichannel Analysis of Surface Waves (MASW) Method for Estimating the Critical Zone Thicknes

    Science.gov (United States)

    Nelson, S.; Yaede, J.; McBride, J. H.; Park, C.; Turnbull, S. J.; Tingey, D. G.

    2014-12-01

    MASW approaches are suitable for the accurate measurement of variably thick weathering profiles by producing shear-wave (Vs) profiles. The critical zone (CZ) base is usually a transitional boundary, which is captured by MASW but not by conventional seismic reflection techniques. Modified MASW methods were used in Hawaii, USA to extend the investigative depth of saprolite (kaolin clays, Fe-oxides) thickness calibrated against wells with geologic logs. Active-source ± passive dispersion curves produced improved low-frequency fundamental modes by combining records with varying source-receiver offsets, enabling the generation of Vs profiles to >50 m depth. The top of unaltered bedrock occurs at a Vs of >~500 m/s. Intra-saprolite high Vs zones probably represent aa flow interiors with fewer primary discontinuities (vesicles and fractures), therefore imparting higher secondary stiffness than altered pahoehoe and pyroclastic material. The MASW approach permits measuring CZ thicknesses at discrete locations rapidly, inexpensively, and without drilling. For example, employed on slopes of the Koolau Volcano (neither aggrading nor degrading), the downward rate of advance of the weathering front of the CZ varies from 0.02 to 0.03 mm/yr in wet and ~0.01 mm/yr in dry areas. This compares well with recent work based on solute mass fluxes averaged over large areas. MASW can be deployed in a variety of settings where rapid estimation of the CZ thickness at particular locations is desired.

  19. Development of Knowledge, Awareness, Global Warming Decreasing Behavior and Critical Thinking of Grade 11 Students Using the Four Noble Truths Method with Meta-Cognitive Techniques

    Science.gov (United States)

    Chattuchai, Sakkarin; Singseewo, Adisak; Suksringarm, Paitool

    2015-01-01

    This study aims to investigate the effects of learning environmental education on the knowledge, awareness, global warming decreasing behavior, and critical thinking of eighty grade 11 students from two classes. The Four Noble Truths method with metacognitive techniques and traditional teaching method were used for the investigation. The sample…

  20. The Use of Orientation/Decision/Do/Discuss/Reflect (OD3R) Method to Increase Critical Thinking Skill and Practical Skill in Biochemistry Learning

    Science.gov (United States)

    Anwar, Yunita Arian Sani; Senam, Senam; Laksono, Endang W.

    2018-01-01

    We have developed an OD3R method that can be applied on Biochemistry learning. This OD3R consists of 5 phases: orientation, decision, do, discuss, and reflect to connect lessons in the class with practice in the laboratory. Implementation of OD3R method was done in 2 universities in Yogyakarta to increase critical thinking skill and practical…

  1. An efficient reliable method to estimate the vaporization enthalpy of pure substances according to the normal boiling temperature and critical properties

    OpenAIRE

    Mehmandoust, Babak; Sanjari, Ehsan; Vatani, Mostafa

    2014-01-01

    The heat of vaporization of a pure substance at its normal boiling temperature is a very important property in many chemical processes. In this work, a new empirical method was developed to predict vaporization enthalpy of pure substances. This equation is a function of normal boiling temperature, critical temperature, and critical pressure. The presented model is simple to use and provides an improvement over the existing equations for 452 pure substances in wide boiling range. The results s...

  2. Development of classification and prediction methods of critical heat flux using fuzzy theory and artificial neural networks

    International Nuclear Information System (INIS)

    Moon, Sang Ki

    1995-02-01

    This thesis applies new information techniques, artificial neural networks, (ANNs) and fuzzy theory, to the investigation of the critical heat flux (CHF) phenomenon for water flow in vertical round tubes. The work performed are (a) classification and prediction of CHF based on fuzzy clustering and ANN, (b) prediction and parametric trends analysis of CHF using ANN with the introduction of dimensionless parameters, and (c) detection of CHF occurrence using fuzzy rule and spatiotemporal neural network (STN). Fuzzy clustering and ANN are used for classification and prediction of the CHF using primary system parameters. The fuzzy clustering classifies the experimental CHF data into a few data clusters (data groups) according to the data characteristics. After classification of the experimental data, the characteristics of the resulted clusters are discussed with emphasis on the distribution of the experimental conditions and physical mechanisms. The CHF data in each group are trained in an artificial neural network to predict the CHF. The artificial neural network adjusts the weight so as to minimize the prediction error within the corresponding cluster. Application of the proposed method to the KAIST CHF data bank shows good prediction capability of the CHF, better than other existing methods. Parametric trends of the CHF are analyzed by applying artificial neural networks to a CHF data base for water flow in uniformly heated vertical round tubes. The analyses are performed from three viewpoints, i.e., for fixed inlet conditions, for fixed exit conditions, and based on local conditions hypothesis. In order to remove the necessity of data classification, Katto and Groeneveld et al.'s dimensionless parameters are introduced in training the ANNs with the experimental CHF data. The trained ANNs predict the CHF better than any other conventional correlations, showing RMS error of 8.9%, 13.1%, and 19.3% for fixed inlet conditions, for fixed exit conditions, and for local

  3. Managing Method: A Critical Inquiry into Language Policy in a Tertiary Institution in the United Arab Emirates

    Science.gov (United States)

    Hunt, Neil D.

    2012-01-01

    The development of critical sensibilities in English Language Teaching (ELT) in recent years has seen challenges to assumptions and methodologies in the field, placing an explicit focus on the manifestation of structures and relations of power. The critical stance affords a growing acceptance of English Language Teaching as a complex situated…

  4. Comparing the Effects of Simulation-Based and Traditional Teaching Methods on the Critical Thinking Abilities and Self-Confidence of Nursing Students.

    Science.gov (United States)

    AlAmrani, Mashael-Hasan; AlAmmar, Kamila-Ahmad; AlQahtani, Sarah-Saad; Salem, Olfat A

    2017-10-10

    Critical thinking and self-confidence are imperative to success in clinical practice. Educators should use teaching strategies that will help students enhance their critical thinking and self-confidence in complex content such as electrocardiogram interpretation. Therefore, teaching electrocardiogram interpretation to students is important for nurse educators. This study compares the effect of simulation-based and traditional teaching methods on the critical thinking and self-confidence of students during electrocardiogram interpretation sessions. Thirty undergraduate nursing students volunteered to participate in this study. The participants were divided into intervention and control groups, which were taught respectively using the simulation-based and traditional teaching programs. All of the participants were asked to complete the study instrumentpretest and posttest to measure their critical thinking and self-confidence. Improvement was observed in the control and experimental groups with respect to critical thinking and self-confidence, as evidenced by the results of the paired samples t test and the Wilcoxon signed-rank test (p .05). This study evaluated an innovative simulation-based teaching method for nurses. No significant differences in outcomes were identified between the simulator-based and traditional teaching methods, indicating that well-implemented educational programs that use either teaching method effectively promote critical thinking and self-confidence in nursing students. Nurse educators are encouraged to design educational plans with clear objectives to improve the critical thinking and self-confidence of their students. Future research should compare the effects of several teaching sessions using each method in a larger sample.

  5. EFFECTS OF TWO METHODS OF INSTRUCTION ON STUDENTS’ CRITICAL RESPONSE TO PROSE LITERATURE TEXT IN ENGLISH IN SOME SECONDARY SCHOOLS IN BENIN CITY

    Directory of Open Access Journals (Sweden)

    F. O. EZEOKOLI

    2016-08-01

    Full Text Available This study investigated the effects of two methods of instruction on secondary school students’ critical response to Prose Literature text. The study adopted a pretest, posttest, control group quasi experimental design. The participants in the study were 84 Senior Secondary II students of Literature-in-English purposively selected from four Schools in Ikpoba-Okha Local Government Area of Edo State. Two intact classes were randomly assigned to each of the treatment and control groups. Three hypotheses were tested at 0.05 alpha level. The instruments used were: Critical Response to Prose Literature Test (r = .75, Questionnaire on Home Background of Students (r = .82, and Critical Response to Prose Literature Test Marking Guide. Data obtained were subjected to Analysis of Covariance and graph. The results showed significant main effect of treatment on students’ critical response to Prose Literature (F (1, 77 = 44.731; p < .05. Students exposed to Engagement Strategies Method performed better than those exposed to the Conventional Method of instruction. Further, home background of students had no significant effect on students’ critical response to Prose Literature text (F (2, 77 = 4.902; p < .05. There was significant interaction effect of treatment and home background of students on students’ critical response to Prose Literature text (F (2, 77 = 3.508; p < .05. It was concluded that Engagement Strategies Method is effective in promoting students’ critical response to Prose Literature text. Teachers of Literature-in-English should employ Engagement Strategies Method in teaching Prose Literature to students in Senior Secondary Schools.

  6. Observability in electric power networks: identification critical measures methods; Observabilidade em redes de energia eletrica: metodos de identificacao de medidas criticas

    Energy Technology Data Exchange (ETDEWEB)

    London Junior, Joao Bosco Augusto

    1997-07-01

    One of the most important functions of the control and operation centers is to maintain service reliability in a electrical power system. In order to obtain a reliable operation of the power system, it is important to identify the critical measurements, and then to improve the measurement system using pseudo measurements. The goal of this work is to determine more efficient methods for critical measurement identification. A brief review of the some methods for observability analysis as well as two methodologies to identify critical measurements are presented. The first method has a combinatorial nature; the second one is supported by uni modular M matrix (incidence matrix of measurements for branches) and A matrix (incidence matrix of branch for nodes). The second method needs a combinatorial algorithm to be feasible, so that it becomes a slow method. Two new methods for critical measurements identification are presented in this work: the first one is based on the theory developed by Bretas (1996a), to analyse observability using graph paths; the second methods is supported y the Slutsker and Scudder (1987) theory, where identification is reached throughout the analysis of the jacobian matrix. (author)

  7. Critical study of the dispersive n- 90Zr mean field by means of a new variational method

    Science.gov (United States)

    Mahaux, C.; Sartor, R.

    1994-02-01

    A new variational method is developed for the construction of the dispersive nucleon-nucleus mean field at negative and positive energies. Like the variational moment approach that we had previously proposed, the new method only uses phenomenological optical-model potentials as input. It is simpler and more flexible than the previous approach. It is applied to a critical investigation of the n- 90Zr mean field between -25 and +25 MeV. This system is of particular interest because conflicting results had recently been obtained by two different groups. While the imaginary parts of the phenomenological optical-model potentials provided by these two groups are similar, their real parts are quite different. Nevertheless, we demonstrate that these two sets of phenomenological optical-model potentials are both compatible with the dispersion relation which connects the real and imaginary parts of the mean field. Previous hints to the contrary, by one of the two other groups, are shown to be due to unjustified approximations. A striking outcome of the present study is that it is important to explicitly introduce volume absorption in the dispersion relation, although volume absorption is negligible in the energy domain investigated here. Because of the existence of two sets of phenomenological optical-model potentials, our variational method yields two dispersive mean fields whose real parts are quite different at small or negative energies. No preference for one of the two dispersive mean fields can be expressed on purely empirical grounds since they both yield fair agreement with the experimental cross sections as well as with the observed energies of the bound single-particle states. However, we argue that one of these two mean fields is physically more meaningful, because the radial shape of its Hartree-Fock type component is independent of energy, as expected on theoretical grounds. This preferred mean field is very close to the one which had been obtained by the Ohio

  8. Complementary role of critical integral experiment and power reactor start-up experiments for LMFBR neutronics data and method validation

    International Nuclear Information System (INIS)

    Salvatores, M.

    1986-09-01

    Both critical experiments and power reactor results play at present a complementary role in reducing the uncertainties in Key design parameters for LMFBR, which can be relevant for the economic performances of this type of reactors

  9. An efficient reliable method to estimate the vaporization enthalpy of pure substances according to the normal boiling temperature and critical properties

    Directory of Open Access Journals (Sweden)

    Babak Mehmandoust

    2014-03-01

    Full Text Available The heat of vaporization of a pure substance at its normal boiling temperature is a very important property in many chemical processes. In this work, a new empirical method was developed to predict vaporization enthalpy of pure substances. This equation is a function of normal boiling temperature, critical temperature, and critical pressure. The presented model is simple to use and provides an improvement over the existing equations for 452 pure substances in wide boiling range. The results showed that the proposed correlation is more accurate than the literature methods for pure substances in a wide boiling range (20.3–722 K.

  10. An efficient reliable method to estimate the vaporization enthalpy of pure substances according to the normal boiling temperature and critical properties.

    Science.gov (United States)

    Mehmandoust, Babak; Sanjari, Ehsan; Vatani, Mostafa

    2014-03-01

    The heat of vaporization of a pure substance at its normal boiling temperature is a very important property in many chemical processes. In this work, a new empirical method was developed to predict vaporization enthalpy of pure substances. This equation is a function of normal boiling temperature, critical temperature, and critical pressure. The presented model is simple to use and provides an improvement over the existing equations for 452 pure substances in wide boiling range. The results showed that the proposed correlation is more accurate than the literature methods for pure substances in a wide boiling range (20.3-722 K).

  11. Characterization of the CALIBAN Critical Assembly Neutron Spectra using Several Adjustment Methods Based on Activation Foils Measurement

    OpenAIRE

    Casoli Pierre; Grégoire Gilles; Rousseau Guillaume; Jacquet Xavier; Authier Nicolas

    2016-01-01

    CALIBAN is a metallic critical assembly managed by the Criticality, Neutron Science and Measurement Department located on the French CEA Center of Valduc. The reactor is extensively used for benchmark experiments dedicated to the evaluation of nuclear data, for electronic hardening or to study the effect of the neutrons on various materials. Therefore CALIBAN irradiation characteristics and especially its central cavity neutron spectrum have to be very accurately evaluated. In order to streng...

  12. Comparison between “Problem-Based Learning” and “Question & Answer” Educational Methods on Environmental Health Students’ Attitude to Critical Thinking

    Directory of Open Access Journals (Sweden)

    Salehi L

    2015-04-01

    Full Text Available  Aims: Critical thinking has the 2 aspects skill and attitude. The skill aspect will not take place without the attitude to critical thinking. The aim of this study was to compare between problem-based and question-answer learning methods on critical thinking attitude of environmental health students.  Instrument & Methods: In this quasi-experimental study all 27 environmental health students of Alborz University of Medical Sciences were entered the study by census method. Critical thinking attitudes’ parameters were studied by the California critical thinking disposition inventory (CCTDI before and after the intervention. The problem-based learning group (14 persons held some scenarios for studying and investigating and question-answer group (13 persons held 4 questioning sessions. Data were collected and analyzed by SPSS 17 using independent- and paired-T tests.  Findings: There were no significant differences between the average of CCTDI scores for problem-based learning group before (278.00±28.14 and after (309.29±13.80 the intervention and also between the average of CCTDI scores for question-answer group before (276.00±7.12 and after (306.62±16.32 the intervention (p>0.05. Both methods caused a significant increase in analytic power, information categorization and self-confidence of students (p<0.05.  Conclusion: Using both question-answer and problem-based educational methods can improve the attitude to critical thinking in students.

  13. Application of the “best representativity” method to a PWR fuel calculation using the critical experiments at the Toshiba NCA facility

    International Nuclear Information System (INIS)

    Umano, Takuya; Yoshioka, Kenichi; Obara, Toru

    2015-01-01

    Highlights: • Calculation procedures are easier than those of the cross-section adjustment method. • In addition, few cases of experimental results, two or three cases for example, can be well managed with the method. • Different from the bias factor method, a representativity factor is simultaneously obtained to know the whole quality of utilized experiments. • After easier process of calculations, it is possible to obtain a correction value of a particular physical property with the method. • Our proposed method was considered to be applicable to the correction of the infinite neutron multiplication factor in LWR studies. - Abstract: To judge the applicability of a critical experiment, it is necessary to confirm the similarities of the experiment with actual reactor conditions or equipment. The concept of the “representativity factor” has been well adopted since the late 1970’s, particularly for fast breeder reactors (FBRs) and future reactor studies. In our previous study, we extended this concept to the design of a light water reactor (LWR) system, and derived mathematical formulas for a new numerical evaluation method to correct a physical property of a target system. This method is different from the cross-section adjustment method and the bias factor method. For the first qualification of the method, sample calculations were carried out to correct the effective neutron multiplication factor through critical experiments at the Toshiba Nuclear Critical Assembly (NCA) facility. We also compared the result with that of the Product of Exponentiated experimental values method (PE method) of the extended bias factor methods. A good agreement was observed. The purpose of this study was to demonstrate the applicability of the method to the infinite neutron multiplication factor. Using the method and three kinds of critical experiments of NCA, calculations were performed to correct the infinite neutron multiplication factor of a pressurized water

  14. The role of multisensor data fusion in neuromuscular control of a sagittal arm with a pair of muscles using actor-critic reinforcement learning method.

    Science.gov (United States)

    Golkhou, V; Parnianpour, M; Lucas, C

    2004-01-01

    In this study, we consider the role of multisensor data fusion in neuromuscular control using an actor-critic reinforcement learning method. The model we use is a single link system actuated by a pair of muscles that are excited with alpha and gamma signals. Various physiological sensor information such as proprioception, spindle sensors, and Golgi tendon organs have been integrated to achieve an oscillatory movement with variable amplitude and frequency, while achieving a stable movement with minimum metabolic cost and coactivation. The system is highly nonlinear in all its physical and physiological attributes. Transmission delays are included in the afferent and efferent neural paths to account for a more accurate representation of the reflex loops. This paper proposes a reinforcement learning method with an Actor-Critic architecture instead of middle and low level of central nervous system (CNS). The Actor in this structure is a two layer feedforward neural network and the Critic is a model of the cerebellum. The Critic is trained by the State-Action-Reward-State-Action (SARSA) method. The Critic will train the Actor by supervisory learning based on previous experiences. The reinforcement signal in SARSA is evaluated based on available alternatives concerning the concept of multisensor data fusion. The effectiveness and the biological plausibility of the present model are demonstrated by several simulations. The system showed excellent tracking capability when we integrated the available sensor information. Addition of a penalty for activation of muscles resulted in much lower muscle coactivation while keeping the movement stable.

  15. Method for estimating critical properties of heavy compounds suitable for cubic equations of state and its application to the prediction of vapor pressures

    DEFF Research Database (Denmark)

    Kontogeorgis, Georgios; Ioannis, Smirlis; Iakovos, Yakoumis

    1997-01-01

    S. The proposed scheme employs a recent group-contribution method (Constantinou et al. Fluid Phase Equilib. 1995, 103 (1), 11) for estimating the acentric factor. The two critical properties are estimated via a generalized correlation for the ratio T-c/P-c (with the van der Waals surface area) and the cubic Eo...... pressures for several nonpolar and slightly polar heavy compounds with very satisfactory results, essentially independent of the experimental point used. Furthermore, the method yields critical properties for heavy alkanes (N-c > 20) and other compounds which are in very good agreement with recent available......Cubic equations of state (EoS) are often used for correlating and predicting phase equilibria. Before extending any EoS to mixtures, reliable vapor-pressure prediction is essential. This requires experimental, if possible, critical temperatures T-c, pressures P-c, and acentric factor omega...

  16. Study on burnup credit evaluation method at JAERI towards securing criticality safety rationale for management of spent fuel

    International Nuclear Information System (INIS)

    Nomura, Y.

    1998-01-01

    Lately, due to massive accumulation of spent fuel discharged from light water reactors in Japan, it is gradually demanded to introduce the so-called burnup credit methodology into criticality safety design for nuclear fuel cycle facilities, such as spent fuel storage pools and transport casks. In order to save space in the spent fuel storage pool of the Rokkasho Reprocessing Plant, the burnup credit design has been firstly implemented for its criticality safety evaluation. Here, its design conditions and operational control procedures are briefly shown and research using burned fuel at JAERI is explained to support its licensing safety review, focusing on the relevant content of the Nuclear Criticality Safety Handbook of Japan, which has been prepared so far and planned in the near future. Finally, international co-operation for study on burnup credit issues practiced by JAERI is addressed. (author)

  17. Exploring the Philosophical Underpinnings of Research: Relating Ontology and Epistemology to the Methodology and Methods of the Scientific, Interpretive, and Critical Research Paradigms

    Science.gov (United States)

    Scotland, James

    2012-01-01

    This paper explores the philosophical underpinnings of three major educational research paradigms: scientific, interpretive, and critical. The aim was to outline and explore the interrelationships between each paradigm's ontology, epistemology, methodology and methods. This paper reveals and then discusses some of the underlying assumptions of…

  18. Multi-Trait Multi-Method Matrices for the Validation of Creativity and Critical Thinking Assessments for Secondary School Students in England and Greece

    Directory of Open Access Journals (Sweden)

    Ourania Maria Ventista

    2017-08-01

    Full Text Available The aim of this paper is the validation of measurement tools which assess critical thinking and creativity as general constructs instead of subject-specific skills. Specifically, this research examined whether there is convergent and discriminant (or divergent validity between measurement tools of creativity and critical thinking. For this purpose, the multi-trait and multi-method matrix suggested by Campbell and Fiske (1959 was used. This matrix presented the correlation of scores that students obtain in different assessments in order to reveal whether the assessments measure the same or different constructs. Specifically, the two methods used were written and oral exams, and the two traits measured were critical thinking and creativity. For the validation of the assessments, 30 secondary-school students in Greece and 21 in England completed the assessments. The sample in both countries provided similar results. The critical thinking tools demonstrated convergent validity when compared with each other and discriminant validity with the creativity assessments. Furthermore, creativity assessments which measure the same aspect of creativity demonstrated convergent validity. To conclude, this research provided indicators that critical thinking and creativity as general constructs can be measured in a valid way. However, since the sample was small, further investigation of the validation of the assessment tools with a bigger sample is recommended.

  19. Classification of criticality calculations with correlation coefficient method and its application to OECD/NEA burnup credit benchmarks phase III-A and II-A

    International Nuclear Information System (INIS)

    Okuno, Hiroshi

    2003-01-01

    A method for classifying benchmark results of criticality calculations according to similarity was proposed in this paper. After formulation of the method utilizing correlation coefficients, it was applied to burnup credit criticality benchmarks Phase III-A and II-A, which were conducted by the Expert Group on Burnup Credit Criticality Safety under auspices of the Nuclear Energy Agency of the Organisation for Economic Cooperation and Development (OECD/NEA). Phase III-A benchmark was a series of criticality calculations for irradiated Boiling Water Reactor (BWR) fuel assemblies, whereas Phase II-A benchmark was a suite of criticality calculations for irradiated Pressurized Water Reactor (PWR) fuel pins. These benchmark problems and their results were summarized. The correlation coefficients were calculated and sets of benchmark calculation results were classified according to the criterion that the values of the correlation coefficients were no less than 0.15 for Phase III-A and 0.10 for Phase II-A benchmarks. When a couple of benchmark calculation results belonged to the same group, one calculation result was found predictable from the other. An example was shown for each of the Benchmarks. While the evaluated nuclear data seemed the main factor for the classification, further investigations were required for finding other factors. (author)

  20. Efficacy of teaching methods used to develop critical thinking in nursing and midwifery undergraduate students: A systematic review of the literature.

    Science.gov (United States)

    Carter, Amanda G; Creedy, Debra K; Sidebotham, Mary

    2016-05-01

    The value and importance of incorporating strategies that promote critical thinking in nursing and midwifery undergraduate programmes are well documented. However, relatively little is known about the effectiveness of teaching strategies in promoting CT. Evaluating effectiveness is important to promote 'best practise' in teaching. To evaluate the efficacy of teaching methods used to develop critical thinking skills in nursing and midwifery undergraduate students. The following six databases; CINAHL, Ovid Medline, ERIC, Informit, PsycINFO and Scopus were searched and resulted in the retrieval of 1315 papers. After screening for inclusion, each paper was evaluated using the Critical Appraisal Skills Programme tool. Twenty-eight studies met the inclusion criteria and quality appraisal. Twelve different teaching interventions were tested in 8 countries. Results varied, with little consistency across studies using the same type of intervention or outcome tool. Sixteen tools were used to measure the efficacy of teaching in developing critical thinking. Seventeen studies identified a significant increase in critical thinking, while nine studies found no increases, and two found unexplained decreases in CT when using a similar educational intervention. Whilst this review aimed to identify effective teaching strategies that promote and develop critical thinking, flaws in methodology and outcome measures contributed to inconsistent findings. The continued use of generalised CT tools is unlikely to help identify appropriate teaching methods that will improve CT abilities of midwifery and nursing students and prepare them for practise. The review was limited to empirical studies published in English that used measures of critical thinking with midwifery and nursing students. Discipline specific strategies and tools that measure students' abilities to apply CT in practise are needed. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  1. Soil processes and functions across an international network of critical zone observations: introduction to experimental methods and initial results

    NARCIS (Netherlands)

    Banwart, S.; Menon, M.; Bernasconi, S.M.; Bloem, J.; Ruiter, de P.C.; Weng, L.P.

    2012-01-01

    Growth in human population and demand for wealth creates ever-increasing pressure on global soils, leading to soil losses and degradation worldwide. Critical Zone science studies the impact linkages between these pressures, the resulting environmental state of soils, and potential interventions to

  2. Study by the Prandtl-Glauert method of compressibility effects and critical Mach number for ellipsoids of various aspect ratios and thickness ratios

    Science.gov (United States)

    Hess, Robert V; Gardner, Clifford S

    1947-01-01

    By using the Prandtl-Glauert method that is valid for three-dimensional flow problems, the value of the maximum incremental velocity for compressible flow about thin ellipsoids at zero angle of attack is calculated as a function of the Mach number for various aspect ratios and thickness ratios. The critical Mach numbers of the various ellipsoids are also determined. The results indicate an increase in critical Mach number with decrease in aspect ratio which is large enough to explain experimental results on low-aspect-ratio wings at zero lift.

  3. Method to increase the transition temperature and for the critical magnetic field strength of the known intermetallic compounds of vanadium or niobium

    International Nuclear Information System (INIS)

    Winter, H.

    1977-01-01

    The invention deals with a method to raise the transition temperature and critical magnetic field strength of superconducting, intermetallic compounds of vanadium and niobium. For example, a niobium alloy with 4 wt.% Al in melted in vacuum electric arc and formed into a sheet of about 1 mm thick. Strips of this sheet are electrically heated up to 1,900 0 C for one hour in a high-vacuum oven. The strips are then annealed in evacuated quartz ampoules for 120 hours at 800 0 C. These strips have a transition temperature of 24 K and a critical magnetic field strength of 600 kg; the critical current density was 5 x 10 4 A/cm 2 . (HPOE) [de

  4. A method for development of efficient 3D models for neutronic calculations of ASTRA critical facility using experimental information

    Energy Technology Data Exchange (ETDEWEB)

    Balanin, A. L.; Boyarinov, V. F.; Glushkov, E. S.; Zimin, A. A.; Kompaniets, G. V.; Nevinitsa, V. A., E-mail: Neviniza-VA@nrcki.ru; Moroz, N. P.; Fomichenko, P. A.; Timoshinov, A. V. [National Research Center Kurchatov Institute (Russian Federation); Volkov, Yu. N. [National Research Nuclear University MEPhI (Russian Federation)

    2016-12-15

    The application of experimental information on measured axial distributions of fission reaction rates for development of 3D numerical models of the ASTRA critical facility taking into account azimuthal asymmetry of the assembly simulating a HTGR with annular core is substantiated. Owing to the presence of the bottom reflector and the absence of the top reflector, the application of 2D models based on experimentally determined buckling is impossible for calculation of critical assemblies of the ASTRA facility; therefore, an alternative approach based on the application of the extrapolated assembly height is proposed. This approach is exemplified by the numerical analysis of experiments on measurement of efficiency of control rods mockups and protection system (CPS).

  5. A method for development of efficient 3D models for neutronic calculations of ASTRA critical facility using experimental information

    International Nuclear Information System (INIS)

    Balanin, A. L.; Boyarinov, V. F.; Glushkov, E. S.; Zimin, A. A.; Kompaniets, G. V.; Nevinitsa, V. A.; Moroz, N. P.; Fomichenko, P. A.; Timoshinov, A. V.; Volkov, Yu. N.

    2016-01-01

    The application of experimental information on measured axial distributions of fission reaction rates for development of 3D numerical models of the ASTRA critical facility taking into account azimuthal asymmetry of the assembly simulating a HTGR with annular core is substantiated. Owing to the presence of the bottom reflector and the absence of the top reflector, the application of 2D models based on experimentally determined buckling is impossible for calculation of critical assemblies of the ASTRA facility; therefore, an alternative approach based on the application of the extrapolated assembly height is proposed. This approach is exemplified by the numerical analysis of experiments on measurement of efficiency of control rods mockups and protection system (CPS).

  6. Integrating Theory, Content, and Method to Foster Critical Consciousness in Medical Students: A Comprehensive Model for Cultural Competence Training.

    Science.gov (United States)

    Dao, Diane K; Goss, Adeline L; Hoekzema, Andrew S; Kelly, Lauren A; Logan, Alexander A; Mehta, Sanjiv D; Sandesara, Utpal N; Munyikwa, Michelle R; DeLisser, Horace M

    2017-03-01

    Many efforts to design introductory "cultural competence" courses for medical students rely on an information delivery (competence) paradigm, which can exoticize patients while obscuring social context, medical culture, and power structures. Other approaches foster a general open-minded orientation, which can remain nebulous without clear grounding principles. Medical educators are increasingly recognizing the limitations of both approaches and calling for strategies that reenvision cultural competence training. Successfully realizing such alternative strategies requires the development of comprehensive models that specify and integrate theoretical frameworks, content, and teaching principles.In this article, the authors present one such model: Introduction to Medicine and Society (IMS), a required cultural competence course launched in 2013 for first-year medical students at the Perelman School of Medicine at the University of Pennsylvania. Building on critical pedagogy, IMS is centered on a novel specification of "critical consciousness" in clinical practice as an orientation to understanding and pragmatic action in three relational domains: internal, interpersonal, and structural. Instead of transmitting discrete "facts" about patient "types," IMS content provokes students to engage with complex questions bridging the three domains. Learning takes place in a small-group space specifically designed to spur transformation toward critical consciousness. After discussing the three key components of the course design and describing a representative session, the authors discuss the IMS model's implications, reception by students and faculty, and potential for expansion. Their early experience suggests the IMS model successfully engages students and prepares future physicians to critically examine experiences, manage interpersonal dynamics, and structurally contextualize patient encounters.

  7. Test of the core design methods for the THTR 300 with experimental results from the critical facility KAHTER

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, K.; Huebner, A.; Brandes, S.; Krings, F.

    1974-10-15

    At the Kernforschungsanlage Juelich, core physics experiments with core 1 and core 2 of the critical facility for high temperature reactors KAHTER were carried out in 1973. Core 2 corresponds to the THTR initial core in its moderation ratio S = 7500. Selected experimental results on the critical mass, on control rod worths, and reaction rate distributions were used for testing the most important procedures for the THTR core physics design. The zero-dimensional spectrum program MUPO with its cross section library and the and neutron flux calculations in two-dimensional diffusion approximation by CRAM are of central importance. It proved to be important to introduce modifications specific to the KAHTER plant into the standard models. Thus the void effect (void above the pebble bed) was investigated with DOT-2 by transport theory and a correction was introduced for the critical masses calculated by diffusion theory. Another feature already contained in the standard procedure, the increase of the diffusion constants for the hollow spaces between the spheres, results in a correction of 3.8% < delta-k for KAHTER, whereas in the THTR 300 it only amounts to several tenths % delta-k. Critical masses are predicted with accuracies of < 1.5 % or with regard to reactivity < 0.65 % delta-k. The calculated values for the radial neutron flux distributions deviate from the measured values in the core area by approximately lo %. In the case of the axial profiles, deviations are observed at the pebble bed surface which can be explained by the upper void, which cannot be satisfactorily represented by the diffusion theory. Control rod worths are predicted quite well, i.e., to within +/- 5%. An exception is the bank of 4 reflector rods, where the applied model of the "grey curtain" is not accurate because of the large distances between rods. The calculated control rod worths for that case were found to be too low, which does, however, not result in a safety problem.

  8. An Analytic Hierarchy Process-based Method to Rank the Critical Success Factors of Implementing a Pharmacy Barcode System.

    Science.gov (United States)

    Alharthi, Hana; Sultana, Nahid; Al-Amoudi, Amjaad; Basudan, Afrah

    2015-01-01

    Pharmacy barcode scanning is used to reduce errors during the medication dispensing process. However, this technology has rarely been used in hospital pharmacies in Saudi Arabia. This article describes the barriers to successful implementation of a barcode scanning system in Saudi Arabia. A literature review was conducted to identify the relevant critical success factors (CSFs) for a successful dispensing barcode system implementation. Twenty-eight pharmacists from a local hospital in Saudi Arabia were interviewed to obtain their perception of these CSFs. In this study, planning (process flow issues and training requirements), resistance (fear of change, communication issues, and negative perceptions about technology), and technology (software, hardware, and vendor support) were identified as the main barriers. The analytic hierarchy process (AHP), one of the most widely used tools for decision making in the presence of multiple criteria, was used to compare and rank these identified CSFs. The results of this study suggest that resistance barriers have a greater impact than planning and technology barriers. In particular, fear of change is the most critical factor, and training is the least critical factor.

  9. Curricular Innovation in the Surgery Clerkship: Can Assessment Methods Influence Development of Critical Thinking and Clinical Skills?

    Science.gov (United States)

    McClintic, James A; Snyder, Clifford L; Brown, Kimberly M

    2018-03-12

    Although key clinical skills have been defined in the Core Entrustable Professional Activities, there is a need to improve medical school curricula with standardized training opportunities and assessments of these skills. Thus, we aimed to develop an innovative curriculum that emphasized critical thinking and clinical skills. We hypothesized that we would be able to observe measurable improvement on assessments of students' critical thinking and clinical skills after the implementation of the new curriculum. Prospective, Quasi-Experimental study with the use of historical controls. This study took place through the third-year surgical clerkship at the University of Texas Medical Branch at the Galveston, Houston, and Austin, Texas, locations. A total of 214 students taking the third-year surgical clerkship for the first time during the periods of interest were included. Although the students with traditional curriculum improved 9.5% on a short answer exam from preclerkship to postclerkship completion, the students with new curriculum improved by 40%. Students under the new curriculum performed significantly better on the Objective Structured Clinical Exam; however, their shelf scores were lower. Under this new curriculum and grading system, we demonstrated that students can be incentivized to improve critical thinking and clinical skills, but this needs to be balanced with knowledge-based incentives. Copyright © 2018 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  10. Field, temperature, and angle dependent critical current density Jc(H,T,θ) in coated conductors obtained via contact-free methods

    International Nuclear Information System (INIS)

    Thompson, J R; Christen, D K; Zhang Yifei; Zuev, Y L; Cantoni, C; Sinclair, J W; Chen Yimin; Selvamanickam, V

    2010-01-01

    Applications of coated conductors based on high- T c superconductors often require detailed knowledge of their critical current density J c as a function of magnetic field orientation as well as field strength and temperature. This work demonstrates experimental methods for obtaining the angularly dependent J c using contact-free magnetic measurements, and qualifies those methods using several well defined conditions. The studies complement traditional transport techniques and are readily extended to conditions of field and temperature where the current density is very large and transport methods become difficult. Results on representative materials are presented.

  11. Field, temperature, and angle dependent critical current density Jc(H,T, ) in coated conductors obtained via contact-free methods

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, James R [ORNL; Sinclair IV, John W [ORNL; Christen, David K [ORNL; Zhang, Yifei [ORNL; Zuev, Yuri L [ORNL; Cantoni, Claudia [ORNL; Chen, Y [SuperPower Incorporated, Schenectady, New York; Selvamanickam, V. [SuperPower Incorporated, Schenectady, New York

    2010-01-01

    Applications of coated conductors based on high-Tc superconductors often require detailed knowledge of their critical current density Jc as a function of magnetic field orientation as well as field strength and temperature. This work demonstrates experimental methods to obtain the angularly dependent Jc using contact-free magnetic measurements, and qualifies those methods using several well defined conditions. The studies complement traditional transport techniques and are readily extended to conditions of field and temperature where the current density is very large and transport methods become difficult. Results on representative materials are presented.

  12. Field, temperature, and angle dependent critical current density J{sub c}(H,T,{theta}) in coated conductors obtained via contact-free methods

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, J R; Christen, D K; Zhang Yifei; Zuev, Y L; Cantoni, C [Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6092 (United States); Sinclair, J W [Department of Physics, University of Tennessee, Knoxville, TN 37996-1200 (United States); Chen Yimin; Selvamanickam, V [SuperPower, Incorporated, 450 Duane Avenue, Schenectady, NY 12304 (United States)

    2010-01-15

    Applications of coated conductors based on high- T{sub c} superconductors often require detailed knowledge of their critical current density J{sub c} as a function of magnetic field orientation as well as field strength and temperature. This work demonstrates experimental methods for obtaining the angularly dependent J{sub c} using contact-free magnetic measurements, and qualifies those methods using several well defined conditions. The studies complement traditional transport techniques and are readily extended to conditions of field and temperature where the current density is very large and transport methods become difficult. Results on representative materials are presented.

  13. Neuromuscular control of the point to point and oscillatory movements of a sagittal arm with the actor-critic reinforcement learning method.

    Science.gov (United States)

    Golkhou, Vahid; Parnianpour, Mohamad; Lucas, Caro

    2005-04-01

    In this study, we have used a single link system with a pair of muscles that are excited with alpha and gamma signals to achieve both point to point and oscillatory movements with variable amplitude and frequency.The system is highly nonlinear in all its physical and physiological attributes. The major physiological characteristics of this system are simultaneous activation of a pair of nonlinear muscle-like-actuators for control purposes, existence of nonlinear spindle-like sensors and Golgi tendon organ-like sensor, actions of gravity and external loading. Transmission delays are included in the afferent and efferent neural paths to account for a more accurate representation of the reflex loops.A reinforcement learning method with an actor-critic (AC) architecture instead of middle and low level of central nervous system (CNS), is used to track a desired trajectory. The actor in this structure is a two layer feedforward neural network and the critic is a model of the cerebellum. The critic is trained by state-action-reward-state-action (SARSA) method. The critic will train the actor by supervisory learning based on the prior experiences. Simulation studies of oscillatory movements based on the proposed algorithm demonstrate excellent tracking capability and after 280 epochs the RMS error for position and velocity profiles were 0.02, 0.04 rad and rad/s, respectively.

  14. Stochastic methods for the quantification of sensitivities and uncertainties in criticality analyses; Stochastische Methoden zur Quantifizierung von Sensitivitaeten und Unsicherheiten in Kritikalitaetsanalysen

    Energy Technology Data Exchange (ETDEWEB)

    Behler, Matthias; Bock, Matthias; Stuke, Maik; Wagner, Markus

    2014-06-15

    This work describes statistical analyses based on Monte Carlo sampling methods for criticality safety analyses. The methods analyse a large number of calculations of a given problem with statistically varied model parameters to determine uncertainties and sensitivities of the computed results. The GRS development SUnCISTT (Sensitivities and Uncertainties in Criticality Inventory and Source Term Tool) is a modular, easily extensible abstract interface program, designed to perform such Monte Carlo sampling based uncertainty and sensitivity analyses in the field of criticality safety. It couples different criticality and depletion codes commonly used in nuclear criticality safety assessments to the well-established GRS tool SUSA for sensitivity and uncertainty analyses. For uncertainty analyses of criticality calculations, SunCISTT couples various SCALE sequences developed at Oak Ridge National Laboratory and the general Monte Carlo N-particle transport code MCNP from Los Alamos National Laboratory to SUSA. The impact of manufacturing tolerances of a fuel assembly configuration on the neutron multiplication factor for the various sequences is shown. Uncertainties in nuclear inventories, dose rates, or decay heat can be investigated via the coupling of the GRS depletion system OREST to SUSA. Some results for a simplified irradiated Pressurized Water Reactor (PWR) UO{sub 2} fuel assembly are shown. SUnCISTT also combines the two aforementioned modules for burnup credit criticality analysis of spent nuclear fuel to ensures an uncertainty and sensitivity analysis using the variations of manufacturing tolerances in the burn-up code and criticality code simultaneously. Calculations and results for a storage cask loaded with typical irradiated PWR UO{sub 2} fuel are shown, including Monte Carlo sampled axial burn-up profiles. The application of SUnCISTT in the field of code validation, specifically, how it is applied to compare a simulation model to available benchmark

  15. Criticality calculations on pebble-bed HTR-PROTEUS configuration as a validation for the pseudo-scattering tracking method implemented in the MORET 5 Monte Carlo code

    Energy Technology Data Exchange (ETDEWEB)

    Forestier, Benoit; Miss, Joachim; Bernard, Franck; Dorval, Aurelien [Institut de Radioprotection et Surete Nucleaire, Fontenay aux Roses (France); Jacquet, Olivier [Independent consultant (France); Verboomen, Bernard [Belgian Nuclear Research Center - SCK-CEN (Belgium)

    2008-07-01

    The MORET code is a three dimensional Monte Carlo criticality code. It is designed to calculate the effective multiplication factor (k{sub eff}) of any geometrical configuration as well as the reaction rates in the various volumes and the neutron leakage out of the system. A recent development for the MORET code consists of the implementation of an alternate neutron tracking method, known as the pseudo-scattering tracking method. This method has been successfully implemented in the MORET code and its performances have been tested by mean of an extensive parametric study on very simple geometrical configurations. In this context, the goal of the present work is to validate the pseudo-scattering method against realistic configurations. In this perspective, pebble-bed cores are particularly well-adapted cases to model, as they exhibit large amount of volumes stochastically arranged on two different levels (the pebbles in the core and the TRISO particles inside each pebble). This paper will introduce the techniques and methods used to model pebble-bed cores in a realistic way. The results of the criticality calculations, as well as the pseudo-scattering tracking method performance in terms of computation time, will also be presented. (authors)

  16. Safety analysis of geologic containment of long life radioactive wastes. Critical assessment of existing methods and proposition of prospective approach

    International Nuclear Information System (INIS)

    Masure, P.; Gedefroy, P.; Imauven, C.

    1983-01-01

    Existing methods of risk analysis applied to disposal of long-lived radioactive waste in geologic formations are rewieved. A prospective analysis method for containment performances is proposed, deduced in the burial system from the combination of interaction between wastes, repository, host rock, surrounding geosphere, of natural evolution of each component of the system, sudden or chance events that could break waste containment. The method is based on the elaboration of four basic schemes graded in difficulties to facilitate comparisons

  17. A criticality safety analysis code using a vectorized Monte Carlo method on the HITAC S-810 supercomputer

    International Nuclear Information System (INIS)

    Morimoto, Y.; Maruyama, H.

    1987-01-01

    A vectorized Monte Carlo criticality safety analysis code has been developed on the vector supercomputer HITAC S-810. In this code, a multi-particle tracking algorithm was adopted for effective utilization of the vector processor. A flight analysis with pseudo-scattering was developed to reduce the computational time needed for flight analysis, which represents the bulk of computational time. This new algorithm realized a speed-up of factor 1.5 over the conventional flight analysis. The code also adopted the multigroup cross section constants library of the Bodarenko type with 190 groups, with 132 groups being for fast and epithermal regions and 58 groups being for the thermal region. Evaluation work showed that this code reproduce the experimental results to an accuracy of about 1 % for the effective neutron multiplication factor. (author)

  18. Validation of multigroup neutron cross sections and calculational methods for the advanced neutron source against the FOEHN critical experiments measurements

    International Nuclear Information System (INIS)

    Smith, L.A.; Gallmeier, F.X.; Gehin, J.C.

    1995-05-01

    The FOEHN critical experiment was analyzed to validate the use of multigroup cross sections and Oak Ridge National Laboratory neutronics computer codes in the design of the Advanced Neutron Source. The ANSL-V 99-group master cross section library was used for all the calculations. Three different critical configurations were evaluated using the multigroup KENO Monte Carlo transport code, the multigroup DORT discrete ordinates transport code, and the multigroup diffusion theory code VENTURE. The simple configuration consists of only the fuel and control elements with the heavy water reflector. The intermediate configuration includes boron endplates at the upper and lower edges of the fuel element. The complex configuration includes both the boron endplates and components in the reflector. Cross sections were processed using modules from the AMPX system. Both 99-group and 20-group cross sections were created and used in two-dimensional models of the FOEHN experiment. KENO calculations were performed using both 99-group and 20-group cross sections. The DORT and VENTURE calculations were performed using 20-group cross sections. Because the simple and intermediate configurations are azimuthally symmetric, these configurations can be explicitly modeled in R-Z geometry. Since the reflector components cannot be modeled explicitly using the current versions of these codes, three reflector component homogenization schemes were developed and evaluated for the complex configuration. Power density distributions were calculated with KENO using 99-group cross sections and with DORT and VENTURE using 20-group cross sections. The average differences between the measured values and the values calculated with the different computer codes range from 2.45 to 5.74%. The maximum differences between the measured and calculated thermal flux values for the simple and intermediate configurations are ∼ 13%, while the average differences are < 8%

  19. Determining the Critical Slip Surface of Three-Dimensional Soil Slopes from the Stress Fields Solved Using the Finite Element Method

    Directory of Open Access Journals (Sweden)

    Yu-chuan Yang

    2016-01-01

    Full Text Available The slope stability problem is an important issue for the safety of human beings and structures. The stability analysis of the three-dimensional (3D slope is essential to prevent landslides, but the most important and difficult problem is how to determine the 3D critical slip surface with the minimum factor of safety in earth slopes. Basing on the slope stress field with the finite element method, a stability analysis method is proposed to determine the critical slip surface and the corresponding safety factor of 3D soil slopes. Spherical and ellipsoidal slip surfaces are considered through the analysis. The moment equilibrium is used to compute the safety factor combined with the Mohr-Coulomb criteria and the limit equilibrium principle. Some assumptions are introduced to reduce the search range of center points and the radius of spheres or ellipsoids. The proposed method is validated by a classical 3D benchmark soil slope. Simulated results indicate that the safety factor of the benchmark slope is 2.14 using the spherical slip surface and 2.19 using the ellipsoidal slip surface, which is close to the results of previous methods. The simulated results indicate that the proposed method can be used for the stability analysis of a 3D soil slope.

  20. Life cycle tools combined with multi-criteria and participatory methods for agricultural sustainability: Insights from a systematic and critical review.

    Science.gov (United States)

    De Luca, Anna Irene; Iofrida, Nathalie; Leskinen, Pekka; Stillitano, Teodora; Falcone, Giacomo; Strano, Alfio; Gulisano, Giovanni

    2017-10-01

    Life cycle (LC) methodologies have attracted a great interest in agricultural sustainability assessments, even if, at the same time, they have sometimes been criticized for making unrealistic assumptions and subjective choices. To cope with these weaknesses, Multi-Criteria Decision Analysis (MCDA) and/or participatory methods can be used to balance and integrate different sustainability dimensions. The purpose of this study is to highlight how life cycle approaches were combined with MCDA and participatory methods to address agricultural sustainability in the published scientific literature. A systematic and critical review was developed, highlighting the following features: which multi-criterial and/or participatory methods have been associated with LC tools; how they have been integrated or complemented (methodological relationships); the intensity of the involvement of stakeholders (degree of participation); and which synergies have been achieved by combining the methods. The main typology of integration was represented by multi-criterial frameworks integrating LC evaluations. LC tools can provide MCDA studies with local and global information on how to reduce negative impacts and avoid burden shifts, while MCDA methods can help LC practitioners deal with subjective assumptions in an objective way, to take into consideration actors' values and to overcome trade-offs among the different dimensions of sustainability. Considerations concerning the further development of Life Cycle Sustainability Assessment (LCSA) have been identified as well. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Application of the single-channel continuous synthesis method to criticity and power distribution calculations in thermal reactors

    International Nuclear Information System (INIS)

    Medrano Asensio, Gregorio.

    1976-06-01

    A detailed power distribution calculation in a large power reactor requires the solution of the multigroup 3D diffusion equations. Using the finite difference method, this computation is too expensive to be performed for design purposes. This work is devoted to the single channel continous synthesis method: the choice of the trial functions and the determination of the mixing functions are discussed in details; 2D and 3D results are presented. The method is applied to the calculation of the IAEA ''Benchmark'' reactor and the results obtained are compared with a finite element resolution and with published results [fr

  2. On the suitability of fast and frugal heuristics for designing values clarification methods in patient decision aids : A critical analysis

    NARCIS (Netherlands)

    Pieterse, A.H.; de Vries, M.

    2013-01-01

    Background  Increasingly, patient decision aids and values clarification methods (VCMs) are being developed to support patients in making preference-sensitive health-care decisions. Many VCMs encourage extensive deliberation about options, without solid theoretical or empirical evidence showing that

  3. Methods and means for building a system of visual images forming in gis of critical important objects protection

    Directory of Open Access Journals (Sweden)

    Mykhailo Vasiukhin

    2013-12-01

    Full Text Available Requirements for the visualization of dynamic scenes in security systems for are increasing in recent years. This requires develop a methods and tools for visualization of dynamic scenes for monitoring and managing the system of security like “human-operator”. The paper presents a model map data from which is a base for building real time map data, and methods of real time visualization of moving characters in air.

  4. Solution of Large Systems of Linear Equations in the Presence of Errors. A Constructive Criticism of the Least Squares Method

    Energy Technology Data Exchange (ETDEWEB)

    Nygaard, K

    1968-09-15

    From the point of view that no mathematical method can ever minimise or alter errors already made in a physical measurement, the classical least squares method has severe limitations which makes it unsuitable for the statistical analysis of many physical measurements. Based on the assumptions that the experimental errors are characteristic for each single experiment and that the errors must be properly estimated rather than minimised, a new method for solving large systems of linear equations is developed. The new method exposes the entire range of possible solutions before the decision is taken which of the possible solutions should be chosen as a representative one. The choice is based on physical considerations which (in two examples, curve fitting and unfolding of a spectrum) are presented in such a form that a computer is able to make the decision, A description of the computation is given. The method described is a tool for removing uncertainties due to conventional mathematical formulations (zero determinant, linear dependence) and which are not inherent in the physical problem as such. The method is therefore especially well fitted for unfolding of spectra.

  5. Solution of Large Systems of Linear Equations in the Presence of Errors. A Constructive Criticism of the Least Squares Method

    International Nuclear Information System (INIS)

    Nygaard, K.

    1968-09-01

    From the point of view that no mathematical method can ever minimise or alter errors already made in a physical measurement, the classical least squares method has severe limitations which makes it unsuitable for the statistical analysis of many physical measurements. Based on the assumptions that the experimental errors are characteristic for each single experiment and that the errors must be properly estimated rather than minimised, a new method for solving large systems of linear equations is developed. The new method exposes the entire range of possible solutions before the decision is taken which of the possible solutions should be chosen as a representative one. The choice is based on physical considerations which (in two examples, curve fitting and unfolding of a spectrum) are presented in such a form that a computer is able to make the decision, A description of the computation is given. The method described is a tool for removing uncertainties due to conventional mathematical formulations (zero determinant, linear dependence) and which are not inherent in the physical problem as such. The method is therefore especially well fitted for unfolding of spectra

  6. Mixing it but not mixed-up: mixed methods research in medical education (a critical narrative review).

    Science.gov (United States)

    Maudsley, Gillian

    2011-01-01

    Some important research questions in medical education and health services research need 'mixed methods research' (particularly synthesizing quantitative and qualitative findings). The approach is not new, but should be more explicitly reported. The broad search question here, of a disjointed literature, was thus: What is mixed methods research - how should it relate to medical education research?, focused on explicit acknowledgement of 'mixing'. Literature searching focused on Web of Knowledge supplemented by other databases across disciplines. Five main messages emerged: - Thinking quantitative and qualitative, not quantitative versus qualitative - Appreciating that mixed methods research blends different knowledge claims, enquiry strategies, and methods - Using a 'horses for courses' [whatever works] approach to the question, and clarifying the mix - Appreciating how medical education research competes with the 'evidence-based' movement, health services research, and the 'RCT' - Being more explicit about the role of mixed methods in medical education research, and the required expertise Mixed methods research is valuable, yet the literature relevant to medical education is fragmented and poorly indexed. The required time, effort, expertise, and techniques deserve better recognition. More write-ups should explicitly discuss the 'mixing' (particularly of findings), rather than report separate components.

  7. Classical algorithms for automated parameter-search methods in compartmental neural models - A critical survey based on simulations using neuron

    International Nuclear Information System (INIS)

    Mutihac, R.; Mutihac, R.C.; Cicuttin, A.

    2001-09-01

    Parameter-search methods are problem-sensitive. All methods depend on some meta-parameters of their own, which must be determined experimentally in advance. A better choice of these intrinsic parameters for a certain parameter-search method may improve its performance. Moreover, there are various implementations of the same method, which may also affect its performance. The choice of the matching (error) function has a great impact on the search process in terms of finding the optimal parameter set and minimizing the computational cost. An initial assessment of the matching function ability to distinguish between good and bad models is recommended, before launching exhaustive computations. However, different runs of a parameter search method may result in the same optimal parameter set or in different parameter sets (the model is insufficiently constrained to accurately characterize the real system). Robustness of the parameter set is expressed by the extent to which small perturbations in the parameter values are not affecting the best solution. A parameter set that is not robust is unlikely to be physiologically relevant. Robustness can also be defined as the stability of the optimal parameter set to small variations of the inputs. When trying to estimate things like the minimum, or the least-squares optimal parameters of a nonlinear system, the existence of multiple local minima can cause problems with the determination of the global optimum. Techniques such as Newton's method, the Simplex method and Least-squares Linear Taylor Differential correction technique can be useful provided that one is lucky enough to start sufficiently close to the global minimum. All these methods suffer from the inability to distinguish a local minimum from a global one because they follow the local gradients towards the minimum, even if some methods are resetting the search direction when it is likely to get stuck in presumably a local minimum. Deterministic methods based on

  8. Critical review of real-time methods for solid waste characterisation: Informing material recovery and fuel production.

    Science.gov (United States)

    Vrancken, C; Longhurst, P J; Wagland, S T

    2017-03-01

    Waste management processes generally represent a significant loss of material, energy and economic resources, so legislation and financial incentives are being implemented to improve the recovery of these valuable resources whilst reducing contamination levels. Material recovery and waste derived fuels are potentially valuable options being pursued by industry, using mechanical and biological processes incorporating sensor and sorting technologies developed and optimised for recycling plants. In its current state, waste management presents similarities to other industries that could improve their efficiencies using process analytical technology tools. Existing sensor technologies could be used to measure critical waste characteristics, providing data required by existing legislation, potentially aiding waste treatment processes and assisting stakeholders in decision making. Optical technologies offer the most flexible solution to gather real-time information applicable to each of the waste mechanical and biological treatment processes used by industry. In particular, combinations of optical sensors in the visible and the near-infrared range from 800nm to 2500nm of the spectrum, and different mathematical techniques, are able to provide material information and fuel properties with typical performance levels between 80% and 90%. These sensors not only could be used to aid waste processes, but to provide most waste quality indicators required by existing legislation, whilst offering better tools to the stakeholders. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Thinking in clinical nursing practice: a study of critical care nurses' thinking applying the think-aloud, protocol analysis method.

    Science.gov (United States)

    Han, Kyung-Ja; Kim, Hesook Suzie; Kim, Mae-Ja; Hong, Kyung-Ja; Park, Sungae; Yun, Soon-Nyoung; Song, Misoon; Jung, Yoenyi; Kim, Haewon; Kim, Dong-Oak Debbie; Choi, Heejung; Kim, Kyungae

    2007-06-01

    The purpose of the paper is to discover the patterns and processes of decision-making in clinical nursing practice. A set of think-aloud data from five critical care nurses during 40 to 50 minutes of caregiving in intensive care units were obtained and analyzed by applying the procedures recommended by Ericsson and Simon for protocol analysis. Four thinking processes before acting were identified to constitute various sorts of thoughts in which the nurses were engaged during patient care: reviewing, validation, consideration, rationalization, and action. In addition, three patterns of sequential streaming of thinking (short, intermediate, long) were identified to reveal various ways the nurses dealt with clinical situations involving nursing tasks and responsibilities. This study specifies the initial categories of thoughts for each of the processes and various patterns with which these processes are sequentially combined, providing insights into the ways nurses think about problems and address their concerns. The findings suggest that the thinking in clinical practice involves more than focused decision-making and reasoning, and needs to be examined from a broader perspective.

  10. Nuclear criticality safety: general. 4. The CASTOR X/32S Method of Covering mis-loading Concerns

    International Nuclear Information System (INIS)

    Lancaster, Dale B.; Rombough, Charles T.; Diersch, Rudolf; Spilker, Harry

    2001-01-01

    In the United States, most cask licenses do not directly consider mis-loading. If the enrichment limit for a shipping cask is high and the reactivity control is inherent in the cask, the reactivity effect of a mis-load is small. However, in large-capacity casks, such as the CASTOR X/32S, the effect can be much larger. The U.S. Department of Energy Topical Report on Actinide- Only Burnup Credit takes the position that a fuel assembly mis-load does need to be analyzed since there are multiple independent checks, and thus, the double-contingency principle is met. Unfortunately, 11 assemblies were mis-loaded at Palisades. This event has caused the U.S. Nuclear Regulatory Commission (NRC) to ask for more detail on prevention of mis-loading. In the summer of 1999, Palisades loaded 11 assemblies, which did not comply with the loading requirements for their VSC-24 cask. The cask requires 5 yr of cooling, and these 11 assemblies had just a little more than 4 yr of cooling. The mis-loading did not result in an unsafe condition but in an un-reviewed condition. This mis-loading was not identified until November 2000 during a review related to an NRC information notice. The loading plan for the cask was incorrect. The engineering review of the loading plan missed the error. The operators had loaded the cask consistent with the loading plan. The cask loading was then confirmed by comparing to the loading plan. The loading plan was in error since the engineer assumed that the entire region of fuel was discharged at the same time. The 11 assemblies of concern were reinserted in the reactor, and the engineer and the reviewer did not check for this. The reactor records for all the assemblies were correct but apparently were not checked by the engineer who created the loading plan. To prevent a mis-load criticality event, the following steps will be required for the CASTOR X/32S storage and transport cask: 1. A loading plan will be prepared for each cask loaded. This plan will be

  11. Exploring genomic dark matter: A critical assessment of the performance of homology search methods on noncoding RNA

    DEFF Research Database (Denmark)

    Freyhult, E.; Bollback, J. P.; Gardner, P. P.

    2006-01-01

    Homology search is one of the most ubiquitous bioinformatic tasks, yet it is unknown how effective the currently available tools are for identifying noncoding RNAs (ncRNAs). In this work, we use reliable ncRNA data sets to assess the effectiveness of methods such as BLAST, FASTA, HMMer, and Infer......Homology search is one of the most ubiquitous bioinformatic tasks, yet it is unknown how effective the currently available tools are for identifying noncoding RNAs (ncRNAs). In this work, we use reliable ncRNA data sets to assess the effectiveness of methods such as BLAST, FASTA, HMMer......, and Infernal. Surprisingly, the most popular homology search methods are often the least accurate. As a result, many studies have used inappropriate tools for their analyses. On the basis of our results, we suggest homology search strategies using the currently available tools and some directions for future...

  12. CRITICAL DEVELOPMENT OF COSTING METHODS USED IN THE FURNITURE INDUSTRY, IN THE CONTEXT OF ECONOMIC REALITY SPECIAL XXI CENTURY

    Directory of Open Access Journals (Sweden)

    Ene Dumitru

    2010-12-01

    Full Text Available In the current economic downturn in the furniture industry companies, to face competition, requires new costing methods to succeed, in a flexible manner, fructifying market information, inside to find levers to identify places, resource intensive activities and then cost reduction opportunities. New methods of management cost excess the accounting and economics scope Current economic situation requires this work and converts the cost information into the main tool of insurance competitiveness and profitability of the company. Applying the standard cost in single cost model is a viable business solutions of enterprises in the furniture industry to face strong competition from European Union, specifically in the context of complex economic XXI century.

  13. A critical evaluation of deterministic methods in size optimisation of reliable and cost effective standalone hybrid renewable energy systems

    International Nuclear Information System (INIS)

    Maheri, Alireza

    2014-01-01

    Reliability of a hybrid renewable energy system (HRES) strongly depends on various uncertainties affecting the amount of power produced by the system. In the design of systems subject to uncertainties, both deterministic and nondeterministic design approaches can be adopted. In a deterministic design approach, the designer considers the presence of uncertainties and incorporates them indirectly into the design by applying safety factors. It is assumed that, by employing suitable safety factors and considering worst-case-scenarios, reliable systems can be designed. In fact, the multi-objective optimisation problem with two objectives of reliability and cost is reduced to a single-objective optimisation problem with the objective of cost only. In this paper the competence of deterministic design methods in size optimisation of reliable standalone wind–PV–battery, wind–PV–diesel and wind–PV–battery–diesel configurations is examined. For each configuration, first, using different values of safety factors, the optimal size of the system components which minimises the system cost is found deterministically. Then, for each case, using a Monte Carlo simulation, the effect of safety factors on the reliability and the cost are investigated. In performing reliability analysis, several reliability measures, namely, unmet load, blackout durations (total, maximum and average) and mean time between failures are considered. It is shown that the traditional methods of considering the effect of uncertainties in deterministic designs such as design for an autonomy period and employing safety factors have either little or unpredictable impact on the actual reliability of the designed wind–PV–battery configuration. In the case of wind–PV–diesel and wind–PV–battery–diesel configurations it is shown that, while using a high-enough margin of safety in sizing diesel generator leads to reliable systems, the optimum value for this margin of safety leading to a

  14. Thinking Critically about Critical Thinking

    Science.gov (United States)

    Mulnix, Jennifer Wilson

    2012-01-01

    As a philosophy professor, one of my central goals is to teach students to think critically. However, one difficulty with determining whether critical thinking can be taught, or even measured, is that there is widespread disagreement over what critical thinking actually is. Here, I reflect on several conceptions of critical thinking, subjecting…

  15. Critical comparison of radiometric and mass spectrometric methods for the determination of radionuclides in environmental, biological and nuclear waste samples

    DEFF Research Database (Denmark)

    Hou, Xiaolin; Roos, Per

    2008-01-01

    application in the environmental and biological researches, these radionuclides include H-3, C-14, Cl-36, Ca-41 Ni-59,Ni-63, Sr-89,Sr-90, Tc-99, I-129, Cs-135,Cs-137, Pb-210, Ra-226,Ra-228, Np-237, Am-241, and isotopes of thorium, uranium and plutonium. The application of on-line methods (flow injection...

  16. Effects of Three Diagram Instruction Methods on Transfer of Diagram Comprehension Skills: The Critical Role of Inference While Learning

    Science.gov (United States)

    Cromley, Jennifer G.; Bergey, Bradley W.; Fitzhugh, Shannon; Newcombe, Nora; Wills, Theodore W.; Shipley, Thomas F.; Tanaka, Jacqueline C.

    2013-01-01

    Can students be taught to better comprehend the diagrams in their textbooks? Can such teaching transfer to uninstructed diagrams in the same domain or even in a new domain? What methods work best for these goals? Building on previous research showing positive results compared to control groups in both laboratory studies and short-term…

  17. The critical assessment of vapour pressure estimation methods for use in modelling the formation of atmospheric organic aerosol

    Directory of Open Access Journals (Sweden)

    M. H. Barley

    2010-01-01

    Full Text Available A selection of models for estimating vapour pressures have been tested against experimental data for a set of compounds selected for their particular relevance to the formation of atmospheric aerosol by gas-liquid partitioning. The experimental vapour pressure data (all <100 Pa of 45 multifunctional compounds provide a stringent test of the estimation techniques, with a recent complex group contribution method providing the best overall results. The effect of errors in vapour pressures upon the formation of organic aerosol by gas-liquid partitioning in an atmospherically relevant example is also investigated. The mass of organic aerosol formed under typical atmospheric conditions was found to be very sensitive to the variation in vapour pressure values typically present when comparing estimation methods.

  18. [Reconsidering children's dreams. A critical review of methods and results in developmental dream research from Freud to contemporary works].

    Science.gov (United States)

    Sándor, Piroska; Bódizs, Róbert

    2014-01-01

    Examining children's dream development is a significant challenge for researchers. Results from studies on children's dreaming may enlighten us on the nature and role of dreaming as well as broaden our knowledge of consciousness and cognitive development. This review summarizes the main questions and historical progress in developmental dream research, with the aim of shedding light on the advantages, disadvantages and effects of different settings and methods on research outcomes. A typical example would be the dreams of 3 to 5 year-olds: they are simple and static, with a relative absence of emotions and active self participation according to laboratory studies; studies using different methodology however found them to be vivid, rich in emotions, with the self as an active participant. Questions about the validity of different methods arise, and are considered within this review. Given that methodological differences can result in highly divergent outcomes, it is strongly recommended for future research to select methodology and treat results more carefully.

  19. Critical analysis of stability and performance of organometal halide perovskite solar cells via various fabrication method (Review

    Directory of Open Access Journals (Sweden)

    Suhaimi Suriati

    2017-01-01

    Full Text Available Organometal halide perovskite solar cells (Omh-PSCs have attracted attention due to its unique electrical and optical properties. Ideally, the Omh-PSCs should remain free from degradation under normal operating conditions for several years, preferably tens of years. In order to produce high power conversion efficiency with low potential of degradation, different fabrication methods have been developed. The reported stability of perovskite films can vary significantly and reported to decay substantially up to 20% of its original performance. A thorough understanding of fabrication process upon the stability of the device is regarded as crucial to pave the way for future endeavors. This review summarized and highlighted the recent research of fabrication methods that gave an impact to the stability of perovskite devices.

  20. Criticality handbook. Pt. 1

    International Nuclear Information System (INIS)

    Heinicke, W.; Krug, H.; Thomas, W.; Weber, W.; Gmal, B.

    1985-12-01

    The GRS Criticality Handbook is intended as a source of information on criticality problems for the persons concerned in industry, authorities, or research laboratories. It is to serve as a guide allowing quick and appropriate evaluation of criticality problems during design or erection of nuclear installations. This present issue replaces the one published in 1979, presenting revised and new data in a modified construction, but within the framework of the proven basic structure of the Handbook. Some fundamental knowledge is required of criticality problems and the relevant terms and definitions of nuclear safety, in order to fully deploy the information given. Part 1 of the Handbook therefore first introduces terminology and definitions, followed by experimental methods and calculation models for criticality calculations. The next chapters deal with the function and efficiency of neutron reflectors and neutron absorbers, measuring methods for criticality monitoring, organisational safety measures, and criticality accidents and their subsequent analysis. (orig./HP) [de

  1. Determination of bromine in selected polymer materials by a wavelength-dispersive X-ray fluorescence spectrometric method - Critical thickness problem and solutions

    Science.gov (United States)

    Gorewoda, Tadeusz; Mzyk, Zofia; Anyszkiewicz, Jacek; Charasińska, Jadwiga

    2015-04-01

    The purpose of this study was to develop an accurate method for the determination of bromine in polymer materials using X-ray fluorescence spectrometry when the thickness of the sample is less than the bromine critical thickness (tc) value. This is particularly important for analyzing compliance with the Restriction of Hazardous Substances Directive. Mathematically and experimentally estimated tc values in polyethylene and cellulose matrixes were up to several millimeters. Four methods were developed to obtain an accurate result. These methods include the addition of an element with a high mass absorption coefficient, the measurement of the total bromine contained in a defined volume of the sample, the exploitation of tube-Rayleigh line intensities and using the Br-Lβ line.

  2. A critical appraisal of the zero-multipole method: Structural, thermodynamic, dielectric, and dynamical properties of a water system

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Han, E-mail: wang-han@iapcm.ac.cn [CAEP Software Center for High Performance Numerical Simulation, Huayuan Road 6, 100088 Beijing, China and Zuse Institute Berlin (ZIB), Berlin (Germany); Nakamura, Haruki [Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); Fukuda, Ikuo, E-mail: ifukuda@protein.osaka-u.ac.jp [Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871 (Japan); RIKEN (The Institute of Physical and Chemical Research), 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)

    2016-03-21

    We performed extensive and strict tests for the reliability of the zero-multipole (summation) method (ZMM), which is a method for estimating the electrostatic interactions among charged particles in a classical physical system, by investigating a set of various physical quantities. This set covers a broad range of water properties, including the thermodynamic properties (pressure, excess chemical potential, constant volume/pressure heat capacity, isothermal compressibility, and thermal expansion coefficient), dielectric properties (dielectric constant and Kirkwood-G factor), dynamical properties (diffusion constant and viscosity), and the structural property (radial distribution function). We selected a bulk water system, the most important solvent, and applied the widely used TIP3P model to this test. In result, the ZMM works well for almost all cases, compared with the smooth particle mesh Ewald (SPME) method that was carefully optimized. In particular, at cut-off radius of 1.2 nm, the recommended choices of ZMM parameters for the TIP3P system are α ≤ 1 nm{sup −1} for the splitting parameter and l = 2 or l = 3 for the order of the multipole moment. We discussed the origin of the deviations of the ZMM and found that they are intimately related to the deviations of the equilibrated densities between the ZMM and SPME, while the magnitude of the density deviations is very small.

  3. A critical appraisal of the zero-multipole method: Structural, thermodynamic, dielectric, and dynamical properties of a water system.

    Science.gov (United States)

    Wang, Han; Nakamura, Haruki; Fukuda, Ikuo

    2016-03-21

    We performed extensive and strict tests for the reliability of the zero-multipole (summation) method (ZMM), which is a method for estimating the electrostatic interactions among charged particles in a classical physical system, by investigating a set of various physical quantities. This set covers a broad range of water properties, including the thermodynamic properties (pressure, excess chemical potential, constant volume/pressure heat capacity, isothermal compressibility, and thermal expansion coefficient), dielectric properties (dielectric constant and Kirkwood-G factor), dynamical properties (diffusion constant and viscosity), and the structural property (radial distribution function). We selected a bulk water system, the most important solvent, and applied the widely used TIP3P model to this test. In result, the ZMM works well for almost all cases, compared with the smooth particle mesh Ewald (SPME) method that was carefully optimized. In particular, at cut-off radius of 1.2 nm, the recommended choices of ZMM parameters for the TIP3P system are α ≤ 1 nm(-1) for the splitting parameter and l = 2 or l = 3 for the order of the multipole moment. We discussed the origin of the deviations of the ZMM and found that they are intimately related to the deviations of the equilibrated densities between the ZMM and SPME, while the magnitude of the density deviations is very small.

  4. Optimization of the Critical Parameters of the Spherical Agglomeration Crystallization Method by the Application of the Quality by Design Approach

    Directory of Open Access Journals (Sweden)

    Orsolya Gyulai

    2018-04-01

    Full Text Available This research work presents the use of the Quality by Design (QbD concept for optimization of the spherical agglomeration crystallization method in the case of the active agent, ambroxol hydrochloride (AMB HCl. AMB HCl spherical crystals were formulated by the spherical agglomeration method, which was applied as an antisolvent technique. Spherical crystals have good flowing properties, which makes the direct compression tableting method applicable. This means that the amount of additives used can be reduced and smaller tablets can be formed. For the risk assessment, LeanQbD Software was used. According to its results, four independent variables (mixing type and time, dT (temperature difference between solvent and antisolvent, and composition (solvent/antisolvent volume ratio and three dependent variables (mean particle size, aspect ratio, and roundness were selected. Based on these, a 2–3 mixed-level factorial design was constructed, crystallization was accomplished, and the results were evaluated using Statistica for Windows 13 program. Product assay was performed and it was revealed that improvements in the mean particle size (from ~13 to ~200 µm, roundness (from ~2.4 to ~1.5, aspect ratio (from ~1.7 to ~1.4, and flow properties were observed while polymorphic transitions were avoided.

  5. Application of advanced surface and volumetric NDE methods to the detection of cracks in critical regions of turbine blades

    International Nuclear Information System (INIS)

    Porter, J.P.

    1990-01-01

    Advanced NDE inspection techniques capable of detecting small, yet potentially dangerous cracks in turbine blade tenons, blade tie-wire through-holes, trailing edges, and blade root attachment ends have been devised and developed and are now being applied successfully in the field replacing conventional, less-sensitive methods commonly used for crack detection in these blade elements. Under-shroud lateral cracks in tenons are detected ultrasonically by highangle refracted pulse-echo shear wave and 0-degree pitch-catch longitudinal wave methods. Trailing-edge blade cracks and surface-connected cracks in root attachment ends are detected by high frequency eddy current techniques, typically applied remotely using ports in the turbine housing to gain access to the parts under inspection. Cracks emanating from tie-wire holes in blade upper ends are detected by eddy current inspection, which has been found to be a far more effective methods than either magnetic particle or ultrasonic testing for this application. Root attachment ends of side entry blades are inspected volumetrically by ultrasonics, using proprietary coupling techniques that allow examination of heretofore uninspectable regions of blade attachment hooks, known regions of crack initiation. Techniques developed for this collection of applications are described, and the results of actual field inspections are presented and discussed

  6. SCIENTIFIC METHODOLOGY FOR THE APPLIED SOCIAL SCIENCES: CRITICAL ANALYSES ABOUT RESEARCH METHODS, TYPOLOGIES AND CONTRIBUTIONS FROM MARX, WEBER AND DURKHEIM

    Directory of Open Access Journals (Sweden)

    Mauricio Corrêa da Silva

    2015-06-01

    Full Text Available This study aims to discuss the importance of the scientific method to conduct and advertise research in applied social sciences and research typologies, as well as to highlight contributions from Marx, Weber and Durkheim to the scientific methodology. To reach this objective, we conducted a review of the literature on the term research, the scientific method,the research techniques and the scientific methodologies. The results of the investigation revealed that it is fundamental that the academic investigator uses a scientific method to conduct and advertise his/her academic works in applied social sciences in comparison with the biochemical or computer sciences and in the indicated literature. Regarding the contributions to the scientific methodology, we have Marx, dialogued, the dialectical, striking analysis, explicative of social phenomenon, the need to understand the phenomena as historical and concrete totalities; Weber, the distinction between “facts” and “value judgments” to provide objectivity to the social sciences and Durkheim, the need to conceptualize very well its object of study, reject sensible data and imbue with the spirit of discovery and of being surprised with the results.

  7. Optimization of the Critical Parameters of the Spherical Agglomeration Crystallization Method by the Application of the Quality by Design Approach.

    Science.gov (United States)

    Gyulai, Orsolya; Kovács, Anita; Sovány, Tamás; Csóka, Ildikó; Aigner, Zoltán

    2018-04-20

    This research work presents the use of the Quality by Design (QbD) concept for optimization of the spherical agglomeration crystallization method in the case of the active agent, ambroxol hydrochloride (AMB HCl). AMB HCl spherical crystals were formulated by the spherical agglomeration method, which was applied as an antisolvent technique. Spherical crystals have good flowing properties, which makes the direct compression tableting method applicable. This means that the amount of additives used can be reduced and smaller tablets can be formed. For the risk assessment, LeanQbD Software was used. According to its results, four independent variables (mixing type and time, dT (temperature difference between solvent and antisolvent), and composition (solvent/antisolvent volume ratio)) and three dependent variables (mean particle size, aspect ratio, and roundness) were selected. Based on these, a 2⁻3 mixed-level factorial design was constructed, crystallization was accomplished, and the results were evaluated using Statistica for Windows 13 program. Product assay was performed and it was revealed that improvements in the mean particle size (from ~13 to ~200 µm), roundness (from ~2.4 to ~1.5), aspect ratio (from ~1.7 to ~1.4), and flow properties were observed while polymorphic transitions were avoided.

  8. Assessing the human health impacts of exposure to disinfection by-products--a critical review of concepts and methods.

    Science.gov (United States)

    Grellier, James; Rushton, Lesley; Briggs, David J; Nieuwenhuijsen, Mark J

    2015-05-01

    Understanding the public health implications of chemical contamination of drinking water is important for societies and their decision-makers. The possible population health impacts associated with exposure to disinfection by-products (DBPs) are of particular interest due to their potential carcinogenicity and their widespread occurrence as a result of treatments employed to control waterborne infectious disease. We searched the literature for studies that have attempted quantitatively to assess population health impacts and health risks associated with exposure to DBPs in drinking water. We summarised and evaluated these assessments in terms of their objectives, methods, treatment of uncertainties, and interpretation and communication of results. In total we identified 40 studies matching our search criteria. The vast majority of studies presented estimates of generic cancer and non-cancer risks based on toxicological data and methods that were designed with regulatory, health-protective purposes in mind, and therefore presented imprecise and biased estimates of health impacts. Many studies insufficiently addressed the numerous challenges to DBP risk assessment, failing to evaluate the evidence for a causal relationship, not appropriately addressing the complex nature of DBP occurrence as a mixture of chemicals, not adequately characterising exposure in space and time, not defining specific health outcomes, not accounting for characteristics of target populations, and not balancing potential risks of DBPs against the health benefits related with drinking water disinfection. Uncertainties were often poorly explained or insufficiently accounted for, and important limitations of data and methods frequently not discussed. Grave conceptual and methodological limitations in study design, as well as erroneous use of available dose-response data, seriously impede the extent to which many of these assessments contribute to understanding the public health implications of

  9. Application of Finite Element Method to Analyze the Influences of Process Parameters on the Cut Surface in Fine Blanking Processes by Using Clearance-Dependent Critical Fracture Criteria

    Directory of Open Access Journals (Sweden)

    Phyo Wai Myint

    2018-04-01

    Full Text Available The correct choice of process parameters is important in predicting the cut surface and obtaining a fully-fine sheared surface in the fine blanking process. The researchers used the value of the critical fracture criterion obtained by long duration experiments to predict the conditions of cut surfaces in the fine blanking process. In this study, the clearance-dependent critical ductile fracture criteria obtained by the Cockcroft-Latham and Oyane criteria were used to reduce the time and cost of experiments to obtain the value of the critical fracture criterion. The Finite Element Method (FEM was applied to fine blanking processes to study the influences of process parameters such as the initial compression, the punch and die corner radii and the shape and size of the V-ring indenter on the length of the sheared surface. The effects of stress triaxiality and punch diameters on the cut surface produced by the fine blanking process are also discussed. The verified process parameters and tool geometry for obtaining a fully-fine sheared SPCC surface are described. The results showed that the accurate and stable prediction of ductile fracture initiation can be achieved using the Oyane criterion.

  10. A mixed-methods systematic review protocol to examine the use of physical restraint with critically ill adults and strategies for minimizing their use

    Directory of Open Access Journals (Sweden)

    Louise Rose

    2016-11-01

    Full Text Available Abstract Background Critically ill patients frequently experience severe agitation placing them at risk of harm. Physical restraint is common in intensive care units (ICUs for clinician concerns about safety. However, physical restraint may not prevent medical device removal and has been associated with negative physical and psychological consequences. While professional society guidelines, legislation, and accreditation standards recommend physical restraint minimization, guidelines for critically ill patients are over a decade old, with recommendations that are non-specific. Our systematic review will synthesize evidence on physical restraint in critically ill adults with the primary objective of identifying effective minimization strategies. Methods Two authors will independently search from inception to July 2016 the following: Ovid MEDLINE, CINAHL, Embase, Web of Science, Cochrane Library, PROSPERO, Joanna Briggs Institute, grey literature, professional society websites, and the International Clinical Trials Registry Platform. We will include quantitative and qualitative study designs, clinical practice guidelines, policy documents, and professional society recommendations relevant to physical restraint of critically ill adults. Authors will independently perform data extraction in duplicate and complete risk of bias and quality assessment using recommended tools. We will assess evidence quality for quantitative studies using the Grading of Recommendations Assessment, Development and Evaluation (GRADE approach and for qualitative studies using the Confidence in the Evidence from Reviews of Qualitative Research (CERQual guidelines. Outcomes of interest include (1 efficacy/effectiveness of physical restraint minimization strategies; (2 adverse events (unintentional device removal, psychological impact, physical injury and associated benefits including harm prevention; (3 ICU outcomes (ventilation duration, length of stay, and mortality; (4

  11. Discussion on the environmental protection acceptance method and the critical issues of the completion of projects about radiation usage in the hospitals

    International Nuclear Information System (INIS)

    Wang Wei

    2014-01-01

    It is widely used in the world that the hospitals take advantages of radiation technology. Practically it is involved radioactive isotope, sealed source and the usage of ray device. Based on the environmental protection acceptance of the finished projects, this article is aimed at the actual characteristics of the medical practice and differentiating the major factors of environmental effects, choosing the monitoring criteria and method of environmental protection acceptance and exploring the critical issues in the course of acceptance. Finally this essay is intended to provide theory evidence and technical support in the acceptance of the above projects. (author)

  12. Critical Care

    Science.gov (United States)

    Critical care helps people with life-threatening injuries and illnesses. It might treat problems such as complications from surgery, ... attention by a team of specially-trained health care providers. Critical care usually takes place in an ...

  13. Critical review of the methods for monitoring of lithium-ion batteries in electric and hybrid vehicles

    Science.gov (United States)

    Waag, Wladislaw; Fleischer, Christian; Sauer, Dirk Uwe

    2014-07-01

    Lithium-ion battery packs in hybrid and pure electric vehicles are always equipped with a battery management system (BMS). The BMS consists of hardware and software for battery management including, among others, algorithms determining battery states. The continuous determination of battery states during operation is called battery monitoring. In this paper, the methods for monitoring of the battery state of charge, capacity, impedance parameters, available power, state of health, and remaining useful life are reviewed with the focus on elaboration of their strengths and weaknesses for the use in on-line BMS applications. To this end, more than 350 sources including scientific and technical literature are studied and the respective approaches are classified in various groups.

  14. Validation of LWR calculation methods and JEF-1 based data libraries by TRX and BAPL critical experiments

    International Nuclear Information System (INIS)

    Pelloni, S.; Grimm, P.; Mathews, D.; Paratte, J.M.

    1989-06-01

    In this report the capability of various code systems widely used at PSI (such as WIMS-D, BOXER, and the AARE modules TRAMIX and MICROX-2 in connection with the one-dimensional transport code ONEDANT) and JEF-1 based nuclear data libraries to compute LWR lattices is analysed by comparing results from thermal reactor benchmarks TRX and BAPL with experiment and with previously published values. It is shown that with the JEF-1 evaluation eigenvalues are generally well predicted within 8 mk (1 mk = 0.001) or less by all code systems, and that all methods give reasonable results for the measured reaction rate within or not too far from the experimental uncertainty. This is consistent with previous similar studies. (author) 7 tabs., 36 refs

  15. Method and apparatus for forming high-critical-temperature superconducting layers on flat and/or elongated substrates

    Science.gov (United States)

    Ciszek, Theodore F.

    1994-01-01

    An elongated, flexible superconductive wire or strip is fabricated by pulling it through and out of a melt of metal oxide material at a rate conducive to forming a crystalline coating of superconductive metal oxide material on an elongated, flexible substrate wire or strip. A coating of crystalline superconductive material, such as Bi.sub.2 Sr.sub.2 CaCu.sub.2 O.sub.8, is annealed to effect conductive contact between adjacent crystalline structures in the coating material, which is then cooled to room temperature. The container for the melt can accommodate continuous passage of the substrate through the melt. Also, a second pass-through container can be used to simultaneously anneal and overcoat the superconductive coating with a hot metallic material, such as silver or silver alloy. A hollow, elongated tube casting method of forming an elongated, flexible superconductive wire includes drawing the melt by differential pressure into a heated tubular substrate.

  16. Using the integral equations method to model a 2G racetrack coil with anisotropic critical current dependence

    Science.gov (United States)

    Martins, F. G. R.; Sass, F.; Barusco, P.; Ferreira, A. C.; de Andrade, R., Jr.

    2017-11-01

    Second-generation (2G) superconducting wires have already proved their potential in several applications. These materials have a highly nonlinear behavior that turns an optimized engineering project into a challenge. Between several numerical techniques that can be used to perform this task, the integral equations (IE) method stands out for avoiding mesh problems by representing the 2G wire cross-sectional area by a line. While most applications need to be represented in a 3D geometry, the IE is limited to longitudinal or axisymmetric models. This work demonstrates that a complex 3D geometry can be modeled by several coupled simulations using the IE method. In order to prove this statement, the proposed technique was used to simulate a 2G racetrack coil considering the self-field magnitude (B) and incidence angle (θ) on the tape. The J c characteristic was modeled in terms of parallel and normal to the tape plane magnetic field components (J c(B ∥ , B ⊥)) obtained from a V-I(B, θ) characterization of a tape segment. This result was implemented using commercial software with both A-V (vector magnetic potential and scalar voltage potential) and IE coupled simulations solved by finite elements. This solution bypasses the meshing problem due to the tapes slim geometry, considering each turn a single 1D model, all magnetically interacting in two 2D models. The simulations results are in good agreement to what was both expected and observed in the literature. The simulation is compared to the measured V-I characteristic for a single pancake racetrack coil built with same geometry as its simulation models, and a theoretical study demonstrates the possibilities of the proposed tool for analyzing a racetrack coil current density and electric field behavior in each of its turns.

  17. Empirical studies on informal patient payments for health care services: a systematic and critical review of research methods and instruments

    Directory of Open Access Journals (Sweden)

    Pavlova Milena

    2010-09-01

    Full Text Available Abstract Background Empirical evidence demonstrates that informal patient payments are an important feature of many health care systems. However, the study of these payments is a challenging task because of their potentially illegal and sensitive nature. The aim of this paper is to provide a systematic review and analysis of key methodological difficulties in measuring informal patient payments. Methods The systematic review was based on the following eligibility criteria: English language publications that reported on empirical studies measuring informal patient payments. There were no limitations with regard to the year of publication. The content of the publications was analysed qualitatively and the results were organised in the form of tables. Data sources were Econlit, Econpapers, Medline, PubMed, ScienceDirect, SocINDEX. Results Informal payments for health care services are most often investigated in studies involving patients or the general public, but providers and officials are also sample units in some studies. The majority of the studies apply a single mode of data collection that involves either face-to-face interviews or group discussions. One of the main methodological difficulties reported in the publication concerns the inability of some respondents to distinguish between official and unofficial payments. Another complication is associated with the refusal of some respondents to answer questions on informal patient payments. We do not exclude the possibility that we have missed studies that reported in non-English language journals as well as very recent studies that are not yet published. Conclusions Given the recent evidence from research on survey methods, a self-administrated questionnaire during a face-to-face interview could be a suitable mode of collecting sensitive data, such as data on informal patient payments.

  18. Computational methods for predicting the response of critical as-built infrastructure to dynamic loads (architectural surety)

    Energy Technology Data Exchange (ETDEWEB)

    Preece, D.S.; Weatherby, J.R.; Attaway, S.W.; Swegle, J.W.; Matalucci, R.V.

    1998-06-01

    Coupled blast-structural computational simulations using supercomputer capabilities will significantly advance the understanding of how complex structures respond under dynamic loads caused by explosives and earthquakes, an understanding with application to the surety of both federal and nonfederal buildings. Simulation of the effects of explosives on structures is a challenge because the explosive response can best be simulated using Eulerian computational techniques and structural behavior is best modeled using Lagrangian methods. Due to the different methodologies of the two computational techniques and code architecture requirements, they are usually implemented in different computer programs. Explosive and structure modeling in two different codes make it difficult or next to impossible to do coupled explosive/structure interaction simulations. Sandia National Laboratories has developed two techniques for solving this problem. The first is called Smoothed Particle Hydrodynamics (SPH), a relatively new gridless method comparable to Eulerian, that is especially suited for treating liquids and gases such as those produced by an explosive. The SPH capability has been fully implemented into the transient dynamics finite element (Lagrangian) codes PRONTO-2D and -3D. A PRONTO-3D/SPH simulation of the effect of a blast on a protective-wall barrier is presented in this paper. The second technique employed at Sandia National Laboratories uses a relatively new code called ALEGRA which is an ALE (Arbitrary Lagrangian-Eulerian) wave code with specific emphasis on large deformation and shock propagation. ALEGRA is capable of solving many shock-wave physics problems but it is especially suited for modeling problems involving the interaction of decoupled explosives with structures.

  19. Seismic resistance evaluation methods for foundation ground of nuclear power plant and for critical civil engineering structures

    International Nuclear Information System (INIS)

    1985-01-01

    The Ground Integrity Subcommittee was established in September, 1979, in the Japan Society of Civil Engineers to systematize the relation among the survey, test, analysis, evaluation, design and construction of diverse geological features and grounds. The results were put in order in March, 1984. In this paper, the main results of examination by the Aseismatic Design Working Group consisted of three groups are reported. It was decided to evaluate the aseismatic capability of the foundation ground and surrounding slopes of reactor buildings and important outdoor structures so that the function of supporting buildings and installations is not impaired, and that influence is not exerted on the maintenance of the function of buildings and installations. The basic concept, design earthquake force and standard values for the evaluation of the aseismatic stability of the foundation ground and surrounding slopes of reactor buildings are described. The basic concept and the comparison of various methods of aseismatic calculation are reported regarding the evaluation of the aseismatic stability of important outdoor structures in civil engineering field. (Kako, I.)

  20. Four-channel asymmetric Real-Time PCR hybridization probe assay: a rapid pre-screening method for critical BCR-ABL kinase domain mutations.

    Science.gov (United States)

    Martinez-Serra, Jordi; Gutiérrez, Antonio; Marcús, Toni F; Soverini, Simona; Amat, Juan Carlos; Navarro-Palou, María; Ros, Teresa; Bex, Teresa; Ballester, Carmen; Bauça, Josep Miquel; SanFelix, Sara; Novo, Andrés; Vidal, Carmen; Santos, Carmen; Besalduch, Joan

    2012-03-01

    Within the laboratory protocols, used for the study of BCR-ABL resistance mutations in chronic myeloid leukemia patients treated with Imatinib, direct sequencing remains the reference method. Since the incidence of patients with a mutation-related loss of response is not very high, it is very useful in the routine laboratory to perform a fast pre-screening method. With this in mind, we have designed a new technique, based on a single Real-Time FRET-based PCR, followed by a study of melting peaks. This new tool, developed in a LightCycler 2.0, combines four different fluorescence channels for the simultaneous detection, in a single close tube, of critical mutations within the ABL kinase domain. Assay evaluation performed on 33 samples, previously genotyped by sequentiation, resulted in full concordance of results. This new methodology detects in a few steps the presence of critical mutations associated to Imatinib resistance. Copyright © 2012 Elsevier Inc. All rights reserved.