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Sample records for experience curve approach

  1. Analyzing price and efficiency dynamics of large appliances with the experience curve approach

    International Nuclear Information System (INIS)

    Weiss, Martin; Patel, Martin K.; Junginger, Martin; Blok, Kornelis

    2010-01-01

    Large appliances are major power consumers in households of industrialized countries. Although their energy efficiency has been increasing substantially in past decades, still additional energy efficiency potentials exist. Energy policy that aims at realizing these potentials faces, however, growing concerns about possible adverse effects on commodity prices. Here, we address these concerns by applying the experience curve approach to analyze long-term price and energy efficiency trends of three wet appliances (washing machines, laundry dryers, and dishwashers) and two cold appliances (refrigerators and freezers). We identify a robust long-term decline in both specific price and specific energy consumption of large appliances. Specific prices of wet appliances decline at learning rates (LR) of 29±8% and thereby much faster than those of cold appliances (LR of 9±4%). Our results demonstrate that technological learning leads to substantial price decline, thus indicating that the introduction of novel and initially expensive energy efficiency technologies does not necessarily imply adverse price effects in the long term. By extending the conventional experience curve approach, we find a steady decline in the specific energy consumption of wet appliances (LR of 20-35%) and cold appliances (LR of 13-17%). Our analysis suggests that energy policy might be able to bend down energy experience curves. (author)

  2. Understanding the reductions in US corn ethanol production costs: An experience curve approach

    International Nuclear Information System (INIS)

    Hettinga, W.G.; Junginger, H.M.; Dekker, S.C.; Hoogwijk, M.; McAloon, A.J.; Hicks, K.B.

    2009-01-01

    The US is currently the world's largest ethanol producer. An increasing percentage is used as transportation fuel, but debates continue on its costs competitiveness and energy balance. In this study, technological development of ethanol production and resulting cost reductions are investigated by using the experience curve approach, scrutinizing costs of dry grind ethanol production over the timeframe 1980-2005. Cost reductions are differentiated between feedstock (corn) production and industrial (ethanol) processing. Corn production costs in the US have declined by 62% over 30 years, down to 100$ 2005 /tonne in 2005, while corn production volumes almost doubled since 1975. A progress ratio (PR) of 0.55 is calculated indicating a 45% cost decline over each doubling in cumulative production. Higher corn yields and increasing farm sizes are the most important drivers behind this cost decline. Industrial processing costs of ethanol have declined by 45% since 1983, to below 130$ 2005 /m 3 in 2005 (excluding costs for corn and capital), equivalent to a PR of 0.87. Total ethanol production costs (including capital and net corn costs) have declined approximately 60% from 800$ 2005 /m 3 in the early 1980s, to 300$ 2005 /m 3 in 2005. Higher ethanol yields, lower energy use and the replacement of beverage alcohol-based production technologies have mostly contributed to this substantial cost decline. In addition, the average size of dry grind ethanol plants increased by 235% since 1990. For the future it is estimated that solely due to technological learning, production costs of ethanol may decline 28-44%, though this excludes effects of the current rising corn and fossil fuel costs. It is also concluded that experience curves are a valuable tool to describe both past and potential future cost reductions in US corn-based ethanol production

  3. Single-centre experience of retroperitoneoscopic approach in urology with tips to overcome the steep learning curve

    Directory of Open Access Journals (Sweden)

    Aneesh Srivastava

    2016-01-01

    Full Text Available Context: The retroperitoneoscopic or retroperitoneal (RP surgical approach has not become as popular as the transperitoneal (TP one due to the steeper learning curve. Aims: Our single-institution experience focuses on the feasibility, advantages and complications of retroperitoneoscopic surgeries (RS performed over the past 10 years. Tips and tricks have been discussed to overcome the steep learning curve and these are emphasised. Settings and Design: This study made a retrospective analysis of computerised hospital data of patients who underwent RP urological procedures from 2003 to 2013 at a tertiary care centre. Patients and Methods: Between 2003 and 2013, 314 cases of RS were performed for various urological procedures. We analysed the operative time, peri-operative complications, time to return of bowel sound, length of hospital stay, and advantages and difficulties involved. Post-operative complications were stratified into five grades using modified Clavien classification (MCC. Results: RS were successfully completed in 95.5% of patients, with 4% of the procedures electively performed by the combined approach (both RP and TP; 3.2% required open conversion and 1.3% were converted to the TP approach. The most common cause for conversion was bleeding. Mean hospital stay was 3.2 ± 1.2 days and the mean time for returning of bowel sounds was 16.5 ± 5.4 h. Of the patients, 1.4% required peri-operative blood transfusion. A total of 16 patients (5% had post-operative complications and the majority were grades I and II as per MCC. The rates of intra-operative and post-operative complications depended on the difficulty of the procedure, but the complications diminished over the years with the increasing experience of surgeons. Conclusion: Retroperitoneoscopy has proven an excellent approach, with certain advantages. The tips and tricks that have been provided and emphasised should definitely help to minimise the steep learning curve.

  4. Novel hybrid (magnet plus curve grasper) technique during transumbilical cholecystectomy: initial experience of a promising approach.

    Science.gov (United States)

    Millan, Carolina; Bignon, Horacion; Bellia, Gaston; Buela, Enrique; Rabinovich, Fernando; Albertal, Mariano; Martinez Ferro, Marcelo

    2013-10-01

    The use of magnets in transumbilical cholecystectomy (TUC) improves triangulation and achieves an optimal critical view. Nonetheless, the tendency of the magnets to collide hinders the process. In order to simplify the surgical technique, we developed a hybrid model with a single magnet and a curved grasper. All TUCs performed with a hybrid strategy in our pediatric population between September 2009 and July 2012 were retrospectively reviewed. Of 260 surgical procedures in which at least one magnet was used, 87 were TUCs. Of those, 62 were hybrid: 33 in adults and 29 in pediatric patients. The technique combines a magnet and a curved grasper. Through a transumbilical incision, we placed a 12-mm trocar and another flexible 5-mm trocar. The laparoscope with the working channel used the 12-mm trocar. The magnetic grasper was introduced to the abdominal cavity using the working channel to provide cephalic retraction of the gallbladder fundus. Across the flexible trocar, the assistant manipulated the curved grasper to mobilize the infundibulum. The surgeon operated through the working channel of the laparoscope. In this pediatric population, the mean age was 14 years (range, 4-17 years), and mean weight was 50 kg (range, 18-90 kg); 65% were girls. Mean operative time was 62 minutes. All procedures achieved a critical view of safety with no instrumental collision. There were no intraoperative or postoperative complications. The hospital stay was 1.4±0.6 days, and the median follow-up was 201 days. A hybrid technique, combining magnets and a curved grasper, simplifies transumbilical surgery. It seems feasible and safe for TUC and potentially reproducible.

  5. Global experience curves for wind farms

    International Nuclear Information System (INIS)

    Junginger, M.; Faaij, A.; Turkenburg, W.C.

    2005-01-01

    In order to forecast the technological development and cost of wind turbines and the production costs of wind electricity, frequent use is made of the so-called experience curve concept. Experience curves of wind turbines are generally based on data describing the development of national markets, which cause a number of problems when applied for global assessments. To analyze global wind energy price development more adequately, we compose a global experience curve. First, underlying factors for past and potential future price reductions of wind turbines are analyzed. Also possible implications and pitfalls when applying the experience curve methodology are assessed. Second, we present and discuss a new approach of establishing a global experience curve and thus a global progress ratio for the investment cost of wind farms. Results show that global progress ratios for wind farms may lie between 77% and 85% (with an average of 81%), which is significantly more optimistic than progress ratios applied in most current scenario studies and integrated assessment models. While the findings are based on a limited amount of data, they may indicate faster price reduction opportunities than so far assumed. With this global experience curve we aim to improve the reliability of describing the speed with which global costs of wind power may decline

  6. Investigation of learning and experience curves

    Energy Technology Data Exchange (ETDEWEB)

    Krawiec, F.; Thornton, J.; Edesess, M.

    1980-04-01

    The applicability of learning and experience curves for predicting future costs of solar technologies is assessed, and the major test case is the production economics of heliostats. Alternative methods for estimating cost reductions in systems manufacture are discussed, and procedures for using learning and experience curves to predict costs are outlined. Because adequate production data often do not exist, production histories of analogous products/processes are analyzed and learning and aggregated cost curves for these surrogates estimated. If the surrogate learning curves apply, they can be used to estimate solar technology costs. The steps involved in generating these cost estimates are given. Second-generation glass-steel and inflated-bubble heliostat design concepts, developed by MDAC and GE, respectively, are described; a costing scenario for 25,000 units/yr is detailed; surrogates for cost analysis are chosen; learning and aggregate cost curves are estimated; and aggregate cost curves for the GE and MDAC designs are estimated. However, an approach that combines a neoclassical production function with a learning-by-doing hypothesis is needed to yield a cost relation compatible with the historical learning curve and the traditional cost function of economic theory.

  7. Incorporating Experience Curves in Appliance Standards Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Garbesi, Karina; Chan, Peter; Greenblatt, Jeffery; Kantner, Colleen; Lekov, Alex; Meyers, Stephen; Rosenquist, Gregory; Buskirk, Robert Van; Yang, Hung-Chia; Desroches, Louis-Benoit

    2011-10-31

    The technical analyses in support of U.S. energy conservation standards for residential appliances and commercial equipment have typically assumed that manufacturing costs and retail prices remain constant during the projected 30-year analysis period. There is, however, considerable evidence that this assumption does not reflect real market prices. Costs and prices generally fall in relation to cumulative production, a phenomenon known as experience and modeled by a fairly robust empirical experience curve. Using price data from the Bureau of Labor Statistics, and shipment data obtained as part of the standards analysis process, we present U.S. experience curves for room air conditioners, clothes dryers, central air conditioners, furnaces, and refrigerators and freezers. These allow us to develop more representative appliance price projections than the assumption-based approach of constant prices. These experience curves were incorporated into recent energy conservation standards for these products. The impact on the national modeling can be significant, often increasing the net present value of potential standard levels in the analysis. In some cases a previously cost-negative potential standard level demonstrates a benefit when incorporating experience. These results imply that past energy conservation standards analyses may have undervalued the economic benefits of potential standard levels.

  8. Incorporating experience curves in appliance standards analysis

    International Nuclear Information System (INIS)

    Desroches, Louis-Benoit; Garbesi, Karina; Kantner, Colleen; Van Buskirk, Robert; Yang, Hung-Chia

    2013-01-01

    There exists considerable evidence that manufacturing costs and consumer prices of residential appliances have decreased in real terms over the last several decades. This phenomenon is generally attributable to manufacturing efficiency gained with cumulative experience producing a certain good, and is modeled by an empirical experience curve. The technical analyses conducted in support of U.S. energy conservation standards for residential appliances and commercial equipment have, until recently, assumed that manufacturing costs and retail prices remain constant during the projected 30-year analysis period. This assumption does not reflect real market price dynamics. Using price data from the Bureau of Labor Statistics, we present U.S. experience curves for room air conditioners, clothes dryers, central air conditioners, furnaces, and refrigerators and freezers. These experience curves were incorporated into recent energy conservation standards analyses for these products. Including experience curves increases the national consumer net present value of potential standard levels. In some cases a potential standard level exhibits a net benefit when considering experience, whereas without experience it exhibits a net cost. These results highlight the importance of modeling more representative market prices. - Highlights: ► Past appliance standards analyses have assumed constant equipment prices. ► There is considerable evidence of consistent real price declines. ► We incorporate experience curves for several large appliances into the analysis. ► The revised analyses demonstrate larger net present values of potential standards. ► The results imply that past standards analyses may have undervalued benefits.

  9. PV experience curves for the Netherlands

    International Nuclear Information System (INIS)

    Gerwig, R.

    2005-01-01

    Experience curves are one of several tools used by policy makers to take a look at market development. Numerous curves have been constructed for PV but none specific to the Netherlands. The objective of this report is to take a look at the price development of grid-connected PV systems in the Netherlands using the experience curve theory. After a literature and internet search and attempts to acquire information from PV companies information on 51% of the totally installed capacity was found. Curves for the period 1991-2001 were constructed based on system price, BOS (balance-of-system) price and inverter price. The progress ratio of the locally learning BOS was similar to the globally learning module market. This indicates that the pace of development of the Dutch PV market is similar to the globally followed pace. Improvement of the detail of the data might help to get a better idea of which BOS components have declined most. The similar progress ratio also shows the importance of investing both in module and system research as is the case in the Netherlands

  10. Melting curve of materials: theory versus experiments

    International Nuclear Information System (INIS)

    Alfe, D; Vocadlo, L; Price, G D; Gillan, M J

    2004-01-01

    A number of melting curves of various materials have recently been measured experimentally and calculated theoretically, but the agreement between different groups is not always good. We discuss here some of the problems which may arise in both experiments and theory. We also report the melting curves of Fe and Al calculated recently using quantum mechanics techniques, based on density functional theory with generalized gradient approximations. For Al our results are in very good agreement with both low pressure diamond-anvil-cell experiments (Boehler and Ross 1997 Earth Planet. Sci. Lett. 153 223, Haenstroem and Lazor 2000 J. Alloys Compounds 305 209) and high pressure shock wave experiments (Shaner et al 1984 High Pressure in Science and Technology ed Homan et al (Amsterdam: North-Holland) p 137). For Fe our results agree with the shock wave experiments of Brown and McQueen (1986 J. Geophys. Res. 91 7485) and Nguyen and Holmes (2000 AIP Shock Compression of Condensed Matter 505 81) and the recent diamond-anvil-cell experiments of Shen et al (1998 Geophys. Res. Lett. 25 373). Our results are at variance with the recent calculations of Laio et al (2000 Science 287 1027) and, to a lesser extent, with the calculations of Belonoshko et al (2000 Phys. Rev. Lett. 84 3638). The reasons for these disagreements are discussed

  11. The role of experience curves for setting MEPS for appliances

    International Nuclear Information System (INIS)

    Siderius, Hans-Paul

    2013-01-01

    Minimum efficiency performance standards (MEPS) are an important policy instrument to raise the efficiency of products. In most schemes the concept of life cycle costs (LCC) is used to guide setting the MEPS levels. Although a large body of literature shows that product cost is decreasing with increasing cumulative production, the experience curve, this is currently not used for setting MEPS. This article shows how to integrate the concept of the experience curve into LCC calculations for setting MEPS in the European Union and applies this to household laundry driers, refrigerator-freezers and televisions. The results indicate that for driers and refrigerator-freezers at least twice the energy savings compared to the current approach can be achieved. These products also show that energy label classes can successfully be used for setting MEPS. For televisions an experience curve is provided, showing a learning rate of 29%. However, television prices do not show a relation with energy efficiency but are to a large extent determined by the time the product is placed on the market. This suggests to policy makers that for televisions and other products with a short (re)design and market cycle timing is more important than the MEPS levels itself. - Highlights: • We integrate experience curves into life cycle cost calculations for MEPS. • For driers and refrigerators this results in at least twice the energy savings. • For flat panel televisions an experience curve is provided

  12. An approach to averaging digitized plantagram curves.

    Science.gov (United States)

    Hawes, M R; Heinemeyer, R; Sovak, D; Tory, B

    1994-07-01

    The averaging of outline shapes of the human foot for the purposes of determining information concerning foot shape and dimension within the context of comfort of fit of sport shoes is approached as a mathematical problem. An outline of the human footprint is obtained by standard procedures and the curvature is traced with a Hewlett Packard Digitizer. The paper describes the determination of an alignment axis, the identification of two ray centres and the division of the total curve into two overlapping arcs. Each arc is divided by equiangular rays which intersect chords between digitized points describing the arc. The radial distance of each ray is averaged within groups of foot lengths which vary by +/- 2.25 mm (approximately equal to 1/2 shoe size). The method has been used to determine average plantar curves in a study of 1197 North American males (Hawes and Sovak 1993).

  13. Experience Curves: A Tool for Energy Policy Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Neij, Lena; Helby, Peter [Lund Univ. (Sweden). Environmental and Energy Systems Studies; Dannemand Andersen, Per; Morthorst, Poul Erik [Riso National Laboratory, Roskilde (Denmark); Durstewitz, Michael; Hoppe-Kilpper, Martin [Inst. fuer Solare Energieversorgungstechnik e.V., Kassel (DE); and others

    2003-07-01

    The objective of the project, Experience curves: a tool for energy policy assessment (EXTOOL), was to analyse the experience curve as a tool for the assessment of energy policy measures. This is of special interest, since the use of experience curves for the assessment of energy policy measures requires the development of the established experience curve methodology. This development raises several questions which have been addressed and analysed in this project. The analysis is based on case studies of wind power, an area with considerable experience in technology development, deployment and policy measures. Therefore, a case study based on wind power provides a good opportunity to study the usefulness of experience curves as a tool for the assessment of energy policy measures. However, the results are discussed in terms of using experience curves for the assessment of any energy technology. The project shows that experience curves can be used to assess the effect of combined policy measures in terms of cost reductions. Moreover, the result of the project show that experience curves could be used to analyse international 'learning systems', i.e. cost reductions brought about by the development of wind power and policy measures used in other countries. Nevertheless, the use of experience curves for the assessment of policy programmes has several limitations. First, the analysis and assessment of policy programmes cannot be achieved unless relevant experience curves based on good data can be developed. The authors are of the opinion that only studies that provide evidence of the validity, reliability and relevance of experience curves should be taken into account in policy making. Second, experience curves provide an aggregated picture of the situation and more detailed analysis of various sources of cost reduction, and cost reductions resulting from individual policy measures, requires additional data and analysis tools. Third, we do not recommend the use of

  14. Dose-response curve estimation: a semiparametric mixture approach.

    Science.gov (United States)

    Yuan, Ying; Yin, Guosheng

    2011-12-01

    In the estimation of a dose-response curve, parametric models are straightforward and efficient but subject to model misspecifications; nonparametric methods are robust but less efficient. As a compromise, we propose a semiparametric approach that combines the advantages of parametric and nonparametric curve estimates. In a mixture form, our estimator takes a weighted average of the parametric and nonparametric curve estimates, in which a higher weight is assigned to the estimate with a better model fit. When the parametric model assumption holds, the semiparametric curve estimate converges to the parametric estimate and thus achieves high efficiency; when the parametric model is misspecified, the semiparametric estimate converges to the nonparametric estimate and remains consistent. We also consider an adaptive weighting scheme to allow the weight to vary according to the local fit of the models. We conduct extensive simulation studies to investigate the performance of the proposed methods and illustrate them with two real examples. © 2011, The International Biometric Society.

  15. Introducing errors in progress ratios determined from experience curves

    NARCIS (Netherlands)

    van Sark, W.G.J.H.M.

    2008-01-01

    Progress ratios (PRs) derived from historical data in experience curves are used for forecasting development of many technologies as a means to model endogenous technical change in for instance climate–economy models. These forecasts are highly sensitive to uncertainties in the progress ratio. As a

  16. Effect of driving experience on anticipatory look-ahead fixations in real curve driving.

    Science.gov (United States)

    Lehtonen, Esko; Lappi, Otto; Koirikivi, Iivo; Summala, Heikki

    2014-09-01

    Anticipatory skills are a potential factor for novice drivers' curve accidents. Behavioural data show that steering and speed regulation are affected by forward planning of the trajectory. When approaching a curve, the relevant visual information for online steering control and for planning is located at different eccentricities, creating a need to disengage the gaze from the guidance of steering to anticipatory look-ahead fixations over curves. With experience, peripheral vision can be increasingly used in the visual guidance of steering. This could leave experienced drivers more gaze time to invest on look-ahead fixations over curves, facilitating the trajectory planning. Eighteen drivers (nine novices, nine experienced) drove an instrumented vehicle on a rural road four times in both directions. Their eye movements were analyzed in six curves. The trajectory of the car was modelled and divided to approach, entry and exit phases. Experienced drivers spent less time on the road-ahead and more time on the look-ahead fixations over the curves. Look-ahead fixations were also more common in the approach than in the entry phase of the curve. The results suggest that with experience drivers allocate greater part of their visual attention to trajectory planning. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Putting experience curves in context : links to and between technology development, market diffusion, learning mechanisms and systems innovation theory

    NARCIS (Netherlands)

    Junginger, M.; Suurs, R.; Verbong, G.P.J.; Schaeffer, G.J.; Sark, W. van; Faaij, A. xx

    2010-01-01

    As far as the experience curve approach goes, the focus is mainly on quantifying the cost reductions of the technological artefact (e.g. a wind turbine or biomass power plant) due to technological development. However, the experience curve by itself offers no explanation why costs should decline in

  18. Comparing Angular and Curved Shapes in Terms of Implicit Associations and Approach/Avoidance Responses.

    Directory of Open Access Journals (Sweden)

    Letizia Palumbo

    Full Text Available Most people prefer smoothly curved shapes over more angular shapes. We investigated the origin of this effect using abstract shapes and implicit measures of semantic association and preference. In Experiment 1 we used a multidimensional Implicit Association Test (IAT to verify the strength of the association of curved and angular polygons with danger (safe vs. danger words, valence (positive vs. negative words and gender (female vs. male names. Results showed that curved polygons were associated with safe and positive concepts and with female names, whereas angular polygons were associated with danger and negative concepts and with male names. Experiment 2 used a different implicit measure, which avoided any need to categorise the stimuli. Using a revised version of the Stimulus Response Compatibility (SRC task we tested with a stick figure (i.e., the manikin approach and avoidance reactions to curved and angular polygons. We found that RTs for approaching vs. avoiding angular polygons did not differ, even in the condition where the angles were more pronounced. By contrast participants were faster and more accurate when moving the manikin towards curved shapes. Experiment 2 suggests that preference for curvature cannot derive entirely from an association of angles with threat. We conclude that smoothly curved contours make these abstract shapes more pleasant. Further studies are needed to clarify the nature of such a preference.

  19. Retrospective North American CFL Experience Curve Analysis and Correlation to Deployment Programs

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Sarah J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wei, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sohn, Michael D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-07-01

    Retrospective experience curves are a useful tool for understanding historic technology development, and can contribute to investment program analysis and future cost estimation efforts. This work documents our development of an analysis approach for deriving retrospective experience curves with a variable learning rate, and its application to develop an experience curve for compact fluorescent lamps for the global and North American markets over the years 1990-2007. Uncertainties and assumptions involved in interpreting data for our experience curve development are discussed, including the processing and transformation of empirical data, the selection of system boundaries, and the identification of historical changes in the learning rate over the course of 15 years. In the results that follow, we find that that the learning rate has changed at least once from 1990-2007. We also explore if, and to what degree, public deployment programs may have contributed to an increased technology learning rate in North America. We observe correlations between the changes in the learning rate and the initiation of new policies, abrupt technological advances, including improvements to ballast technology, and economic and political events such as trade tariffs and electricity prices. Finally, we discuss how the findings of this work (1) support the use of segmented experience curves for retrospective and prospective analysis and (2) may imply that investments in technological research and development have contributed to a change in market adoption and penetration.

  20. Generalized Wigner functions in curved spaces: A new approach

    International Nuclear Information System (INIS)

    Kandrup, H.E.

    1988-01-01

    It is well known that, given a quantum field in Minkowski space, one can define Wigner functions f/sub W//sup N/(x 1 ,p 1 ,...,x/sub N/,p/sub N/) which (a) are convenient to analyze since, unlike the field itself, they are c-number quantities and (b) can be interpreted in a limited sense as ''quantum distribution functions.'' Recently, Winter and Calzetta, Habib and Hu have shown one way in which these flat-space Wigner functions can be generalized to a curved-space setting, deriving thereby approximate kinetic equations which make sense ''quasilocally'' for ''short-wavelength modes.'' This paper suggests a completely orthogonal approach for defining curved-space Wigner functions which generalizes instead an object such as the Fourier-transformed f/sub W/ 1 (k,p), which is effectively a two-point function viewed in terms of the ''natural'' creation and annihilation operators a/sup dagger/(p-(12k) and a(p+(12k). The approach suggested here lacks the precise phase-space interpretation implicit in the approach of Winter or Calzetta, Habib, and Hu, but it is useful in that (a) it is geared to handle any ''natural'' mode decomposition, so that (b) it can facilitate exact calculations at least in certain limits, such as for a source-free linear field in a static spacetime

  1. Comparison of ductile-to-brittle transition curve fitting approaches

    International Nuclear Information System (INIS)

    Cao, L.W.; Wu, S.J.; Flewitt, P.E.J.

    2012-01-01

    Ductile-to-brittle transition (DBT) curve fitting approaches are compared over the transition temperature range for reactor pressure vessel steels with different kinds of data, including Charpy-V notch impact energy data and fracture toughness data. Three DBT curve fitting methods have been frequently used in the past, including the Burr S-Weibull and tanh distributions. In general there is greater scatter associated with test data obtained within the transition region. Therefore these methods give results with different accuracies, especially when fitting to small quantities of data. The comparison shows that the Burr distribution and tanh distribution can almost equally fit well distributed and large data sets extending across the test temperature range to include the upper and lower shelves. The S-Weibull distribution fit is poor for the lower shelf of the DBT curve. Overall for both large and small quantities of measured data the Burr distribution provides the best description. - Highlights: ► Burr distribution offers a better fit than that of a S-Weibull and tanh fit. ► Burr and tanh methods show similar fitting ability for a large data set. ► Burr method can fit sparse data well distributed across the test temperature. ► S-Weibull method cannot fit the lower shelf well and show poor fitting quality.

  2. a new approach of Analysing GRB light curves

    International Nuclear Information System (INIS)

    Varga, B.; Horvath, I.

    2005-01-01

    We estimated the T xx quantiles of the cumulative GRB light curves using our recalculated background. The basic information of the light curves was extracted by multivariate statistical methods. The possible classes of the light curves are also briefly discussed

  3. Master sintering curve: A practical approach to its construction

    Directory of Open Access Journals (Sweden)

    Pouchly V.

    2010-01-01

    Full Text Available The concept of a Master Sintering Curve (MSC is a strong tool for optimizing the sintering process. However, constructing the MSC from sintering data involves complicated and time-consuming calculations. A practical method for the construction of a MSC is presented in the paper. With the help of a few dilatometric sintering experiments the newly developed software calculates the MSC and finds the optimal activation energy of a given material. The software, which also enables sintering prediction, was verified by sintering tetragonal and cubic zirconia, and alumina of two different particle sizes.

  4. The experience curve, option value, and the energy paradox

    International Nuclear Information System (INIS)

    Ansar, Jasmin; Sparks, Roger

    2009-01-01

    This paper develops a model to explain the 'energy paradox,' the inclination of households and firms to require very high internal rates of return in order to make energy-saving investments. The model abstracts from many features of such investments to focus on their irreversibility, the uncertainty of their future payoff streams, and the investor's anticipation of future technological advance. In this setting, the decision to invest in energy-saving technology can be delayed, providing option value. In addition, delay allows the potential investor to cash in on future experience-curve effects: With the passage of time, firms gain practical knowledge in producing and installing the energy-saving technology, enabling them to reduce the technology's up-front cost per unit of energy saved. We incorporate these fundamentals into a stochastic model where the investment's discounted benefits follow geometric Brownian motion. To demonstrate the model's capabilities, we generate simulation results for photovoltaic systems that highlight the experience-curve effect as a fundamental reason why households and firms delay making energy-saving investments until internal rates of return exceed values of 50% and higher, consistent with observations in the economics literature. We also explore altruistic motivations for energy conservation and the model's implications for both 'additionality' and the design of energy-conservation policy

  5. Experience curve for natural gas production by hydraulic fracturing

    International Nuclear Information System (INIS)

    Fukui, Rokuhei; Greenfield, Carl; Pogue, Katie; Zwaan, Bob van der

    2017-01-01

    From 2007 to 2012 shale gas production in the US expanded at an astounding average growth rate of over 50%/yr, and thereby increased nearly tenfold over this short time period alone. Hydraulic fracturing technology, or “fracking”, as well as new directional drilling techniques, played key roles in this shale gas revolution, by allowing for extraction of natural gas from previously unviable shale resources. Although hydraulic fracturing technology had been around for decades, it only recently became commercially attractive for large-scale implementation. As the production of shale gas rapidly increased in the US over the past decade, the wellhead price of natural gas dropped substantially. In this paper we express the relationship between wellhead price and cumulative natural gas output in terms of an experience curve, and obtain a learning rate of 13% for the industry using hydraulic fracturing technology. This learning rate represents a measure for the know-how and skills accumulated thus far by the US shale gas industry. The use of experience curves for renewable energy options such as solar and wind power has allowed analysts, practitioners, and policy makers to assess potential price reductions, and underlying cost decreases, for these technologies in the future. The reasons for price reductions of hydraulic fracturing are fundamentally different from those behind renewable energy technologies – hence they cannot be directly compared – and hydraulic fracturing may soon reach, or maybe has already attained, a lower bound for further price reductions, for instance as a result of its water requirements or environmental footprint. Yet, understanding learning-by-doing phenomena as expressed by an industry-wide experience curve for shale gas production can be useful for strategic planning in the gas sector, as well as assist environmental policy design, and serve more broadly as input for projections of energy system developments. - Highlights: • Hydraulic

  6. A retrospective analysis of compact fluorescent lamp experience curves and their correlations to deployment programs

    International Nuclear Information System (INIS)

    Smith, Sarah Josephine; Wei, Max; Sohn, Michael D.

    2016-01-01

    Experience curves are useful for understanding technology development and can aid in the design and analysis of market transformation programs. Here, we employ a novel approach to create experience curves, to examine both global and North American compact fluorescent lamp (CFL) data for the years 1990–2007. We move away from the prevailing method of fitting a single, constant, exponential curve to data and instead search for break points where changes in the learning rate may have occurred. Our analysis suggests a learning rate of approximately 21% for the period of 1990–1997, and 51% and 79% in global and North American datasets, respectively, after 1998. We use price data for this analysis; therefore our learning rates encompass developments beyond typical “learning by doing”, including supply chain impacts such as market competition. We examine correlations between North American learning rates and the initiation of new programs, abrupt technological advances, and economic and political events, and find an increased learning rate associated with design advancements and federal standards programs. Our findings support the use of segmented experience curves for retrospective and prospective technology analysis, and may imply that investments in technology programs have contributed to an increase of the CFL learning rate. - Highlights: • We develop a segmented regression technique to estimate historical CFL learning curves. • CFL experience curves do not have a constant learning rate. • CFLs exhibited a learning rate of approximately 21% from 1990 to 1997. • The CFL learning rate significantly increased after 1998. • Increased CFL learning rate is correlated to technology deployment programs.

  7. Initially curved microplates under electrostatic actuation: theory and experiment

    KAUST Repository

    Saghir, Shahid

    2016-07-01

    Microplates are the building blocks of many micro-electro-mechanical systems. It is common for them to experience initial curvature imperfection due to residual stresses caused by the micro fabrication process. Such plates are essentially different from perfectly flat ones and cannot be modeled using flat plate models. In this paper, we adopt a dynamic analog of the von Karman governing equations of imperfect plates. These equations are then used to develop a reduced order model based on the Galerkin procedure, to simulate the static and dynamic behavior of the microplate under electrostatic actuation. To validate the simulation results, an initially curved imperfect microplate made of silicon nitride is fabricated and tested. The static behaviour of the microplate is investigated when applying a DC voltage Vdc. Then, the dynamic behaviour of the microplate is examined under the application of a harmonic AC voltage, Vac, superimposed to Vdc. The simulation results show good agreement with the experimentally measured responses. © 2016 IOP Publishing Ltd.

  8. Exploring Alternative Characteristic Curve Approaches to Linking Parameter Estimates from the Generalized Partial Credit Model.

    Science.gov (United States)

    Roberts, James S.; Bao, Han; Huang, Chun-Wei; Gagne, Phill

    Characteristic curve approaches for linking parameters from the generalized partial credit model were examined for cases in which common (anchor) items are calibrated separately in two groups. Three of these approaches are simple extensions of the test characteristic curve (TCC), item characteristic curve (ICC), and operating characteristic curve…

  9. Rational Points on Curves of Genus 2: Experiments and Speculations

    OpenAIRE

    Stoll, Michael

    2009-01-01

    I will present results of computations providing statistics on rational points on (small) curves of genus 2 and use them to present several conjectures. Some of them are based on heuristic considerations, others are not.

  10. Experiments with conjugate gradient algorithms for homotopy curve tracking

    Science.gov (United States)

    Irani, Kashmira M.; Ribbens, Calvin J.; Watson, Layne T.; Kamat, Manohar P.; Walker, Homer F.

    1991-01-01

    There are algorithms for finding zeros or fixed points of nonlinear systems of equations that are globally convergent for almost all starting points, i.e., with probability one. The essence of all such algorithms is the construction of an appropriate homotopy map and then tracking some smooth curve in the zero set of this homotopy map. HOMPACK is a mathematical software package implementing globally convergent homotopy algorithms with three different techniques for tracking a homotopy zero curve, and has separate routines for dense and sparse Jacobian matrices. The HOMPACK algorithms for sparse Jacobian matrices use a preconditioned conjugate gradient algorithm for the computation of the kernel of the homotopy Jacobian matrix, a required linear algebra step for homotopy curve tracking. Here, variants of the conjugate gradient algorithm are implemented in the context of homotopy curve tracking and compared with Craig's preconditioned conjugate gradient method used in HOMPACK. The test problems used include actual large scale, sparse structural mechanics problems.

  11. Theory and experiments on Peano and Hilbert curve RFID tags

    Science.gov (United States)

    McVay, John; Hoorfar, Ahmad; Engheta, Nader

    2006-05-01

    Recently, there has been considerable interest in the area of Radio Frequency Identification (RFID) and Radio Frequency Tagging (RFTAG). This emerging area of interest can be applied for inventory control (commercial) as well as friend/foe identification (military) to name but a few. The current technology can be broken down into two main groups, namely passive and active RFID tags. Utilization of Space-Filling Curve (SFC) geometries, such as the Peano and Hilbert curves, has been recently investigated for use in completely passive RFID applications [1, 2]. In this work, we give an overview of our work on the space-filling curves and the potential for utilizing the electrically small, resonant characteristics of these curves for use in RFID technologies with an emphasis on the challenging issues involved when attempting to tag conductive objects. In particular, we investigate the possible use of these tags in conjunction with high impedance ground-planes made of Hilbert or Peano curve inclusions [3, 4] to develop electrically small RFID tags that may also radiate efficiently, within close proximity of large conductive objects [5].

  12. Cubic Bezier Curve Approach for Automated Offline Signature Verification with Intrusion Identification

    Directory of Open Access Journals (Sweden)

    Arun Vijayaragavan

    2014-01-01

    Full Text Available Authentication is a process of identifying person’s rights over a system. Many authentication types are used in various systems, wherein biometrics authentication systems are of a special concern. Signature verification is a basic biometric authentication technique used widely. The signature matching algorithm uses image correlation and graph matching technique which provides false rejection or acceptance. We proposed a model to compare knowledge from signature. Intrusion in the signature repository system results in copy of the signature that leads to false acceptance. Our approach uses a Bezier curve algorithm to identify the curve points and uses the behaviors of the signature for verification. An analyzing mobile agent is used to identify the input signature parameters and compare them with reference signature repository. It identifies duplication of signature over intrusion and rejects it. Experiments are conducted on a database with thousands of signature images from various sources and the results are favorable.

  13. Predicting Change in Postpartum Depression: An Individual Growth Curve Approach.

    Science.gov (United States)

    Buchanan, Trey

    Recently, methodologists interested in examining problems associated with measuring change have suggested that developmental researchers should focus upon assessing change at both intra-individual and inter-individual levels. This study used an application of individual growth curve analysis to the problem of maternal postpartum depression.…

  14. Effects of fog, driver experience and gender on driving behavior on S-curved road segments.

    Science.gov (United States)

    Li, Xiaomeng; Yan, Xuedong; Wong, S C

    2015-04-01

    Driving on curved roads has been recognized as a significant safety issue for many years. However, driver behavior and the interactions among variables that affect driver performance on curves is complicated and not well understood. Previous studies have investigated various factors that influence driver performance on right- or left-turn curves, but have paid little attention to the effects of foggy weather, driver experience and gender on driver performance on complex curves. A driving simulator experiment was conducted in this study to evaluate the relationships between driving behavior on a continuous S-curve and foggy weather, driver experience and gender. The process of negotiating a curve was divided into three stages consisting of a straight segment, the transition from the straight segment to the S-curve and the S-curve. The experimental results indicated that drivers tended to drive more cautiously in heavy fog, but the driving risk was still increased, especially in the transition stage from the straight segment to the S-curve. The non-professional (NP) drivers were less sensitive to the impending change in the road geometry, and less skilled in both longitudinal and lateral vehicle control than the professional drivers. The NP female drivers in particular were found to be the most vulnerable group in S-curve driving. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. A new approach to the analysis of Mira light curves

    International Nuclear Information System (INIS)

    Mennessier, M.O.; Barthes, D.; Mattei, J.A.

    1990-01-01

    Two different but complementary methods for predicting Mira luminosities are presented. One method is derived from a Fourier analysis, it requires performing deconvolution, and its results are not certain due to the inherent instability of deconvolution problems. The other method is a learning method utilizing artificial intelligence techniques where a light curve is presented as an ordered sequence of pseudocycles, and rules are learned by linking the characteristics of several consecutive pseudocycles to one characteristic of the future cycle. It is observed that agreement between these methods is obtainable when it is possible to eliminate similar false frequencies from the preliminary power spectrum and to improve the degree of confidence in the rules

  16. A Simplified Micromechanical Modeling Approach to Predict the Tensile Flow Curve Behavior of Dual-Phase Steels

    Science.gov (United States)

    Nanda, Tarun; Kumar, B. Ravi; Singh, Vishal

    2017-11-01

    Micromechanical modeling is used to predict material's tensile flow curve behavior based on microstructural characteristics. This research develops a simplified micromechanical modeling approach for predicting flow curve behavior of dual-phase steels. The existing literature reports on two broad approaches for determining tensile flow curve of these steels. The modeling approach developed in this work attempts to overcome specific limitations of the existing two approaches. This approach combines dislocation-based strain-hardening method with rule of mixtures. In the first step of modeling, `dislocation-based strain-hardening method' was employed to predict tensile behavior of individual phases of ferrite and martensite. In the second step, the individual flow curves were combined using `rule of mixtures,' to obtain the composite dual-phase flow behavior. To check accuracy of proposed model, four distinct dual-phase microstructures comprising of different ferrite grain size, martensite fraction, and carbon content in martensite were processed by annealing experiments. The true stress-strain curves for various microstructures were predicted with the newly developed micromechanical model. The results of micromechanical model matched closely with those of actual tensile tests. Thus, this micromechanical modeling approach can be used to predict and optimize the tensile flow behavior of dual-phase steels.

  17. Initially curved microplates under electrostatic actuation: theory and experiment

    KAUST Repository

    Saghir, Shahid; Bellaredj, Mohammed Lamine Faycal; Ramini, Abdallah; Younis, Mohammad I.

    2016-01-01

    Microplates are the building blocks of many micro-electro-mechanical systems. It is common for them to experience initial curvature imperfection due to residual stresses caused by the micro fabrication process. Such plates are essentially different

  18. Lie-Hamilton systems on curved spaces: a geometrical approach

    Science.gov (United States)

    Herranz, Francisco J.; de Lucas, Javier; Tobolski, Mariusz

    2017-12-01

    A Lie-Hamilton system is a nonautonomous system of first-order ordinary differential equations describing the integral curves of a t-dependent vector field taking values in a finite-dimensional Lie algebra, a Vessiot-Guldberg Lie algebra, of Hamiltonian vector fields relative to a Poisson structure. Its general solution can be written as an autonomous function, the superposition rule, of a generic finite family of particular solutions and a set of constants. We pioneer the study of Lie-Hamilton systems on Riemannian spaces (sphere, Euclidean and hyperbolic plane), pseudo-Riemannian spaces (anti-de Sitter, de Sitter, and Minkowski spacetimes) as well as on semi-Riemannian spaces (Newtonian spacetimes). Their corresponding constants of motion and superposition rules are obtained explicitly in a geometric way. This work extends the (graded) contraction of Lie algebras to a contraction procedure for Lie algebras of vector fields, Hamiltonian functions, and related symplectic structures, invariants, and superposition rules.

  19. Integrated healthcare networks' performance: a growth curve modeling approach.

    Science.gov (United States)

    Wan, Thomas T H; Wang, Bill B L

    2003-05-01

    This study examines the effects of integration on the performance ratings of the top 100 integrated healthcare networks (IHNs) in the United States. A strategic-contingency theory is used to identify the relationship of IHNs' performance to their structural and operational characteristics and integration strategies. To create a database for the panel study, the top 100 IHNs selected by the SMG Marketing Group in 1998 were followed up in 1999 and 2000. The data were merged with the Dorenfest data on information system integration. A growth curve model was developed and validated by the Mplus statistical program. Factors influencing the top 100 IHNs' performance in 1998 and their subsequent rankings in the consecutive years were analyzed. IHNs' initial performance scores were positively influenced by network size, number of affiliated physicians and profit margin, and were negatively associated with average length of stay and technical efficiency. The continuing high performance, judged by maintaining higher performance scores, tended to be enhanced by the use of more managerial or executive decision-support systems. Future studies should include time-varying operational indicators to serve as predictors of network performance.

  20. A dynamic approach to the Environmental Kuznets Curve hypothesis

    International Nuclear Information System (INIS)

    Agras, Jean; Chapman, Duane

    1999-01-01

    The Environmental Kuznets Curve (EKC) hypothesis states that pollution levels increase as a country develops, but begin to decrease as rising incomes pass beyond a turning point. In EKC analyses, the relationship between environmental degradation and income is usually expressed as a quadratic function with the turning point occurring at a maximum pollution level. Other explanatory variables have been included in these models, but income regularly has had the most significant effect on indicators of environmental quality. One variable consistently omitted in these relationships is the price of energy. This paper analyzes previous models to illustrate the importance of prices in these models and then includes prices in an econometric EKC framework testing energy/income and CO 2 /income relationships. These long-run price/income models find that income is no longer the most relevant indicator of environmental quality or energy demand. Indeed, we find no significant evidence for the existence of an EKC within the range of current incomes for energy in the presence of price and trade variables

  1. Electrolyte solutions at curved electrodes. II. Microscopic approach.

    Science.gov (United States)

    Reindl, Andreas; Bier, Markus; Dietrich, S

    2017-04-21

    Density functional theory is used to describe electrolyte solutions in contact with electrodes of planar or spherical shape. For the electrolyte solutions, we consider the so-called civilized model, in which all species present are treated on equal footing. This allows us to discuss the features of the electric double layer in terms of the differential capacitance. The model provides insight into the microscopic structure of the electric double layer, which goes beyond the mesoscopic approach studied in Paper I. This enables us to judge the relevance of microscopic details, such as the radii of the particles forming the electrolyte solutions or the dipolar character of the solvent particles, and to compare the predictions of various models. Similar to Paper I, a general behavior is observed for small radii of the electrode in that in this limit the results become independent of the surface charge density and of the particle radii. However, for large electrode radii, non-trivial behaviors are observed. Especially the particle radii and the surface charge density strongly influence the capacitance. From the comparison with the Poisson-Boltzmann approach, it becomes apparent that the shape of the electrode determines whether the microscopic details of the full civilized model have to be taken into account or whether already simpler models yield acceptable predictions.

  2. Development Process and Technical Aspects of Laparoscopic Hepatectomy: Learning Curve Based on 15 Years of Experience.

    Science.gov (United States)

    Komatsu, Shohei; Scatton, Olivier; Goumard, Claire; Sepulveda, Ailton; Brustia, Raffaele; Perdigao, Fabiano; Soubrane, Olivier

    2017-05-01

    Laparoscopic hepatectomy continues to be a challenging operation associated with a steep learning curve. This study aimed to evaluate the learning process during 15 years of experience with laparoscopic hepatectomy and to identify approaches to standardization of this procedure. Prospectively collected data of 317 consecutive laparoscopic hepatectomies performed from January 2000 to December 2014 were reviewed retrospectively. The operative procedures were classified into 4 categories (minor hepatectomy, left lateral sectionectomy [LLS], left hepatectomy, and right hepatectomy), and indications were classified into 5 categories (benign-borderline tumor, living donor, metastatic liver tumor, biliary malignancy, and hepatocellular carcinoma). During the first 10 years, the procedures were limited mainly to minor hepatectomy and LLS, and the indications were limited to benign-borderline tumor and living donor. Implementation of major hepatectomy rapidly increased the proportion of malignant tumors, especially hepatocellular carcinoma, starting from 2011. Conversion rates decreased with experience for LLS (13.3% vs 3.4%; p = 0.054) and left hepatectomy (50.0% vs 15.0%; p = 0.012), but not for right hepatectomy (41.4% vs 35.7%; p = 0.661). Our 15-year experience clearly demonstrates the stepwise procedural evolution from LLS through left hepatectomy to right hepatectomy, as well as the trend in indications from benign-borderline tumor/living donor to malignant tumors. In contrast to LLS and left hepatectomy, a learning curve was not observed for right hepatectomy. The ongoing development process can contribute to faster standardization necessary for future advances in laparoscopic hepatectomy. Copyright © 2017 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  3. Evaluation of viewing experiences induced by a curved three-dimensional display

    Science.gov (United States)

    Mun, Sungchul; Park, Min-Chul; Yano, Sumio

    2015-10-01

    Despite an increased need for three-dimensional (3-D) functionality in curved displays, comparisons pertinent to human factors between curved and flat panel 3-D displays have rarely been tested. This study compared stereoscopic 3-D viewing experiences induced by a curved display with those of a flat panel display by evaluating subjective and objective measures. Twenty-four participants took part in the experiments and viewed 3-D content with two different displays (flat and curved 3-D display) within a counterbalanced and within-subject design. For the 30-min viewing condition, a paired t-test showed significantly reduced P300 amplitudes, which were caused by engagement rather than cognitive fatigue, in the curved 3-D viewing condition compared to the flat 3-D viewing condition at P3 and P4. No significant differences in P300 amplitudes were observed for 60-min viewing. Subjective ratings of realness and engagement were also significantly higher in the curved 3-D viewing condition than in the flat 3-D viewing condition for 30-min viewing. Our findings support that curved 3-D displays can be effective for enhancing engagement among viewers based on specific viewing times and environments.

  4. Assessment of two theoretical methods to estimate potentiometric titration curves of peptides: comparison with experiment.

    Science.gov (United States)

    Makowska, Joanna; Bagiñska, Katarzyna; Makowski, Mariusz; Jagielska, Anna; Liwo, Adam; Kasprzykowski, Franciszek; Chmurzyñski, Lech; Scheraga, Harold A

    2006-03-09

    We compared the ability of two theoretical methods of pH-dependent conformational calculations to reproduce experimental potentiometric titration curves of two models of peptides: Ac-K5-NHMe in 95% methanol (MeOH)/5% water mixture and Ac-XX(A)7OO-NH2 (XAO) (where X is diaminobutyric acid, A is alanine, and O is ornithine) in water, methanol (MeOH), and dimethyl sulfoxide (DMSO), respectively. The titration curve of the former was taken from the literature, and the curve of the latter was determined in this work. The first theoretical method involves a conformational search using the electrostatically driven Monte Carlo (EDMC) method with a low-cost energy function (ECEPP/3 plus the SRFOPT surface-solvation model, assumming that all titratable groups are uncharged) and subsequent reevaluation of the free energy at a given pH with the Poisson-Boltzmann equation, considering variable protonation states. In the second procedure, molecular dynamics (MD) simulations are run with the AMBER force field and the generalized Born model of electrostatic solvation, and the protonation states are sampled during constant-pH MD runs. In all three solvents, the first pKa of XAO is strongly downshifted compared to the value for the reference compounds (ethylamine and propylamine, respectively); the water and methanol curves have one, and the DMSO curve has two jumps characteristic of remarkable differences in the dissociation constants of acidic groups. The predicted titration curves of Ac-K5-NHMe are in good agreement with the experimental ones; better agreement is achieved with the MD-based method. The titration curves of XAO in methanol and DMSO, calculated using the MD-based approach, trace the shape of the experimental curves, reproducing the pH jump, while those calculated with the EDMC-based approach and the titration curve in water calculated using the MD-based approach have smooth shapes characteristic of the titration of weak multifunctional acids with small differences

  5. Master curve approach to monitor fracture toughness of reactor pressure vessels in nuclear power plants

    International Nuclear Information System (INIS)

    2009-10-01

    A series of coordinated research projects (CRPs) have been sponsored by the IAEA, starting in the early 1970s, focused on neutron radiation effects on reactor pressure vessel (RPV) steels. The purpose of the CRPs was to develop correlative comparisons to test the uniformity of results through coordinated international research studies and data sharing. The overall scope of the eighth CRP (CRP-8), Master Curve Approach to Monitor Fracture Toughness of Reactor Pressure Vessels in Nuclear Power Plants, has evolved from previous CRPs which have focused on fracture toughness related issues. The ultimate use of embrittlement understanding is application to assure structural integrity of the RPV under current and future operation and accident conditions. The Master Curve approach for assessing the fracture toughness of a sampled irradiated material has been gaining acceptance throughout the world. This direct measurement of fracture toughness approach is technically superior to the correlative and indirect methods used in the past to assess irradiated RPV integrity. Several elements have been identified as focal points for Master Curve use: (i) limits of applicability for the Master Curve at the upper range of the transition region for loading quasi-static to dynamic/impact loading rates; (ii) effects of non-homogeneous material or changes due to environment conditions on the Master Curve, and how heterogeneity can be integrated into a more inclusive Master Curve methodology; (iii) importance of fracture mode differences and changes affect the Master Curve shape. The collected data in this report represent mostly results from non-irradiated testing, although some results from test reactor irradiations and plant surveillance programmes have been included as available. The results presented here should allow utility engineers and scientists to directly measure fracture toughness using small surveillance size specimens and apply the results using the Master Curve approach

  6. Cost development of future technologies for power generation-A study based on experience curves and complementary bottom-up assessments

    International Nuclear Information System (INIS)

    Neij, Lena

    2008-01-01

    Technology foresight studies have become an important tool in identifying realistic ways of reducing the impact of modern energy systems on the climate and the environment. Studies on the future cost development of advanced energy technologies are of special interest. One approach widely adopted for the analysis of future cost is the experience curve approach. The question is, however, how robust this approach is, and which experience curves should be used in energy foresight analysis. This paper presents an analytical framework for the analysis of future cost development of new energy technologies for electricity generation; the analytical framework is based on an assessment of available experience curves, complemented with bottom-up analysis of sources of cost reductions and, for some technologies, judgmental expert assessments of long-term development paths. The results of these three methods agree in most cases, i.e. the cost (price) reductions described by the experience curves match the incremental cost reduction described in the bottom-up analysis and the judgmental expert assessments. For some technologies, the bottom-up analysis confirms large uncertainties in future cost development not captured by the experience curves. Experience curves with a learning rate ranging from 0% to 20% are suggested for the analysis of future cost development

  7. Explaining experience curves for new energy technologies. A case study of liquefied natural gas

    International Nuclear Information System (INIS)

    Greaker, Mads; Lund Sagen, Eirik

    2008-01-01

    Many new energy technologies seem to experience a fall in unit price as they mature. In this paper we study the unit price of liquefying natural gas in order to make it transportable by ship to gas power installations all over the world. Our point of departure is the experience curve approach, however unlike many other studies of new energy technologies, we also seek to account for autonomous technological change, scale effects and the effects of upstream competition among technology suppliers. To our surprise we find that upstream competition is by far the most important factor contributing to the fall in unit price. With respect to the natural gas business, this may have implications for the future development in prices as the effect of increased upstream competition is temporary and likely to weaken a lot sooner than effects from learning and technological change. Another more general policy implication, is that while promoting new energy technologies, governments must not forget to pay attention to competition policy. (author)

  8. Potential errors when fitting experience curves by means of spreadsheet software

    International Nuclear Information System (INIS)

    Sark, W.G.J.H.M. van; Alsema, E.A.

    2010-01-01

    Progress ratios (PRs) are widely used in forecasting development of many technologies; they are derived from historical data represented in experience curves. Fitting the double logarithmic graphs is easily done with spreadsheet software like Microsoft Excel, by adding a trend line to the graph. However, it is unknown to many that these data are transformed to linear data before a fit is performed. This leads to erroneous results or a transformation bias in the PR, as we demonstrate using the experience curve for photovoltaic technology: logarithmic transformation leads to overestimates of progress ratios and underestimates of goodness of fit. Therefore, other graphing and analysis software is recommended.

  9. Fracture toughness evaluation of steels through master curve approach using Charpy impact specimens

    International Nuclear Information System (INIS)

    Chatterjee, S.; Sriharsha, H.K.; Shah, Priti Kotak

    2007-01-01

    The master curve approach can be used for the evaluation of fracture toughness of all steels which exhibit a transition between brittle to ductile mode of fracture with increasing temperature, and to monitor the extent of embrittlement caused by metallurgical damage mechanisms. This paper details the procedure followed to evaluate the fracture toughness of a typical ferritic steel used as material for pressure vessels. The potential of master curve approach to overcome the inherent limitations of the estimation of fracture toughness using ASME Code reference toughness is also illustrated. (author)

  10. Explaining the experience curve: Cost reductions of Brazilian ethanol from sugarcane

    International Nuclear Information System (INIS)

    van den Wall Bake, J.D.; Junginger, M.; Faaij, A.; Poot, T.; Walter, A.

    2009-01-01

    Production costs of bio-ethanol from sugarcane in Brazil have declined continuously over the last three decades. The aims of this study are to determine underlying reasons behind these cost reductions, and to assess whether the experience curve concept can be used to describe the development of feedstock costs and industrial production costs. The analysis was performed using average national costs data, a number of prices (as a proxy for production costs) and data on annual Brazilian production volumes. Results show that the progress ratio (PR) for feedstock costs is 0.68 and 0.81 for industrial costs (excluding feedstock costs). The experience curve of total production costs results in a PR of 0.80. Cost breakdowns of sugarcane production show that all sub-processes contributed to the total, but that increasing yields have been the main driving force. Industrial costs mainly decreased because of increasing scales of the ethanol plants. Total production costs at present are approximately 340 US$/m ethanol 3 (16 US$/GJ). Based on the experience curves for feedstock and industrial costs, total ethanol production costs in 2020 are estimated between US$ 200 and 260/m 3 (9.4-12.2 US$/GJ). We conclude that using disaggregated experience curves for feedstock and industrial processing costs provide more insights into the factors that lowered costs in the past, and allow more accurate estimations for future cost developments. (author)

  11. Potential errors when fitting experience curves by means of spreadsheet software

    NARCIS (Netherlands)

    van Sark, W.G.J.H.M.|info:eu-repo/dai/nl/074628526; Alsema, E.A.|info:eu-repo/dai/nl/073416258

    2010-01-01

    Progress ratios (PRs) are widely used in forecasting development of many technologies; they are derived from historical data represented in experience curves. Fitting the double logarithmic graphs is easily done with spreadsheet software like Microsoft Excel, by adding a trend line to the graph.

  12. Short-radius horizontal well re-entry learning curve: prize, cost and operational experience

    Energy Technology Data Exchange (ETDEWEB)

    Boote, K. [Ocelot Energy Inc., Calgary, AB (Canada); MacDonald, R. [Lauron Engineering Ltd, Calgary, AB (Canada)

    1997-12-01

    Six mature vertical wells in Alberta belonging to Ocelot Energy Inc., were reentered and drilled horizontally. Experiences gained, the modifications made to the drilling program and the rewards in the form of incremental oil, were discussed. Details of pre- and post-performance, operational experiences with exiting the casing, building the curve, overbalance versus underbalanced drilling, motors, directional equipment, setting liners, remedial workovers and the cost of the operation were part of the discussion.

  13. DEVELOPING AN EXCELLENT SEDIMENT RATING CURVE FROM ONE HYDROLOGICAL YEAR SAMPLING PROGRAMME DATA: APPROACH

    Directory of Open Access Journals (Sweden)

    Preksedis M. Ndomba

    2008-01-01

    Full Text Available This paper presents preliminary findings on the adequacy of one hydrological year sampling programme data in developing an excellent sediment rating curve. The study case is a 1DD1 subcatchment in the upstream of Pangani River Basin (PRB, located in the North Eastern part of Tanzania. 1DD1 is the major runoff-sediment contributing tributary to the downstream hydropower reservoir, the Nyumba Ya Mungu (NYM. In literature sediment rating curve method is known to underestimate the actual sediment load. In the case of developing countries long-term sediment sampling monitoring or conservation campaigns have been reported as unworkable options. Besides, to the best knowledge of the authors, to date there is no consensus on how to develop an excellent rating curve. Daily-midway and intermittent-cross section sediment samples from Depth Integrating sampler (D-74 were used to calibrate the subdaily automatic sediment pumping sampler (ISCO 6712 near bank point samples for developing the rating curve. Sediment load correction factors were derived from both statistical bias estimators and actual sediment load approaches. It should be noted that the ongoing study is guided by findings of other studies in the same catchment. For instance, long term sediment yield rate estimated based on reservoir survey validated the performance of the developed rating curve. The result suggests that excellent rating curve could be developed from one hydrological year sediment sampling programme data. This study has also found that uncorrected rating curve underestimates sediment load. The degreeof underestimation depends on the type of rating curve developed and data used.

  14. Memristance controlling approach based on modification of linear M—q curve

    International Nuclear Information System (INIS)

    Liu Hai-Jun; Li Zhi-Wei; Yu Hong-Qi; Sun Zhao-Lin; Nie Hong-Shan

    2014-01-01

    The memristor has broad application prospects in many fields, while in many cases, those fields require accurate impedance control. The nonlinear model is of great importance for realizing memristance control accurately, but the implementing complexity caused by iteration has limited the actual application of this model. Considering the approximate linear characteristics at the middle region of the memristance-charge (M—q) curve of the nonlinear model, this paper proposes a memristance controlling approach, which is achieved by linearizing the middle region of the M—q curve of the nonlinear memristor, and establishes the linear relationship between memristances M and input excitations so that it can realize impedance control precisely by only adjusting input signals briefly. First, it analyzes the feasibility for linearizing the middle part of the M—q curve of the memristor with a nonlinear model from the qualitative perspective. Then, the linearization equations of the middle region of the M—q curve is constructed by using the shift method, and under a sinusoidal excitation case, the analytical relation between the memristance M and the charge time t is derived through the Taylor series expansions. At last, the performance of the proposed approach is demonstrated, including the linearizing capability for the middle part of the M—q curve of the nonlinear model memristor, the controlling ability for memristance M, and the influence of input excitation on linearization errors. (interdisciplinary physics and related areas of science and technology)

  15. Development of theoretical oxygen saturation calibration curve based on optical density ratio and optical simulation approach

    Science.gov (United States)

    Jumadi, Nur Anida; Beng, Gan Kok; Ali, Mohd Alauddin Mohd; Zahedi, Edmond; Morsin, Marlia

    2017-09-01

    The implementation of surface-based Monte Carlo simulation technique for oxygen saturation (SaO2) calibration curve estimation is demonstrated in this paper. Generally, the calibration curve is estimated either from the empirical study using animals as the subject of experiment or is derived from mathematical equations. However, the determination of calibration curve using animal is time consuming and requires expertise to conduct the experiment. Alternatively, an optical simulation technique has been used widely in the biomedical optics field due to its capability to exhibit the real tissue behavior. The mathematical relationship between optical density (OD) and optical density ratios (ODR) associated with SaO2 during systole and diastole is used as the basis of obtaining the theoretical calibration curve. The optical properties correspond to systolic and diastolic behaviors were applied to the tissue model to mimic the optical properties of the tissues. Based on the absorbed ray flux at detectors, the OD and ODR were successfully calculated. The simulation results of optical density ratio occurred at every 20 % interval of SaO2 is presented with maximum error of 2.17 % when comparing it with previous numerical simulation technique (MC model). The findings reveal the potential of the proposed method to be used for extended calibration curve study using other wavelength pair.

  16. The Quantitative Evaluation of Functional Neuroimaging Experiments: Mutual Information Learning Curves

    DEFF Research Database (Denmark)

    Kjems, Ulrik; Hansen, Lars Kai; Anderson, Jon

    2002-01-01

    Learning curves are presented as an unbiased means for evaluating the performance of models for neuroimaging data analysis. The learning curve measures the predictive performance in terms of the generalization or prediction error as a function of the number of independent examples (e.g., subjects......) used to determine the parameters in the model. Cross-validation resampling is used to obtain unbiased estimates of a generic multivariate Gaussian classifier, for training set sizes from 2 to 16 subjects. We apply the framework to four different activation experiments, in this case \\$\\backslash......\\$[/sup 15/ O]water data sets, although the framework is equally valid for multisubject fMRI studies. We demonstrate how the prediction error can be expressed as the mutual information between the scan and the scan label, measured in units of bits. The mutual information learning curve can be used...

  17. An Approach of Estimating Individual Growth Curves for Young Thoroughbred Horses Based on Their Birthdays

    Science.gov (United States)

    ONODA, Tomoaki; YAMAMOTO, Ryuta; SAWAMURA, Kyohei; MURASE, Harutaka; NAMBO, Yasuo; INOUE, Yoshinobu; MATSUI, Akira; MIYAKE, Takeshi; HIRAI, Nobuhiro

    2014-01-01

    ABSTRACT We propose an approach of estimating individual growth curves based on the birthday information of Japanese Thoroughbred horses, with considerations of the seasonal compensatory growth that is a typical characteristic of seasonal breeding animals. The compensatory growth patterns appear during only the winter and spring seasons in the life of growing horses, and the meeting point between winter and spring depends on the birthday of each horse. We previously developed new growth curve equations for Japanese Thoroughbreds adjusting for compensatory growth. Based on the equations, a parameter denoting the birthday information was added for the modeling of the individual growth curves for each horse by shifting the meeting points in the compensatory growth periods. A total of 5,594 and 5,680 body weight and age measurements of Thoroughbred colts and fillies, respectively, and 3,770 withers height and age measurements of both sexes were used in the analyses. The results of predicted error difference and Akaike Information Criterion showed that the individual growth curves using birthday information better fit to the body weight and withers height data than not using them. The individual growth curve for each horse would be a useful tool for the feeding managements of young Japanese Thoroughbreds in compensatory growth periods. PMID:25013356

  18. Accuracy of progress ratios determined from experience curves: the case of photovoltaic technology development

    OpenAIRE

    van Sark, W.G.J.H.M.; Alsema, E.A.; Junginger, H.M.; de Moor, H.H.C.; Schaeffer, G.J.

    2008-01-01

    Learning curves are extensively used in policy and scenario studies. Progress ratios (PRs) are derived from historical data and are used for forecasting cost development of many technologies, including photovoltaics (PV). Forecasts are highly sensitive to uncertainties in the PR. A PR usually is determined together with the coefficient of determination R2, which should approach unity for a good fit of the available data. Although the R2 is instructive, we recommend using the error in the PR d...

  19. Scanning the melting curve of tungsten by a submicrosecond wire-explosion experiment

    International Nuclear Information System (INIS)

    Kloss, A.; Hess, H.; Schneidenbach, H.; Grossjohann, R.

    1999-01-01

    Measurements of temperature and density during a wire-explosion experiment at atmospheric pressure are described. The measurements encompass a parameter range from the solid to near the critical point. The influence of a polytetra-fluoroethylene coating of the wire, necessary to prevent surface discharges, on the temperature and density measurements is investigated. The melting curve of tungsten up to 4,000 K is determined

  20. Wright meets Markowitz: How standard portfolio theory changes when assets are technologies following experience curves

    OpenAIRE

    Way, Rupert; Lafond, François; Farmer, J. Doyne; Lillo, Fabrizio; Panchenko, Valentyn

    2017-01-01

    This paper considers how to optimally allocate investments in a portfolio of competing technologies. We introduce a simple model representing the underlying trade-off - between investing enough effort in any one project to spur rapid progress, and diversifying effort over many projects simultaneously to hedge against failure. We use stochastic experience curves to model the idea that investing more in a technology reduces its unit costs, and we use a mean-variance objective function to unders...

  1. Non-Constant Learning Rates in Retrospective Experience Curve Analyses and their Correlation to Deployment Programs

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Smith, Sarah J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sohn, Michael D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-07-16

    A key challenge for policy-makers and technology market forecasters is to estimate future technology costs and in particular the rate of cost reduction versus production volume. A related, critical question is what role should state and federal governments have in advancing energy efficient and renewable energy technologies? This work provides retrospective experience curves and learning rates for several energy-related technologies, each of which have a known history of federal and state deployment programs. We derive learning rates for eight technologies including energy efficient lighting technologies, stationary fuel cell systems, and residential solar photovoltaics, and provide an overview and timeline of historical deployment programs such as state and federal standards and state and national incentive programs for each technology. Piecewise linear regimes are observed in a range of technology experience curves, and public investments or deployment programs are found to be strongly correlated to an increase in learning rate across multiple technologies. A downward bend in the experience curve is found in 5 out of the 8 energy-related technologies presented here (electronic ballasts, magnetic ballasts, compact fluorescent lighting, general service fluorescent lighting, and the installed cost of solar PV). In each of the five downward-bending experience curves, we believe that an increase in the learning rate can be linked to deployment programs to some degree. This work sheds light on the endogenous versus exogenous contributions to technological innovation and highlights the impact of exogenous government sponsored deployment programs. This work can inform future policy investment direction and can shed light on market transformation and technology learning behavior.

  2. Predicting the costs of photovoltaic solar modules in 2020 using experience curve models

    International Nuclear Information System (INIS)

    La Tour, Arnaud de; Glachant, Matthieu; Ménière, Yann

    2013-01-01

    Except in few locations, photovoltaic generated electricity remains considerably more expensive than conventional sources. It is however expected that innovation and learning-by-doing will lead to drastic cuts in production cost in the near future. The goal of this paper is to predict the cost of PV modules out to 2020 using experience curve models, and to draw implications about the cost of PV electricity. Using annual data on photovoltaic module prices, cumulative production, R and D knowledge stock and input prices for silicon and silver over the period 1990–2011, we identify a experience curve model which minimizes the difference between predicted and actual module prices. This model predicts a 67% decrease of module price from 2011 to 2020. This rate implies that the cost of PV generated electricity will reach that of conventional electricity by 2020 in the sunniest countries with annual solar irradiation of 2000 kWh/year or more, such as California, Italy, and Spain. - Highlights: • We predict the cost of PV modules out to 2020 using experience curve models. • The model predicts a 67% decrease of module price from 2011 to 2020. • We draw implications about the cost of PV electricity

  3. LEARNING CURVE IN SINGLE-LEVEL MINIMALLY INVASIVE TLIF: EXPERIENCE OF A NEUROSURGEON

    Directory of Open Access Journals (Sweden)

    Samuel Romano-Feinholz

    Full Text Available ABSTRACT Objective: To describe the learning curve that shows the progress of a single neurosurgeon when performing single-level MI-TLIF. Methods: We included 99 consecutive patients who underwent single-level MI-TLIF by the same neurosurgeon (JASS. Patient’s demographic characteristics were analyzed. In addition, surgical time, intraoperative blood loss and hospital stay were evaluated. The learning curves were calculated with a piecewise regression model. Results: The mean age was 54.6 years. The learning curves showed an inverse relationship between the surgical experience and the variable analyzed, reaching an inflection point for surgical time in case 43 and for blood loss in case 48. The mean surgical time was 203.3 minutes (interquartile range [IQR] 150-240 minutes, intraoperative bleeding was 97.4ml (IQR 40-100ml and hospital stay of four days (IQR 3-5 days. Conclusions: MI-TLIF is a very frequent surgical procedure due to its effectiveness and safety, which has shown similar results to open procedure. According to this study, the required learning curve is slightly higher than for open procedures, and is reached after about 45 cases.

  4. Prediction of ion-exchange column breakthrough curves by constant-pattern wave approach.

    Science.gov (United States)

    Lee, I-Hsien; Kuan, Yu-Chung; Chern, Jia-Ming

    2008-03-21

    The release of heavy metals from industrial wastewaters represents one of major threats to environment. Compared with chemical precipitation method, fixed-bed ion-exchange process can effectively remove heavy metals from wastewaters and generate no hazardous sludge. In order to design and operate fixed-bed ion-exchange processes successfully, it is very important to understand the column dynamics. In this study, the column experiments for Cu2+/H+, Zn2+/H+, and Cd2+/H+ systems using Amberlite IR-120 were performed to measure the breakthrough curves under varying operating conditions. The experimental results showed that total cation concentration in the mobile-phase played a key role on the breakthrough curves; a higher feed concentration resulted in an earlier breakthrough. Furthermore, the column dynamics was also predicted by self-sharpening and constant-pattern wave models. The self-sharpening wave model assuming local ion-exchange equilibrium could provide a simple and quick estimation for the breakthrough volume, but the predicted breakthrough curves did not match the experimental data very well. On the contrary, the constant-pattern wave model using a constant driving force model for finite ion-exchange rate provided a better fit to the experimental data. The obtained liquid-phase mass transfer coefficient was correlated to the flow velocity and other operating parameters; the breakthrough curves under varying operating conditions could thus be predicted by the constant-pattern wave model using the correlation.

  5. A Bayesian inference approach to unveil supply curves in electricity markets

    DEFF Research Database (Denmark)

    Mitridati, Lesia Marie-Jeanne Mariane; Pinson, Pierre

    2017-01-01

    in the literature on modeling this uncertainty. In this study we introduce a Bayesian inference approach to reveal the aggregate supply curve in a day-ahead electricity market. The proposed algorithm relies on Markov Chain Monte Carlo and Sequential Monte Carlo methods. The major appeal of this approach......With increased competition in wholesale electricity markets, the need for new decision-making tools for strategic producers has arisen. Optimal bidding strategies have traditionally been modeled as stochastic profit maximization problems. However, for producers with non-negligible market power...

  6. Application of Bimodal Master Curve Approach on KSNP RPV steel SA508 Gr. 3

    International Nuclear Information System (INIS)

    Kim, Jongmin; Kim, Minchul; Choi, Kwonjae; Lee, Bongsang

    2014-01-01

    In this paper, the standard MC approach and BMC are applied to the forging material of the KSNP RPV steel SA508 Gr. 3. A series of fracture toughness tests were conducted in the DBTT transition region, and fracture toughness specimens were extracted from four regions, i.e., the surface, 1/8T, 1/4T and 1/2T. Deterministic material inhomogeneity was reviewed through a conventional MC approach and the random inhomogeneity was evaluated by BMC. In the present paper, four regions, surface, 1/8T, 1/4T and 1/2T, were considered for the fracture toughness specimens of KSNP (Korean Standard Nuclear Plant) SA508 Gr. 3 steel to provide deterministic material inhomogeneity and review the applicability of BMC. T0 determined by a conventional MC has a low value owing to the higher quenching rate at the surface as expected. However, more than about 15% of the KJC values lay above the 95% probability curves indexed with the standard MC T0 at the surface and 1/8T, which implies the existence of inhomogeneity in the material. To review the applicability of the BMC method, the deterministic inhomogeneity owing to the extraction location and quenching rate is treated as random inhomogeneity. Although the lower bound and upper bound curve of the BMC covered more KJC values than that of the conventional MC, there is no significant relationship between the BMC analysis lines and measured KJC values in the higher toughness distribution, and BMC and MC provide almost the same T0 values. Therefore, the standard MC evaluation method for this material is appropriate even though the standard MC has a narrow upper/lower bound curve range from the RPV evaluation point of view. The material is not homogeneous in reality. Such inhomogeneity comes in the effect of material inhomogeneity depending on the specimen location, heat treatment, and whole manufacturing process. The conventional master curve has a limitation to be applied to a large scatted data of fracture toughness such as the weld region

  7. Greenhouse gas abatement cost curves of the residential heating market. A microeconomic approach

    International Nuclear Information System (INIS)

    Dieckhoener, Caroline; Hecking, Harald

    2012-01-01

    In this paper, we develop a microeconomic approach to deduce greenhouse gas abatement cost curves of the residential heating sector. By accounting for household behavior, we find that welfare-based abatement costs are generally higher than pure technical equipment costs. Our results are based on a microsimulation of private households' investment decision for heating systems until 2030. The households' investment behavior in the simulation is derived from a discrete choice estimation which allows investigating the welfare costs of different abatement policies in terms of the compensating variation and the excess burden. We simulate greenhouse gas abatements and welfare costs of carbon taxes and subsidies on heating system investments until 2030 to deduce abatement curves. Given utility maximizing households, our results suggest a carbon tax to be the welfare efficient policy. Assuming behavioral misperceptions instead, a subsidy on investments might have lower marginal greenhouse gas abatement costs than a carbon tax.

  8. Curve aligning approach for gait authentication based on a wearable accelerometer

    International Nuclear Information System (INIS)

    Sun, Hu; Yuao, Tao

    2012-01-01

    Gait authentication based on a wearable accelerometer is a novel biometric which can be used for identity identification, medical rehabilitation and early detection of neurological disorders. The method for matching gait patterns tells heavily on authentication performances. In this paper, curve aligning is introduced as a new method for matching gait patterns and it is compared with correlation and dynamic time warping (DTW). A support vector machine (SVM) is proposed to fuse pattern-matching methods in a decision level. Accelerations collected from ankles of 22 walking subjects are processed for authentications in our experiments. The fusion of curve aligning with backward–forward accelerations and DTW with vertical accelerations promotes authentication performances substantially and consistently. This fusion algorithm is tested repeatedly. Its mean and standard deviation of equal error rates are 0.794% and 0.696%, respectively, whereas among all presented non-fusion algorithms, the best one shows an EER of 3.03%. (paper)

  9. Progress in evaluation of human observer visual detection performance using the ROC curve approach

    International Nuclear Information System (INIS)

    Metz, C.E.; Starr, S.J.; Lusted, L.B.; Rossmann, K.

    1976-01-01

    The ROC approach to analysis of human observer detection performance as playing a key role in elucidation the relationships among the physical parameters of an imaging operation, the ability of a human observer to use the image to make decisions regarding the state of health or disease in a medical diagnostic situation, and the medical and social utility of those decisions, was studied. The conventional ROC curve describing observer performance in simple detection tasks can be used to predict observer performance in complex detection tasks. The conventional ROC curve thus provides a description of observer detection performance which is useful in situations more relevant clinically than those for which it is measured. Similar predictions regarding observer performance in identification and recognition tasks are currently being sought. The ROC curve can be used to relate signal detectability to various measures of the diagnostic and social benefit derived from a medical imaging procedure. These relationships provide a means for assessing the relative desirability of alternative diagnostic techniques and can be used to evaluate combinations of diagnostic studies

  10. Highly curved image sensors: a practical approach for improved optical performance.

    Science.gov (United States)

    Guenter, Brian; Joshi, Neel; Stoakley, Richard; Keefe, Andrew; Geary, Kevin; Freeman, Ryan; Hundley, Jake; Patterson, Pamela; Hammon, David; Herrera, Guillermo; Sherman, Elena; Nowak, Andrew; Schubert, Randall; Brewer, Peter; Yang, Louis; Mott, Russell; McKnight, Geoff

    2017-06-12

    The significant optical and size benefits of using a curved focal surface for imaging systems have been well studied yet never brought to market for lack of a high-quality, mass-producible, curved image sensor. In this work we demonstrate that commercial silicon CMOS image sensors can be thinned and formed into accurate, highly curved optical surfaces with undiminished functionality. Our key development is a pneumatic forming process that avoids rigid mechanical constraints and suppresses wrinkling instabilities. A combination of forming-mold design, pressure membrane elastic properties, and controlled friction forces enables us to gradually contact the die at the corners and smoothly press the sensor into a spherical shape. Allowing the die to slide into the concave target shape enables a threefold increase in the spherical curvature over prior approaches having mechanical constraints that resist deformation, and create a high-stress, stretch-dominated state. Our process creates a bridge between the high precision and low-cost but planar CMOS process, and ideal non-planar component shapes such as spherical imagers for improved optical systems. We demonstrate these curved sensors in prototype cameras with custom lenses, measuring exceptional resolution of 3220 line-widths per picture height at an aperture of f/1.2 and nearly 100% relative illumination across the field. Though we use a 1/2.3" format image sensor in this report, we also show this process is generally compatible with many state of the art imaging sensor formats. By example, we report photogrammetry test data for an APS-C sized silicon die formed to a 30° subtended spherical angle. These gains in sharpness and relative illumination enable a new generation of ultra-high performance, manufacturable, digital imaging systems for scientific, industrial, and artistic use.

  11. Dynamic energy conservation model REDUCE. Extension with experience curves, energy efficiency indicators and user's guide

    International Nuclear Information System (INIS)

    Uyterlinde, M.A.; Rijkers, F.A.M.

    1999-12-01

    The main objective of the energy conservation model REDUCE (Reduction of Energy Demand by Utilization of Conservation of Energy) is the evaluation of the effectiveness of economical, financial, institutional, and regulatory measures for improving the rational use of energy in end-use sectors. This report presents the results of additional model development activities, partly based on the first experiences in a previous project. Energy efficiency indicators have been added as an extra tool for output analysis in REDUCE. The methodology is described and some examples are given. The model has been extended with a method for modelling the effects of technical development on production costs, by means of an experience curve. Finally, the report provides a 'users guide', by describing in more detail the input data specification as well as all menus and buttons. 19 refs

  12. STRUCTURAL APPROACH TO THE MATHEMATICAL DESCRIPTION AND COMPUTER VISUALIZATION OF PLANE KINEMATIC CURVES FOR THE DISPLAY OF GEARS

    Directory of Open Access Journals (Sweden)

    Tatyana TRETYAK

    2018-05-01

    Full Text Available The structural approach stated in this paper allows to simulate the different plane kinematic curves without their concrete analytic equations. The summarized unified mapping system for rack gearing is used. The examples of plane kinematic curves received by the structural method on computer are adduced.

  13. Characterizing Synergistic Water and Energy Efficiency at the Residential Scale Using a Cost Abatement Curve Approach

    Science.gov (United States)

    Stillwell, A. S.; Chini, C. M.; Schreiber, K. L.; Barker, Z. A.

    2015-12-01

    Energy and water are two increasingly correlated resources. Electricity generation at thermoelectric power plants requires cooling such that large water withdrawal and consumption rates are associated with electricity consumption. Drinking water and wastewater treatment require significant electricity inputs to clean, disinfect, and pump water. Due to this energy-water nexus, energy efficiency measures might be a cost-effective approach to reducing water use and water efficiency measures might support energy savings as well. This research characterizes the cost-effectiveness of different efficiency approaches in households by quantifying the direct and indirect water and energy savings that could be realized through efficiency measures, such as low-flow fixtures, energy and water efficient appliances, distributed generation, and solar water heating. Potential energy and water savings from these efficiency measures was analyzed in a product-lifetime adjusted economic model comparing efficiency measures to conventional counterparts. Results were displayed as cost abatement curves indicating the most economical measures to implement for a target reduction in water and/or energy consumption. These cost abatement curves are useful in supporting market innovation and investment in residential-scale efficiency.

  14. Methods for extracting dose response curves from radiation therapy data. I. A unified approach

    International Nuclear Information System (INIS)

    Herring, D.F.

    1980-01-01

    This paper discusses an approach to fitting models to radiation therapy data in order to extract dose response curves for tumor local control and normal tissue damage. The approach is based on the method of maximum likelihood and is illustrated by several examples. A general linear logistic equation which leads to the Ellis nominal standard dose (NSD) equation is discussed; the fit of this equation to experimental data for mouse foot skin reactions produced by fractionated irradiation is described. A logistic equation based on the concept that normal tissue reactions are associated with the surviving fraction of cells is also discussed, and the fit of this equation to the same set of mouse foot skin reaction data is also described. These two examples illustrate the importance of choosing a model based on underlying mechanisms when one seeks to attach biological significance to a model's parameters

  15. INTEGRATED EXPERIENCE APPROACH TO LEARNING.

    Science.gov (United States)

    POSTLETHWAIT, S.N.; AND OTHERS

    THE USE OF AUDIOTUTORIAL TECHNIQUES FOR TEACHING INTRODUCTORY COLLEGE BOTANY IS DESCRIBED. SPECIFIC PRACTICES USED AT PURDUE UNIVERSITY TO ILLUSTRATE DIFFERENT FACETS OF THE APPROACH ARE ANALYZED. INCLUDED ARE INDEPENDENT STUDY SESSIONS, SMALL ASSEMBLY SESSIONS, GENERAL ASSEMBLY SESSIONS, AND HOME STUDY SESSIONS. ILLUSTRATIONS AND SPECIFICATIONS…

  16. A semiparametric separation curve approach for comparing correlated ROC data from multiple markers

    Science.gov (United States)

    Tang, Liansheng Larry; Zhou, Xiao-Hua

    2012-01-01

    In this article we propose a separation curve method to identify the range of false positive rates for which two ROC curves differ or one ROC curve is superior to the other. Our method is based on a general multivariate ROC curve model, including interaction terms between discrete covariates and false positive rates. It is applicable with most existing ROC curve models. Furthermore, we introduce a semiparametric least squares ROC estimator and apply the estimator to the separation curve method. We derive a sandwich estimator for the covariance matrix of the semiparametric estimator. We illustrate the application of our separation curve method through two real life examples. PMID:23074360

  17. Beyond the SCS curve number: A new stochastic spatial runoff approach

    Science.gov (United States)

    Bartlett, M. S., Jr.; Parolari, A.; McDonnell, J.; Porporato, A. M.

    2015-12-01

    The Soil Conservation Service curve number (SCS-CN) method is the standard approach in practice for predicting a storm event runoff response. It is popular because its low parametric complexity and ease of use. However, the SCS-CN method does not describe the spatial variability of runoff and is restricted to certain geographic regions and land use types. Here we present a general theory for extending the SCS-CN method. Our new theory accommodates different event based models derived from alternative rainfall-runoff mechanisms or distributions of watershed variables, which are the basis of different semi-distributed models such as VIC, PDM, and TOPMODEL. We introduce a parsimonious but flexible description where runoff is initiated by a pure threshold, i.e., saturation excess, that is complemented by fill and spill runoff behavior from areas of partial saturation. To facilitate event based runoff prediction, we derive simple equations for the fraction of the runoff source areas, the probability density function (PDF) describing runoff variability, and the corresponding average runoff value (a runoff curve analogous to the SCS-CN). The benefit of the theory is that it unites the SCS-CN method, VIC, PDM, and TOPMODEL as the same model type but with different assumptions for the spatial distribution of variables and the runoff mechanism. The new multiple runoff mechanism description for the SCS-CN enables runoff prediction in geographic regions and site runoff types previously misrepresented by the traditional SCS-CN method. In addition, we show that the VIC, PDM, and TOPMODEL runoff curves may be more suitable than the SCS-CN for different conditions. Lastly, we explore predictions of sediment and nutrient transport by applying the PDF describing runoff variability within our new framework.

  18. Not proper ROC curves as new tool for the analysis of differentially expressed genes in microarray experiments

    Directory of Open Access Journals (Sweden)

    Pistoia Vito

    2008-10-01

    Full Text Available Abstract Background Most microarray experiments are carried out with the purpose of identifying genes whose expression varies in relation with specific conditions or in response to environmental stimuli. In such studies, genes showing similar mean expression values between two or more groups are considered as not differentially expressed, even if hidden subclasses with different expression values may exist. In this paper we propose a new method for identifying differentially expressed genes, based on the area between the ROC curve and the rising diagonal (ABCR. ABCR represents a more general approach than the standard area under the ROC curve (AUC, because it can identify both proper (i.e., concave and not proper ROC curves (NPRC. In particular, NPRC may correspond to those genes that tend to escape standard selection methods. Results We assessed the performance of our method using data from a publicly available database of 4026 genes, including 14 normal B cell samples (NBC and 20 heterogeneous lymphomas (namely: 9 follicular lymphomas and 11 chronic lymphocytic leukemias. Moreover, NBC also included two sub-classes, i.e., 6 heavily stimulated and 8 slightly or not stimulated samples. We identified 1607 differentially expressed genes with an estimated False Discovery Rate of 15%. Among them, 16 corresponded to NPRC and all escaped standard selection procedures based on AUC and t statistics. Moreover, a simple inspection to the shape of such plots allowed to identify the two subclasses in either one class in 13 cases (81%. Conclusion NPRC represent a new useful tool for the analysis of microarray data.

  19. Calculation approaches for grid usage fees to influence the load curve in the distribution grid level

    International Nuclear Information System (INIS)

    Illing, Bjoern

    2014-01-01

    Dominated by the energy policy the decentralized German energy market is changing. One mature target of the government is to increase the contribution of renewable generation to the gross electricity consumption. In order to achieve this target disadvantages like an increased need for capacity management occurs. Load reduction and variable grid fees offer the grid operator solutions to realize capacity management by influencing the load profile. The evolution of the current grid fees towards more causality is required to adapt these approaches. Two calculation approaches are developed in this assignment. On the one hand multivariable grid fees keeping the current components demand and energy charge. Additional to the grid costs grid load dependent parameters like the amount of decentralized feed-ins, time and local circumstances as well as grid capacities are considered. On the other hand the grid fee flat-rate which represents a demand based model on a monthly level. Both approaches are designed to meet the criteria for future grid fees. By means of a case study the effects of the grid fees on the load profile at the low voltage grid is simulated. Thereby the consumption is represented by different behaviour models and the results are scaled at the benchmark grid area. The resulting load curve is analyzed concerning the effects of peak load reduction as well as the integration of renewable energy sources. Additionally the combined effect of grid fees and electricity tariffs is evaluated. Finally the work discusses the launching of grid fees in the tense atmosphere of politics, legislation and grid operation. Results of this work are two calculation approaches designed for grid operators to define the grid fees. Multivariable grid fees are based on the current calculation scheme. Hereby demand and energy charges are weighted by time, locational and load related dependencies. The grid fee flat-rate defines a limitation in demand extraction. Different demand levels

  20. The mapping approach in the path integral formalism applied to curve-crossing systems

    International Nuclear Information System (INIS)

    Novikov, Alexey; Kleinekathoefer, Ulrich; Schreiber, Michael

    2004-01-01

    The path integral formalism in a combined phase-space and coherent-state representation is applied to the problem of curve-crossing dynamics. The system of interest is described by two coupled one-dimensional harmonic potential energy surfaces interacting with a heat bath consisting of harmonic oscillators. The mapping approach is used to rewrite the Lagrangian function of the electronic part of the system. Using the Feynman-Vernon influence-functional method the bath is eliminated whereas the non-Gaussian part of the path integral is treated using the generating functional for the electronic trajectories. The dynamics of a Gaussian wave packet is analyzed along a one-dimensional reaction coordinate within a perturbative treatment for a small coordinate shift between the potential energy surfaces

  1. Analysis of Fuel Cell Markets in Japan and the US: Experience Curve Development and Cost Reduction Disaggregation

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Smith, Sarah J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sohn, Michael D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-07-15

    Fuel cells are both a longstanding and emerging technology for stationary and transportation applications, and their future use will likely be critical for the deep decarbonization of global energy systems. As we look into future applications, a key challenge for policy-makers and technology market forecasters who seek to track and/or accelerate their market adoption is the ability to forecast market costs of the fuel cells as technology innovations are incorporated into market products. Specifically, there is a need to estimate technology learning rates, which are rates of cost reduction versus production volume. Unfortunately, no literature exists for forecasting future learning rates for fuel cells. In this paper, we look retrospectively to estimate learning rates for two fuel cell deployment programs: (1) the micro-combined heat and power (CHP) program in Japan, and (2) the Self-Generation Incentive Program (SGIP) in California. These two examples have a relatively broad set of historical market data and thus provide an informative and international comparison of distinct fuel cell technologies and government deployment programs. We develop a generalized procedure for disaggregating experience-curve cost-reductions in order to disaggregate the Japanese fuel cell micro-CHP market into its constituent components, and we derive and present a range of learning rates that may explain observed market trends. Finally, we explore the differences in the technology development ecosystem and market conditions that may have contributed to the observed differences in cost reduction and draw policy observations for the market adoption of future fuel cell technologies. The scientific and policy contributions of this paper are the first comparative experience curve analysis of past fuel cell technologies in two distinct markets, and the first quantitative comparison of a detailed cost model of fuel cell systems with actual market data. The resulting approach is applicable to

  2. The Nordic Approach to the Experience Economy

    DEFF Research Database (Denmark)

    Bille, Trine

    This paper discusses the concept of the experience economy in a Nordic context and shows how the Nordic version of the concept has come about from a mix of three different approaches and theories. Besides, the Nordic definition links the experience economy closely with cultural activities...

  3. Thermal effect on water retention curve of bentonite: experiment and thermodynamic modeling

    International Nuclear Information System (INIS)

    Qin Bing; Chen Zhenghai; Sun Faxin; Liu Yuemiao; Wang Ju

    2012-01-01

    The thermal effects on water retention curve of GMZ bentonite were investigated experimentally and theoretically. Water retention tests were conducted on GMZ bentonite at five temperatures ranging from 20℃ to 100℃. Test results showed that the water retention capacity and the hysteresis of the water retention curve decreased with increasing temperature, and that the water retention curves at different temperatures were almost parallel to each other. Based on the thermodynamics of sorption, a model was established to describe the temperature influence on the water retention curve. The model was validated by comparing the model predictions and the test results. (authors)

  4. Method and Excel VBA Algorithm for Modeling Master Recession Curve Using Trigonometry Approach.

    Science.gov (United States)

    Posavec, Kristijan; Giacopetti, Marco; Materazzi, Marco; Birk, Steffen

    2017-11-01

    A new method was developed and implemented into an Excel Visual Basic for Applications (VBAs) algorithm utilizing trigonometry laws in an innovative way to overlap recession segments of time series and create master recession curves (MRCs). Based on a trigonometry approach, the algorithm horizontally translates succeeding recession segments of time series, placing their vertex, that is, the highest recorded value of each recession segment, directly onto the appropriate connection line defined by measurement points of a preceding recession segment. The new method and algorithm continues the development of methods and algorithms for the generation of MRC, where the first published method was based on a multiple linear/nonlinear regression model approach (Posavec et al. 2006). The newly developed trigonometry-based method was tested on real case study examples and compared with the previously published multiple linear/nonlinear regression model-based method. The results show that in some cases, that is, for some time series, the trigonometry-based method creates narrower overlaps of the recession segments, resulting in higher coefficients of determination R 2 , while in other cases the multiple linear/nonlinear regression model-based method remains superior. The Excel VBA algorithm for modeling MRC using the trigonometry approach is implemented into a spreadsheet tool (MRCTools v3.0 written by and available from Kristijan Posavec, Zagreb, Croatia) containing the previously published VBA algorithms for MRC generation and separation. All algorithms within the MRCTools v3.0 are open access and available free of charge, supporting the idea of running science on available, open, and free of charge software. © 2017, National Ground Water Association.

  5. Experience curve analysis on South Korean nuclear technology and comparative analysis with South Korean renewable technologies

    International Nuclear Information System (INIS)

    Kim, Dong Wook; Chang, Hyun Joon

    2012-01-01

    Increasing awareness on environmental damage and climate change has induced many nations to engage in green growth. South Korea, as one of the largest consumers of energy, is no exception and has shown its determination to pursue green growth in the future. In order to do so, South Korea plans to substitute fossil fuel with alternative sources in electricity generation. However, the key constraint to green growth is the high cost faced by renewable electricity generation. Fortunately, nuclear energy can serve as an economic alternative to fossil fuel. To achieve CO 2 emission reduction and faster economic growth, it is wise to analyze prospects of alternatives using experience curve framework. The results and industry background are consistent for nuclear technology, and the results suggest that nuclear should serve as the main substitute. Consideration of policy risk inherent in renewable also strengthens the argument. Renewable technologies, on the other hand, showed overstated learning capacity that is partially inconsistent with technological background. Nevertheless, the renewable (photovoltaic and fuel cell) should help nuclear marginally in substituting fossil fuel in South Korea's Electricity Generation. - Highlights: ► Progress ratios of renewable energy show great prospect. ► The policy risk is inherent in renewable and may overestimate its prospect. ► Nuclear sources are economic and less affected by policy risk. ► Fuel cell and photovoltaic should help nuclear marginally in green growth.

  6. Fluoroscopy Learning Curve in Hip Arthroscopy-A Single Surgeon's Experience.

    Science.gov (United States)

    Smith, Kevin M; Duplantier, Neil L; Crump, Kimbelyn H; Delgado, Domenica A; Sullivan, Stephanie L; McCulloch, Patrick C; Harris, Joshua D

    2017-10-01

    To determine if (1) absorbed radiation dose and (2) fluoroscopy time decreased with experience over the first 100 cases of a single surgeon's hip arthroscopy practice. Subjects who underwent hip arthroscopy for symptomatic femoroacetabular impingement and labral injury were eligible for analysis. Inclusion criteria included the first 100 subjects who underwent hip arthroscopy by a single surgeon (December 2013 to December 2014). Subject demographics, procedure details, fluoroscopy absorbed dose (milligray [mGy]), and time were recorded. Subjects were categorized by date of surgery to one of 4 possible groups (25 per group). One-way analysis of variance was used to determine if a significant difference in dose (mGy) or time was present between groups. Simple linear regression analysis was performed to determine the relation between case number and both radiation dose and fluoroscopy time. Subjects underwent labral repair (n = 93), cam osteoplasty (n = 90), and pincer acetabuloplasty (n = 65). There was a significant (P arthroscopy practice learning curve. Level IV, therapeutic, retrospective, noncomparative case series. Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  7. A new approach for determining phase response curves reveals that Purkinje cells can act as perfect integrators.

    Directory of Open Access Journals (Sweden)

    Elena Phoka

    2010-04-01

    Full Text Available Cerebellar Purkinje cells display complex intrinsic dynamics. They fire spontaneously, exhibit bistability, and via mutual network interactions are involved in the generation of high frequency oscillations and travelling waves of activity. To probe the dynamical properties of Purkinje cells we measured their phase response curves (PRCs. PRCs quantify the change in spike phase caused by a stimulus as a function of its temporal position within the interspike interval, and are widely used to predict neuronal responses to more complex stimulus patterns. Significant variability in the interspike interval during spontaneous firing can lead to PRCs with a low signal-to-noise ratio, requiring averaging over thousands of trials. We show using electrophysiological experiments and simulations that the PRC calculated in the traditional way by sampling the interspike interval with brief current pulses is biased. We introduce a corrected approach for calculating PRCs which eliminates this bias. Using our new approach, we show that Purkinje cell PRCs change qualitatively depending on the firing frequency of the cell. At high firing rates, Purkinje cells exhibit single-peaked, or monophasic PRCs. Surprisingly, at low firing rates, Purkinje cell PRCs are largely independent of phase, resembling PRCs of ideal non-leaky integrate-and-fire neurons. These results indicate that Purkinje cells can act as perfect integrators at low firing rates, and that the integration mode of Purkinje cells depends on their firing rate.

  8. Unified approach for estimating the probabilistic design S-N curves of three commonly used fatigue stress-life models

    International Nuclear Information System (INIS)

    Zhao Yongxiang; Wang Jinnuo; Gao Qing

    2001-01-01

    A unified approach, referred to as general maximum likelihood method, is presented for estimating probabilistic design S-N curves and their confidence bounds of the three commonly used fatigue stress-life models, namely three parameter, Langer and Basquin. The curves are described by a general form of mean and standard deviation S-N curves of the logarithm of fatigue life. Different from existent methods, i.e., the conventional method and the classical maximum likelihood method,present approach considers the statistical characteristics of whole test data. The parameters of the mean curve is firstly estimated by least square method and then, the parameters of the standard deviation curve is evaluated by mathematical programming method to be agreement with the maximum likelihood principle. Fit effects of the curves are assessed by fitted relation coefficient, total fitted standard error and the confidence bounds. Application to the virtual stress amplitude-crack initiation life data of a nuclear engineering material, Chinese 1Cr18Ni9Ti stainless steel pipe-weld metal, has indicated the validity of the approach to the S-N data where both S and N show the character of random variable. Practices to the two states of S-N data of Chinese 45 carbon steel notched specimens (k t = 2.0) have indicated the validity of present approach to the test results obtained respectively from group fatigue test and from maximum likelihood fatigue test. At the practices, it was revealed that in general the fit is best for the three-parameter model,slightly inferior for the Langer relation and poor for the Basquin equation. Relative to the existent methods, present approach has better fit. In addition, the possible non-conservative predictions of the existent methods, which are resulted from the influence of local statistical characteristics of the data, are also overcome by present approach

  9. Testing the Environmental Kuznets Curve Hypothesis for Biodiversity Risk in the US: A Spatial Econometric Approach

    Directory of Open Access Journals (Sweden)

    Robert P. Berrens

    2011-11-01

    Full Text Available This study investigates whether the environmental Kuznets curve (EKC relationship is supported for a measure of biodiversity risk and economic development across the United States (US. Using state-level data for all 48 contiguous states, biodiversity risk is measured using a Modified Index (MODEX. This index is an adaptation of a comprehensive National Biodiversity Risk Assessment Index. The MODEX differs from other measures in that it is takes into account the impact of human activities and conservation measures. The econometric approach includes corrections for spatial autocorrelation effects, which are present in the data. Modeling estimation results do not support the EKC hypothesis for biodiversity risk in the US. This finding is robust over ordinary least squares, spatial error, and spatial lag models, where the latter is shown to be the preferred model. Results from the spatial lag regression show that a 1% increase in human population density is associated with about a 0.19% increase in biodiversity risk. Spatial dependence in this case study explains 30% of the variation, as risk in one state spills over into adjoining states. From a policy perspective, this latter result supports the need for coordinated efforts at state and federal levels to address the problem of biodiversity loss.

  10. Retention and Curve Number Variability in a Small Agricultural Catchment: The Probabilistic Approach

    Directory of Open Access Journals (Sweden)

    Kazimierz Banasik

    2014-04-01

    Full Text Available The variability of the curve number (CN and the retention parameter (S of the Soil Conservation Service (SCS-CN method in a small agricultural, lowland watershed (23.4 km2 to the gauging station in central Poland has been assessed using the probabilistic approach: distribution fitting and confidence intervals (CIs. Empirical CNs and Ss were computed directly from recorded rainfall depths and direct runoff volumes. Two measures of the goodness of fit were used as selection criteria in the identification of the parent distribution function. The measures specified the generalized extreme value (GEV, normal and general logistic (GLO distributions for 100-CN and GLO, lognormal and GEV distributions for S. The characteristics estimated from theoretical distribution (median, quantiles were compared to the tabulated CN and to the antecedent runoff conditions of Hawkins and Hjelmfelt. The distribution fitting for the whole sample revealed a good agreement between the tabulated CN and the median and between the antecedent runoff conditions (ARCs of Hawkins and Hjelmfelt, which certified a good calibration of the model. However, the division of the CN sample due to heavy and moderate rainfall depths revealed a serious inconsistency between the parameters mentioned. This analysis proves that the application of the SCS-CN method should rely on deep insight into the probabilistic properties of CN and S.

  11. Histogram Curve Matching Approaches for Object-based Image Classification of Land Cover and Land Use

    Science.gov (United States)

    Toure, Sory I.; Stow, Douglas A.; Weeks, John R.; Kumar, Sunil

    2013-01-01

    The classification of image-objects is usually done using parametric statistical measures of central tendency and/or dispersion (e.g., mean or standard deviation). The objectives of this study were to analyze digital number histograms of image objects and evaluate classifications measures exploiting characteristic signatures of such histograms. Two histograms matching classifiers were evaluated and compared to the standard nearest neighbor to mean classifier. An ADS40 airborne multispectral image of San Diego, California was used for assessing the utility of curve matching classifiers in a geographic object-based image analysis (GEOBIA) approach. The classifications were performed with data sets having 0.5 m, 2.5 m, and 5 m spatial resolutions. Results show that histograms are reliable features for characterizing classes. Also, both histogram matching classifiers consistently performed better than the one based on the standard nearest neighbor to mean rule. The highest classification accuracies were produced with images having 2.5 m spatial resolution. PMID:24403648

  12. A multiresolution approach for the convergence acceleration of multivariate curve resolution methods.

    Science.gov (United States)

    Sawall, Mathias; Kubis, Christoph; Börner, Armin; Selent, Detlef; Neymeyr, Klaus

    2015-09-03

    Modern computerized spectroscopic instrumentation can result in high volumes of spectroscopic data. Such accurate measurements rise special computational challenges for multivariate curve resolution techniques since pure component factorizations are often solved via constrained minimization problems. The computational costs for these calculations rapidly grow with an increased time or frequency resolution of the spectral measurements. The key idea of this paper is to define for the given high-dimensional spectroscopic data a sequence of coarsened subproblems with reduced resolutions. The multiresolution algorithm first computes a pure component factorization for the coarsest problem with the lowest resolution. Then the factorization results are used as initial values for the next problem with a higher resolution. Good initial values result in a fast solution on the next refined level. This procedure is repeated and finally a factorization is determined for the highest level of resolution. The described multiresolution approach allows a considerable convergence acceleration. The computational procedure is analyzed and is tested for experimental spectroscopic data from the rhodium-catalyzed hydroformylation together with various soft and hard models. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Structural modeling of age specific fertility curves in Peninsular Malaysia: An approach of Lee Carter method

    Science.gov (United States)

    Hanafiah, Hazlenah; Jemain, Abdul Aziz

    2013-11-01

    In recent years, the study of fertility has been getting a lot of attention among research abroad following fear of deterioration of fertility led by the rapid economy development. Hence, this study examines the feasibility of developing fertility forecasts based on age structure. Lee Carter model (1992) is applied in this study as it is an established and widely used model in analysing demographic aspects. A singular value decomposition approach is incorporated with an ARIMA model to estimate age specific fertility rates in Peninsular Malaysia over the period 1958-2007. Residual plots is used to measure the goodness of fit of the model. Fertility index forecast using random walk drift is then utilised to predict the future age specific fertility. Results indicate that the proposed model provides a relatively good and reasonable data fitting. In addition, there is an apparent and continuous decline in age specific fertility curves in the next 10 years, particularly among mothers' in their early 20's and 40's. The study on the fertility is vital in order to maintain a balance between the population growth and the provision of facilities related resources.

  14. Application of the master curve approach to fracture mechanics characterisation of reactor pressure vessel steel

    International Nuclear Information System (INIS)

    Viehrig, Hans-Werner; Zurbuchen, Conrad; Kalkhof, Dietmar

    2010-06-01

    The paper presents results of a research project founded by the Swiss Federal Nuclear Inspectorate concerning the application of the Master Curve approach in nuclear reactor pressure vessels integrity assessment. The main focus is put on the applicability of pre-cracked 0.4T-SE(B) specimens with short cracks, the verification of transferability of MC reference temperatures T 0 from 0.4T thick specimens to larger specimens, ascertaining the influence of the specimen type and the test temperature on T 0 , investigation of the applicability of specimens with electroerosive notches for the fracture toughness testing, and the quantification of the loading rate and specimen type on T 0 . The test material is a forged ring of steel 22 NiMoCr 3-7 of the uncommissioned German pressurized water reactor Biblis C. SE(B) specimens with different overall sizes (specimen thickness B=0.4T, 0.8T, 1.6T, 3T, fatigue pre-cracked to a/W=0.5 and 20% side-grooved) have comparable T 0 . T 0 varies within the 1σ scatter band. The testing of C(T) specimens results in higher T 0 compared to SE(B) specimens. It can be stated that except for the lowest test temperature allowed by ASTM E1921-09a, the T 0 values evaluated with specimens tested at different test temperatures are consistent. The testing in the temperature range of T 0 ± 20 K is recommended because it gave the highest accuracy. Specimens with a/W=0.3 and a/W=0.5 crack length ratios yield comparable T 0 . The T 0 of EDM notched specimens lie 41 K up to 54 K below the T 0 of fatigue pre-cracked specimens. A significant influence of the loading rate on the MC T 0 was observed. The HSK AN 425 test procedure is a suitable method to evaluate dynamic MC tests. The reference temperature T 0 is eligible to define a reference temperature RT To for the ASME-KIC reference curve as recommended in the ASME Code Case N-629. An additional margin has to be defined for the specific type of transient to be considered in the RPV integrity assessment

  15. Analysis of diffusion paths for photovoltaic technology based on experience curves

    International Nuclear Information System (INIS)

    Poponi, Daniele

    2003-04-01

    This paper assesses the prospects for diffusion of photovoltaic (PV) technology for electricity generation in grid-connected systems. The analysis begins with the calculation of the break-even price of PV systems and modules, which is the price that can assure commercial viability without incentives or subsidies. The calculated average break-even price of PV systems for building-integrated applications is about US dollars 3.2/W p but can go up to about US dollars 4.5/W p in areas with very good solar irradiation and if a low real discount rate is applied. These are higher values than the break-even prices estimated in the literature to date. PV system break-even prices for intermediate load generation in utility-owned systems are also calculated, their average being about US dollars 1/W p The methodology of experience curves is used to predict what would be the different levels of cumulative world PV shipments required to reach the calculated break-even prices of PV systems, assuming different trends in the relationship between price and the increase in cumulative shipments. The years in which the break-even levels of cumulative shipments could be theoretically obtained are then calculated by considering different market growth rates. Photovoltaics could enter the niche of building-integrated applications without incentives in the first years of the next decade, provided that the PR is 80% and the average annual world market growth rate is at least 15%. The final part of the paper analyzes the niche markets or applications that seem promising for the diffusion of photovoltaics in the next few years (Author)

  16. The use of running integrated difference curves for analysing momentum distributions from positron annihilation experiments

    International Nuclear Information System (INIS)

    Coleman, C.F.

    1979-01-01

    In positron annihilation measurements it is often necessary to compare annihilation line shapes or angular distributions obtained from a single sample subjected to different experimental conditions, or from a range of samples subjected to different mechanical or metallurgical treatments. The difference of the normalised distributions provides a convenient, easily visualised, and comprehensive summary of the experimental results. Changes in the shape of these difference curves can be shown to arise only when within the material under examination competition occurs between different types of positron trap. Some of the factors affecting the shape of these difference curves are discussed in terms of trapping model concepts. By using the running integrals of the difference curves (RID curves) a representation is obtained which is very little affected by the number of channels spanning the line, provided that there are enough, leads naturally to an optimised determination of the line shape parameter S, leads to the definition of a number of parameters related to the shape of the difference curve and has well defined statistical properties. Examples of RID curves show the range of shapes encountered, shape changes associated with competition between different types of positron trap, and artefact shapes associated with rate dependent effects in the detector and electronics. (orig.) [de

  17. The Scandinavian Approach to the Experience Economy

    DEFF Research Database (Denmark)

    Bille, Trine

    2012-01-01

    This article discusses the concept of experience economy in a Scandinavian context and shows how the Scandinavian version of the concept has come about from a mix of three different approaches and theories. In the Scandinavian countries, the experience economy has been developed in a political...... context and is apparently a popular development policy for local government authorities and regions. The Scandinavian definition links the experience economy closely with cultural activities, and to the expectation of economic return and economic development. This article discusses the Scandinavian...

  18. Does Prior Laparoscopic and Open Surgery Experience Have Any Impact on Learning Curve in Transition to Robotic Surgery?

    Directory of Open Access Journals (Sweden)

    Cüneyt Adayener

    2016-12-01

    Full Text Available It has been 15 years since the Food And Drug Administration approved the Da Vinci® robotic surgery system. Robotic applications are being used extensively in urology, particularly in radical prostatectomy. Like all high-tech products, this system also has a high cost and a steep learning curve, therefore, preventing it from becoming widespread. There are various studies on the effect of open surgery or laparoscopy experience on the learning curve of robotic surgery. Analyzing these interactions well will provide valuable information on making the training period of robotic system more efficient.

  19. Correlation between 2D and 3D flow curve modelling of DP steels using a microstructure-based RVE approach

    International Nuclear Information System (INIS)

    Ramazani, A.; Mukherjee, K.; Quade, H.; Prahl, U.; Bleck, W.

    2013-01-01

    A microstructure-based approach by means of representative volume elements (RVEs) is employed to evaluate the flow curve of DP steels using virtual tensile tests. Microstructures with different martensite fractions and morphologies are studied in two- and three-dimensional approaches. Micro sections of DP microstructures with various amounts of martensite have been converted to 2D RVEs, while 3D RVEs were constructed statistically with randomly distributed phases. A dislocation-based model is used to describe the flow curve of each ferrite and martensite phase separately as a function of carbon partitioning and microstructural features. Numerical tensile tests of RVE were carried out using the ABAQUS/Standard code to predict the flow behaviour of DP steels. It is observed that 2D plane strain modelling gives an underpredicted flow curve for DP steels, while the 3D modelling gives a quantitatively reasonable description of flow curve in comparison to the experimental data. In this work, a von Mises stress correlation factor σ 3D /σ 2D has been identified to compare the predicted flow curves of these two dimensionalities showing a third order polynomial relation with respect to martensite fraction and a second order polynomial relation with respect to equivalent plastic strain, respectively. The quantification of this polynomial correlation factor is performed based on laboratory-annealed DP600 chemistry with varying martensite content and it is validated for industrially produced DP qualities with various chemistry, strength level and martensite fraction.

  20. Accuracy of progress ratios determined from experience curves: the case of photovoltaic technology development

    NARCIS (Netherlands)

    van Sark, W.G.J.H.M.|info:eu-repo/dai/nl/074628526; Alsema, E.A.|info:eu-repo/dai/nl/073416258; Junginger, H.M.|info:eu-repo/dai/nl/202130703; de Moor, H.H.C.; Schaeffer, G.J.

    2008-01-01

    Learning curves are extensively used in policy and scenario studies. Progress ratios (PRs) are derived from historical data and are used for forecasting cost development of many technologies, including photovoltaics (PV). Forecasts are highly sensitive to uncertainties in the PR. A PR usually is

  1. More basic approach to the analysis of multiple specimen R-curves for determination of J/sub c/

    International Nuclear Information System (INIS)

    Carlson, K.W.; Williams, J.A.

    1980-02-01

    Multiple specimen J-R curves were developed for groups of 1T compact specimens with different a/W values and depth of side grooving. The purpose of this investigation was to determine J/sub c/ (J at onset of crack extension) for each group. Judicious selection of points on the load versus load-line deflection record at which to unload and heat tint specimens permitted direct observation of approximate onset of crack extension. It was found that the present recommended procedure for determining J/sub c/ from multiple specimen R-curves, which is being considered for standardization, consistently yielded nonconservative J/sub c/ values. A more basic approach to analyzing multiple specimen R-curves is presented, applied, and discussed. This analysis determined J/sub c/ values that closely corresponded to actual observed onset of crack extension

  2. Use of regionalisation approach to develop fire frequency curves for Victoria, Australia

    Science.gov (United States)

    Khastagir, Anirban; Jayasuriya, Niranjali; Bhuyian, Muhammed A.

    2017-11-01

    It is important to perform fire frequency analysis to obtain fire frequency curves (FFC) based on fire intensity at different parts of Victoria. In this paper fire frequency curves (FFCs) were derived based on forest fire danger index (FFDI). FFDI is a measure related to fire initiation, spreading speed and containment difficulty. The mean temperature (T), relative humidity (RH) and areal extent of open water (LC2) during summer months (Dec-Feb) were identified as the most important parameters for assessing the risk of occurrence of bushfire. Based on these parameters, Andrews' curve equation was applied to 40 selected meteorological stations to identify homogenous stations to form unique clusters. A methodology using peak FFDI from cluster averaged FFDIs was developed by applying Log Pearson Type III (LPIII) distribution to generate FFCs. A total of nine homogeneous clusters across Victoria were identified, and subsequently their FFC's were developed in order to estimate the regionalised fire occurrence characteristics.

  3. An assessment of mode-coupling and falling-friction mechanisms in railway curve squeal through a simplified approach

    Science.gov (United States)

    Ding, Bo; Squicciarini, Giacomo; Thompson, David; Corradi, Roberto

    2018-06-01

    Curve squeal is one of the most annoying types of noise caused by the railway system. It usually occurs when a train or tram is running around tight curves. Although this phenomenon has been studied for many years, the generation mechanism is still the subject of controversy and not fully understood. A negative slope in the friction curve under full sliding has been considered to be the main cause of curve squeal for a long time but more recently mode coupling has been demonstrated to be another possible explanation. Mode coupling relies on the inclusion of both the lateral and vertical dynamics at the contact and an exchange of energy occurs between the normal and the axial directions. The purpose of this paper is to assess the role of the mode-coupling and falling-friction mechanisms in curve squeal through the use of a simple approach based on practical parameter values representative of an actual situation. A tramway wheel is adopted to study the effect of the adhesion coefficient, the lateral contact position, the contact angle and the damping ratio. Cases corresponding to both inner and outer wheels in the curve are considered and it is shown that there are situations in which both wheels can squeal due to mode coupling. Additionally, a negative slope is introduced in the friction curve while keeping active the vertical dynamics in order to analyse both mechanisms together. It is shown that, in the presence of mode coupling, the squealing frequency can differ from the natural frequency of either of the coupled wheel modes. Moreover, a phase difference between wheel vibration in the vertical and lateral directions is observed as a characteristic of mode coupling. For both these features a qualitative comparison is shown with field measurements which show the same behaviour.

  4. Urban Concentration and Spatial Allocation of Rents from natural resources. A Zipf's Curve Approach

    Directory of Open Access Journals (Sweden)

    Tomaz Ponce Dentinho

    2017-10-01

    Full Text Available This paper aims at demonstrating how countries' dependency on natural resources plays a crucial role in urban concentration. The Zipf's Curve Elasticity is estimated for a group of countries and related to a set of indicators of unilateral transferences. Results show that in comparison to others, countries with higher urban concentration explained by higher Zipf's Curve Elasticity have a higher percentage of income coming from natural resources and education expenditures whereas public spending in health and outflow of Foreign Direct Investment seem to have spatial redistribution effects. Summing up, there are signs that the spatial allocation of property rights over natural resources and related rents influences urban concentration.

  5. The Forecasting Power of the Yield Curve, a Supervised Factor Model Approach

    DEFF Research Database (Denmark)

    Boldrini, Lorenzo; Hillebrand, Eric Tobias

    loadings have the Nelson and Siegel (1987) structure and we consider one forecast target at a time. We compare the forecasting performance of our specification to benchmark models such as principal components regression, partial least squares, and ARMA(p,q) processes. We use the yield curve data from G...

  6. Estimating water use of mature pecan orchards: A six stage crop growth curve approach

    CSIR Research Space (South Africa)

    Ibraimo, NA

    2016-11-01

    Full Text Available previous study in New Mexico, revealed that a six stage crop coefficient curve should be considered for pecans, together with higher mid-season crop coefficient (K(subc)) values for mature orchards. More accurate estimates of monthly ET for mature pecan...

  7. Learning from the Sun. Analysis of the use of experience curves for energy policy purposes. The case of photovoltaic power. Final report of the Photex project

    International Nuclear Information System (INIS)

    Schaeffer, G.J.; Seebregts, A.J.; Beurskens, L.W.M.; De Moor, H.H.C.; Alsema, E.; Sark, W.; Durstewicz, M.; Perrin, M.; Boulanger, P.; Laukamp, H.; Zuccaro, C.

    2004-08-01

    Since the 1990s energy policy scientists have started to explore the possibilities of using the experience curve approach for energy policy making. The concept of the experience curve is simple, at least in principle. It states that, for every doubling of cumulative produced capacity of a product or technology, the cost for making it declines with a fixed percentage (learning rate). Historical statistical analysis can be used to define this percentage. Extrapolating the trend thus found, into the future will then give relevant information about future cost developments and will also give information how much 'learning money' will be needed to get to the break-even point. The Photex project used the development of solar PV as a case to further explore this approach, and also to deduce lessons for PV policy. Other aims were to look at learning rates of the different components of PV-systems and to combine the experience curve analyses with bottom-up engineering studies. The main conclusion with regard to the use of experience curves for energy policy making is that this is an interesting approach, but that such an analysis should be done with much care. For the historical analysis the availability of reliable and firm data is essential. As cost data often are not available, price data could be used as a proxy, as long as sufficient long time ranges are used. Also, the analyst should take care he considers the right learning system boundaries. Furthermore the number of years to be included in the statistical analysis should at least be 10 years and this period sample should not over-represent stable price periods or periods of steep price decline. If possible, data uncertainties should be taken into account as well. An interesting finding was that, at least in the case of PV, the learning rate is not a constant, but can vary over time. In the case of PV it improved from 20% to 23%. Extrapolations into the future should take uncertainties into account and always be

  8. Microcanonical Monte Carlo approach for computing melting curves by atomistic simulations

    OpenAIRE

    Davis, Sergio; Gutiérrez, Gonzalo

    2017-01-01

    We report microcanonical Monte Carlo simulations of melting and superheating of a generic, Lennard-Jones system starting from the crystalline phase. The isochoric curve, the melting temperature $T_m$ and the critical superheating temperature $T_{LS}$ obtained are in close agreement (well within the microcanonical temperature fluctuations) with standard molecular dynamics one-phase and two-phase methods. These results validate the use of microcanonical Monte Carlo to compute melting points, a ...

  9. From Experiment to Theory: What Can We Learn from Growth Curves?

    Science.gov (United States)

    Kareva, Irina; Karev, Georgy

    2018-01-01

    Finding an appropriate functional form to describe population growth based on key properties of a described system allows making justified predictions about future population development. This information can be of vital importance in all areas of research, ranging from cell growth to global demography. Here, we use this connection between theory and observation to pose the following question: what can we infer about intrinsic properties of a population (i.e., degree of heterogeneity, or dependence on external resources) based on which growth function best fits its growth dynamics? We investigate several nonstandard classes of multi-phase growth curves that capture different stages of population growth; these models include hyperbolic-exponential, exponential-linear, exponential-linear-saturation growth patterns. The constructed models account explicitly for the process of natural selection within inhomogeneous populations. Based on the underlying hypotheses for each of the models, we identify whether the population that it best fits by a particular curve is more likely to be homogeneous or heterogeneous, grow in a density-dependent or frequency-dependent manner, and whether it depends on external resources during any or all stages of its development. We apply these predictions to cancer cell growth and demographic data obtained from the literature. Our theory, if confirmed, can provide an additional biomarker and a predictive tool to complement experimental research.

  10. The N-shaped environmental Kuznets curve: an empirical evaluation using a panel quantile regression approach.

    Science.gov (United States)

    Allard, Alexandra; Takman, Johanna; Uddin, Gazi Salah; Ahmed, Ali

    2018-02-01

    We evaluate the N-shaped environmental Kuznets curve (EKC) using panel quantile regression analysis. We investigate the relationship between CO 2 emissions and GDP per capita for 74 countries over the period of 1994-2012. We include additional explanatory variables, such as renewable energy consumption, technological development, trade, and institutional quality. We find evidence for the N-shaped EKC in all income groups, except for the upper-middle-income countries. Heterogeneous characteristics are, however, observed over the N-shaped EKC. Finally, we find a negative relationship between renewable energy consumption and CO 2 emissions, which highlights the importance of promoting greener energy in order to combat global warming.

  11. A note on the environmental Kuznets curve for CO2: A pooled mean group approach

    International Nuclear Information System (INIS)

    Iwata, Hiroki; Okada, Keisuke; Samreth, Sovannroeun

    2011-01-01

    This paper investigates whether the environmental Kuznets curve (EKC) hypothesis for CO 2 emissions is satisfied using the panel data of 28 countries by taking nuclear energy into account. Using the pooled mean group (PMG) estimation method, our main results indicate that (1) the impacts of nuclear energy on CO 2 emissions are significantly negative, (2) CO 2 emissions actually increase monotonically within the sample period in all cases: the full sample, OECD countries, and non-OECD countries, and (3) the growth rate in CO 2 emissions with income is decreasing in OECD countries and increasing in non-OECD countries.

  12. Growth curves of clients' emotional experience and their association with emotion regulation and symptoms.

    Science.gov (United States)

    Fisher, Hadar; Atzil-Slonim, Dana; Bar-Kalifa, Eran; Rafaeli, Eshkol; Peri, Tuvia

    2017-12-06

    Emotional experience during psychotherapy is considered a core mechanism of change. Yet the sheer experience itself may not necessarily be beneficial; instead, the trajectories of emotional experience need to be explored as possible predictors of treatment outcomes. This study investigated whether clients' pre-treatment levels of emotion regulation and symptoms predicted patterns of session-to-session change in emotional experience. We also explored which patterns better predict clients' improvement in emotion regulation and symptoms from pre- to post treatment. One-hundred and seven clients undergoing psychodynamic psychotherapy completed questionnaires on their symptoms and emotion regulation at pre- and post- treatment. They also reported their level of emotional experience at the end of each session. Pre-treatment symptoms and difficulties in emotion regulation predicted greater instability in emotional experience. Higher mean levels of emotional experience during treatment were associated with an improvement in emotion regulation, and greater stability during treatment was associated with improvement in emotion regulation and symptoms. These findings lend weight to the idea that experiencing emotion in the therapeutic environment has significant implications for clients' ability to manage their emotions outside the session. However, emotions experienced in an unstable manner within therapy are associated with poorer outcomes. Clinical and methodological significance of this article: Therapists can benefit from observing the patterns and not only the level of their clients' emotional experiences. The identification of clients' difficulties early in treatment may help therapists guide clients through the delicate process of carefully attending to their emotions.

  13. A computational approach for functional mapping of quantitative trait loci that regulate thermal performance curves.

    Directory of Open Access Journals (Sweden)

    John Stephen Yap

    2007-06-01

    Full Text Available Whether and how thermal reaction norm is under genetic control is fundamental to understand the mechanistic basis of adaptation to novel thermal environments. However, the genetic study of thermal reaction norm is difficult because it is often expressed as a continuous function or curve. Here we derive a statistical model for dissecting thermal performance curves into individual quantitative trait loci (QTL with the aid of a genetic linkage map. The model is constructed within the maximum likelihood context and implemented with the EM algorithm. It integrates the biological principle of responses to temperature into a framework for genetic mapping through rigorous mathematical functions established to describe the pattern and shape of thermal reaction norms. The biological advantages of the model lie in the decomposition of the genetic causes for thermal reaction norm into its biologically interpretable modes, such as hotter-colder, faster-slower and generalist-specialist, as well as the formulation of a series of hypotheses at the interface between genetic actions/interactions and temperature-dependent sensitivity. The model is also meritorious in statistics because the precision of parameter estimation and power of QTLdetection can be increased by modeling the mean-covariance structure with a small set of parameters. The results from simulation studies suggest that the model displays favorable statistical properties and can be robust in practical genetic applications. The model provides a conceptual platform for testing many ecologically relevant hypotheses regarding organismic adaptation within the Eco-Devo paradigm.

  14. An economic perspective on experience curves and dynamic economies in renewable energy technologies

    International Nuclear Information System (INIS)

    Papineau, Maya

    2006-01-01

    This paper analyzes dynamic economies in renewable energy technologies. The paper has two contributions. The first is to test the robustness of experience in solar photovoltaic, solar thermal and wind energy to the addition of an explicit time trend, which has been done in experience studies for other industries, but not for renewable energy technologies. Estimation is carried out on the assumption that cumulative capacity, industry production, average firm production, and electricity generation affect experience and thus the fall in price. The second contribution is to test the impact of R and D on price reduction. In general cumulative experience is found to be highly statistically significant when estimated alone, and highly statistically insignificant when time is added to the model. The effect of R and D is small and statistically significant in solar photovoltaic technology and statistically insignificant in solar thermal and wind technologies

  15. Experiments in nonlinear dynamics using control-based continuation: Tracking stable and unstable response curves

    DEFF Research Database (Denmark)

    Bureau, Emil; Schilder, Frank; Santos, Ilmar

    2014-01-01

    We show how to implement control-based continuation in a nonlinear experiment using existing and freely available software. We demonstrate that it is possible to track the complete frequency response, including the unstable branches, for a harmonically forced impact oscillator.......We show how to implement control-based continuation in a nonlinear experiment using existing and freely available software. We demonstrate that it is possible to track the complete frequency response, including the unstable branches, for a harmonically forced impact oscillator....

  16. Authentication of virgin olive oil by a novel curve resolution approach combined with visible spectroscopy.

    Science.gov (United States)

    Ferreiro-González, Marta; Barbero, Gerardo F; Álvarez, José A; Ruiz, Antonio; Palma, Miguel; Ayuso, Jesús

    2017-04-01

    Adulteration of olive oil is not only a major economic fraud but can also have major health implications for consumers. In this study, a combination of visible spectroscopy with a novel multivariate curve resolution method (CR), principal component analysis (PCA) and linear discriminant analysis (LDA) is proposed for the authentication of virgin olive oil (VOO) samples. VOOs are well-known products with the typical properties of a two-component system due to the two main groups of compounds that contribute to the visible spectra (chlorophylls and carotenoids). Application of the proposed CR method to VOO samples provided the two pure-component spectra for the aforementioned families of compounds. A correlation study of the real spectra and the resolved component spectra was carried out for different types of oil samples (n=118). LDA using the correlation coefficients as variables to discriminate samples allowed the authentication of 95% of virgin olive oil samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Determination of performance degradation of a marine diesel engine by using curve based approach

    International Nuclear Information System (INIS)

    Kökkülünk, Görkem; Parlak, Adnan; Erdem, Hasan Hüseyin

    2016-01-01

    Highlights: • Mathematical model was developed for a marine diesel engine. • Measurements were taken from Main Engine of M/V Ince Inebolu. • The model was validated for the marine diesel engine. • Curve Based Method was performed to evaluate the performance. • Degradation values of a marine diesel engine were found for power and SFC. - Abstract: Nowadays, energy efficiency measures on ships are the top priority topic for the maritime sector. One of the important key parameters of energy efficiency is to find the useful tool to improve the energy efficiency. There are two steps to improve the energy efficiency on ships: Measurement and Evaluation of performance of main fuel consumers. Performance evaluation is the method that evaluates how much the performance changes owing to engine component degradation which cause to reduce the performance due to wear, fouling, mechanical problems, etc. In this study, zero dimensional two zone combustion model is developed and validated for two stroke marine diesel engine (MITSUI MAN B&W 6S50MC). The measurements are taken from a real ship named M/V Ince Inebolu by the research team during the normal operation of the main engine in the region of the Marmara Sea. To evaluate the performance, “Curve based method” is used to calculate the total performance degradation. This total degradation is classified as parameters of compression pressure, injection timing, injection pressure, scavenge air temperature and scavenge air pressure by means of developed mathematical model. In conclusion, the total degradation of the applied ship is found as 620 kW by power and 26.74 g/kW h by specific fuel consumption.

  18. Modelling small scale infiltration experiments into bore cores of crystalline rock and break-through curves

    International Nuclear Information System (INIS)

    Hadermann, J.; Jakob, A.

    1987-04-01

    Uranium infiltration experiments for small samples of crystalline rock have been used to model radionuclide transport. The theory, taking into account advection and dispersion in water conducting zones, matrix diffusion out of these, and sorption, contains four independent parameters. It turns out, that the physical variables extracted from those of the best-fit parameters are consistent with values from literature and independent measurements. Moreover, the model results seem to differentiate between various geometries for the water conducting zones. Alpha-autoradiographies corroborate this result. A sensitivity analysis allows for a judgement on parameter dependences. Finally some proposals for further experiments are made. (author)

  19. Navigation and flight director guidance for the NASA/FAA helicopter MLS curved approach flight test program

    Science.gov (United States)

    Phatak, A. V.; Lee, M. G.

    1985-01-01

    The navigation and flight director guidance systems implemented in the NASA/FAA helicopter microwave landing system (MLS) curved approach flight test program is described. Flight test were conducted at the U.S. Navy's Crows Landing facility, using the NASA Ames UH-lH helicopter equipped with the V/STOLAND avionics system. The purpose of these tests was to investigate the feasibility of flying complex, curved and descending approaches to a landing using MLS flight director guidance. A description of the navigation aids used, the avionics system, cockpit instrumentation and on-board navigation equipment used for the flight test is provided. Three generic reference flight paths were developed and flown during the test. They were as follows: U-Turn, S-turn and Straight-In flight profiles. These profiles and their geometries are described in detail. A 3-cue flight director was implemented on the helicopter. A description of the formulation and implementation of the flight director laws is also presented. Performance data and analysis is presented for one pilot conducting the flight director approaches.

  20. Calibration of a Fusion Experiment to Investigate the Nuclear Caloric Curve

    Science.gov (United States)

    Keeler, Ashleigh

    2017-09-01

    In order to investigate the nuclear equation of state (EoS), the relation between two thermodynamic quantities can be examined. The correlation between the temperature and excitation energy of a nucleus, also known as the caloric curve, has been previously observed in peripheral heavy-ion collisions to exhibit a dependence on the neutron-proton asymmetry. To further investigate this result, fusion reactions (78Kr + 12C and 86Kr + 12C) were measured; the beam energy was varied in the range 15-35 MeV/u in order to vary the excitation energy. The light charged particles (LCPs) evaporated from the compound nucleus were measured in the Si-CsI(TI)/PD detector array FAUST (Forward Array Using Silicon Technology). The LCPs carry information about the temperature. The calibration of FAUST will be described in this presentation. The silicon detectors have resistive surfaces in perpendicular directions to allow position measurement of the LCP's to better than 200 um. The resistive nature requires a position-dependent correction to the energy calibration to take full advantage of the energy resolution. The momentum is calculated from the energy of these particles, and their position on the detectors. A parameterized formula based on the Bethe-Bloch equation was used to straighten the particle identification (PID) lines measured with the dE-E technique. The energy calibration of the CsI detectors is based on the silicon detector energy calibration and the PID. A precision slotted mask enables the relative positions of the detectors to be determined. DOE Grant: DE-FG02-93ER40773 and REU Grant: PHY - 1659847.

  1. Interferometric windows characterization up to 450 K for shock wave experiments: Hugoniot curves and refractive index

    Directory of Open Access Journals (Sweden)

    Godefroit J.-L.

    2012-08-01

    Full Text Available Conventional shock wave experiments need interferometric windows in order to determine the equation of state of a large variety of metals. Lithium fluoride (LiF and sapphire are extensively used for that purpose because their optical transparencies enable the optical diagnostics at interfaces under a given range of shock pressure. In order to simulate and analyse the experiments it is necessary to gather a correct knowledge of the optical and mechanical properties of these windows. Therefore, our window supplies are systematically characterized and an experimental campaign under shock loading is conducted. Our preliminary work on LiF windows at 532 nm is in good agreement with literature data at room temperature and the new characterization at 450 K enables a better interpretation of our preheated target experiments. It confirms the predominant effect of density on optical properties under pressure and temperature. The present work demonstrates that the initial density determination is a key point and that the uncertainties need to be improved. For that purpose, complementary experiments are conducted on LiF windows with simplified target designs and enriched diagnostics, coupling VISAR (532 nm and PdV (1550 nm diagnostics. Furthermore, a similar campaign is conducted on sapphire windows with symmetric impact configuration.

  2. An alternative approach to calculating Area-Under-the-Curve (AUC) in delay discounting research.

    Science.gov (United States)

    Borges, Allison M; Kuang, Jinyi; Milhorn, Hannah; Yi, Richard

    2016-09-01

    Applied to delay discounting data, Area-Under-the-Curve (AUC) provides an atheoretical index of the rate of delay discounting. The conventional method of calculating AUC, by summing the areas of the trapezoids formed by successive delay-indifference point pairings, does not account for the fact that most delay discounting tasks scale delay pseudoexponentially, that is, time intervals between delays typically get larger as delays get longer. This results in a disproportionate contribution of indifference points at long delays to the total AUC, with minimal contribution from indifference points at short delays. We propose two modifications that correct for this imbalance via a base-10 logarithmic transformation and an ordinal scaling transformation of delays. These newly proposed indices of discounting, AUClog d and AUCor d, address the limitation of AUC while preserving a primary strength (remaining atheoretical). Re-examination of previously published data provides empirical support for both AUClog d and AUCor d . Thus, we believe theoretical and empirical arguments favor these methods as the preferred atheoretical indices of delay discounting. © 2016 Society for the Experimental Analysis of Behavior.

  3. Longitudinal associations between exercise identity and exercise motivation: A multilevel growth curve model approach.

    Science.gov (United States)

    Ntoumanis, N; Stenling, A; Thøgersen-Ntoumani, C; Vlachopoulos, S; Lindwall, M; Gucciardi, D F; Tsakonitis, C

    2018-02-01

    Past work linking exercise identity and exercise motivation has been cross-sectional. This is the first study to model the relations between different types of exercise identity and exercise motivation longitudinally. Understanding the dynamic associations between these sets of variables has implications for theory development and applied research. This was a longitudinal survey study. Participants were 180 exercisers (79 men, 101 women) from Greece, who were recruited from fitness centers and were asked to complete questionnaires assessing exercise identity (exercise beliefs and role-identity) and exercise motivation (intrinsic, identified, introjected, external motivation, and amotivation) three times within a 6 month period. Multilevel growth curve modeling examined the role of motivational regulations as within- and between-level predictors of exercise identity, and a model in which exercise identity predicted exercise motivation at the within- and between-person levels. Results showed that within-person changes in intrinsic motivation, introjected, and identified regulations were positively and reciprocally related to within-person changes in exercise beliefs; intrinsic motivation was also a positive predictor of within-person changes in role-identity but not vice versa. Between-person differences in the means of predictor variables were predictive of initial levels and average rates of change in the outcome variables. The findings show support to the proposition that a strong exercise identity (particularly exercise beliefs) can foster motivation for behaviors that reinforce this identity. We also demonstrate that such relations can be reciprocal overtime and can depend on the type of motivation in question as well as between-person differences in absolute levels of these variables. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. An hermeneutic approach to studying the nature of wilderness experiences

    Science.gov (United States)

    Michael E. Patterson; Alan E. Watson; Daniel R. Williams; Joseph R. Roggenbuck

    1998-01-01

    The most prevalent approach to understanding recreation experiences in resource management has been a motivational research program that views satisfaction as an appropriate indicator of experience quality. This research explores a different approach to studying the quality of recreation experiences. Rather than viewing recreation experiences as a linear sequence of...

  5. Industry-Cost-Curve Approach for Modeling the Environmental Impact of Introducing New Technologies in Life Cycle Assessment.

    Science.gov (United States)

    Kätelhön, Arne; von der Assen, Niklas; Suh, Sangwon; Jung, Johannes; Bardow, André

    2015-07-07

    The environmental costs and benefits of introducing a new technology depend not only on the technology itself, but also on the responses of the market where substitution or displacement of competing technologies may occur. An internationally accepted method taking both technological and market-mediated effects into account, however, is still lacking in life cycle assessment (LCA). For the introduction of a new technology, we here present a new approach for modeling the environmental impacts within the framework of LCA. Our approach is motivated by consequential life cycle assessment (CLCA) and aims to contribute to the discussion on how to operationalize consequential thinking in LCA practice. In our approach, we focus on new technologies producing homogeneous products such as chemicals or raw materials. We employ the industry cost-curve (ICC) for modeling market-mediated effects. Thereby, we can determine substitution effects at a level of granularity sufficient to distinguish between competing technologies. In our approach, a new technology alters the ICC potentially replacing the highest-cost producer(s). The technologies that remain competitive after the new technology's introduction determine the new environmental impact profile of the product. We apply our approach in a case study on a new technology for chlor-alkali electrolysis to be introduced in Germany.

  6. Analysis of the learning curve for peroral endoscopic myotomy for esophageal achalasia: Single-center, two-operator experience.

    Science.gov (United States)

    Lv, Houning; Zhao, Ningning; Zheng, Zhongqing; Wang, Tao; Yang, Fang; Jiang, Xihui; Lin, Lin; Sun, Chao; Wang, Bangmao

    2017-05-01

    Peroral endoscopic myotomy (POEM) has emerged as an advanced technique for the treatment of achalasia, and defining the learning curve is mandatory. From August 2011 to June 2014, two operators in our institution (A&B) carried out POEM on 35 and 33 consecutive patients, respectively. Moving average and cumulative sum (CUSUM) methods were used to analyze the POEM learning curve for corrected operative time (cOT), referring to duration of per centimeter myotomy. Additionally, perioperative outcomes were compared among distinct learning curve phases. Using the moving average method, cOT reached a plateau at the 29th case and at the 24th case for operators A and B, respectively. CUSUM analysis identified three phases: initial learning period (Phase 1), efficiency period (Phase 2) and mastery period (Phase 3). The relatively smooth state in the CUSUM graph occurred at the 26th case and at the 24th case for operators A and B, respectively. Mean cOT of distinct phases for operator A were 8.32, 5.20 and 3.97 min, whereas they were 5.99, 3.06 and 3.75 min for operator B, respectively. Eckardt score and lower esophageal sphincter pressure significantly decreased during the 1-year follow-up period. Data were comparable regarding patient characteristics and perioperative outcomes. This single-center study demonstrated that expert endoscopists with experience in esophageal endoscopic submucosal dissection reached a plateau in learning of POEM after approximately 25 cases. © 2016 Japan Gastroenterological Endoscopy Society.

  7. Using Data-Mining Approaches for Wind Turbine Power Curve Monitoring: A Comparative Study

    DEFF Research Database (Denmark)

    Schlechtingen, Meik; Santos, Ilmar; Achiche, Sofiane

    2013-01-01

    are built and their performance compared against literature. Recently developed adaptive neuro-fuzzy-interference system models are set up and their performance compared with the other models, using the same data. Literature models often neglect the influence of the ambient temperature and the wind...... direction. The ambient temperature can influence the power output up to 20%. Nearby obstacles can lower the power output for certain wind directions. The approaches proposed in literature and the ANFIS models are compared by using wind speed only and two additional inputs. The comparison is based...

  8. A learning curve approach to projecting cost and performance for photovoltaic technologies

    Science.gov (United States)

    Cody, George D.; Tiedje, Thomas

    1997-04-01

    The current cost of electricity generated by PV power is still extremely high with respect to power supplied by the utility grid, and there remain questions as to whether PV power can ever be competitive with electricity generated by fossil fuels. An objective approach to this important question was given in a previous paper by the authors which introduced analytical tools to define and project the technical/economic status of PV power from 1988 through the year 2010. In this paper, we apply these same tools to update the conclusions of our earlier study in the context of recent announcements by Amoco/Enron-Solarex of projected sales of PV power at rates significantly less than the US utility average.

  9. Learning curve approach to projecting cost and performance for photovoltaic technologies

    Science.gov (United States)

    Cody, George D.; Tiedje, Thomas

    1997-10-01

    The current cost of electricity generated by PV power is still extremely high with respect to power supplied by the utility grid, and there remain questions as to whether PV power can ever be competitive with electricity generated by fossil fuels. An objective approach to this important question was given in a previous paper by the authors which introduced analytical tools to define and project the technical/economic status of PV power from 1988 through the year 2010. In this paper, we apply these same tools to update the conclusions of our earlier study in the context of recent announcements by Amoco/Enron-Solar of projected sales of PV power at rates significantly less than the U.S. utility average.

  10. LEARNING CURVES OF LAPAROSCOPY – BARRIERS TO ADOPTION: A MNJIO EXPERIENCE!

    Directory of Open Access Journals (Sweden)

    Ramesh Maturi

    2016-06-01

    Full Text Available BACKGROUND Laparoscopy has been a new entry in the field of surgery with an active history of around just two decades. Today, it is in a position to challenge the conventional surgery which is in use since ages. It is making rapid inroads into various disciplines of surgery. Rapid improvements in optics, along with improvements in energy devices and mechanical stapling devices gave a fillip to acceptance of laparoscopy by the majority of surgeons. Also accumulating data and evidence has started influencing the sceptical, mobilising them to jump into the bandwagon. Barriers to adoption of new techniques, resistance to learning are common to human nature and it is necessary to have a systematic overview of the issues that might crop, so as to be prepared to overcome the problems of accepting laparoscopy into established centres of surgery. AIMS This publication is a reflection of our experience, our trials and tribulations in taking forward the laparoscopy program at our institution. This publication will give an overview of the steps involved in initiation of laparoscopy and aspires to be a source of answers, for day-to-day issues that crop during the process of learning laparoscopy. METHODS AND MATERIALS Just the way, executing laparoscopic surgery is a team effort, incorporating laparoscopy program in an institution is also a team effort where the members of team extend beyond the operating room. Involvement and co-operation of individuals across departments is a must along with benevolent seniors and a proactive administration. So we collated data by interviewing all the stakeholders of laparoscopy program, analysed observations of the faculty from the operating room and reviewed literature on the world wide web. Opinions of the administrators about their perceptions and the issues faced by the junior staff of the department were taken into consideration. Patients were interviewed before and after laparoscopic surgery. CONCLUSIONS Success at

  11. Robust Spatial Approximation of Laser Scanner Point Clouds by Means of Free-form Curve Approaches in Deformation Analysis

    Science.gov (United States)

    Bureick, Johannes; Alkhatib, Hamza; Neumann, Ingo

    2016-03-01

    In many geodetic engineering applications it is necessary to solve the problem of describing a measured data point cloud, measured, e. g. by laser scanner, by means of free-form curves or surfaces, e. g., with B-Splines as basis functions. The state of the art approaches to determine B-Splines yields results which are seriously manipulated by the occurrence of data gaps and outliers. Optimal and robust B-Spline fitting depend, however, on optimal selection of the knot vector. Hence we combine in our approach Monte-Carlo methods and the location and curvature of the measured data in order to determine the knot vector of the B-Spline in such a way that no oscillating effects at the edges of data gaps occur. We introduce an optimized approach based on computed weights by means of resampling techniques. In order to minimize the effect of outliers, we apply robust M-estimators for the estimation of control points. The above mentioned approach will be applied to a multi-sensor system based on kinematic terrestrial laserscanning in the field of rail track inspection.

  12. Simple approach to approximate predictions of the vapor–liquid equilibrium curve near the critical point and its application to Lennard-Jones fluids

    International Nuclear Information System (INIS)

    Staśkiewicz, B.; Okrasiński, W.

    2012-01-01

    We propose a simple analytical form of the vapor–liquid equilibrium curve near the critical point for Lennard-Jones fluids. Coexistence densities curves and vapor pressure have been determined using the Van der Waals and Dieterici equation of state. In described method the Bernoulli differential equations, critical exponent theory and some type of Maxwell's criterion have been used. Presented approach has not yet been used to determine analytical form of phase curves as done in this Letter. Lennard-Jones fluids have been considered for analysis. Comparison with experimental data is done. The accuracy of the method is described. -- Highlights: ► We propose a new analytical way to determine the VLE curve. ► Simple, mathematically straightforward form of phase curves is presented. ► Comparison with experimental data is discussed. ► The accuracy of the method has been confirmed.

  13. The influence of prior multiport experience on the learning curve for single-port thoracoscopic lobectomy: a multicentre comparative study†.

    Science.gov (United States)

    Martin-Ucar, Antonio E; Aragon, Javier; Bolufer Nadal, Sergio; Galvez Munoz, Carlos; Luo, Qigang; Perez Mendez, Itzel; Sihoe, Alan D L; Socci, Laura

    2017-06-01

    Competency in video-assisted thoracoscopic (VATS) lobectomy is estimated to be reached after the surgeon completes 50 cases. We wanted to explore the impact of competency in performing multiport VATS lobectomies on completing the needed number of single-port VATS. In a retrospective multicentre study, 6 individual surgeons (3 with previous competency in multiport VATS lobectomy and 3 without) submitted their first 50 cases of single-port VATS lobectomies. Extended and sublobar resections were excluded. Pre-, peri- and postoperative data were compared between the groups of surgeons. Chi-square and Wilcoxon's rank tests were used. The less experienced surgeons had previously attended dedicated training courses and visited with experts. A total of 300 cases were included [150 in Group A (surgeons with previous experience performing multiport VATS) and 150 in Group B (surgeons without extensive experience performing multiport VATS)]. Surgeons in Group B performed significantly more elective open lobectomies during their learning curve period than surgeons of Group A (58 vs 1). Patients in Group B were older and had more risk factors. There were 3 in-hospital deaths (respiratory failure, sepsis and fatal stroke). There were no differences between the groups in operative time, intensive care unit admissions, hospital stay, total complications, tumour size or number of N2 stations explored. Only the duration of intercostal drainage (2 vs 3 days, 0.012), incidence of respiratory tract infections (1% vs 7%, P  = 0.002) and conversion rates (4% vs 12%, P  = 0.018) were better in Group A. Patients characteristics played a role in the development of respiratory infections and longer drainage times but not in the need for conversion. Overall, postoperative outcomes during the learning curve period for single-port VATS lobectomies are not noticeably affected by previous multiport VATS experience. Less experienced surgeons were more selective in order to achieve

  14. Clinical experience with the first 40 cases with femtosecond laser cataract surgery technology: safety of the learning curve

    Directory of Open Access Journals (Sweden)

    Joao Crispim

    2015-10-01

    Full Text Available ABSTRACT Objective: To evaluate the introduction of the femtosecond laser (FSL to perform the key steps of the traditional cataract surgery process and the operational difficulties and safety of this new technology during routine use in an operating room in Brazil. Methods A retrospective study was conducted using the first cases operated on at a single center using the laser platform LenSx/Alcon with a soft contact lens patient interface.All patients underwent a detailed preoperative assessment.The anterior capsulotomy, nuclear fragmentation, and corneal incisions were created with the FSL; then, the surgery was completed following the standard phacoemulsification procedure. The main outcome measurements were difficulties and complications related to the learning curve and an analysis of postoperative uncorrected distance visual acuity (UDVA. Results: Of 31 patients (40 eyes, 9 patients had FSL cataract surgery in both eyes.The mean age was 64 ± 12 years (ranging from 42 to 82, the mean cataract nuclear sclerosis was grading 2 ± 0.6 (ranging from 1 to 4, and the preoperative mean UDVA in logMAR was 0.4 ± 0.2 (ranging from 0.1 to 1.3. Anterior capsulotomy was complete in all patients, and scissors were not needed to cut off any intact portion. The postoperative corneal incisions were not completely linear and showed some irregularities. Laser phaco-fragmentation was effective, with the division of the nucleus into smaller segments easily performed before phacoemulsification.After 1 month, the postoperative mean UDVA in logMAR was 0.1 ± 0.1 (ranging from 0.0 to 0.4 (P < 0.0001. Conclusion: With increasing surgical cases and experience, the phacoemulsification steps are performed precisely and effectively with FSL pretreatment, resulting in a safe learning curve.

  15. Recent trends in application of multivariate curve resolution approaches for improving gas chromatography-mass spectrometry analysis of essential oils.

    Science.gov (United States)

    Jalali-Heravi, Mehdi; Parastar, Hadi

    2011-08-15

    Essential oils (EOs) are valuable natural products that are popular nowadays in the world due to their effects on the health conditions of human beings and their role in preventing and curing diseases. In addition, EOs have a broad range of applications in foods, perfumes, cosmetics and human nutrition. Among different techniques for analysis of EOs, gas chromatography-mass spectrometry (GC-MS) is the most important one in recent years. However, there are some fundamental problems in GC-MS analysis including baseline drift, spectral background, noise, low S/N (signal to noise) ratio, changes in the peak shapes and co-elution. Multivariate curve resolution (MCR) approaches cope with ongoing challenges and are able to handle these problems. This review focuses on the application of MCR techniques for improving GC-MS analysis of EOs published between January 2000 and December 2010. In the first part, the importance of EOs in human life and their relevance in analytical chemistry is discussed. In the second part, an insight into some basics needed to understand prospects and limitations of the MCR techniques are given. In the third part, the significance of the combination of the MCR approaches with GC-MS analysis of EOs is highlighted. Furthermore, the commonly used algorithms for preprocessing, chemical rank determination, local rank analysis and multivariate resolution in the field of EOs analysis are reviewed. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. DEM Calibration Approach: design of experiment

    Science.gov (United States)

    Boikov, A. V.; Savelev, R. V.; Payor, V. A.

    2018-05-01

    The problem of DEM models calibration is considered in the article. It is proposed to divide models input parameters into those that require iterative calibration and those that are recommended to measure directly. A new method for model calibration based on the design of the experiment for iteratively calibrated parameters is proposed. The experiment is conducted using a specially designed stand. The results are processed with technical vision algorithms. Approximating functions are obtained and the error of the implemented software and hardware complex is estimated. The prospects of the obtained results are discussed.

  17. Behavioral approach to food waste: an experiment

    NARCIS (Netherlands)

    Jagau, H.; Vyrastekova, J.

    2017-01-01

    PURPOSE: The purpose of this paper is to explore the impact of behavioral interventions and nudging in dealing with the food waste problem. In particular, the authors implement an information campaign aiming to increase consumers’ awareness of the food waste problem. DESIGN/METHODOLOGY/APPROACH:

  18. Understanding the reductions in US corn ethanol production costs: an experience curve approach

    NARCIS (Netherlands)

    Hettinga, W.; Junginger, H.M.; Dekker, S.C.; Hoogwijk, M.; McAloon, A.; Hicks, K.

    2009-01-01

    The US is currently the world's largest ethanol producer. An increasing percentage is used as transportation fuel, but debates continue on its costs competitiveness and energy balance. In this study, technological development of ethanol production and resulting cost reductions are investigated by

  19. New method of safety assessment for pressure vessel of nuclear power plant--brief introduction of master curve approach

    International Nuclear Information System (INIS)

    Yang Wendou

    2011-01-01

    The new Master Curve Method is called as a revolutionary advance to the assessment of- reactor pressure vessel integrity in USA. This paper explains the origin, basis and standard of the Master Curve from the reactor pressure-temperature limit curve which assures the safety of nuclear power plant. According to the characteristics of brittle fracture which is greatly susceptible to the microstructure, the theory and the test method of the Master Curve as well as its statistical law which can be modeled using Weibull distribution are described in this paper. The meaning, advantage, application and importance of the Master Curve as well as the relation between the Master Curve and nuclear power safety are understood from the fitting formula for the fracture toughness database by Weibull distribution model. (author)

  20. Sensitivity analysis of the electrostatic force distance curve using Sobol’s method and design of experiments

    International Nuclear Information System (INIS)

    Alhossen, I; Bugarin, F; Segonds, S; Villeneuve-Faure, C; Baudoin, F

    2017-01-01

    Previous studies have demonstrated that the electrostatic force distance curve (EFDC) is a relevant way of probing injected charge in 3D. However, the EFDC needs a thorough investigation to be accurately analyzed and to provide information about charge localization. Interpreting the EFDC in terms of charge distribution is not straightforward from an experimental point of view. In this paper, a sensitivity analysis of the EFDC is studied using buried electrodes as a first approximation. In particular, the influence of input factors such as the electrode width, depth and applied potential are investigated. To reach this goal, the EFDC is fitted to a law described by four parameters, called logistic law, and the influence of the electrode parameters on the law parameters has been investigated. Then, two methods are applied—Sobol’s method and the factorial design of experiment—to quantify the effect of each factor on each parameter of the logistic law. Complementary results are obtained from both methods, demonstrating that the EFDC is not the result of the superposition of the contribution of each electrode parameter, but that it exhibits a strong contribution from electrode parameter interaction. Furthermore, thanks to these results, a matricial model has been developed to predict EFDCs for any combination of electrode characteristics. A good correlation is observed with the experiments, and this is promising for charge investigation using an EFDC. (paper)

  1. Sensitivity analysis of the electrostatic force distance curve using Sobol’s method and design of experiments

    Science.gov (United States)

    Alhossen, I.; Villeneuve-Faure, C.; Baudoin, F.; Bugarin, F.; Segonds, S.

    2017-01-01

    Previous studies have demonstrated that the electrostatic force distance curve (EFDC) is a relevant way of probing injected charge in 3D. However, the EFDC needs a thorough investigation to be accurately analyzed and to provide information about charge localization. Interpreting the EFDC in terms of charge distribution is not straightforward from an experimental point of view. In this paper, a sensitivity analysis of the EFDC is studied using buried electrodes as a first approximation. In particular, the influence of input factors such as the electrode width, depth and applied potential are investigated. To reach this goal, the EFDC is fitted to a law described by four parameters, called logistic law, and the influence of the electrode parameters on the law parameters has been investigated. Then, two methods are applied—Sobol’s method and the factorial design of experiment—to quantify the effect of each factor on each parameter of the logistic law. Complementary results are obtained from both methods, demonstrating that the EFDC is not the result of the superposition of the contribution of each electrode parameter, but that it exhibits a strong contribution from electrode parameter interaction. Furthermore, thanks to these results, a matricial model has been developed to predict EFDCs for any combination of electrode characteristics. A good correlation is observed with the experiments, and this is promising for charge investigation using an EFDC.

  2. Improving the reliability of POD curves in NDI methods using a Bayesian inversion approach for uncertainty quantification

    Science.gov (United States)

    Ben Abdessalem, A.; Jenson, F.; Calmon, P.

    2016-02-01

    This contribution provides an example of the possible advantages of adopting a Bayesian inversion approach to uncertainty quantification in nondestructive inspection methods. In such problem, the uncertainty associated to the random parameters is not always known and needs to be characterised from scattering signal measurements. The uncertainties may then correctly propagated in order to determine a reliable probability of detection curve. To this end, we establish a general Bayesian framework based on a non-parametric maximum likelihood function formulation and some priors from expert knowledge. However, the presented inverse problem is time-consuming and computationally intensive. To cope with this difficulty, we replace the real model by a surrogate one in order to speed-up the model evaluation and to make the problem to be computationally feasible for implementation. The least squares support vector regression is adopted as metamodelling technique due to its robustness to deal with non-linear problems. We illustrate the usefulness of this methodology through the control of tube with enclosed defect using ultrasonic inspection method.

  3. The Impacts of Technical Progress on Sulfur Dioxide Kuznets Curve in China: A Spatial Panel Data Approach

    Directory of Open Access Journals (Sweden)

    Zhimin Zhou

    2017-04-01

    Full Text Available This paper aims to reveal the nexus for sulfur dioxide (SO2 emission and income, as well as the effects of technical progress on SO2 emission in China based on environment Kuznets curve (EKC hypothesis. The spatial panel technique is used in case the coefficient estimates are biased due to the negligence of spatial dependence. With the provincial panel data of China from 2004 to 2014, this is the first research that finds an inverse N-trajectory of the relationship between SO2 emission and economic growth and confirms the beneficial impacts of technical advancement on SO2 emission abatement. The empirical results also suggest that the industrial structure change is an important driving force of the SO2 EKC. In addition, the direct and spillover effects of determinants on sulfur emission are clarified and estimated by a correct approach. Finally, we check the stability of our conclusions on the EKC shape for SO2 and technical progress effects when controlling for different variables and specifications, through which we find the turning points are sensitive to variables selections.

  4. An empirical examination of the Environmental Kuznets Curve hypothesis for carbon dioxide emissions in Ghana: an ARDL approach

    Directory of Open Access Journals (Sweden)

    Twerefou Daniel Kwabena

    2016-12-01

    Full Text Available The Environmental Kuznets Curve (EKC hypothesis postulates an inverted U-shaped relationship between different pollutants and economic growth. In Ghana, as in many other developing countries, there exist scanty studies that confirm or otherwise the EKC hypothesis with regards to CO2 emissions as well as the factors that drive CO2 emissions. This work aims to bridge this knowledge gap by addressing these two major questions using data from 1970 to 2010 and the Auto Regressive Distributed Lag (ARDL Bounds Testing approach. The results rather suggest a U-shaped relationship between per capita GDP and CO2 emissions per capita indicating the non-existence of the EKC hypothesis for CO2 in Ghana. This implies that further increase in per capita Gross Domestic Product (GDP will only be associated with increase in CO2 emissions as the income per capita turning point of about $624 at constant 2000 prices occurred between 1996 and 1997. Furthermore, our results reveal energy consumption and trade openness are positive long run drivers of CO2 emissions. It is therefore recommended that the enhancement of trade liberalization policies should ensure the use of cleaner technologies and products while investment in cleaner energy alternatives could help reduce CO2 emissions. We also recommend the implementation of the Low Carbon Development Strategy which integrates development and climate change mitigation actions.

  5. Endoscopic endonasal pituitary adenomas surgery: the surgical experience of 178 consecutive patients and learning curve of two neurosurgeons.

    Science.gov (United States)

    Shou, Xuefei; Shen, Ming; Zhang, Qilin; Zhang, Yichao; He, Wenqiang; Ma, Zengyi; Zhao, Yao; Li, Shiqi; Wang, Yongfei

    2016-11-30

    We aim to study surgical technique and analyze the related factors affecting tumor total removal and postoperative endocrinological remission for endoscopic endonasal pituitary adenomas surgery. We retrospectively analyzed 178 endoscopic endonasal pituitary adenomas surgery from March 2011 to May 2014. Endonasal approach included the routine transnasal-sphenoidal approach, transnasal- maxillary sinus approach in four cases and transnasal-clivus approach in one case. According to postoperative imaging data and endocrine examination results, total removal was achieved in 129 patients (72.5%), and endocrinological remission was achieved in 38 patients with functional adenomas (44.1%). Statistical analysis of the clinical data showed that total removal rate was much closely related to tumor volume (P = 0.006), and tumor invasiveness (P < 0.001). In this study, we found tumor sizes and invasion of cavernous sinus were related to total removal rate and endocrinological remission rate; the direction and degree of tumor invasion, and the surgeon's experience were the key influence factors of the endocrinological remission rate for invasive functional pituitary adenomas.

  6. Outage optimization - the US experience and approach

    International Nuclear Information System (INIS)

    LaPlatney, J.

    2007-01-01

    Sustainable development of Nuclear Energy depends heavily on excellent performance of the existing fleet which in turn depends heavily on the performance of planned outages. Some reactor fleets, for example Finland and Germany, have demonstrated sustained good outage performance from their start of commercial operation. Others, such as the US, have improved performance over time. The principles behind a successful outage optimization process are: -) duration is not sole measure of outage success, -) outage work must be performed safely, -) scope selection must focus on improving plant material condition to improve reliability, -) all approved outage work must be completed, -) work must be done cost effectively, -) post-outage plant reliability is a key measure of outage success, and -) outage lessons learned must be effectively implemented to achieve continuous improvement. This approach has proven its superiority over simple outage shortening, and has yielded good results in the US fleet over the past 15 years

  7. Laparoscopic adrenalectomy: Gaining experience by graded approach

    Directory of Open Access Journals (Sweden)

    Dalvi Abhay

    2006-01-01

    Full Text Available INTRODUCTION: Laparoscopic adrenalectomy (LA has become a gold standard in management of most of the adrenal disorders. Though report on the first laparoscopic adrenalectomy dates back to 1992, there is no series of LA reported from India. Starting Feb 2001, a graded approach to LA was undertaken in our center. Till March 2006, a total of 34 laparoscopic adrenalectomies were performed with success. MATERIALS AND METHODS: The endocrinology department primarily evaluated all patients. Patients were divided into Group A - unilateral LA and Group B - bilateral LA (BLA. The indications in Group A were pheochromocytoma (n=7, Conn′s syndrome (n=3, Cushing′s adenoma (n=2, incidentaloma (n=2; and in Group B, Cushing′s disease (CD following failed trans-sphenoid pituitary surgery (n = 8; ectopic ACTH- producing Cushing′s syndrome (n=1 and congenital adrenal hyperplasia (CAH (n=1. The lateral transabdominal route was used. RESULTS: The age group varied from 12-54 years, with mean age of 28.21 years. Average duration of surgery in Group A was 166.43 min (40-270 min and 190 min (150- 310 min in Group B. Average blood loss was 136.93 cc (20-400 cc in Group A and 92.5 cc (40-260 cc in Group B. There was one conversion in each group. Mean duration of surgical stay was 1.8 days (1-3 days in Group A and 2.6 days (2-4 days in Group B. All the patients in both groups were cured of their illness. Three patients in Group B developed Nelson′s syndrome. The mean follow up was of 24.16 months (4-61 months. CONCLUSION: LA though technically demanding, is feasible and safe. Graded approach to LA is the key to success.

  8. Two-year Outcomes from a Single Surgeon's Learning Curve Experience of Oblique Lateral Interbody Fusion without Intraoperative Neuromonitoring.

    Science.gov (United States)

    Woods, Kamal; Fonseca, Ahtziri; Miller, Larry E

    2017-12-22

    Introduction Oblique lumbar interbody fusion (OLIF) is a newer procedure that avoids the psoas and lumbosacral plexus due to its oblique trajectory into the retroperitoneal space. While early experience with OLIF is reassuring, the longer-term clinical efficacy has not been well established. The purpose of this study was to describe two-year clinical outcomes with OLIF performed by a single surgeon during the learning curve without the aid of the neuromonitoring. Materials and methods Chart review was performed for the consecutive patients who underwent OLIF by a single surgeon. Back pain severity on a visual analog scale (VAS) and Oswestry Disability Index (ODI) were collected preoperatively and postoperatively at six weeks, three months, six months, one year and two years. Results A total of 21 patients (38 levels) were included in this study. The indications for surgery were degenerative disc disease (n=10, 47.6%), spondylolisthesis (n=9, 42.9%) and spinal stenosis (n=6, 28.6%). The median operating room time was 351 minutes (interquartile range (IQR): 279-406 minutes), blood loss was 40 ml (IQR: 30-150 ml), and hospital stay was 2.0 days (IQR: 1.0-3.5 days). The complication rate was 9.5%, both venous injuries. There were no other perioperative complications. Back pain severity decreased by 70%, on average, over two years (p safe and clinically efficacious for up to two years. The complication rate in this cohort is similar to other published OLIF series and appears acceptable when compared to the lateral lumbar interbody fusion (LLIF) and the anterior lumbar interbody fusion (ALIF). No motor or sensory deficits were observed in this study, supporting the premise that the neuromonitoring is unnecessary in OLIF.

  9. The Impact of Student Teaching Experience on Pre-Service Teachers' Readiness for Technology Integration: A Mixed Methods Study with Growth Curve Modeling

    Science.gov (United States)

    Sun, Yan; Strobel, Johannes; Newby, Timothy J.

    2017-01-01

    Adopting a two-phase explanatory sequential mixed methods research design, the current study examined the impact of student teaching experiences on pre-service teachers' readiness for technology integration. In phase-1 of quantitative investigation, 2-level growth curve models were fitted using online repeated measures survey data collected from…

  10. What are the key drivers of MAC curves? A partial-equilibrium modelling approach for the UK

    International Nuclear Information System (INIS)

    Kesicki, Fabian

    2013-01-01

    Marginal abatement cost (MAC) curves are widely used for the assessment of costs related to CO 2 emissions reduction in environmental economics, as well as domestic and international climate policy. Several meta-analyses and model comparisons have previously been performed that aim to identify the causes for the wide range of MAC curves. Most of these concentrate on general equilibrium models with a focus on aspects such as specific model type and technology learning, while other important aspects remain almost unconsidered, including the availability of abatement technologies and level of discount rates. This paper addresses the influence of several key parameters on MAC curves for the United Kingdom and the year 2030. A technology-rich energy system model, UK MARKAL, is used to derive the MAC curves. The results of this study show that MAC curves are robust even to extreme fossil fuel price changes, while uncertainty around the choice of the discount rate, the availability of key abatement technologies and the demand level were singled out as the most important influencing factors. By using a different model type and studying a wider range of influencing factors, this paper contributes to the debate on the sensitivity of MAC curves. - Highlights: ► A partial-equilibrium model is employed to test key sensitivities of MAC curves. ► MAC curves are found to be robust to wide-ranging changes in fossil fuel prices. ► Most influencing factors are the discount rate, availability of key technologies. ► Further important uncertainty in MAC curves is related to demand changes

  11. Technology learning in a global - local perspective: - the interplay between technology diffusion, niche markets and experience curves

    International Nuclear Information System (INIS)

    Martinsen, Thomas

    2010-01-01

    Preventing dangerous global climate change requires timely deployment of nascent energy technologies with zero or low Co2 emissions. Managing the shift to a common sustainable technology path calls for insight about the influence of global technological change on the national energy system. Moreover, national policies are required to promote the shift to the new technology path. This calls for methods to analyse the national energy system within a global perspective. The objective of the work presented in this thesis was to investigate interplay between technology diffusion, niche markets and technology learning from the perspective of a small open economy like Norway. More specifically, develop methods to include the influence of technology learning manifested in experience and learning curves into national energy-economy-environment models. Moreover, apply the methods to investigate the potential influence and sensitivity to technology learning in a small open economy. In this thesis three such methods have been developed, applied and its importance assessed using Norway as an example. In this work three models have been linked. They are the global Energy Technology Perspectives model operated by the International Energy Agency, the Norwegian Markal model at the Institute for Energy Technology and the macro economic model MSG6 at Statistics Norway. Method one and two has been developed to manage the interplay between the models. In a local perspective technology learning in the global market is perceived as spillover. Based upon a review of the characteristics of technological change and learning curves and its application to energy system modelling some criteria important for the parameterization and modelling of spillover in a small open economy are suggested. The first method incorporates spillover into the national Markal model. The second method establishes a soft-link between the national models. The soft-link served two purposes; to provide input on demand

  12. Meta-analysis of single-arm survival studies: a distribution-free approach for estimating summary survival curves with random effects.

    Science.gov (United States)

    Combescure, Christophe; Foucher, Yohann; Jackson, Daniel

    2014-07-10

    In epidemiologic studies and clinical trials with time-dependent outcome (for instance death or disease progression), survival curves are used to describe the risk of the event over time. In meta-analyses of studies reporting a survival curve, the most informative finding is a summary survival curve. In this paper, we propose a method to obtain a distribution-free summary survival curve by expanding the product-limit estimator of survival for aggregated survival data. The extension of DerSimonian and Laird's methodology for multiple outcomes is applied to account for the between-study heterogeneity. Statistics I(2)  and H(2) are used to quantify the impact of the heterogeneity in the published survival curves. A statistical test for between-strata comparison is proposed, with the aim to explore study-level factors potentially associated with survival. The performance of the proposed approach is evaluated in a simulation study. Our approach is also applied to synthesize the survival of untreated patients with hepatocellular carcinoma from aggregate data of 27 studies and synthesize the graft survival of kidney transplant recipients from individual data from six hospitals. Copyright © 2014 John Wiley & Sons, Ltd.

  13. Stenting for curved lesions using a novel curved balloon: Preliminary experimental study.

    Science.gov (United States)

    Tomita, Hideshi; Higaki, Takashi; Kobayashi, Toshiki; Fujii, Takanari; Fujimoto, Kazuto

    2015-08-01

    Stenting may be a compelling approach to dilating curved lesions in congenital heart diseases. However, balloon-expandable stents, which are commonly used for congenital heart diseases, are usually deployed in a straight orientation. In this study, we evaluated the effect of stenting with a novel curved balloon considered to provide better conformability to the curved-angled lesion. In vitro experiments: A Palmaz Genesis(®) stent (Johnson & Johnson, Cordis Co, Bridgewater, NJ, USA) mounted on the Goku(®) curve (Tokai Medical Co. Nagoya, Japan) was dilated in vitro to observe directly the behavior of the stent and balloon assembly during expansion. Animal experiment: A short Express(®) Vascular SD (Boston Scientific Co, Marlborough, MA, USA) stent and a long Express(®) Vascular LD stent (Boston Scientific) mounted on the curved balloon were deployed in the curved vessel of a pig to observe the effect of stenting in vivo. In vitro experiments: Although the stent was dilated in a curved fashion, stent and balloon assembly also rotated conjointly during expansion of its curved portion. In the primary stenting of the short stent, the stent was dilated with rotation of the curved portion. The excised stent conformed to the curved vessel. As the long stent could not be negotiated across the mid-portion with the balloon in expansion when it started curving, the mid-portion of the stent failed to expand fully. Furthermore, the balloon, which became entangled with the stent strut, could not be retrieved even after complete deflation. This novel curved balloon catheter might be used for implantation of the short stent in a curved lesion; however, it should not be used for primary stenting of the long stent. Post-dilation to conform the stent to the angled vessel would be safer than primary stenting irrespective of stent length. Copyright © 2014 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  14. SPECIFICITIES OF COMPETENCY APPROACH IMPLEMENTATION: UKRAINIAN AND EUROPEAN EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Oksana V. Ovcharuk

    2010-08-01

    Full Text Available The article deals with the problems of competency approach implementation to the process of education content formation. The comparative analysis of European and Ukrainian experience of key competencies list discussion has done. Ukrainian perspectives of the competency approach integration to the content of education curricula are revealed.

  15. Estimate of the soil water retention curve from the sorptivity and β parameter calculated from an upward infiltration experiment

    Science.gov (United States)

    Moret-Fernández, D.; Latorre, B.

    2017-01-01

    The water retention curve (θ(h)), which defines the relationship between the volumetric water content (θ) and the matric potential (h), is of paramount importance to characterize the hydraulic behaviour of soils. Because current methods to estimate θ(h) are, in general, tedious and time consuming, alternative procedures to determine θ(h) are needed. Using an upward infiltration curve, the main objective of this work is to present a method to determine the parameters of the van Genuchten (1980) water retention curve (α and n) from the sorptivity (S) and the β parameter defined in the 1D infiltration equation proposed by Haverkamp et al. (1994). The first specific objective is to present an equation, based on the Haverkamp et al. (1994) analysis, which allows describing an upward infiltration process. Secondary, assuming a known saturated hydraulic conductivity, Ks, calculated on a finite soil column by the Darcy's law, a numerical procedure to calculate S and β by the inverse analysis of an exfiltration curve is presented. Finally, the α and n values are numerically calculated from Ks, S and β. To accomplish the first specific objective, cumulative upward infiltration curves simulated with HYDRUS-1D for sand, loam, silt and clay soils were compared to those calculated with the proposed equation, after applying the corresponding β and S calculated from the theoretical Ks, α and n. The same curves were used to: (i) study the influence of the exfiltration time on S and β estimations, (ii) evaluate the limits of the inverse analysis, and (iii) validate the feasibility of the method to estimate α and n. Next, the θ(h) parameters estimated with the numerical method on experimental soils were compared to those obtained with pressure cells. The results showed that the upward infiltration curve could be correctly described by the modified Haverkamp et al. (1994) equation. While S was only affected by early-time exfiltration data, the β parameter had a

  16. Comparison of polarisation curves and chronoamperometry experiments of titanium with and without ultrasonic vibrations of the electrolyte

    Directory of Open Access Journals (Sweden)

    Rebecca Leese

    2016-03-01

    Full Text Available Ultrasonic vibrations were applied to the electrolyte in polarisation curve and chronoamperometry to observe the effect of anodic dissolution with the aim to apply knowledge to electrochemical machining. The application of the ultrasonic vibrations to the electrolyte allowed the dissolution potential to be lowered considerably and the machining rates were increased.

  17. A regret theory approach to decision curve analysis: a novel method for eliciting decision makers' preferences and decision-making.

    Science.gov (United States)

    Tsalatsanis, Athanasios; Hozo, Iztok; Vickers, Andrew; Djulbegovic, Benjamin

    2010-09-16

    Decision curve analysis (DCA) has been proposed as an alternative method for evaluation of diagnostic tests, prediction models, and molecular markers. However, DCA is based on expected utility theory, which has been routinely violated by decision makers. Decision-making is governed by intuition (system 1), and analytical, deliberative process (system 2), thus, rational decision-making should reflect both formal principles of rationality and intuition about good decisions. We use the cognitive emotion of regret to serve as a link between systems 1 and 2 and to reformulate DCA. First, we analysed a classic decision tree describing three decision alternatives: treat, do not treat, and treat or no treat based on a predictive model. We then computed the expected regret for each of these alternatives as the difference between the utility of the action taken and the utility of the action that, in retrospect, should have been taken. For any pair of strategies, we measure the difference in net expected regret. Finally, we employ the concept of acceptable regret to identify the circumstances under which a potentially wrong strategy is tolerable to a decision-maker. We developed a novel dual visual analog scale to describe the relationship between regret associated with "omissions" (e.g. failure to treat) vs. "commissions" (e.g. treating unnecessary) and decision maker's preferences as expressed in terms of threshold probability. We then proved that the Net Expected Regret Difference, first presented in this paper, is equivalent to net benefits as described in the original DCA. Based on the concept of acceptable regret we identified the circumstances under which a decision maker tolerates a potentially wrong decision and expressed it in terms of probability of disease. We present a novel method for eliciting decision maker's preferences and an alternative derivation of DCA based on regret theory. Our approach may be intuitively more appealing to a decision-maker, particularly

  18. A regret theory approach to decision curve analysis: A novel method for eliciting decision makers' preferences and decision-making

    Directory of Open Access Journals (Sweden)

    Vickers Andrew

    2010-09-01

    Full Text Available Abstract Background Decision curve analysis (DCA has been proposed as an alternative method for evaluation of diagnostic tests, prediction models, and molecular markers. However, DCA is based on expected utility theory, which has been routinely violated by decision makers. Decision-making is governed by intuition (system 1, and analytical, deliberative process (system 2, thus, rational decision-making should reflect both formal principles of rationality and intuition about good decisions. We use the cognitive emotion of regret to serve as a link between systems 1 and 2 and to reformulate DCA. Methods First, we analysed a classic decision tree describing three decision alternatives: treat, do not treat, and treat or no treat based on a predictive model. We then computed the expected regret for each of these alternatives as the difference between the utility of the action taken and the utility of the action that, in retrospect, should have been taken. For any pair of strategies, we measure the difference in net expected regret. Finally, we employ the concept of acceptable regret to identify the circumstances under which a potentially wrong strategy is tolerable to a decision-maker. Results We developed a novel dual visual analog scale to describe the relationship between regret associated with "omissions" (e.g. failure to treat vs. "commissions" (e.g. treating unnecessary and decision maker's preferences as expressed in terms of threshold probability. We then proved that the Net Expected Regret Difference, first presented in this paper, is equivalent to net benefits as described in the original DCA. Based on the concept of acceptable regret we identified the circumstances under which a decision maker tolerates a potentially wrong decision and expressed it in terms of probability of disease. Conclusions We present a novel method for eliciting decision maker's preferences and an alternative derivation of DCA based on regret theory. Our approach may

  19. Adiabatic potential-energy curves of long-range Rydberg molecules: Two-electron R -matrix approach

    Czech Academy of Sciences Publication Activity Database

    Tarana, Michal; Čurík, Roman

    2016-01-01

    Roč. 93, č. 1 (2016), 012515 ISSN 0556-2791 R&D Projects: GA ČR(CZ) GP14-15989P Institutional support: RVO:61388955 Keywords : adiabatic-potential-energy curves * Rydberg molecules * theoretical chemistry Subject RIV: CF - Physical ; Theoretical Chemistry

  20. Adiabatic potential-energy curves of long-range Rydberg molecules: Two-electron R -matrix approach

    Czech Academy of Sciences Publication Activity Database

    Tarana, Michal; Čurík, Roman

    2016-01-01

    Roč. 93, č. 1 (2016), 012515 ISSN 0556-2791 R&D Projects: GA ČR(CZ) GP14-15989P Institutional support: RVO:61388955 Keywords : adiabatic-potential- energy curves * Rydberg molecules * theoretical chemistry Subject RIV: CF - Physical ; Theoretical Chemistry

  1. Estimation of surface water quality in a Yazoo River tributary using the duration curve and recurrence interval approach

    Science.gov (United States)

    Ying Ouyang; Prem B. Parajuli; Daniel A. Marion

    2013-01-01

    Pollution of surface water with harmful chemicals and eutrophication of rivers and lakes with excess nutrients are serious environmental concerns. This study estimated surface water quality in a stream within the Yazoo River Basin (YRB), Mississippi, USA, using the duration curve and recurrence interval analysis techniques. Data from the US Geological Survey (USGS)...

  2. Growth curves of preschool children in the northeast of iran: a population based study using quantile regression approach.

    Science.gov (United States)

    Payande, Abolfazl; Tabesh, Hamed; Shakeri, Mohammad Taghi; Saki, Azadeh; Safarian, Mohammad

    2013-01-14

    Growth charts are widely used to assess children's growth status and can provide a trajectory of growth during early important months of life. The objectives of this study are going to construct growth charts and normal values of weight-for-age for children aged 0 to 5 years using a powerful and applicable methodology. The results compare with the World Health Organization (WHO) references and semi-parametric LMS method of Cole and Green. A total of 70737 apparently healthy boys and girls aged 0 to 5 years were recruited in July 2004 for 20 days from those attending community clinics for routine health checks as a part of a national survey. Anthropometric measurements were done by trained health staff using WHO methodology. The nonparametric quantile regression method obtained by local constant kernel estimation of conditional quantiles curves using for estimation of curves and normal values. The weight-for-age growth curves for boys and girls aged from 0 to 5 years were derived utilizing a population of children living in the northeast of Iran. The results were similar to the ones obtained by the semi-parametric LMS method in the same data. Among all age groups from 0 to 5 years, the median values of children's weight living in the northeast of Iran were lower than the corresponding values in WHO reference data. The weight curves of boys were higher than those of girls in all age groups. The differences between growth patterns of children living in the northeast of Iran versus international ones necessitate using local and regional growth charts. International normal values may not properly recognize the populations at risk for growth problems in Iranian children. Quantile regression (QR) as a flexible method which doesn't require restricted assumptions, proposed for estimation reference curves and normal values.

  3. Computational experiment approach to advanced secondary mathematics curriculum

    CERN Document Server

    Abramovich, Sergei

    2014-01-01

    This book promotes the experimental mathematics approach in the context of secondary mathematics curriculum by exploring mathematical models depending on parameters that were typically considered advanced in the pre-digital education era. This approach, by drawing on the power of computers to perform numerical computations and graphical constructions, stimulates formal learning of mathematics through making sense of a computational experiment. It allows one (in the spirit of Freudenthal) to bridge serious mathematical content and contemporary teaching practice. In other words, the notion of teaching experiment can be extended to include a true mathematical experiment. When used appropriately, the approach creates conditions for collateral learning (in the spirit of Dewey) to occur including the development of skills important for engineering applications of mathematics. In the context of a mathematics teacher education program, this book addresses a call for the preparation of teachers capable of utilizing mo...

  4. Bootstrap confidence intervals for principal response curves

    NARCIS (Netherlands)

    Timmerman, Marieke E.; Ter Braak, Cajo J. F.

    2008-01-01

    The principal response curve (PRC) model is of use to analyse multivariate data resulting from experiments involving repeated sampling in time. The time-dependent treatment effects are represented by PRCs, which are functional in nature. The sample PRCs can be estimated using a raw approach, or the

  5. Bootstrap Confidence Intervals for Principal Response Curves

    NARCIS (Netherlands)

    Timmerman, M.E.; Braak, ter C.J.F.

    2008-01-01

    The principal response curve (PRC) model is of use to analyse multivariate data resulting from experiments involving repeated sampling in time. The time-dependent treatment effects are represented by PRCs, which are functional in nature. The sample PRCs can be estimated using a raw approach, or the

  6. Bootstrap rolling window estimation approach to analysis of the Environment Kuznets Curve hypothesis: evidence from the USA.

    Science.gov (United States)

    Aslan, Alper; Destek, Mehmet Akif; Okumus, Ilyas

    2018-01-01

    This study aims to examine the validity of inverted U-shaped Environmental Kuznets Curve by investigating the relationship between economic growth and environmental pollution for the period from 1966 to 2013 in the USA. Previous studies based on the assumption of parameter stability and obtained parameters do not change over the full sample. This study uses bootstrap rolling window estimation method to detect the possible changes in causal relations and also obtain the parameters for sub-sample periods. The results show that the parameter of economic growth has increasing trend in 1982-1996 sub-sample periods, and it has decreasing trend in 1996-2013 sub-sample periods. Therefore, the existence of inverted U-shaped Environmental Kuznets Curve is confirmed in the USA.

  7. A regret theory approach to decision curve analysis: A novel method for eliciting decision makers' preferences and decision-making

    OpenAIRE

    Vickers Andrew; Hozo Iztok; Tsalatsanis Athanasios; Djulbegovic Benjamin

    2010-01-01

    Abstract Background Decision curve analysis (DCA) has been proposed as an alternative method for evaluation of diagnostic tests, prediction models, and molecular markers. However, DCA is based on expected utility theory, which has been routinely violated by decision makers. Decision-making is governed by intuition (system 1), and analytical, deliberative process (system 2), thus, rational decision-making should reflect both formal principles of rationality and intuition about good decisions. ...

  8. Hot-blade cutting of EPS foam for double-curved surfaces—numerical simulation and experiments

    DEFF Research Database (Denmark)

    Petkov, Kiril P.; Hattel, Jesper Henri

    2017-01-01

    In the present paper, experimental and numerical studies of a newly developed process of Hot-Blade Cutting used for free forming of double-curved surfaces and cost effective rapid prototyping of expanded polystyrene foam is carried out. The experimental part of the study falls in two parts...... during the cutting process. A novel measurement method for determination of kerfwidth (i.e., the gap space after material removal) applying a commercially available large-scale optical 3D scanning technique was developed and used. A one-dimensional thermo-electro-mechanical numerical model for Hot...

  9. Earthquake experience suggests new approach to seismic criteria

    International Nuclear Information System (INIS)

    Knox, R.

    1983-01-01

    Progress in seismic qualification of nuclear power plants as reviewed at the 4th Pacific Basin Nuclear Conference in Vancouver, September 1983, is discussed. The lack of experience of earthquakes in existing nuclear plants can be compensated by the growing experience of actual earthquake effects in conventional power plants and similar installations. A survey of the effects on four power stations, with a total of twenty generating units, in the area strongly shaken by the San Fernando earthquake in California in 1971 is reported. The Canadian approach to seismic qualification, international criteria, Canadian/Korean experience, safety related equipment, the Tadotsu test facility and seismic tests are discussed. (U.K.)

  10. Comparative analysis of the apparent saturation hysteresis approach and the domain theory of hysteresis in respect of prediction of scanning curves and air entrapment

    Science.gov (United States)

    Beriozkin, A.; Mualem, Y.

    2018-05-01

    This study theoretically analyzes the concept of apparent saturation hysteresis, combined with the Scott et al. (1983) scaling approach, as suggested by Parker and Lenhard (1987), to account for the effect of air entrapment and release on the soil water hysteresis. We found that the theory of Parker and Lenhard (1987) is comprised of some mutually canceling mathematical operations, and when cleared of the superfluous intermediate calculations, their model reduces to the original Scott et al.'s (1983) scaling method, supplemented with the requirement of closure of scanning loops. Our analysis reveals that actually there is no effect of their technique of accounting for the entrapped air on the final prediction of the effective saturation (or water content) scanning curves. Our consideration indicates that the use of the Land (1968) formula for assessing the amount of entrapped air is in disaccord with the apparent saturation concept as introduced by Parker and Lenhard (1987). In this paper, a proper routine is suggested for predicting hysteretic scanning curves of any order, given the two measured main curves, in the complete hysteretic domain and some verification tests are carried out versus measured results. Accordingly, explicit closed-form formulae for direct prediction (with no need of intermediate calculation) of scanning curves up to the third order are derived to sustain our analysis.

  11. Subcriticality calculations for the FFTF reverse approach to critical experiment

    International Nuclear Information System (INIS)

    Selby, D.L.; Flanagan, G.F.

    1975-01-01

    The reverse approach to critical (RAC) experiments were performed in the ZPR-IX critical facility at Argonne National Laboratory. One of the major objectives of this project is to determine the adequacy of the low-level flux monitor (LLFM) detectors for initial loading of the Fast Flux Test Facility (FFTF). 5 references

  12. Workspace and sensorimotor theories : Complementary approaches to experience

    NARCIS (Netherlands)

    Degenaar, J.; Keijzer, F.

    A serious difficulty for theories of consciousness is to go beyond mere correlation between physical processes and experience. Currently, neural workspace and sensorimotor contingency theories are two of the most promising approaches to make any headway here. This paper explores the relation between

  13. Sustainability Reporting Experience by Universities: A Causal Configuration Approach

    Science.gov (United States)

    Zorio-Grima, Ana; Sierra-García, Laura; Garcia-Benau, Maria A.

    2018-01-01

    Purpose: The purpose of this research is to identify the combinations of factors leading to experience in sustainability reporting by Spanish public universities. Design/methodology/approach: Using a sample of 49 public universities in Spain, this paper identifies the combinations of factors on innovation profile, political and internal factors…

  14. Total hip arthroplasty by the direct anterior approach using a neck-preserving stem: Safety, efficacy and learning curve

    Directory of Open Access Journals (Sweden)

    Aditya Khemka

    2018-01-01

    Full Text Available Background: The concept of femoral neck preservation in total hip replacement (THR was introduced in 1993. It is postulated that retaining cortical bone of the femoral neck offers triplanar stability, uniform stress distribution, and accommodates physiological anteversion. However, data on safety, efficacy and learning curve are lacking. Materials and Methods: We prospectively assessed all patients who were operated for a THR with a short neck preserving stem (MiniHip between 2012 and 2014. The safety and learning curve were assessed by recording operative time; stem size; and adverse events including periprosthetic fracture; paresthesia; and limb length discrepancy (LLD. The cohort was divided into equal groups to assess the learning curve effect, and the cumulative sums (CUSUM test was performed to monitor intraoperative neck fractures. For assessment of efficacy, Oxford Hip Score (OHS and Short Form-36 (SF-36 scores were compared preoperatively and postoperatively. Results: 138 patients with median age 62 years (range 35–82 years were included with a median followup of 42 months (range 30–56 months. The minimum followup was 2.5 years. The OHS, SF-36 (physical and mental component scores improved by a mean score of 26, 28, and 27 points, respectively. All patients had LLD of <10 mm (1.9 mm ± 1.3. Adverse events included intraoperative neck fracture (n = 6, subsidence (n = 1, periprosthetic fracture (n = 1, paresthesia (n = 12, and trochanteric bursitis (n = 2. After early modification of the technique to use a smaller finishing broach, the CUSUM test demonstrated acceptable intraoperative neck fracture risk. The second surgery group had a reduced risk of intraoperative neck fracture (5/69 vs. 1/69 P = 0.2, reduced operative time (66 vs. 61 min, P = 0.06, and increased stem size (5 vs. 6, P = 0.09 although these differences were not statistically significant. Conclusions: The MiniHip stem is safe alternative to standard THR with good

  15. A Comparison of the Approaches to Customer Experience Analysis

    Directory of Open Access Journals (Sweden)

    Havíř David

    2017-08-01

    Full Text Available Nowadays, customer experience is receiving much attention in scientific and managerial community. Scholars and practitioners state that customer experience is the next area of competition. For a long time, there has been a call for a uniform, accurate definition, definition of its components, and the development of the customer experience frameworks. As this topic is new, there has been a considerable fragmentation. The question is if the fragmentation is still present and how can we address it. The aim of this paper is to summarize research on customer experience analysis and to explore and compare the dimensions describing customer experience listed in seven conceptual models with findings from 17 research projects on customer experience conducted after the year 2010. The purpose of this is to summarize recent knowledge, get the most comprehensive view on customer experience and its possible decomposition, and to reveal possible relationships between the dimensions. Based on a review of the available literature, the paper juxtaposes several approaches to customer experience analysis and compares their results to find similarities and differences among them. In the first step, the dimensions and factors of the customer experience were extracted from the seven models to analyze customer experience and they were compared with each other. This resulted in a set of dimensions and factors. In the next step, customer experience factors and dimensions were extracted from 17 practical research papers on customer experience. Finally, based on their descriptions and found similarities, the dimensions and factors were put together into several groups, as this grouping and creation of the new universal set of dimensions might solve the fragmentation issue.

  16. Sensitivity equation for quantitative analysis with multivariate curve resolution-alternating least-squares: theoretical and experimental approach.

    Science.gov (United States)

    Bauza, María C; Ibañez, Gabriela A; Tauler, Romà; Olivieri, Alejandro C

    2012-10-16

    A new equation is derived for estimating the sensitivity when the multivariate curve resolution-alternating least-squares (MCR-ALS) method is applied to second-order multivariate calibration data. The validity of the expression is substantiated by extensive Monte Carlo noise addition simulations. The multivariate selectivity can be derived from the new sensitivity expression. Other important figures of merit, such as limit of detection, limit of quantitation, and concentration uncertainty of MCR-ALS quantitative estimations can be easily estimated from the proposed sensitivity expression and the instrumental noise. An experimental example involving the determination of an analyte in the presence of uncalibrated interfering agents is described in detail, involving second-order time-decaying sensitized lanthanide luminescence excitation spectra. The estimated figures of merit are reasonably correlated with the analytical features of the analyzed experimental system.

  17. Living with a systematic approach to training. A personal experience

    International Nuclear Information System (INIS)

    Duarte, R.F.

    2002-01-01

    The Systematic Approach to Training (SAT) plays an important role in the safe operation of a nuclear power plant. It can often be seen as the answer to all training needs but it can sometimes fall victim to its own rigidity and inertia. This paper outlines the personal experiences and conceptual models of a former Human Resources Manager with responsibility for both pre operational and operational training. (author)

  18. Prediction and validation of burnout curves for Goettelborn char using reaction kinetics determined in shock tube experiments

    Energy Technology Data Exchange (ETDEWEB)

    Moors, J.H.J.; Banin, V.E.; Haas, J.H.P.; Weber, R.; Veefkind, A. [Eindhoven University of Technology, Eindhoven (Netherlands). Dept. of Applied Physics

    1999-01-01

    Using a shock tube facility the combustion characteristics of pulverised char ({lt} 10 {mu}m) were measured. A prediction was made for the burnout behaviour of a commercial sized char particle (75-90 {mu}m) in different ambient conditions using a `pseudo kinetic` approach. In this approach the kinetic rate of a surface containing micro pores is determined and these `pseudo kinetics` are then applied to the larger particle not taking into account the micro pores. Comparison of the predictions with measurements done with an isothermal plug flow reactor showed this approach to be valid within experimental error for low burnout. A linear decrease of the kinetic reaction rate with burnout is shown to predict the burnout behaviour in the complete range of burnout. A possible explanation for this linear decrease could be a growing fraction of non-combustible material in the char particles during burnout. 11 refs., 6 figs., 2 tabs.

  19. Experience in Design and Learning Approaches – Enhancing the Framework for Experience

    Directory of Open Access Journals (Sweden)

    Merja L.M. Bauters

    2017-06-01

    Full Text Available In design and learning studies, an increasing amount of attention has been paid to experience. Many design approaches relate experience to embodiment and phenomenology. The growth in the number of applications that use the Internet of Things (IoT has shifted human interactions from mobile devices and computers to tangible, material things. In education, the pressure to learn and update skills and knowledge, especially in work environments, has underlined the challenge of understanding how workers learn from reflection while working. These directions have been fuelled by research findings in the neurosciences, embodied cognition, the extended phenomenological–cognitive system and the role of emotions in decision-making and meaning making. The perspective on experience in different disciplines varies, and the aim is often to categorise experience. These approaches provide a worthwhile view of the importance of experience in learning and design, such as the recent emphasis on conceptual and epistemological knowledge creation. In pragmatism, experience plays a considerable role in research, art, communication and reflection. Therefore, I rely on Peirce’s communicative theory of signs and Dewey’s philosophy of experience to examine how experience is connected to reflection and therefore how it is necessarily tangible.

  20. ROBUST DECLINE CURVE ANALYSIS

    Directory of Open Access Journals (Sweden)

    Sutawanir Darwis

    2012-05-01

    Full Text Available Empirical decline curve analysis of oil production data gives reasonable answer in hyperbolic type curves situations; however the methodology has limitations in fitting real historical production data in present of unusual observations due to the effect of the treatment to the well in order to increase production capacity. The development ofrobust least squares offers new possibilities in better fitting production data using declinecurve analysis by down weighting the unusual observations. This paper proposes a robustleast squares fitting lmRobMM approach to estimate the decline rate of daily production data and compares the results with reservoir simulation results. For case study, we usethe oil production data at TBA Field West Java. The results demonstrated that theapproach is suitable for decline curve fitting and offers a new insight in decline curve analysis in the present of unusual observations.

  1. Experience in Design and Learning Approaches – Enhancing the Framework for Experience

    OpenAIRE

    Merja L.M. Bauters

    2017-01-01

    In design and learning studies, an increasing amount of attention has been paid to experience. Many design approaches relate experience to embodiment and phenomenology. The growth in the number of applications that use the Internet of Things (IoT) has shifted human interactions from mobile devices and computers to tangible, material things. In education, the pressure to learn and update skills and knowledge, especially in work environments, has underlined the challenge of understanding how wo...

  2. Object Oriented Approach to Software Development for LHC Experiments

    CERN Multimedia

    Tummers, B J; Day, C; Innocente, V; Mount, R; Visser, E; Burnett, T H; Balke, C

    2002-01-01

    % RD41 \\\\ \\\\ We propose to study the viability of the Object Oriented~(OO) approach for developing the code for LHC experiments. The authors of this proposal will learn the key issues of this approach:~~OO analysis and design. Several methodologies will be studied to select the most appropriate for the High Energy Physics case. Some Computer Aided Software Engineering tools and implementation languages will be evaluated. These studies will be carried out with various well-defined prototypes, some of which have been defined in a preceding study and some of which will be defined in the course of this R\\&D project. We propose to also study in this project how the OO approach enhances a different, and hopefully better, project management. Management tools will be tried and professional training will be organized.

  3. Overcoming the learning curve of single-port total laparoscopic hysterectomy with barbed suture: a single surgeon's initial experience.

    Science.gov (United States)

    Lee, Yoon Hee; Chong, Gun Oh; Kim, Mi Ju; Gy Hong, Dae; Lee, Yoon Soon

    2017-09-01

    Single-port total laparoscopic hysterectomy (TLH) has not been widely used because of its technical difficulty and steep learning curve, especially the laparoscopic suturing of the vaginal stump. Barbed suturing is a new technology that has the potential to greatly facilitate laparoscopic suturing. To compare surgical outcomes and vaginal vault healing between barbed sutures and traditional sutures in the repair of the vaginal vault during single-port TLH. Between August 2013 and June 2015, we performed single-port TLH in 85 consecutive patients for benign or premalignant gynecological conditions. The first 48 patients underwent single-port TLH with traditional interrupted sutures, and the next 37 patients underwent single-port TLH with absorbable unidirectional knotless barbed sutures for repair of the vaginal vault. The patient characteristics (age, body mass index), procedures performed, uterine weight, and uterine disease were similar between the groups. There were no differences in blood loss, hemoglobin change, length of hospital stay, or perioperative complications. Operative time and the time required for vaginal cuff suturing were significantly shorter in the barbed suture group than in the traditional suture group (57.8 ±13.5 vs. 80.1 ±18.7 min, p < 0.001; 5.5 ±1.7 vs. 12.9 ±3.5 min, p < 0.001). Moreover, the use of barbed sutures significantly reduced the incidence of vaginal granulation tissue formation (2.7% vs. 35.4%, p < 0.001). Use of barbed sutures in single-port TLH reduced the operative time, suturing time of the vaginal vault, and formation of vaginal granulation tissue. Barbed suturing may help overcome surgical difficulties and vaginal cuff complications.

  4. Environmental Kuznets curves-real progress or passing the buck? A case for consumption-based approaches

    International Nuclear Information System (INIS)

    Rothman, Dale S.

    1998-01-01

    Recent research has examined the hypothesis of an environmental Kuznets curve (EKC): the notion that environmental impact increases in the early stages of development followed by declines in the later stages. These studies have focused on the relationship between per capita income and a variety of environmental indicators. Results imply that EKCs may exist for a number of cases. However, the measures of environmental impact used generally focus on production processes and reflect environmental impacts that are local in nature and for which abatement is relatively inexpensive in terms of monetary costs and/or lifestyle changes. Significantly, more consumption-based measures, such as CO 2 emissions and municipal waste, for which impacts are relatively easy to externalize or costly to control, show no tendency to decline with increasing per capita income. By considering consumption and trade patterns, the author re-examines the concept of the EKC and propose the use of alternative, consumption-based measures of environmental impact. The author speculates that what appear to be improvements in environmental quality may in reality be indicators of increased ability of consumers in wealthy nations to distance themselves from the environmental degradation associated with their consumption

  5. Is there an Environmental Kuznets Curve for South Africa? A co-summability approach using a century of data

    International Nuclear Information System (INIS)

    Ben Nasr, Adnen; Gupta, Rangan; Sato, João Ricardo

    2015-01-01

    There exists a huge international literature on the, so-called, Environmental Kuznets Curve (EKC) hypothesis, which in turn, postulates an inverted u-shaped relationship between environmental pollutants and output. The empirical literature on EKC has mainly used test for cointegration, based on polynomial relationships between pollution and income. Motivated by the fact that, measured in per capita CO 2 equivalent emissions, South Africa is the world's most carbon-intensive non-oil-producing developing country, this paper aims to test the validity of the EKC for South Africa. For this purpose, we use a century of data (1911–2010), to capture the process of development better compared to short sample-based research; and the concept of co-summability, which is designed to analyze non-linear long-run relations among persistent processes. Our results, however, provide no support of the EKC for South Africa, both for the full-sample and sub-samples (determined by tests of structural breaks), implying that to reduce emissions without sacrificing growth, policies should be aimed at promoting energy efficiency. - Highlights: • The co-summability concept is used to test the validity of the EKC for South Africa. • The case of structural breaks is also considered when testing for the EKC. • Results provide no support of the EKC for South Africa. • To reduce CO2 emissions without sacrificing growth, policies should be aimed at promoting energy efficiency.

  6. An industrial approach to design compelling VR and AR experience

    Science.gov (United States)

    Richir, Simon; Fuchs, Philippe; Lourdeaux, Domitile; Buche, Cédric; Querrec, Ronan

    2013-03-01

    The convergence of technologies currently observed in the field of VR, AR, robotics and consumer electronic reinforces the trend of new applications appearing every day. But when transferring knowledge acquired from research to businesses, research laboratories are often at a loss because of a lack of knowledge of the design and integration processes in creating an industrial scale product. In fact, the innovation approaches that take a good idea from the laboratory to a successful industrial product are often little known to researchers. The objective of this paper is to present the results of the work of several research teams that have finalized a working method for researchers and manufacturers that allow them to design virtual or augmented reality systems and enable their users to enjoy "a compelling VR experience". That approach, called "the I2I method", present 11 phases from "Establishing technological and competitive intelligence and industrial property" to "Improvements" through the "Definition of the Behavioral Interface, Virtual Environment and Behavioral Software Assistance". As a result of the experience gained by various research teams, this design approach benefits from contributions from current VR and AR research. Our objective is to validate and continuously move such multidisciplinary design team methods forward.

  7. A viral metagenomic approach on a nonmetagenomic experiment

    DEFF Research Database (Denmark)

    Bovo, Samuele; Mazzoni, Gianluca; Ribani, Anisa

    2017-01-01

    Shot-gun next generation sequencing (NGS) on whole DNA extracted from specimens collected from mammals often produces reads that are not mapped (i.e. unmapped reads) on the host reference genome and that are usually discarded as by-products of the experiments. In this study, we mined Ion Torrent...... reads obtained by sequencing DNA isolated from archived blood samples collected from 100 performance tested Italian Large White pigs. Two reduced representation libraries were prepared from two DNA pools constructed each from 50 equimolar DNA samples. Bioinformatic analyses were carried out to mine...... unmapped reads on the reference pig genome that were obtained from the two NGS datasets. In silico analyses included read mapping and sequence assembly approaches for a viral metagenomic analysis using the NCBI Viral Genome Resource. Our approach identified sequences matching several viruses...

  8. Climatic and basin factors affecting the flood frequency curve: PART I – A simple sensitivity analysis based on the continuous simulation approach

    Directory of Open Access Journals (Sweden)

    A. M. Hashemi

    2000-01-01

    Full Text Available Regionalized and at-site flood frequency curves exhibit considerable variability in their shapes, but the factors controlling the variability (other than sampling effects are not well understood. An application of the Monte Carlo simulation-based derived distribution approach is presented in this two-part paper to explore the influence of climate, described by simulated rainfall and evapotranspiration time series, and basin factors on the flood frequency curve (ffc. The sensitivity analysis conducted in the paper should not be interpreted as reflecting possible climate changes, but the results can provide an indication of the changes to which the flood frequency curve might be sensitive. A single site Neyman Scott point process model of rainfall, with convective and stratiform cells (Cowpertwait, 1994; 1995, has been employed to generate synthetic rainfall inputs to a rainfall runoff model. The time series of the potential evapotranspiration (ETp demand has been represented through an AR(n model with seasonal component, while a simplified version of the ARNO rainfall-runoff model (Todini, 1996 has been employed to simulate the continuous discharge time series. All these models have been parameterised in a realistic manner using observed data and results from previous applications, to obtain ‘reference’ parameter sets for a synthetic case study. Subsequently, perturbations to the model parameters have been made one-at-a-time and the sensitivities of the generated annual maximum rainfall and flood frequency curves (unstandardised, and standardised by the mean have been assessed. Overall, the sensitivity analysis described in this paper suggests that the soil moisture regime, and, in particular, the probability distribution of soil moisture content at the storm arrival time, can be considered as a unifying link between the perturbations to the several parameters and their effects on the standardised and unstandardised ffcs, thus revealing the

  9. Initial experience with intravenous pentobarbital sedation for children undergoing MRI at a tertiary care pediatric hospital: the learning curve

    International Nuclear Information System (INIS)

    Greenberg, S.B.; Adams, R.C.; Aspinall, C.L.

    2000-01-01

    Objective. Our purpose is to describe the initial experience with intravenous pentobarbital sedation in children undergoing MRI at a tertiary pediatric hospital to identify errors associated with inexperience. Subjects and methods. The study included the first 100 children sedated with intravenous pentobarbital prior to magnetic resonance examination at a tertiary pediatric hospital. The protocol included a maximum dose of 6 mg/kg administered in three divided doses with the total dose not to exceed 200 mg. Flow sheets documenting vital signs, administered drug doses, and adverse reactions were maintained contemporaneous to sedation. Results. Sedation was successful in 92 children. Of the eight children who failed sedation, three were at least 12 years old and three weighed more than 50 kg. χ 2 tests identified significantly greater failure rates in children older than 11 years or weight greater than 50 kg. Two children had prolonged sedation after the maximum suggested dose was exceeded. Conclusions. The success rate was good, but could have been improved by restricting the use of pentobarbital to children less than 12 years of age and weighing less than 50 kg. Radiologists inexperienced with intravenous sedation should strictly observe the maximum suggested dose of pentobarbital to prevent prolonged sedation. (orig.)

  10. Perioperative surgical complications and learning curve associated with minimally invasive transforaminal lumbar interbody fusion: a single-institute experience.

    Science.gov (United States)

    Park, Yung; Lee, Soo Bin; Seok, Sang Ok; Jo, Byung Woo; Ha, Joong Won

    2015-03-01

    As surgical complications tend to occur more frequently in the beginning stages of a surgeon's career, knowledge of perioperative complications is important to perform a safe procedure, especially if the surgeon is a novice. We sought to identify and describe perioperative complications and their management in connection with minimally invasive transforaminal lumbar interbody fusion (TLIF). We performed a retrospective chart review of our first 124 patients who underwent minimally invasive TLIF. The primary outcome measure was adverse events during the perioperative period, including neurovascular injury, implant-related complications, and wound infection. Pseudarthroses and adjacent segment pathologies were not included in this review. Adverse events that were not specifically related to spinal surgery and did not affect recovery were also excluded. Perioperative complications occurred in 9% of patients (11/124); including three cases of temporary postoperative neuralgia, two deep wound infections, two pedicle screw misplacements, two cage migrations, one dural tear, and one grafted bone extrusion. No neurologic deficits were reported. Eight complications occurred in the first one-third of the series and only 3 complications occurred in the last two-thirds of the series. Additional surgeries were performed in 6% of patients (7/124); including four reoperations (two for cage migrations, one for a misplaced screw, and one for an extruded graft bone fragment) and three hardware removals (one for a misplaced screw and two for infected cages). We found perioperative complications occurred more often in the early period of a surgeon's experience with minimally invasive TLIF. Implant-related complications were common and successfully managed by additional surgeries in this series. We suggest greater caution should be exercised to avoid the potential complications, especially when surgeon is a novice to this procedure.

  11. Ethnobotanical approaches of traditional medicine studies: some experiences from Asia.

    Science.gov (United States)

    Sheng-Ji, P

    2001-01-01

    Ethnobotany, as a research field of science, has been widely used for the documentation of indigenous knowledge on the use of plants and for providing an inventory of useful plants from local flora in Asian countries. Plants that are used for traditional herbal medicine in different countries are an important part of these studies. However, in some countries in recent years, ethnobotanical studies have been used for the discovery of new drugs and new drug development. In general, experiences gained from ethnobotanical approaches of traditional medicinal studies in China and Himalayan countries have helped drug production and new drug development. At the same time, in many cases, over-harvesting, degradation of medical plants, and loss of traditional medical knowledge in local communities are common problems in these resource areas. Issues of indigenous knowledge, intellectual property rights, and uncontrolled transboundary trade in medicinal plants occur frequently in the region. This paper discusses ethnobotanical approaches of traditional medicinal studies, in reference to experiences from China and Himalayan countries, with an emphasis on the conservation of traditional medical knowledge and medical plant resources.

  12. Calculation approaches for grid usage fees to influence the load curve in the distribution grid level; Berechnungsansaetze fuer Netznutzungsentgelte zur Beeinflussung des Lastverlaufs in der Verteilernetzebene

    Energy Technology Data Exchange (ETDEWEB)

    Illing, Bjoern

    2014-09-08

    Dominated by the energy policy the decentralized German energy market is changing. One mature target of the government is to increase the contribution of renewable generation to the gross electricity consumption. In order to achieve this target disadvantages like an increased need for capacity management occurs. Load reduction and variable grid fees offer the grid operator solutions to realize capacity management by influencing the load profile. The evolution of the current grid fees towards more causality is required to adapt these approaches. Two calculation approaches are developed in this assignment. On the one hand multivariable grid fees keeping the current components demand and energy charge. Additional to the grid costs grid load dependent parameters like the amount of decentralized feed-ins, time and local circumstances as well as grid capacities are considered. On the other hand the grid fee flat-rate which represents a demand based model on a monthly level. Both approaches are designed to meet the criteria for future grid fees. By means of a case study the effects of the grid fees on the load profile at the low voltage grid is simulated. Thereby the consumption is represented by different behaviour models and the results are scaled at the benchmark grid area. The resulting load curve is analyzed concerning the effects of peak load reduction as well as the integration of renewable energy sources. Additionally the combined effect of grid fees and electricity tariffs is evaluated. Finally the work discusses the launching of grid fees in the tense atmosphere of politics, legislation and grid operation. Results of this work are two calculation approaches designed for grid operators to define the grid fees. Multivariable grid fees are based on the current calculation scheme. Hereby demand and energy charges are weighted by time, locational and load related dependencies. The grid fee flat-rate defines a limitation in demand extraction. Different demand levels

  13. Novel isotopic N, N-Dimethyl Leucine (iDiLeu) Reagents Enable Absolute Quantification of Peptides and Proteins Using a Standard Curve Approach

    Science.gov (United States)

    Greer, Tyler; Lietz, Christopher B.; Xiang, Feng; Li, Lingjun

    2015-01-01

    Absolute quantification of protein targets using liquid chromatography-mass spectrometry (LC-MS) is a key component of candidate biomarker validation. One popular method combines multiple reaction monitoring (MRM) using a triple quadrupole instrument with stable isotope-labeled standards (SIS) for absolute quantification (AQUA). LC-MRM AQUA assays are sensitive and specific, but they are also expensive because of the cost of synthesizing stable isotope peptide standards. While the chemical modification approach using mass differential tags for relative and absolute quantification (mTRAQ) represents a more economical approach when quantifying large numbers of peptides, these reagents are costly and still suffer from lower throughput because only two concentration values per peptide can be obtained in a single LC-MS run. Here, we have developed and applied a set of five novel mass difference reagents, isotopic N, N-dimethyl leucine (iDiLeu). These labels contain an amine reactive group, triazine ester, are cost effective because of their synthetic simplicity, and have increased throughput compared with previous LC-MS quantification methods by allowing construction of a four-point standard curve in one run. iDiLeu-labeled peptides show remarkably similar retention time shifts, slightly lower energy thresholds for higher-energy collisional dissociation (HCD) fragmentation, and high quantification accuracy for trypsin-digested protein samples (median errors <15%). By spiking in an iDiLeu-labeled neuropeptide, allatostatin, into mouse urine matrix, two quantification methods are validated. The first uses one labeled peptide as an internal standard to normalize labeled peptide peak areas across runs (<19% error), whereas the second enables standard curve creation and analyte quantification in one run (<8% error).

  14. A study of pH-dependent photodegradation of amiloride by a multivariate curve resolution approach to combined kinetic and acid-base titration UV data.

    Science.gov (United States)

    De Luca, Michele; Ioele, Giuseppina; Mas, Sílvia; Tauler, Romà; Ragno, Gaetano

    2012-11-21

    Amiloride photostability at different pH values was studied in depth by applying Multivariate Curve Resolution Alternating Least Squares (MCR-ALS) to the UV spectrophotometric data from drug solutions exposed to stressing irradiation. Resolution of all degradation photoproducts was possible by simultaneous spectrophotometric analysis of kinetic photodegradation and acid-base titration experiments. Amiloride photodegradation showed to be strongly dependent on pH. Two hard modelling constraints were sequentially used in MCR-ALS for the unambiguous resolution of all the species involved in the photodegradation process. An amiloride acid-base system was defined by using the equilibrium constraint, and the photodegradation pathway was modelled taking into account the kinetic constraint. The simultaneous analysis of photodegradation and titration experiments revealed the presence of eight different species, which were differently distributed according to pH and time. Concentration profiles of all the species as well as their pure spectra were resolved and kinetic rate constants were estimated. The values of rate constants changed with pH and under alkaline conditions the degradation pathway and photoproducts also changed. These results were compared to those obtained by LC-MS analysis from drug photodegradation experiments. MS analysis allowed the identification of up to five species and showed the simultaneous presence of more than one acid-base equilibrium.

  15. COMPLICATIONS OF ENDONASAL ENDOSCOPIC TRANSSPHENOIDAL APPROACH FOR PITUITARY ADENOMAS: OUR EXPERIENCE IN 50 PATIENTS TREATED AT OUR TERTIARY CENTRE

    Directory of Open Access Journals (Sweden)

    Mani Ram

    2015-12-01

    Full Text Available INTRODUCTION Between September 2013 and October 2014, we conducted a retrospective analysis to assess the complications related to endoscopic pituitary surgery in a series of 50 patients. We analysed the complications in preoperative, postoperative and endocrinological categories. We had a follow up of 1-2 years. Endonasal endoscopic transsphenoidal surgery (ETSS is an effective option for pituitary tumors. Complications do occur, but they can be reduced with experience & expertise and there is a steep learning curve. It demands a multidisciplinary approach.

  16. METHODICAL APPROACHES TO THE CREATION MOOC (EXPERIENCE LAC

    Directory of Open Access Journals (Sweden)

    Larysa Nozdrina

    2016-03-01

    Full Text Available The article presents a number of problems, determining the current state of development of the domestic market of massive open online courses (MOOC. Considering the aim of the research, there is described national experience in this area, proposed and substantiated a number of the criteria and methodological approaches to the implementation of MOOC in higher education. The development of MOOC in the Lviv Academy of Commerce (LAC is reviewed as example. The main factors which determine the success of this educational innovation in the domestic market and are put under the research are software platforms, multimedia software for creating video lectures, course structure and support the learning process. The results of study which have been analyzed in this course can have a positive impact on the functioning of the market MOOC in Ukrainian universities. The article focuses on finding the ways of improving the process of developing and implementing MOOC in higher education in the example of LAC where Web-center on the MOODLE platform is used for e-learning. Further research should focus on the development of institutional mechanisms to ensure the effective design, implementation and operation of the MOOC in the universities in Ukraine. Particular attention during learning in massive open online course should be aimed at improving the educational process and to strengthen student's motivation in MOOC. Experience of MOOC's development in LAC can be useful at creating similar courses at other institutions of higher education in the different platforms, both MOODLE, and on the others

  17. Modeling Studies of Inhomogeneity Effects during Laser Flash Photolysis Experiments: A Reaction-Diffusion Approach.

    Science.gov (United States)

    Dóka, Éva; Lente, Gábor

    2017-04-13

    This work presents a rigorous mathematical study of the effect of unavoidable inhomogeneities in laser flash photolysis experiments. There are two different kinds of inhomegenities: the first arises from diffusion, whereas the second one has geometric origins (the shapes of the excitation and detection light beams). Both of these are taken into account in our reported model, which gives rise to a set of reaction-diffusion type partial differential equations. These equations are solved by a specially developed finite volume method. As an example, the aqueous reaction between the sulfate ion radical and iodide ion is used, for which sufficiently detailed experimental data are available from an earlier publication. The results showed that diffusion itself is in general too slow to influence the kinetic curves on the usual time scales of laser flash photolysis experiments. However, the use of the absorbances measured (e.g., to calculate the molar absorption coefficients of transient species) requires very detailed mathematical consideration and full knowledge of the geometrical shapes of the excitation laser beam and the separate detection light beam. It is also noted that the usual pseudo-first-order approach to evaluating the kinetic traces can be used successfully even if the usual large excess condition is not rigorously met in the reaction cell locally.

  18. Estimating Corporate Yield Curves

    OpenAIRE

    Antionio Diaz; Frank Skinner

    2001-01-01

    This paper represents the first study of retail deposit spreads of UK financial institutions using stochastic interest rate modelling and the market comparable approach. By replicating quoted fixed deposit rates using the Black Derman and Toy (1990) stochastic interest rate model, we find that the spread between fixed and variable rates of interest can be modeled (and priced) using an interest rate swap analogy. We also find that we can estimate an individual bank deposit yield curve as a spr...

  19. Fundamental-mode sources in approach to critical experiments

    International Nuclear Information System (INIS)

    Goda, J.; Busch, R.

    2000-01-01

    An equivalent fundamental-mode source is an imaginary source that is distributed identically in space, energy, and angle to the fundamental-mode fission source. Therefore, it produces the same neutron multiplication as the fundamental-mode fission source. Even if two source distributions produce the same number of spontaneous fission neutrons, they will not necessarily contribute equally toward the multiplication of a given system. A method of comparing the relative importance of source distributions is needed. A factor, denoted as g* and defined as the ratio of the fixed-source multiplication to the fundamental-mode multiplication, is used to convert a given source strength to its equivalent fundamental-mode source strength. This factor is of interest to criticality safety as it relates to the 1/M method of approach to critical. Ideally, a plot of 1/M versus κ eff is linear. However, since 1/M = (1 minus κ eff )/g*, the plot will be linear only if g* is constant with κ eff . When g* increases with κ eff , the 1/M plot is said to be conservative because the critical mass is underestimated. However, it is possible for g* to decrease with κ eff yielding a nonconservative 1/M plot. A better understanding of g* would help predict whether a given approach to critical will be conservative or nonconservative. The equivalent fundamental-mode source strength g*S can be predicted by experiment. The experimental method was tested on the XIX-1 core on the Fast Critical Assembly at the Japan Atomic Energy Research Institute. The results showed a 30% difference between measured and calculated values. However, the XIX-1 reactor had significant intermediate-energy neutrons. The presence of intermediate-energy neutrons may have made the cross-section set used for predicted values less than ideal for the system

  20. A first level trigger approach for the CBM experiment

    International Nuclear Information System (INIS)

    Steinle, Christian Alexander

    2012-01-01

    In view of the very heavy CBM experiment constraints on the first level trigger, no conventional trigger is obviously applicable. Hence a fast trigger algorithm with the goal of realization in reconfigurable hardware had to be developed to fulfil all requirements of the experiment. In this connection the general Hough transform, which is already utilized in several other experiments, is used as a basis. This approach constitutes further a global method for tracking, which transforms all particle interaction points with the detector stations by means of a defined formula into a parameter space corresponding to the momentum of the particle tracks. This formula is of course developed especially for the given environment of CBM and defines thus the core of the applied three dimensional Hough transform. As the main focus of attention is furthermore on the realization of the needed data throughput, the necessary complex formula calculations give reason to outsource predefined formula results in look-up tables. This circumstance offers then collaterally the possibility to utilize any other sufficiently precise method like Runge-Kutta of fourth order for example to compute these look-up tables, because this computation can be evidently done offline without any effect on the Hough transform's processing speed. For algorithm simulation purposes the CBMROOT framework provides the module 'track', which is written in the programming language C++. This module includes many analyses for the determination of algorithm parameters, which can be even executed automatically to some extent. In addition to this, there are of course also analyses for the measurement of the algorithm's quality as well as for the individual rating of each partial step of the algorithm. Consequently the milestone of a customizable level one tracking algorithm, which can be used without any specific knowledge, is now obtained. Besides this, the investigated concepts are explicitly considered in the

  1. A first level trigger approach for the CBM experiment

    Energy Technology Data Exchange (ETDEWEB)

    Steinle, Christian Alexander

    2012-07-01

    In view of the very heavy CBM experiment constraints on the first level trigger, no conventional trigger is obviously applicable. Hence a fast trigger algorithm with the goal of realization in reconfigurable hardware had to be developed to fulfil all requirements of the experiment. In this connection the general Hough transform, which is already utilized in several other experiments, is used as a basis. This approach constitutes further a global method for tracking, which transforms all particle interaction points with the detector stations by means of a defined formula into a parameter space corresponding to the momentum of the particle tracks. This formula is of course developed especially for the given environment of CBM and defines thus the core of the applied three dimensional Hough transform. As the main focus of attention is furthermore on the realization of the needed data throughput, the necessary complex formula calculations give reason to outsource predefined formula results in look-up tables. This circumstance offers then collaterally the possibility to utilize any other sufficiently precise method like Runge-Kutta of fourth order for example to compute these look-up tables, because this computation can be evidently done offline without any effect on the Hough transform's processing speed. For algorithm simulation purposes the CBMROOT framework provides the module 'track', which is written in the programming language C++. This module includes many analyses for the determination of algorithm parameters, which can be even executed automatically to some extent. In addition to this, there are of course also analyses for the measurement of the algorithm's quality as well as for the individual rating of each partial step of the algorithm. Consequently the milestone of a customizable level one tracking algorithm, which can be used without any specific knowledge, is now obtained. Besides this, the investigated concepts are explicitly considered in the

  2. A first level trigger approach for the CBM experiment

    Energy Technology Data Exchange (ETDEWEB)

    Steinle, Christian Alexander

    2012-07-01

    In view of the very heavy CBM experiment constraints on the first level trigger, no conventional trigger is obviously applicable. Hence a fast trigger algorithm with the goal of realization in reconfigurable hardware had to be developed to fulfil all requirements of the experiment. In this connection the general Hough transform, which is already utilized in several other experiments, is used as a basis. This approach constitutes further a global method for tracking, which transforms all particle interaction points with the detector stations by means of a defined formula into a parameter space corresponding to the momentum of the particle tracks. This formula is of course developed especially for the given environment of CBM and defines thus the core of the applied three dimensional Hough transform. As the main focus of attention is furthermore on the realization of the needed data throughput, the necessary complex formula calculations give reason to outsource predefined formula results in look-up tables. This circumstance offers then collaterally the possibility to utilize any other sufficiently precise method like Runge-Kutta of fourth order for example to compute these look-up tables, because this computation can be evidently done offline without any effect on the Hough transform's processing speed. For algorithm simulation purposes the CBMROOT framework provides the module 'track', which is written in the programming language C++. This module includes many analyses for the determination of algorithm parameters, which can be even executed automatically to some extent. In addition to this, there are of course also analyses for the measurement of the algorithm's quality as well as for the individual rating of each partial step of the algorithm. Consequently the milestone of a customizable level one tracking algorithm, which can be used without any specific knowledge, is now obtained. Besides this, the investigated concepts are explicitly

  3. An approach to Poiseuille's law in an undergraduate laboratory experiment

    International Nuclear Information System (INIS)

    Sianoudis, I A; Drakaki, E

    2008-01-01

    The continuous growth of computer and sensor technology allows many researchers to develop simple modifications and/or refinements to standard educational experiments, making them more attractive and comprehensible to students and thus increasing their educational impact. In the framework of this approach, the present study proposes an alternative experimental setup, which allows the confirmation of Hagen-Poiseuille's law, governing the flow of real fluids through tubes, a law with numerous important applications in both technology and medicine. In the proposed educational procedure, experimental measurements of fluid outflow are performed with the use of a motion sensor and a suitable computer program, allowing the determination of both the hydrostatic pressure and the flow rate. The dependence of the flow rate on parameters such as viscosity of the fluid, length and radius of the tube and the pressure difference between the ends of the tube are also studied, providing a laboratory activity which is useful and attractive for first year students, especially those of technologically oriented departments

  4. Lagrangian Curves on Spectral Curves of Monopoles

    International Nuclear Information System (INIS)

    Guilfoyle, Brendan; Khalid, Madeeha; Ramon Mari, Jose J.

    2010-01-01

    We study Lagrangian points on smooth holomorphic curves in TP 1 equipped with a natural neutral Kaehler structure, and prove that they must form real curves. By virtue of the identification of TP 1 with the space LE 3 of oriented affine lines in Euclidean 3-space, these Lagrangian curves give rise to ruled surfaces in E 3 , which we prove have zero Gauss curvature. Each ruled surface is shown to be the tangent lines to a curve in E 3 , called the edge of regression of the ruled surface. We give an alternative characterization of these curves as the points in E 3 where the number of oriented lines in the complex curve Σ that pass through the point is less than the degree of Σ. We then apply these results to the spectral curves of certain monopoles and construct the ruled surfaces and edges of regression generated by the Lagrangian curves.

  5. Student Work Experience: A Realistic Approach to Merchandising Education.

    Science.gov (United States)

    Horridge, Patricia; And Others

    1980-01-01

    Relevant and realistic experiences are needed to prepare the student for a future career. Addresses the results of a survey of colleges and universities in the United States in regard to their student work experience (SWE) in fashion merchandising. (Author)

  6. Abordagem Bayesiana das curvas de crescimento de duas cultivares de feijoeiro Bayesian approach in the growth curves of two cultivars of common bean

    Directory of Open Access Journals (Sweden)

    Sebastião Martins Filho

    2008-09-01

    Full Text Available Neste trabalho foi utilizada a metodologia Bayesiana para ajustar o modelo não-linear logístico para dados de crescimento de duas cultivares de feijoeiro, "Neguinho" e "Carioca". O delineamento experimental utilizado foi o inteiramente casualizado, com vinte repetições, no esquema de parcelas subdivididas, sendo que os tratamentos principais foram constituídos pelas cultivares e as subparcelas foram constituídas por 17 períodos de avaliações, do plantio até aos 85 dias. A metodologia permitiu comparar as curvas de crescimentos sem utilizar a teoria assintótica e estes resultados mostraram um maior incremento em altura para a cultivar "Carioca".In this paper the Bayesian methodology was used to fit the logistic nonlinear model to growth data of two common bean cultivars, 'Neguinho' and 'Carioca'. The experiment was a split plot under a completely randomized design with twenty replicates, being the main treatments constituted by cultivars and the sub plots constituted by seventeen periods of evaluations, from planting to 85 days. The methodology allowed comparing the growth curves without using the asymptotic theory, and these results showed a larger height increment for the 'Carioca' cultivar.

  7. The national approach to radioactive waste management: the Philippine experience

    International Nuclear Information System (INIS)

    Valdezco, E.M.; Marcelo, E.A.; Junio, J.B.; Alamares, A.L.; Salom, D.S.

    1996-01-01

    The Philippine Nuclear Research Institute (PNRI), under the Department of Science and Technology (DOST) is tasked, among others, with the legally-mandated twin function of advancing and regulating the beneficial uses of nuclear energy and radiation technology. The PNRI is also responsible, among others, for the safe management of radioactive wastes generated by all licensed users of radioisotopes, including about 100 medical and industrial users. This papers describes the efforts taken by the PNRI, with technical assistance provided by the International Atomic Energy Agency to establish a low level radioactive waste management facility in the country and the subsequent upgrading of its waste management infrastructure. The conceptual approach and sebsequent implementation of the work programme is presented. Problems attendant to these efforts are briefly outlined including treatment methodologies for specific wastes. The commissioning and operational experiences using a batch type chemical precipitation plant appropriate for the volume of liquid wastes generated in the country is also presented. Data on radioactive waste arisings from 1980 are also presented including anticipated or projected wastes arisings should the repair of the PRR-1 (Philippine Research Reactor-1) research reactor be completed. The government initiatives towards the organizational development of a centralized waste management facility for low level wastes are also discussed. The formulation and adoption of a waste acceptance criteria and the R and D activities on various treatment procedures are also described. The current activities of the PNRI, as the lead agency in two important areas, one of which is in radioactive waste management, will be reported. National, regional and international cooperation in radioactive waste management will also be presented

  8. Extended analysis of cooling curves

    International Nuclear Information System (INIS)

    Djurdjevic, M.B.; Kierkus, W.T.; Liliac, R.E.; Sokolowski, J.H.

    2002-01-01

    Thermal Analysis (TA) is the measurement of changes in a physical property of a material that is heated through a phase transformation temperature range. The temperature changes in the material are recorded as a function of the heating or cooling time in such a manner that allows for the detection of phase transformations. In order to increase accuracy, characteristic points on the cooling curve have been identified using the first derivative curve plotted versus time. In this paper, an alternative approach to the analysis of the cooling curve has been proposed. The first derivative curve has been plotted versus temperature and all characteristic points have been identified with the same accuracy achieved using the traditional method. The new cooling curve analysis also enables the Dendrite Coherency Point (DCP) to be detected using only one thermocouple. (author)

  9. A Comparison of the Approaches to Customer Experience Analysis

    OpenAIRE

    Havíř David

    2017-01-01

    Nowadays, customer experience is receiving much attention in scientific and managerial community. Scholars and practitioners state that customer experience is the next area of competition. For a long time, there has been a call for a uniform, accurate definition, definition of its components, and the development of the customer experience frameworks. As this topic is new, there has been a considerable fragmentation. The question is if the fragmentation is still present and h...

  10. Statistical and biophysical aspects of survival curve

    International Nuclear Information System (INIS)

    Kellerer, A.M.

    1980-01-01

    Statistic fluctuation in a series of consequently taken survival curves of asynchronous cells of a hamster of the V79 line during X-ray irradiation, are considered. In each of the experiments fluctuations are close to those expected on the basis of the Poisson distribution. The fluctuation of cell sensitivity in different experiments of one series can reach 10%. The normalization of each experiment in mean values permits to obtain the ''idealized'' survival curve. The survival logarithm in this curve is proportional to the absorbed dose and its square only at low radiation doses. Such proportionality in V lab 79 cells in the late S-phase is observed at all doses. Using the microdosimetric approach, the distance where the interaction of radiolysis products or subinjury takes place to make the dependence of injury on the dose non-linear, is determined. In the case of interaction distances of 10-100 nm, the linear component is shown to become comparable in value with the linear injury component at doses of the order of several hundred rad only in the case, when the interaction distance is close to micrometre [ru

  11. Modern Approaches to Foreign Language Teaching: World Experience

    Science.gov (United States)

    Shumskyi, Oleksandr

    2016-01-01

    The problem of applying communicative approach to foreign language teaching of students in non-language departments of higher education institutions in a number of countries has been analyzed in the paper. The brief overview of main historic milestones in the development of communicative approach has been presented. It has been found out that…

  12. The adolescent experience in Juvenile Idiopathic Arthritis: A narrative approach

    NARCIS (Netherlands)

    Fuchs, C.E.

    2013-01-01

    This dissertation focused on the self-experience of adolescents with juvenile idiopathic arthritis (JIA) or chronic fatigue syndrome (CFS). Although the etiology and nosology of JIA and CFS are fundamentally different, some commonalities in the emotional experience of adolescents dealing with these

  13. Anatomical curve identification

    Science.gov (United States)

    Bowman, Adrian W.; Katina, Stanislav; Smith, Joanna; Brown, Denise

    2015-01-01

    Methods for capturing images in three dimensions are now widely available, with stereo-photogrammetry and laser scanning being two common approaches. In anatomical studies, a number of landmarks are usually identified manually from each of these images and these form the basis of subsequent statistical analysis. However, landmarks express only a very small proportion of the information available from the images. Anatomically defined curves have the advantage of providing a much richer expression of shape. This is explored in the context of identifying the boundary of breasts from an image of the female torso and the boundary of the lips from a facial image. The curves of interest are characterised by ridges or valleys. Key issues in estimation are the ability to navigate across the anatomical surface in three-dimensions, the ability to recognise the relevant boundary and the need to assess the evidence for the presence of the surface feature of interest. The first issue is addressed by the use of principal curves, as an extension of principal components, the second by suitable assessment of curvature and the third by change-point detection. P-spline smoothing is used as an integral part of the methods but adaptations are made to the specific anatomical features of interest. After estimation of the boundary curves, the intermediate surfaces of the anatomical feature of interest can be characterised by surface interpolation. This allows shape variation to be explored using standard methods such as principal components. These tools are applied to a collection of images of women where one breast has been reconstructed after mastectomy and where interest lies in shape differences between the reconstructed and unreconstructed breasts. They are also applied to a collection of lip images where possible differences in shape between males and females are of interest. PMID:26041943

  14. Differential geometry and topology of curves

    CERN Document Server

    Animov, Yu

    2001-01-01

    Differential geometry is an actively developing area of modern mathematics. This volume presents a classical approach to the general topics of the geometry of curves, including the theory of curves in n-dimensional Euclidean space. The author investigates problems for special classes of curves and gives the working method used to obtain the conditions for closed polygonal curves. The proof of the Bakel-Werner theorem in conditions of boundedness for curves with periodic curvature and torsion is also presented. This volume also highlights the contributions made by great geometers. past and present, to differential geometry and the topology of curves.

  15. The Rational Approach to Budget Cuts: One University's Experience.

    Science.gov (United States)

    Hardy, Cynthia

    1988-01-01

    The University of Montreal's choice of the rational model of decision-making in managing budget cutbacks is explored and compared with other approaches, including the bureaucratic, garbage can, political, and collegial models. (MSE)

  16. Western Scientific Approaches to Near-Death Experiences

    Directory of Open Access Journals (Sweden)

    Bruce Greyson

    2015-11-01

    Full Text Available Near-death experiences (NDEs are vivid experiences that often occur in life-threatening conditions, usually characterized by a transcendent tone and clear perceptions of leaving the body and being in a different spatiotemporal dimension. Such experiences have been reported throughout history in diverse cultures, and are reported today by 10% to 20% of people who have come close to death. Although cultural expectations and parameters of the brush with death influence the content of some NDEs, near-death phenomenology is invariant across cultures. That invariance may reflect universal psychological defenses, neurophysiological processes, or actual experience of a transcendent or mystical domain. Research into these alternative explanations has been hampered by the unpredictable occurrence of NDEs. Regardless of the causes or interpretations of NDEs, however, they are consistently associated with profound and long-lasting aftereffects on experiencers, and may have important implications for non-experiencers as well.

  17. Surgical experience with skull base approaches for foramen magnum meningioma.

    Science.gov (United States)

    Marin Sanabria, Elio Arnaldo; Ehara, Kazumasa; Tamaki, Norihiko

    2002-11-01

    The surgical treatment of patients with foramen magnum meningioma remains challenging. This study evaluated the outcome of this tumor according to the evolution of surgical approaches during the last 29 years. A retrospective analysis of medical records, operative notes, and neuroimages of 492 meningioma cases from 1972 to 2001 identified seven cases of foramen magnum meningioma (1.4%). All patients showed various neurological symptoms corresponding with foramen magnum syndrome. The tumor locations were anterior in five cases and posterior in two. Surgical removal was performed through a transoral approach in one patient, the suboccipital approach in three, and the transcondylar approach in two. Total removal was achieved in all patients, except for one who refused any surgical treatment. The major complications were tetraparesis and lower cranial nerve paresis for tumors in anterior locations, and minor complications for posterior locations. One patient died of atelectasis and pneumonia after a long hospitalization. The transcondylar approach is recommended for anterior locations, and the standard suboccipital approach for posterior locations.

  18. Approaching birds with drones: first experiments and ethical guidelines.

    Science.gov (United States)

    Vas, Elisabeth; Lescroël, Amélie; Duriez, Olivier; Boguszewski, Guillaume; Grémillet, David

    2015-02-01

    Unmanned aerial vehicles, commonly called drones, are being increasingly used in ecological research, in particular to approach sensitive wildlife in inaccessible areas. Impact studies leading to recommendations for best practices are urgently needed. We tested the impact of drone colour, speed and flight angle on the behavioural responses of mallards Anas platyrhynchos in a semi-captive situation, and of wild flamingos (Phoenicopterus roseus) and common greenshanks (Tringa nebularia) in a wetland area. We performed 204 approach flights with a quadricopter drone, and during 80% of those we could approach unaffected birds to within 4 m. Approach speed, drone colour and repeated flights had no measurable impact on bird behaviour, yet they reacted more to drones approaching vertically. We recommend launching drones farther than 100 m from the birds and adjusting approach distance according to species. Our study is a first step towards a sound use of drones for wildlife research. Further studies should assess the impacts of different drones on other taxa, and monitor physiological indicators of stress in animals exposed to drones according to group sizes and reproductive status. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  19. A new approach to experiments with non-relativistic antiprotons

    International Nuclear Information System (INIS)

    Poth, H.

    1990-05-01

    Is low-energy antiproton physics phasing out with the present round of experiments or are there good reasons to continue at an improved slow antiproton facility which could be located at a high intensity hadron accelerator? We point out, that there are four frontiers where substantial advances could be made. In particular, we discuss the low-energy frontier and emphasize that experiments with no-relativistic antiprotons would increase drastically the sensitivity and would reveal new effects. (orig.)

  20. Accessing the dynamics of end-grafted flexible polymer chains by atomic force-electrochemical microscopy. Theoretical modeling of the approach curves by the elastic bounded diffusion model and Monte Carlo simulations. Evidence for compression-induced lateral chain escape.

    Science.gov (United States)

    Abbou, Jeremy; Anne, Agnès; Demaille, Christophe

    2006-11-16

    The dynamics of a molecular layer of linear poly(ethylene glycol) (PEG) chains of molecular weight 3400, bearing at one end a ferrocene (Fc) label and thiol end-grafted at a low surface coverage onto a gold substrate, is probed using combined atomic force-electrochemical microscopy (AFM-SECM), at the scale of approximately 100 molecules. Force and current approach curves are simultaneously recorded as a force-sensing microelectrode (tip) is inserted within the approximately 10 nm thick, redox labeled, PEG chain layer. Whereas the force approach curve gives access to the structure of the compressed PEG layer, the tip-current, resulting from tip-to-substrate redox cycling of the Fc head of the chain, is controlled by chain dynamics. The elastic bounded diffusion model, which considers the motion of the Fc head as diffusion in a conformational field, complemented by Monte Carlo (MC) simulations, from which the chain conformation can be derived for any degree of confinement, allows the theoretical tip-current approach curve to be calculated. The experimental current approach curve can then be very satisfyingly reproduced by theory, down to a tip-substrate separation of approximately 2 nm, using only one adjustable parameter characterizing the chain dynamics: the effective diffusion coefficient of the chain head. At closer tip-substrate separations, an unpredicted peak is observed in the experimental current approach curve, which is shown to find its origin in a compression-induced escape of the chain from within the narrowing tip-substrate gap. MC simulations provide quantitative support for lateral chain elongation as the escape mechanism.

  1. Site characterization and validation - Tracer migration experiment in the validation drift, report 2, Part 2: breakthrough curves in the validation drift appendices 5-9

    International Nuclear Information System (INIS)

    Birgersson, L.; Widen, H.; Aagren, T.; Neretnieks, I.; Moreno, L.

    1992-01-01

    Flowrate curves for the 53 sampling areas in the validation drift with measureable flowrates are given. The sampling area 267 is treated as three separate sampling areas; 267:1, 267:2 and 267:3. The total flowrate for these three sampling areas is given in a separate plot. The flowrates are given in ml/h. The time is given in hours since April 27 00:00, 1990. Disturbances in flowrates are observed after 8500 hours due to opening of boreholes C1 and W1. Results from flowrate measurements after 8500 hours are therefore excluded. The tracer breakthrough curves for 38 sampling areas in the validation drift are given as concentration values versus time. The sampling area 267 is treated as three separate sampling areas; 267:1, 267:2 and 267:3. This gives a total of 40 breakthrough curves for each tracer. (au)

  2. Comparison of two methods to determine fan performance curves using computational fluid dynamics

    Science.gov (United States)

    Onma, Patinya; Chantrasmi, Tonkid

    2018-01-01

    This work investigates a systematic numerical approach that employs Computational Fluid Dynamics (CFD) to obtain performance curves of a backward-curved centrifugal fan. Generating the performance curves requires a number of three-dimensional simulations with varying system loads at a fixed rotational speed. Two methods were used and their results compared to experimental data. The first method incrementally changes the mass flow late through the inlet boundary condition while the second method utilizes a series of meshes representing the physical damper blade at various angles. The generated performance curves from both methods are compared with an experiment setup in accordance with the AMCA fan performance testing standard.

  3. COOPERATIVE APPROACH AND ICT: AN EXPERIENCE IN THE FL CLASSROOM

    Directory of Open Access Journals (Sweden)

    Severina Álvarez González

    2012-04-01

    Full Text Available Nowadays the  university educational  system  finds  itself  in  a  process  of  changes affecting the pedagogical scope. Bids are on new methodologies whose emphasis is made on open knowledge construction, cooperative learning and new resources and didactic tools: the use of ICT in the classroom. This paper shows the experience of a language classroom when implanting a didactic proposal including the use of ICT to provide cooperative learning among the students at the University of Oviedo. In order to value the results obtained by the experience in the FL teaching process, the students were asked to fill in a survey to express their  experiences  and  teachers  were  asked  to  daily  write  their  class  planning,  issues, motivations etc.

  4. ECM using Edwards curves

    DEFF Research Database (Denmark)

    Bernstein, Daniel J.; Birkner, Peter; Lange, Tanja

    2013-01-01

    -arithmetic level are as follows: (1) use Edwards curves instead of Montgomery curves; (2) use extended Edwards coordinates; (3) use signed-sliding-window addition-subtraction chains; (4) batch primes to increase the window size; (5) choose curves with small parameters and base points; (6) choose curves with large...

  5. EMPACT: An alternative approach to a high PT SSC experiment

    International Nuclear Information System (INIS)

    Marx, M.; State Univ. of New York, Stony Brook, NY

    1989-05-01

    A survey of high P T detector concepts advanced for the SSC reveals two striking facts -- first, the scale of most detectors is set by the muon detection system; and second, that the performance of these muon systems is limited in comparison to electron or jet capabilities, either in resolution or in rapidity acceptance. I propose here an alternative concept for an SSC experiment which will provide enhanced muon performance at a level to that obtainable through calorimetric means for electrons and jets, while drastically reducing the tonnage of the experiment

  6. Design of experiment approach for the process optimization of ...

    African Journals Online (AJOL)

    Mulberry is considered as food-medicine herb, with specific nutritional and medicinal values. In this study, response surface methodology (RSM) was employed to optimize the ultrasonic-assisted extraction of total polysaccharide from mulberry using Box-Behnken design (BBD). Based on single factor experiments, a three ...

  7. Subjective Experience of Episodic Memory and Metacognition: A Neurodevelopmental Approach

    Science.gov (United States)

    Souchay, Céline; Guillery-Girard, Bérengère; Pauly-Takacs, Katalin; Wojcik, Dominika Zofia; Eustache, Francis

    2013-01-01

    Episodic retrieval is characterized by the subjective experience of remembering. This experience enables the co-ordination of memory retrieval processes and can be acted on metacognitively. In successful retrieval, the feeling of remembering may be accompanied by recall of important contextual information. On the other hand, when people fail (or struggle) to retrieve information, other feelings, thoughts, and information may come to mind. In this review, we examine the subjective and metacognitive basis of episodic memory function from a neurodevelopmental perspective, looking at recollection paradigms (such as source memory, and the report of recollective experience) and metacognitive paradigms such as the feeling of knowing). We start by considering healthy development, and provide a brief review of the development of episodic memory, with a particular focus on the ability of children to report first-person experiences of remembering. We then consider neurodevelopmental disorders (NDDs) such as amnesia acquired in infancy, autism, Williams syndrome, Down syndrome, or 22q11.2 deletion syndrome. This review shows that different episodic processes develop at different rates, and that across a broad set of different NDDs there are various types of episodic memory impairment, each with possibly a different character. This literature is in agreement with the idea that episodic memory is a multifaceted process. PMID:24399944

  8. Effects of web experience on consumer choice: a multicultural approach

    NARCIS (Netherlands)

    Constantinides, Efthymios; Lorenzo Romero, Carlota; Gomez, Miguel A.

    2010-01-01

    Purpose – This paper seeks to analyze the buying behavior of internet users in two European countries with different cultural backgrounds, Spain and The Netherlands, assessing the influence of online experience factors on the choice of an internet vendor. It also aims to identify and compare the

  9. An Approach Toward Synthesis of Bridgmanite in Dynamic Compression Experiments

    Science.gov (United States)

    Reppart, J. J.

    2015-12-01

    Bridgmanite occurs in heavily shocked meteorites and provides a useful constraint on pressure-temperature conditions during shock-metamorphism. Its occurrence also provides constraints on the shock release path. Shock-release and shock duration are important parameters in estimating the size of impactors that generate the observed shock metamorphic record. Thus, it is timely to examine if bridgmanite can be synthesized in dynamic compression experiments with the goal of establishing a correlation between shock duration and grainsize. Up to now only one high pressure polymorph of an Mg-silicate has been synthesized AND recovered in a shock experiment (wadsleyite). Therefore, it is not given that shock synthesis of bridgmanite is possible. This project started recently, so we present an outline of shock experiment designs and potentially results from the first experiments. FUNDING ACKNOWLEDGMENT UNLV HiPSEC: This research was sponsored (or sponsored in part) by the National Nuclear Security Administration under the Stewardship Science Academic Alliances program through DOE Cooperative Agreement #DE-NA0001982. HPCAT: "[Portions of this work were]/[This work was] performed at HPCAT (Sector 16), Advanced Photon Source (APS), Argonne National Laboratory. HPCAT operations are supported by DOE-NNSA under Award No. DE-NA0001974 and DOE-BES under Award No. DE-FG02-99ER45775, with partial instrumentation funding by NSF. APS is supported by DOE-BES, under Contract No. DE-AC02-06CH11357."

  10. Completion of the first approach to critical for the seven percent critical experiment

    International Nuclear Information System (INIS)

    Barber, A. D.; Harms, G. A.

    2009-01-01

    The first approach-to-critical experiment in the Seven Percent Critical Experiment series was recently completed at Sandia. This experiment is part of the Seven Percent Critical Experiment which will provide new critical and reactor physics benchmarks for fuel enrichments greater than five weight percent. The inverse multiplication method was used to determine the state of the system during the course of the experiment. Using the inverse multiplication method, it was determined that the critical experiment went slightly supercritical with 1148 fuel elements in the fuel array. The experiment is described and the results of the experiment are presented. (authors)

  11. Serial position curves in free recall.

    Science.gov (United States)

    Laming, Donald

    2010-01-01

    The scenario for free recall set out in Laming (2009) is developed to provide models for the serial position curves from 5 selected sets of data, for final free recall, and for multitrial free recall. The 5 sets of data reflect the effects of rate of presentation, length of list, delay of recall, and suppression of rehearsal. Each model accommodates the serial position curve for first recalls (where those data are available) as well as that for total recalls. Both curves are fit with the same parameter values, as also (with 1 exception) are all of the conditions compared within each experiment. The distributions of numbers of recalls are also examined and shown to have variances increased above what would be expected if successive recalls were independent. This is taken to signify that, in those experiments in which rehearsals were not recorded, the retrieval of words for possible recall follows the same pattern that is observed following overt rehearsal, namely, that retrieval consists of runs of consecutive elements from memory. Finally, 2 sets of data are examined that the present approach cannot accommodate. It is argued that the problem with these data derives from an interaction between the patterns of (covert) rehearsal and the parameters of list presentation.

  12. Learning from project experiences using a legacy-based approach

    Science.gov (United States)

    Cooper, Lynne P.; Majchrzak, Ann; Faraj, Samer

    2005-01-01

    As project teams become used more widely, the question of how to capitalize on the knowledge learned in project teams remains an open issue. Using previous research on shared cognition in groups, an approach to promoting post-project learning was developed. This Legacy Review concept was tested on four in tact project teams. The results from those test sessions were used to develop a model of team learning via group cognitive processes. The model and supporting propositions are presented.

  13. A new approach for a pump-probe photothermal experiment

    International Nuclear Information System (INIS)

    Marcano O, A.; Castillo, J.

    1992-01-01

    Calculations of the signal, observed in a pump-probe photo-thermal experimental, are performed using a close field nonlinear geometrical optics approximation. Dependence of the thermo-optical signal from the position of the detector and magnitude of the beams spots size is studied. It is shown that the possibilities of the thermo-optical experiment, as a highly sensitive technique for light detection, can be substantially improved by increasing the probe beam spot size and varying the position of the detector in the vicinity of the sample cell. preliminary experimental results are shown for the situation of weak absorbing liquids. A good qualitative agreement between theory and experiments is obtained. (author)

  14. An Initial Approach for Learning Objects from Experience

    Science.gov (United States)

    2018-05-02

    algorithm to delineate objects which are then fed to a simple feed-forward neural network without any other processes in the pipeline. Our neural network...These are the basic requirements for the pipeline and are discussed in more detail below. Additionally, we are interested in testing various parts...that continuously learning objects from experience requires mechanisms to do the following: 1) Focus attention on things and stuff of interest . 2

  15. [A Grounded Theory Approach on Nurses' Experience with Workplace Bullying].

    Science.gov (United States)

    Kang, Jiyeon; Yun, Seonyoung

    2016-04-01

    The purpose of this qualitative study was to explore the workplace bullying experience of Korean nurses. Participants were twenty current or former hospital nurses who had experienced workplace bullying. Data were collected through focus group and individual in-depth interviews from February to May, 2015. Theoretical sampling method was applied to the point of theoretical saturation. Transcribed interview contents were analyzed using Corbin and Strauss's grounded theory method. A total of 110 concepts, 48 sub-categories, and 17 categories were identified through the open coding process. As a result of axial coding based on the paradigm model, the central phenomenon of nurses' workplace bullying experience was revealed as 'teaching that has become bullying', and the core category was extracted as 'surviving in love-hate teaching' consisting of a four-step process: confronting reality, trial and error, relationship formation, and settlement. The relationship formation was considered to be the key phase to proceed to the positive settlement phase, and the participants utilized various strategies such as having an open mind, developing human relationships, understanding each other in this phase. The in-depth understanding of the workplace bullying experience has highlighted the importance of effective communication for cultivating desirable human relationships between nurses.

  16. Technician support for operation and maintenance of large fusion experiments: the tandem mirror experiment upgrade (TMX-U) approach

    International Nuclear Information System (INIS)

    Mattson, G.E.

    1983-01-01

    As experiments continue to grow in size and complexity, a few technicians will no longer be able to maintain and operate the complete experiment. Specialization is becoming the norm. Subsystems are becoming very large and complex, requiring a great deal of experience and training for technicians to become qualified maintenance/operation personnel. Formal in-house and off-site programs supplement on-the-job training to fulfill the qualification criteria. This paper presents the Tandem Mirror Experiment-Upgrade (TMX-U) approach to manpower staffing, some problems encountered, possible improvements, and safety considerations for the successful operation of a large experimental facility

  17. Relations between the development of school investment, self-confidence, and language achievement in elementary education: A multivariate latent growth curve approach

    NARCIS (Netherlands)

    Stoel, R.D.; Peetsma, T.T.D.; Roeleveld, J.

    2001-01-01

    Latent growth curve (LGC) analysis of longitudinal data for pupils' school investment, self confidence and language ability is presented. A multivariate model is tested that relates the three developmental processes to each other and to intelligence. All processes show significant differences

  18. Unveiling multiple solid-state transitions in pharmaceutical solid dosage forms using multi-series hyperspectral imaging and different curve resolution approaches

    DEFF Research Database (Denmark)

    Alexandrino, Guilherme L; Amigo Rubio, Jose Manuel; Khorasani, Milad Rouhi

    2017-01-01

    Solid-state transitions at the surface of pharmaceutical solid dosage forms (SDF) were monitored using multi-series hyperspectral imaging (HSI) along with Multivariate Curve Resolution – Alternating Least Squares (MCR-ALS) and Parallel Factor Analysis (PARAFAC and PARAFAC2). First, the solid-stat...

  19. A curve-fitting approach to estimate the arterial plasma input function for the assessment of glucose metabolic rate and response to treatment.

    NARCIS (Netherlands)

    Vriens, D.; Geus-Oei, L.F. de; Oyen, W.J.G.; Visser, E.P.

    2009-01-01

    For the quantification of dynamic (18)F-FDG PET studies, the arterial plasma time-activity concentration curve (APTAC) needs to be available. This can be obtained using serial sampling of arterial blood or an image-derived input function (IDIF). Arterial sampling is invasive and often not feasible

  20. Model-based Approach for Long-term Creep Curves of Alloy 617 for a High Temperature Gas-cooled Reactor

    International Nuclear Information System (INIS)

    Kim, Woo Gon; Yin, Song Nan; Kim, Yong Wan

    2008-01-01

    Alloy 617 is a principal candidate alloy for the high temperature gas-cooled reactor (HTGR) components, because of its high creep rupture strength coupled with its good corrosion behavior in simulated HTGR-helium and its sufficient workability. To describe a creep strain-time curve well, various constitutive equations have been proposed by Kachanov-Rabotnov, Andrade, Garofalo, Evans and Maruyama, et al.. Among them, the K-R model has been used frequently, because a secondary creep resulting from a balance between a softening and a hardening of materials and a tertiary creep resulting from an appearance and acceleration of the internal or external damage processes are adequately considered. In the case of nickel-base alloys, it has been reported that a tertiary creep at a low strain range may be generated, and this tertiary stage may govern the total creep deformation. Therefore, a creep curve for nickel-based Alloy 617 will be predicted appropriately by using the K-R model that can reflect a tertiary creep. In this paper, the long-term creep curves for Alloy 617 were predicted by using the nonlinear least square fitting (NLSF) method in the K-R model. The modified K-R model was introduced to fit the full creep curves well. The values for the λ and K parameters in the modified K-R model were obtained with stresses

  1. Sex separation strategies: past experience and new approaches

    Directory of Open Access Journals (Sweden)

    Malcolm Colin A

    2009-11-01

    Full Text Available Abstract The success of the sterile insect technique (SIT and other genetic strategies designed to eliminate large populations of insects relies on the efficient inundative releases of competitive, sterile males into the natural habitat of the target species. As released sterile females do not contribute to the sterility in the field population, systems for the efficient mass production and separation of males from females are needed. For vector species like mosquitoes, in which only females bite and transmit diseases, the thorough removal of females before release while leaving males competent to mate is a stringent prerequisite. Biological, genetic and transgenic approaches have been developed that permit efficient male-female separation for some species considered for SIT. However, most sex separation methods have drawbacks and many of these methods are not directly transferable to mosquitoes. Unlike genetic and transgenic systems, biological methods that rely on sexually dimorphic characters, such as size or development rate, are subject to natural variation, requiring regular adjustment and re-calibration of the sorting systems used. The yield can be improved with the optimization of rearing, but the scale of mass production places practical limits on what is achievable, resulting in a poor rearing to output ratio. High throughput separation is best achieved with scalable genetic or transgenic approaches.

  2. Theoretical melting curve of caesium

    International Nuclear Information System (INIS)

    Simozar, S.; Girifalco, L.A.; Pennsylvania Univ., Philadelphia

    1983-01-01

    A statistical-mechanical model is developed to account for the complex melting curve of caesium. The model assumes the existence of three different species of caesium defined by three different electronic states. On the basis of this model, the free energy of melting and the melting curve are computed up to 60 kbar, using the solid-state data and the initial slope of the fusion curve as input parameters. The calculated phase diagram agrees with experiment to within the experimental error. Other thermodynamic properties including the entropy and volume of melting were also computed, and they agree with experiment. Since the theory requires only one adjustable constant, this is taken as strong evidence that the three-species model is satisfactory for caesium. (author)

  3. Information Ergonomics A theoretical approach and practical experience in transportation

    CERN Document Server

    Sandl, Peter

    2012-01-01

    The variety and increasing availability of hypermedia information systems, which are used in stationary applications like operators’ consoles as well as mobile systems, e.g. driver information and navigation systems in automobiles form a foundation for the mediatization of the society. From the human engineering point of view this development and the ensuing increased importance of information systems for economic and private needs require careful deliberation of the derivation and application of ergonomics methods particularly in the field of information systems. This book consists of two closely intertwined parts. The first, theoretical part defines the concept of an information system, followed by an explanation of action regulation as well as cognitive theories to describe man information system interaction. A comprehensive description of information ergonomics concludes the theoretical approach. In the second, practically oriented part of this book authors from industry as well as from academic institu...

  4. Tourism and international business: The theoretical approach and practical experiences

    Directory of Open Access Journals (Sweden)

    Jovičić Dobrica

    2011-01-01

    Full Text Available The paper discusses the relationships between tourism and international business. The research is based upon combining various theoretical concepts, significant empirical experiences and own attitudes of the authors. The key conclusion of the paper is that, despite of the partial progress in understanding tourism businesses, the relationships between tourism and international business need additional stimulus. In other words, more complete research in the related domains is needed in future. Any understanding of tourism is inadequate without appreciating the contributions that international business might bring, yet at the same time international business is incomplete in its coverage of international trade unless tourism is considered. The consumption-driven agenda of much tourism research has been favoured over supply-side discourses of the production process it self. That is why the role of major transnational companies, setting the trends that other types of firms in the tourism sector follow is focused in the paper.

  5. Experience Studies on Determining Life Premium Insurance Ratings: Practical Approaches

    Directory of Open Access Journals (Sweden)

    Mirela CRISTEA

    2008-01-01

    Full Text Available The focus of this article is to present the modelling tehcniques used on international practice in the evaluation of right life premiums based. The knowledge and models obtained have a common element of mortality risk indicators but these are varied in different parts of the world. The common elements of these studies and models are generally based on a series of indicators which mainly point out their probability of survival and they are named the mortality indicators. These indicators represent the basis for the calculation of the premiums quotes and for the elaboration by the insurers of premium tables. The benefit for the policyholder is to obtain insurance at a fair and competitive price and for the insurer, to maintain the experience of its portfolio in line with mortality assumptions.

  6. Contractibility of curves

    Directory of Open Access Journals (Sweden)

    Janusz Charatonik

    1991-11-01

    Full Text Available Results concerning contractibility of curves (equivalently: of dendroids are collected and discussed in the paper. Interrelations tetween various conditions which are either sufficient or necessary for a curve to be contractible are studied.

  7. Public health approach to birth defects: the Argentine experience.

    Science.gov (United States)

    Bidondo, María Paz; Groisman, Boris; Barbero, Pablo; Liascovich, Rosa

    2015-04-01

    Birth defects are a global problem, but their impact is particularly severe in low and middle income countries, where the conditions for prevention, treatment, and rehabilitation are more critical. The epidemiological transition in the infant mortality causes, and the concern of the community and the mass media about the teratogenic risk of environmental pollutants, has made health authorities aware of the importance of birth defects in Argentina. The objective of this paper is to outline those actions specifically taken in Argentina aimed at the prevention of birth defects at a national level. Firstly, we focus on birth defects in Argentina on a general basis, and then we present different laws and actions taken in terms of surveillance and public health programs, primary, secondary, and tertiary prevention. Finally, we present the Teratology Information Service "Fetal Health Line", and the genetic services organization and health professionals training by the National Center of Medical Genetics and the National Program of Genetics Network. In conclusion, in the country, several programs focus on different approaches to the problem, and the challenge is to coordinate the teamwork between them. Finally, we list tips to address birth defects from the public health perspective.

  8. Radial artery approach for coronary intervention - early experience

    International Nuclear Information System (INIS)

    Jan, H.; Hadi, A.; Fahim, M.; Gul, A.M.; Irfan, M.; Khan, S.B.; Hafizullah, M.

    2012-01-01

    Objective: To see the clinical outcome of patients undergoing Transradial Coronary Angioplasty with stable Angina. Methodology: This was a single center observational study with prospective data collection of 338 patients who underwent transradial coronary angioplasty from September 2009 to August 2011, at Post Graduate Medical Institute, Lady Reading Hospital, Peshawar. Patients of both genders and all ages who had transradial coronary angioplasty for chronic stable angina were included in the study. Patients were clinically examined in out patients department on first month of hospital discharge and clinical outcome data was recorded. Results: A total of 338 patients were included in the study. Male were 58.8% and 41.2% were female with mean age of 52+-7 years. All the patients had coronary intervention through right radial artery. Baseline characteristics of the patients were; 48.2% diabetic, 43.2% hypertensive, 30.5% smokers, dyslipidemia was 45.7% and mean values of serum creatinine and Hemoglobin were 1.1+-0.3 and 11.5+-1.5, respectively. The frequency of various complications were as follow; hematoma 1.3%, nausea and vomiting 2.2%, pain in hand 11.2%, re admission to hospital for chest pain 6.5%, need for revascularization 2.2%, hand ischemia 1.8%, minor bleeding 0.9%, no major bleeding and 1.9% mortality. Conclusion: The radial artery approach for coronary intervention is useful with low degree of access site vascular complications and an early mobilization. (author)

  9. Radial artery approach for coronary intervention - early experience

    Energy Technology Data Exchange (ETDEWEB)

    Jan, H; Hadi, A; Fahim, M; Gul, A M; Irfan, M; Khan, S B; Hafizullah, M [Lady Reading Hospital and Khyber Medical University, Peshawar (Pakistan). Dept. of Cardiology

    2012-01-15

    Objective: To see the clinical outcome of patients undergoing Transradial Coronary Angioplasty with stable Angina. Methodology: This was a single center observational study with prospective data collection of 338 patients who underwent transradial coronary angioplasty from September 2009 to August 2011, at Post Graduate Medical Institute, Lady Reading Hospital, Peshawar. Patients of both genders and all ages who had transradial coronary angioplasty for chronic stable angina were included in the study. Patients were clinically examined in out patients department on first month of hospital discharge and clinical outcome data was recorded. Results: A total of 338 patients were included in the study. Male were 58.8% and 41.2% were female with mean age of 52+-7 years. All the patients had coronary intervention through right radial artery. Baseline characteristics of the patients were; 48.2% diabetic, 43.2% hypertensive, 30.5% smokers, dyslipidemia was 45.7% and mean values of serum creatinine and Hemoglobin were 1.1+-0.3 and 11.5+-1.5, respectively. The frequency of various complications were as follow; hematoma 1.3%, nausea and vomiting 2.2%, pain in hand 11.2%, re admission to hospital for chest pain 6.5%, need for revascularization 2.2%, hand ischemia 1.8%, minor bleeding 0.9%, no major bleeding and 1.9% mortality. Conclusion: The radial artery approach for coronary intervention is useful with low degree of access site vascular complications and an early mobilization. (author)

  10. Attitudes towards honey among Italian consumers: A choice experiment approach.

    Science.gov (United States)

    Cosmina, Marta; Gallenti, Gianluigi; Marangon, Francesco; Troiano, Stefania

    2016-04-01

    Honey is becoming increasingly popular with consumers for its nutritional benefits as well as many other functions. The objective of this article is to determine which factors influence consumers' purchase intentions and to assess the importance of certain honey characteristics to enable identification of the constituents of an ideal honey profile. This information will lead to satisfaction of consumers' preferences and formulation of marketing strategies that support honey makers. We applied a choice experiment to the Italian honey market to define the preferences and the willingness to pay for key characteristics of the product. A face-to-face questionnaire survey was conducted in 2014 (January-July) among Italian consumers; it was completed by 427 respondents. A latent class model was estimated and four classes were identified, with different preferences, illustrating that respondents seem to be heterogeneous honey consumers. Results suggest the "organic" attribute was more important than others factors, such as the place where the honey was produced (landscape), but less important than the country of origin; local Italian honey was preferred to foreign honey. Respondents showed a higher willingness to pay (WTP) for honey from their country of origin versus the production method used. Our results suggest that while organic beekeeping might be an important strategy for diversification, if suitable communication is not taken into consideration, the added value of the production method might not be perceived by consumers. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Design and analysis of experiments classical and regression approaches with SAS

    CERN Document Server

    Onyiah, Leonard C

    2008-01-01

    Introductory Statistical Inference and Regression Analysis Elementary Statistical Inference Regression Analysis Experiments, the Completely Randomized Design (CRD)-Classical and Regression Approaches Experiments Experiments to Compare Treatments Some Basic Ideas Requirements of a Good Experiment One-Way Experimental Layout or the CRD: Design and Analysis Analysis of Experimental Data (Fixed Effects Model) Expected Values for the Sums of Squares The Analysis of Variance (ANOVA) Table Follow-Up Analysis to Check fo

  12. Disadvantages of using the area under the receiver operating characteristic curve to assess imaging tests: A discussion and proposal for an alternative approach

    International Nuclear Information System (INIS)

    Halligan, Steve; Altman, Douglas G.; Mallett, Susan

    2015-01-01

    The objectives are to describe the disadvantages of the area under the receiver operating characteristic curve (ROC AUC) to measure diagnostic test performance and to propose an alternative based on net benefit. We use a narrative review supplemented by data from a study of computer-assisted detection for CT colonography. We identified problems with ROC AUC. Confidence scoring by readers was highly non-normal, and score distribution was bimodal. Consequently, ROC curves were highly extrapolated with AUC mostly dependent on areas without patient data. AUC depended on the method used for curve fitting. ROC AUC does not account for prevalence or different misclassification costs arising from false-negative and false-positive diagnoses. Change in ROC AUC has little direct clinical meaning for clinicians. An alternative analysis based on net benefit is proposed, based on the change in sensitivity and specificity at clinically relevant thresholds. Net benefit incorporates estimates of prevalence and misclassification costs, and it is clinically interpretable since it reflects changes in correct and incorrect diagnoses when a new diagnostic test is introduced. ROC AUC is most useful in the early stages of test assessment whereas methods based on net benefit are more useful to assess radiological tests where the clinical context is known. Net benefit is more useful for assessing clinical impact. (orig.)

  13. Multidisciplinary Approach to Esophageal Achalasia: A Single Center Experience.

    Science.gov (United States)

    Schlottmann, Francisco; Andolfi, Ciro; Kavitt, Robert T; Konda, Vani J A; Patti, Marco G

    2017-04-01

    The treatment of achalasia is palliative. Pneumatic dilatation (PD) or laparoscopic Heller myotomy (LHM) just eliminates the outflow obstruction allowing easier emptying of the esophagus. The aim of this study was to evaluate the results of a multidisciplinary approach to esophageal achalasia. A consecutive series of patients with achalasia treated by a multidisciplinary esophageal team consisting of radiologists, gastroenterologists, and surgeons in a quaternary care center between May 2008 and April 2015 were analyzed. A total of 147 patients with achalasia underwent LHM and partial fundoplication. Sixty-two patients (42%) had been treated preoperatively with PD and/or botulinum toxin (BT). The preoperative Eckardt score (ES) was 6.4 ± 2. At a median follow-up of 22 months, 128 patients (87%) did well and required no further treatment (ES 0.1). The remaining 19 patients (13%) had recurrence of symptoms and required further treatment: 12 were treated with PD and improved (ES 0.7); 4 were treated with PD and BT and improved (ES 1.3); 3 failed PD. These 3 patients had been treated with multiple sessions of PD and BT before the myotomy. Overall, 144 patients (98%) did well with laparoscopic (87%) or laparoscopic and endoscopic treatment (11%). The results of this study show that (a) LHM is an effective treatment modality, (b) PD improved symptoms in the majority of patients with recurrent dysphagia after myotomy and (c) multiple preoperative endoscopic treatments seem to affect outcomes of LHM. Patients with achalasia should be treated in a quaternary care center by a multidisciplinary team.

  14. The New Keynesian Phillips Curve

    DEFF Research Database (Denmark)

    Ólafsson, Tjörvi

    This paper provides a survey on the recent literature on the new Keynesian Phillips curve: the controversies surrounding its microfoundation and estimation, the approaches that have been tried to improve its empirical fit and the challenges it faces adapting to the open-economy framework. The new......, learning or state-dependant pricing. The introduction of openeconomy factors into the new Keynesian Phillips curve complicate matters further as it must capture the nexus between price setting, inflation and the exchange rate. This is nevertheless a crucial feature for any model to be used for inflation...... forecasting in a small open economy like Iceland....

  15. Surface-treated self-standing curved crystals as high-efficiency elements for X- and γ-ray optics: theory and experiment.

    Science.gov (United States)

    Bonnini, Elisa; Buffagni, Elisa; Zappettini, Andrea; Doyle, Stephen; Ferrari, Claudio

    2015-06-01

    The efficiency of a Laue lens for X- and γ-ray focusing in the energy range 60-600 keV is closely linked to the diffraction efficiency of the single crystals composing the lens. A powerful focusing system is crucial for applications like medical imaging and X-ray astronomy where wide beams must be focused. Mosaic crystals with a high density, such as Cu or Au, and bent crystals with curved diffracting planes (CDPs) are considered for the realization of a focusing system for γ-rays, owing to their high diffraction efficiency in a predetermined angular range. In this work, a comparison of the efficiency of CDP crystals and Cu and Au mosaic crystals was performed on the basis of the theory of X-ray diffraction. Si, GaAs and Ge CDP crystals with optimized thicknesses and moderate radii of curvature of several tens of metres demonstrate comparable or superior performance with respect to the higher atomic number mosaic crystals generally used. In order to increase the efficiency of the lens further, a stack of several CDP crystals is proposed as an optical element. CDP crystals were obtained by a surface-damage method, and a stack of two surface-damaged bent Si crystals was prepared and tested. Rocking curves of the stack were performed with synchrotron radiation at 19 keV to check the lattice alignment: they exhibited only one diffraction peak.

  16. Materials for pressure equipment under the new approach directives: a one-year home-experience

    International Nuclear Information System (INIS)

    Zdankiewicz, M.

    2005-01-01

    The New Approach Directives concerning pressure equipment set forth basic safety requirements for their designing, manufacturing and testing. The said requirements are being implemented in the field of materials in Poland after one-year experience. (author)

  17. Experience transfer in Norwegian oil and gas industry: Approaches and organizational mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Aase, Karina

    1997-12-31

    The main objective of this thesis has been to explore how experience transfer works in Norwegian oil and gas industry. This includes how the concept of experience transfer is defined, what the barriers to achieve experience transfer are, how the oil and gas companies address experience transfer, and how these approaches work. The thesis is organized in five papers: (1) describes how organizational members perceive experience transfer and then specifies the organizational and structural barriers that must be overcome to achieve efficient transfer. (2) discusses the organizational means an oil company implements to address experience transfer. (3) describes a process of improving and using requirement and procedure handbooks for experience transfer. (4) explores how the use of information technology influences experience transfer. (5) compares organizational members` perceptions of experience transfer means in an oil company and an engineering company involved in offshore development projects. 277 refs., 3 figs., 29 tabs.

  18. Experience transfer in Norwegian oil and gas industry: Approaches and organizational mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Aase, Karina

    1998-12-31

    The main objective of this thesis has been to explore how experience transfer works in Norwegian oil and gas industry. This includes how the concept of experience transfer is defined, what the barriers to achieve experience transfer are, how the oil and gas companies address experience transfer, and how these approaches work. The thesis is organized in five papers: (1) describes how organizational members perceive experience transfer and then specifies the organizational and structural barriers that must be overcome to achieve efficient transfer. (2) discusses the organizational means an oil company implements to address experience transfer. (3) describes a process of improving and using requirement and procedure handbooks for experience transfer. (4) explores how the use of information technology influences experience transfer. (5) compares organizational members` perceptions of experience transfer means in an oil company and an engineering company involved in offshore development projects. 277 refs., 3 figs., 29 tabs.

  19. A curve-fitting approach to estimate the arterial plasma input function for the assessment of glucose metabolic rate and response to treatment.

    Science.gov (United States)

    Vriens, Dennis; de Geus-Oei, Lioe-Fee; Oyen, Wim J G; Visser, Eric P

    2009-12-01

    For the quantification of dynamic (18)F-FDG PET studies, the arterial plasma time-activity concentration curve (APTAC) needs to be available. This can be obtained using serial sampling of arterial blood or an image-derived input function (IDIF). Arterial sampling is invasive and often not feasible in practice; IDIFs are biased because of partial-volume effects and cannot be used when no large arterial blood pool is in the field of view. We propose a mathematic function, consisting of an initial linear rising activity concentration followed by a triexponential decay, to describe the APTAC. This function was fitted to 80 oncologic patients and verified for 40 different oncologic patients by area-under-the-curve (AUC) comparison, Patlak glucose metabolic rate (MR(glc)) estimation, and therapy response monitoring (Delta MR(glc)). The proposed function was compared with the gold standard (serial arterial sampling) and the IDIF. To determine the free parameters of the function, plasma time-activity curves based on arterial samples in 80 patients were fitted after normalization for administered activity (AA) and initial distribution volume (iDV) of (18)F-FDG. The medians of these free parameters were used for the model. In 40 other patients (20 baseline and 20 follow-up dynamic (18)F-FDG PET scans), this model was validated. The population-based curve, individually calibrated by AA and iDV (APTAC(AA/iDV)), by 1 late arterial sample (APTAC(1 sample)), and by the individual IDIF (APTAC(IDIF)), was compared with the gold standard of serial arterial sampling (APTAC(sampled)) using the AUC. Additionally, these 3 methods of APTAC determination were evaluated with Patlak MR(glc) estimation and with Delta MR(glc) for therapy effects using serial sampling as the gold standard. Excellent individual fits to the function were derived with significantly different decay constants (P AUC from APTAC(AA/iDV), APTAC(1 sample), and APTAC(IDIF) with the gold standard (APTAC(sampled)) were 0

  20. Migration and the Wage Curve:

    DEFF Research Database (Denmark)

    Brücker, Herbert; Jahn, Elke J.

    in a general equilibrium framework. For the empirical analysis we employ the IABS, a two percent sample of the German labor force. We find that the elasticity of the wage curve is particularly high for young workers and workers with a university degree, while it is low for older workers and workers......  Based on a wage curve approach we examine the labor market effects of migration in Germany. The wage curve relies on the assumption that wages respond to a change in the unemployment rate, albeit imperfectly. This allows one to derive the wage and employment effects of migration simultaneously...... with a vocational degree. The wage and employment effects of migration are moderate: a 1 percent increase in the German labor force through immigration increases the aggregate unemployment rate by less than 0.1 percentage points and reduces average wages by less 0.1 percent. While native workers benefit from...

  1. Complexity of Curved Glass Structures

    Science.gov (United States)

    Kosić, T.; Svetel, I.; Cekić, Z.

    2017-11-01

    Despite the increasing number of research on the architectural structures of curvilinear forms and technological and practical improvement of the glass production observed over recent years, there is still a lack of comprehensive codes and standards, recommendations and experience data linked to real-life curved glass structures applications regarding design, manufacture, use, performance and economy. However, more and more complex buildings and structures with the large areas of glass envelope geometrically complex shape are built every year. The aim of the presented research is to collect data on the existing design philosophy on curved glass structure cases. The investigation includes a survey about how architects and engineers deal with different design aspects of curved glass structures with a special focus on the design and construction process, glass types and structural and fixing systems. The current paper gives a brief overview of the survey findings.

  2. Three-Hand Endoscopic Endonasal Transsphenoidal Surgery: Experience With an Anatomy-Preserving Mononostril Approach Technique.

    Science.gov (United States)

    Eseonu, Chikezie I; ReFaey, Karim; Pamias-Portalatin, Eva; Asensio, Javier; Garcia, Oscar; Boahene, Kofi D; Quiñones-Hinojosa, Alfredo

    2018-02-01

    Variations on the endoscopic transsphenoidal approach present unique surgical techniques that have unique effects on surgical outcomes, extent of resection (EOR), and anatomical complications. To analyze the learning curve and perioperative outcomes of the 3-hand endoscopic endonasal mononostril transsphenoidal technique. Prospective case series and retrospective data analysis of patients who were treated with the 3-hand transsphenoidal technique between January 2007 and May 2015 by a single neurosurgeon. Patient characteristics, preoperative presentation, tumor characteristics, operative times, learning curve, and postoperative outcomes were analyzed. Volumetric EOR was evaluated, and a logistic regression analysis was used to assess predictors of EOR. Two hundred seventy-five patients underwent an endoscopic transsphenoidal surgery using the 3-hand technique. One hundred eighteen patients in the early group had surgery between 2007 and 2010, while 157 patients in the late group had surgery between 2011 and 2015. Operative time was significantly shorter in the late group (161.6 min) compared to the early group (211.3 min, P = .001). Both cohorts had similar EOR (early group 84.6% vs late group 85.5%, P = .846) and postoperative outcomes. The learning curve showed that it took 54 cases to achieve operative proficiency with the 3-handed technique. Multivariate modeling suggested that prior resections and preoperative tumor size are important predictors for EOR. We describe a 3-hand, mononostril endoscopic transsphenoidal technique performed by a single neurosurgeon that has minimal anatomic distortion and postoperative complications. During the learning curve of this technique, operative time can significantly decrease, while EOR, postoperative outcomes, and complications are not jeopardized. Copyright © 2017 by the Congress of Neurological Surgeons

  3. Understanding the adsorptive interactions of arsenate-iron nanoparticles with curved fullerene-like sheets in activated carbon using a quantum mechanics/molecular mechanics computational approach.

    Science.gov (United States)

    Ha, Nguyen Ngoc; Cam, Le Minh; Ha, Nguyen Thi Thu; Goh, Bee-Min; Saunders, Martin; Jiang, Zhong-Tao; Altarawneh, Mohammednoor; Dlugogorski, Bogdan Z; El-Harbawi, Mohanad; Yin, Chun-Yang

    2017-06-07

    The prevalence of global arsenic groundwater contamination has driven widespread research on developing effective treatment systems including adsorption using various sorbents. The uptake of arsenic-based contaminants onto established sorbents such as activated carbon (AC) can be effectively enhanced via immobilization/impregnation of iron-based elements on the porous AC surface. Recent suggestions that AC pores structurally consist of an eclectic mix of curved fullerene-like sheets may affect the arsenic adsorption dynamics within the AC pores and is further complicated by the presence of nano-sized iron-based elements. We have therefore, attempted to shed light on the adsorptive interactions of arsenate-iron nanoparticles with curved fullerene-like sheets by using hybridized quantum mechanics/molecular mechanics (QMMM) calculations and microscopy characterization. It is found that, subsequent to optimization, chemisorption between HAsO 4 2- and the AC carbon sheet (endothermic process) is virtually non-existent - this observation is supported by experimental results. Conversely, the incorporation of iron nanoparticles (FeNPs) into the AC carbon sheet greatly facilitates chemisorption of HAsO 4 2- . Our calculation implies that iron carbide is formed at the junction between the iron and the AC interface and this tightly chemosorbed layer prevents detachment of the FeNPs on the AC surface. Other aspects including electronic structure/properties, carbon arrangement defects and rate of adsorptive interaction, which are determined using the Climbing-Image NEB method, are also discussed.

  4. Exploring the 12-Key Approach: Perceptions and Experiences of Improvising Jazz Vocalists

    Science.gov (United States)

    Hargreaves, Wendy

    2016-01-01

    The 12-key approach is considered a foundational practice strategy for jazz instrumentalists. Its relevance to vocalists, however, seems less clear. This article investigates improvising jazz vocalists' perceptions and experiences of using the 12-key approach as distinguished from instrumentalists'. It uses data from a two-phase, mixed methods…

  5. A Novel Approach to London: Infusing Ethnography and the Study Abroad Experience

    Science.gov (United States)

    Schaefer, Zachary A.; Lynch, Owen H.

    2017-01-01

    Courses: Qualitative Research Methods, Ethnographic Research Methods. Objective: This purpose of this activity is to document the enculturation process through which students begin to understand a new culture during a study abroad experience. To accomplish this, we created a new pedagogical approach for study abroad experiences that involved a…

  6. Innovative Approach to the Organization of Future Social Workers' Practical Training: Foreign Experience

    Science.gov (United States)

    Polishchuk, Vira; Slozanska, Hanna

    2014-01-01

    Innovative approaches to practical training of future social workers in higher educational establishments have been defined. Peculiarities of foreign experience of social workers' practical training in higher educational establishments have been analyzed. Experience of organizing practice for bachelor students studying at "Social Work"…

  7. Principal Curves on Riemannian Manifolds.

    Science.gov (United States)

    Hauberg, Soren

    2016-09-01

    Euclidean statistics are often generalized to Riemannian manifolds by replacing straight-line interpolations with geodesic ones. While these Riemannian models are familiar-looking, they are restricted by the inflexibility of geodesics, and they rely on constructions which are optimal only in Euclidean domains. We consider extensions of Principal Component Analysis (PCA) to Riemannian manifolds. Classic Riemannian approaches seek a geodesic curve passing through the mean that optimizes a criteria of interest. The requirements that the solution both is geodesic and must pass through the mean tend to imply that the methods only work well when the manifold is mostly flat within the support of the generating distribution. We argue that instead of generalizing linear Euclidean models, it is more fruitful to generalize non-linear Euclidean models. Specifically, we extend the classic Principal Curves from Hastie & Stuetzle to data residing on a complete Riemannian manifold. We show that for elliptical distributions in the tangent of spaces of constant curvature, the standard principal geodesic is a principal curve. The proposed model is simple to compute and avoids many of the pitfalls of traditional geodesic approaches. We empirically demonstrate the effectiveness of the Riemannian principal curves on several manifolds and datasets.

  8. JUMPING THE CURVE

    Directory of Open Access Journals (Sweden)

    René Pellissier

    2012-01-01

    Full Text Available This paper explores the notion ofjump ing the curve,following from Handy 's S-curve onto a new curve with new rules policies and procedures. . It claims that the curve does not generally lie in wait but has to be invented by leadership. The focus of this paper is the identification (mathematically and inferentially ofthat point in time, known as the cusp in catastrophe theory, when it is time to change - pro-actively, pre-actively or reactively. These three scenarios are addressed separately and discussed in terms ofthe relevance ofeach.

  9. A Bayesian hierarchical model for demand curve analysis.

    Science.gov (United States)

    Ho, Yen-Yi; Nhu Vo, Tien; Chu, Haitao; Luo, Xianghua; Le, Chap T

    2018-07-01

    Drug self-administration experiments are a frequently used approach to assessing the abuse liability and reinforcing property of a compound. It has been used to assess the abuse liabilities of various substances such as psychomotor stimulants and hallucinogens, food, nicotine, and alcohol. The demand curve generated from a self-administration study describes how demand of a drug or non-drug reinforcer varies as a function of price. With the approval of the 2009 Family Smoking Prevention and Tobacco Control Act, demand curve analysis provides crucial evidence to inform the US Food and Drug Administration's policy on tobacco regulation, because it produces several important quantitative measurements to assess the reinforcing strength of nicotine. The conventional approach popularly used to analyze the demand curve data is individual-specific non-linear least square regression. The non-linear least square approach sets out to minimize the residual sum of squares for each subject in the dataset; however, this one-subject-at-a-time approach does not allow for the estimation of between- and within-subject variability in a unified model framework. In this paper, we review the existing approaches to analyze the demand curve data, non-linear least square regression, and the mixed effects regression and propose a new Bayesian hierarchical model. We conduct simulation analyses to compare the performance of these three approaches and illustrate the proposed approaches in a case study of nicotine self-administration in rats. We present simulation results and discuss the benefits of using the proposed approaches.

  10. Learning curves in energy planning models

    Energy Technology Data Exchange (ETDEWEB)

    Barreto, L; Kypreos, S [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    This study describes the endogenous representation of investment cost learning curves into the MARKAL energy planning model. A piece-wise representation of the learning curves is implemented using Mixed Integer Programming. The approach is briefly described and some results are presented. (author) 3 figs., 5 refs.

  11. A minicourse on moduli of curves

    International Nuclear Information System (INIS)

    Looijenga, E.

    2000-01-01

    These are notes that accompany a short course given at the School on Algebraic Geometry 1999 at the ICTP, Trieste. A major goal is to outline various approaches to moduli spaces of curves. In the last part I discuss the algebraic classes that naturally live on these spaces; these can be thought of as the characteristic classes for bundles of curves. (author)

  12. Symmetry Properties of Potentiometric Titration Curves.

    Science.gov (United States)

    Macca, Carlo; Bombi, G. Giorgio

    1983-01-01

    Demonstrates how the symmetry properties of titration curves can be efficiently and rigorously treated by means of a simple method, assisted by the use of logarithmic diagrams. Discusses the symmetry properties of several typical titration curves, comparing the graphical approach and an explicit mathematical treatment. (Author/JM)

  13. Deep-learnt classification of light curves

    DEFF Research Database (Denmark)

    Mahabal, Ashish; Gieseke, Fabian; Pai, Akshay Sadananda Uppinakudru

    2017-01-01

    Astronomy light curves are sparse, gappy, and heteroscedastic. As a result standard time series methods regularly used for financial and similar datasets are of little help and astronomers are usually left to their own instruments and techniques to classify light curves. A common approach is to d...

  14. Simulation of IRIS 2010 missile experiments for validation of integral simulation approach

    International Nuclear Information System (INIS)

    Siefert, Alexander; Henkel, Fritz-Otto

    2013-01-01

    Conclusion: Used material model and model approach shows acceptable results in comparison with test data, but further improvements are possible. Tri-axial Test: The material model must be improved to capture the higher strain values for test with confining pressure. Possible solution: Defining separate damage curves for different confining pressures. Flexural Test: Model approach has to be approved regarding the swing back phase. Possible first step: Investigation of crack closing –tensional recovery. Punching Test: Challenge for this simulation is the element erosions. Solution: Defining a reliable deletion criteria is possible by averaging several case studies. Alternative is the application of SPH-method. In General: Material properties showed differences to code definitions. Therefore a required input for detailed analysis of local damage are test data (especially for existing structures). Microscopic cracking can’t be investigated using a homogenous material

  15. Can a teaching assistant experience in a surgical anatomy course influence the learning curve for nontechnical skill development for surgical residents?

    Science.gov (United States)

    Heidenreich, Mark J; Musonza, Tashinga; Pawlina, Wojciech; Lachman, Nirusha

    2016-01-01

    The foundation upon which surgical residents are trained to work comprises more than just critical cognitive, clinical, and technical skill. In an environment where the synchronous application of expertise is vital to patient outcomes, the expectation for optimal functioning within a multidisciplinary team is extremely high. Studies have shown that for most residents, one of the most difficult milestones in the path to achieving professional expertise in a surgical career is overcoming the learning curve. This view point commentary provides a reflection from the two senior medical students who have participated in the Student-as-Teacher program developed by the Department of Anatomy at Mayo Clinic, designed to prepare students for their teaching assistant (TA) role in anatomy courses. Both students participated as TAs in a six week surgical anatomy course for surgical first assistant students offered by the School of Health Sciences at Mayo Clinic. Development of teaching skills, nontechnical leadership, communication, and assessment skills, are discussed in relation to their benefits in preparing senior medical students for surgical residency. © 2015 American Association of Anatomists.

  16. Tornado-Shaped Curves

    Science.gov (United States)

    Martínez, Sol Sáez; de la Rosa, Félix Martínez; Rojas, Sergio

    2017-01-01

    In Advanced Calculus, our students wonder if it is possible to graphically represent a tornado by means of a three-dimensional curve. In this paper, we show it is possible by providing the parametric equations of such tornado-shaped curves.

  17. Simulating Supernova Light Curves

    International Nuclear Information System (INIS)

    Even, Wesley Paul; Dolence, Joshua C.

    2016-01-01

    This report discusses supernova light simulations. A brief review of supernovae, basics of supernova light curves, simulation tools used at LANL, and supernova results are included. Further, it happens that many of the same methods used to generate simulated supernova light curves can also be used to model the emission from fireballs generated by explosions in the earth's atmosphere.

  18. Simulating Supernova Light Curves

    Energy Technology Data Exchange (ETDEWEB)

    Even, Wesley Paul [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dolence, Joshua C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-05-05

    This report discusses supernova light simulations. A brief review of supernovae, basics of supernova light curves, simulation tools used at LANL, and supernova results are included. Further, it happens that many of the same methods used to generate simulated supernova light curves can also be used to model the emission from fireballs generated by explosions in the earth’s atmosphere.

  19. Image scaling curve generation

    NARCIS (Netherlands)

    2012-01-01

    The present invention relates to a method of generating an image scaling curve, where local saliency is detected in a received image. The detected local saliency is then accumulated in the first direction. A final scaling curve is derived from the detected local saliency and the image is then

  20. Image scaling curve generation.

    NARCIS (Netherlands)

    2011-01-01

    The present invention relates to a method of generating an image scaling curve, where local saliency is detected in a received image. The detected local saliency is then accumulated in the first direction. A final scaling curve is derived from the detected local saliency and the image is then

  1. Tempo curves considered harmful

    NARCIS (Netherlands)

    Desain, P.; Honing, H.

    1993-01-01

    In the literature of musicology, computer music research and the psychology of music, timing or tempo measurements are mostly presented in the form of continuous curves. The notion of these tempo curves is dangerous, despite its widespread use, because it lulls its users into the false impression

  2. The Roles of Macrobenthic Mollusks as Bioindicator in Response to Environmental Disturbance : Cumulative k-dominance curves and bubble plots ordination approaches

    Science.gov (United States)

    Putro, Sapto P.; Muhammad, Fuad; Aininnur, Amalia; Widowati; Suhartana

    2017-02-01

    Floating net cage is one of the aquaculture practice operated in Indonesian coastal areas that has been growing rapidly over the last two decades. This study is aimed to assess the roles of macrobenthic mollusks as bioindicator in response to environmental disturbance caused by fish farming activities, and compare the samples within the locations using graphical methods. The research was done at the floating net cage fish farming area in the Awerange Gulf, South Sulawesi, Indonesia at the coordinates between 79°0500‧- 79°1500‧ LS and 953°1500‧- 953°2000‧ BT, at the polyculture and reference areas, which was located 1 km away from farming area. Sampling period was conducted between October 2014 to June 2015. The sediment samples were taken from the two locations with two sampling time and three replicates using Van Veen Grab for biotic and abiotic assessment. Mollusks as biotic parameter were fixed using 4% formalin solution and were preserved using 70% ethanol solution after 1mm mesh size. The macrobenthic mollusks were found as many as 15 species consisting of 14 families and 2 classes (gastropods and bivalves). Based on cumulative k-dominance analysis projected on each station, the line of station K3T1 (reference area; first sampling time) and KJAB P3T2 (polyculture area; second sampling time) are located below others curves, indicating the highest evenness and diversity compared to the other stations, whereas station K2T1 (reference area; first sampling time) and K3T2 (polyculture area, second sampling time) are located on the top, indicate the lowest value of evenness and diversity. Based on the bubble plots NMDS ordination, the four dominant taxa/species did not clearly show involvement in driving/shifting the ordinate position of station on the graph, except T. agilis. However, the two species showed involvement in driving/shifting the ordinate position of two stations of the reference areas from the first sampling time by Rynoclavis sordidula

  3. The curve shortening problem

    CERN Document Server

    Chou, Kai-Seng

    2001-01-01

    Although research in curve shortening flow has been very active for nearly 20 years, the results of those efforts have remained scattered throughout the literature. For the first time, The Curve Shortening Problem collects and illuminates those results in a comprehensive, rigorous, and self-contained account of the fundamental results.The authors present a complete treatment of the Gage-Hamilton theorem, a clear, detailed exposition of Grayson''s convexity theorem, a systematic discussion of invariant solutions, applications to the existence of simple closed geodesics on a surface, and a new, almost convexity theorem for the generalized curve shortening problem.Many questions regarding curve shortening remain outstanding. With its careful exposition and complete guide to the literature, The Curve Shortening Problem provides not only an outstanding starting point for graduate students and new investigations, but a superb reference that presents intriguing new results for those already active in the field.

  4. Healthcare students' experiences when integrating e-learning and flipped classroom instructional approaches.

    Science.gov (United States)

    Telford, Mark; Senior, Emma

    2017-06-08

    This article describes the experiences of undergraduate healthcare students taking a module adopting a 'flipped classroom' approach. Evidence suggests that flipped classroom as a pedagogical tool has the potential to enhance student learning and to improve healthcare practice. This innovative approach was implemented within a healthcare curriculum and in a module looking at public health delivered at the beginning of year two of a 3-year programme. The focus of the evaluation study was on the e-learning resources used in the module and the student experiences of these; with a specific aim to evaluate this element of the flipped classroom approach. A mixed-methods approach was adopted and data collected using questionnaires, which were distributed across a whole cohort, and a focus group involving ten participants. Statistical analysis of the data showed the positive student experience of engaging with e-learning. The thematic analysis identified two key themes; factors influencing a positive learning experience and the challenges when developing e-learning within a flipped classroom approach. The study provides guidance for further developments and improvements when developing e-learning as part of the flipped classroom approach.

  5. MICA: Multiple interval-based curve alignment

    Science.gov (United States)

    Mann, Martin; Kahle, Hans-Peter; Beck, Matthias; Bender, Bela Johannes; Spiecker, Heinrich; Backofen, Rolf

    2018-01-01

    MICA enables the automatic synchronization of discrete data curves. To this end, characteristic points of the curves' shapes are identified. These landmarks are used within a heuristic curve registration approach to align profile pairs by mapping similar characteristics onto each other. In combination with a progressive alignment scheme, this enables the computation of multiple curve alignments. Multiple curve alignments are needed to derive meaningful representative consensus data of measured time or data series. MICA was already successfully applied to generate representative profiles of tree growth data based on intra-annual wood density profiles or cell formation data. The MICA package provides a command-line and graphical user interface. The R interface enables the direct embedding of multiple curve alignment computation into larger analyses pipelines. Source code, binaries and documentation are freely available at https://github.com/BackofenLab/MICA

  6. Inverse Diffusion Curves Using Shape Optimization.

    Science.gov (United States)

    Zhao, Shuang; Durand, Fredo; Zheng, Changxi

    2018-07-01

    The inverse diffusion curve problem focuses on automatic creation of diffusion curve images that resemble user provided color fields. This problem is challenging since the 1D curves have a nonlinear and global impact on resulting color fields via a partial differential equation (PDE). We introduce a new approach complementary to previous methods by optimizing curve geometry. In particular, we propose a novel iterative algorithm based on the theory of shape derivatives. The resulting diffusion curves are clean and well-shaped, and the final image closely approximates the input. Our method provides a user-controlled parameter to regularize curve complexity, and generalizes to handle input color fields represented in a variety of formats.

  7. Consistent Valuation across Curves Using Pricing Kernels

    Directory of Open Access Journals (Sweden)

    Andrea Macrina

    2018-03-01

    Full Text Available The general problem of asset pricing when the discount rate differs from the rate at which an asset’s cash flows accrue is considered. A pricing kernel framework is used to model an economy that is segmented into distinct markets, each identified by a yield curve having its own market, credit and liquidity risk characteristics. The proposed framework precludes arbitrage within each market, while the definition of a curve-conversion factor process links all markets in a consistent arbitrage-free manner. A pricing formula is then derived, referred to as the across-curve pricing formula, which enables consistent valuation and hedging of financial instruments across curves (and markets. As a natural application, a consistent multi-curve framework is formulated for emerging and developed inter-bank swap markets, which highlights an important dual feature of the curve-conversion factor process. Given this multi-curve framework, existing multi-curve approaches based on HJM and rational pricing kernel models are recovered, reviewed and generalised and single-curve models extended. In another application, inflation-linked, currency-based and fixed-income hybrid securities are shown to be consistently valued using the across-curve valuation method.

  8. Learning Curve? Which One?

    Directory of Open Access Journals (Sweden)

    Paulo Prochno

    2004-07-01

    Full Text Available Learning curves have been studied for a long time. These studies provided strong support to the hypothesis that, as organizations produce more of a product, unit costs of production decrease at a decreasing rate (see Argote, 1999 for a comprehensive review of learning curve studies. But the organizational mechanisms that lead to these results are still underexplored. We know some drivers of learning curves (ADLER; CLARK, 1991; LAPRE et al., 2000, but we still lack a more detailed view of the organizational processes behind those curves. Through an ethnographic study, I bring a comprehensive account of the first year of operations of a new automotive plant, describing what was taking place on in the assembly area during the most relevant shifts of the learning curve. The emphasis is then on how learning occurs in that setting. My analysis suggests that the overall learning curve is in fact the result of an integration process that puts together several individual ongoing learning curves in different areas throughout the organization. In the end, I propose a model to understand the evolution of these learning processes and their supporting organizational mechanisms.

  9. A statistical approach to evaluate the performance of cardiac biomarkers in predicting death due to acute myocardial infarction: time-dependent ROC curve

    Science.gov (United States)

    Karaismailoğlu, Eda; Dikmen, Zeliha Günnur; Akbıyık, Filiz; Karaağaoğlu, Ahmet Ergun

    2018-04-30

    Background/aim: Myoglobin, cardiac troponin T, B-type natriuretic peptide (BNP), and creatine kinase isoenzyme MB (CK-MB) are frequently used biomarkers for evaluating risk of patients admitted to an emergency department with chest pain. Recently, time- dependent receiver operating characteristic (ROC) analysis has been used to evaluate the predictive power of biomarkers where disease status can change over time. We aimed to determine the best set of biomarkers that estimate cardiac death during follow-up time. We also obtained optimal cut-off values of these biomarkers, which differentiates between patients with and without risk of death. A web tool was developed to estimate time intervals in risk. Materials and methods: A total of 410 patients admitted to the emergency department with chest pain and shortness of breath were included. Cox regression analysis was used to determine an optimal set of biomarkers that can be used for estimating cardiac death and to combine the significant biomarkers. Time-dependent ROC analysis was performed for evaluating performances of significant biomarkers and a combined biomarker during 240 h. The bootstrap method was used to compare statistical significance and the Youden index was used to determine optimal cut-off values. Results : Myoglobin and BNP were significant by multivariate Cox regression analysis. Areas under the time-dependent ROC curves of myoglobin and BNP were about 0.80 during 240 h, and that of the combined biomarker (myoglobin + BNP) increased to 0.90 during the first 180 h. Conclusion: Although myoglobin is not clinically specific to a cardiac event, in our study both myoglobin and BNP were found to be statistically significant for estimating cardiac death. Using this combined biomarker may increase the power of prediction. Our web tool can be useful for evaluating the risk status of new patients and helping clinicians in making decisions.

  10. Longitudinal associations between body mass index, physical activity, and healthy dietary behaviors in adults: A parallel latent growth curve modeling approach.

    Directory of Open Access Journals (Sweden)

    Youngdeok Kim

    Full Text Available Physical activity (PA and healthy dietary behaviors (HDB are two well-documented lifestyle factors influencing body mass index (BMI. This study examined 7-year longitudinal associations between changes in PA, HDB, and BMI among adults using a parallel latent growth curve modeling (LGCM.We used prospective cohort data collected by a private company (SimplyWell LLC, Omaha, NE, USA implementing a workplace health screening program. Data from a total of 2,579 adults who provided valid BMI, PA, and HDB information for at least 5 out of 7 follow-up years from the time they entered the program were analyzed. PA and HDB were subjectively measured during an annual online health survey. Height and weight measured during an annual onsite health screening were used to calculate BMI (kg·m2. The parallel LGCMs stratified by gender and baseline weight status (normal: BMI30 were fitted to examine the longitudinal associations of changes in PA and HDB with change in BMI over years.On average, BMI gradually increased over years, at rates ranging from 0.06 to 0.20 kg·m2·year, with larger increases observed among those of normal baseline weight status across genders. The increases in PA and HDB were independently associated with a smaller increase in BMI for obese males (b = -1.70 and -1.98, respectively, and overweight females (b = -1.85 and -2.46, respectively and obese females (b = -2.78 and -3.08, respectively. However, no significant associations of baseline PA and HDB with changes in BMI were observed.Our study suggests that gradual increases in PA and HDB are independently associated with smaller increases in BMI in overweight and obese adults, but not in normal weight individuals. Further study is warranted to address factors that check increases in BMI in normal weight adults.

  11. Climatic and basin factors affecting the flood frequency curve: PART II – A full sensitivity analysis based on the continuous simulation approach combined with a factorial experimental design

    Directory of Open Access Journals (Sweden)

    M. Franchini

    2000-01-01

    Full Text Available The sensitivity analysis described in Hashemi et al. (2000 is based on one-at-a-time perturbations to the model parameters. This type of analysis cannot highlight the presence of parameter interactions which might indeed affect the characteristics of the flood frequency curve (ffc even more than the individual parameters. For this reason, the effects of the parameters of the rainfall, rainfall runoff models and of the potential evapotranspiration demand on the ffc are investigated here through an analysis of the results obtained from a factorial experimental design, where all the parameters are allowed to vary simultaneously. This latter, more complex, analysis confirms the results obtained in Hashemi et al. (2000 thus making the conclusions drawn there of wider validity and not related strictly to the reference set selected. However, it is shown that two-factor interactions are present not only between different pairs of parameters of an individual model, but also between pairs of parameters of different models, such as rainfall and rainfall-runoff models, thus demonstrating the complex interaction between climate and basin characteristics affecting the ffc and in particular its curvature. Furthermore, the wider range of climatic regime behaviour produced within the factorial experimental design shows that the probability distribution of soil moisture content at the storm arrival time is no longer sufficient to explain the link between the perturbations to the parameters and their effects on the ffc, as was suggested in Hashemi et al. (2000. Other factors have to be considered, such as the probability distribution of the soil moisture capacity, and the rainfall regime, expressed through the annual maximum rainfalls over different durations. Keywords: Monte Carlo simulation; factorial experimental design; analysis of variance (ANOVA

  12. Validity limits in J-resistance curve determination: A computational approach to ductile crack growth under large-scale yielding conditions. Volume 2

    International Nuclear Information System (INIS)

    Shih, C.F.; Xia, L.; Hutchinson, J.W.

    1995-02-01

    In this report, Volume 2, Mode I crack initiation and growth under plane strain conditions in tough metals are computed using an elastic/plastic continuum model which accounts for void growth and coalescence ahead of the crack tip. The material parameters include the stress-strain properties, along with the parameters characterizing the spacing and volume fraction of voids in material elements lying in the plane of the crack. For a given set of these parameters and a specific specimen, or component, subject to a specific loading, relationships among load, load-line displacement and crack advance can be computed with no restrictions on the extent of plastic deformation. Similarly, there is no limit on crack advance, except that it must take place on the symmetry plane ahead of the initial crack. Suitably defined measures of crack tip loading intensity, such as those based on the J-integral, can also be computed, thereby directly generating crack growth resistance curves. In this report, the model is applied to five specimen geometries which are known to give rise to significantly different crack tip constraints and crack growth resistance behaviors. Computed results are compared with sets of experimental data for two tough steels for four of the specimen types. Details of the load, displacement and crack growth histories are accurately reproduced, even when extensive crack growth takes place under conditions of fully plastic yielding. A description of material resistance to crack initiation and subsequent growth is essential for assessing structural integrity such as nuclear pressure vessels and piping

  13. Experience Transfer in Norwegian Oil and Gas Industry: Approaches and Organizational Mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Aase, Karina

    1997-07-01

    The core aim of the study is to explore the concept of experience transfer in oil and gas industry, and how an oil company approaches this concept. The thesis consists of five papers which are combined in a general description entitled 'Experience transfer in Norwegian oil and gas industry: approaches and organizational mechanisms'. The first paper describes how organizational members perceive experience transfer, and then specifies the many organizational and structural barriers that have to be overcome to achieve efficient experience transfer. The second paper elaborates and assesses the organizational means an oil company implements to address experience transfer. The third paper describes a process of improving and using requirement and procedure handbooks for experience transfer. The fourth paper explores in more detail how the use of information technology influences experience transfer. And the fifth paper compares organizational members' perceptions of experience transfer means in an oil company and an engineering company involved in offshore development projects. Some of the papers are based upon the same data material. Therefore there are reiterations in parts of the contents, especially in the methodological sections.

  14. Experience Transfer in Norwegian Oil and Gas Industry: Approaches and Organizational Mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Aase, Karina

    1997-07-01

    The core aim of the study is to explore the concept of experience transfer in oil and gas industry, and how an oil company approaches this concept. The thesis consists of five papers which are combined in a general description entitled 'Experience transfer in Norwegian oil and gas industry: approaches and organizational mechanisms'. The first paper describes how organizational members perceive experience transfer, and then specifies the many organizational and structural barriers that have to be overcome to achieve efficient experience transfer. The second paper elaborates and assesses the organizational means an oil company implements to address experience transfer. The third paper describes a process of improving and using requirement and procedure handbooks for experience transfer. The fourth paper explores in more detail how the use of information technology influences experience transfer. And the fifth paper compares organizational members' perceptions of experience transfer means in an oil company and an engineering company involved in offshore development projects. Some of the papers are based upon the same data material. Therefore there are reiterations in parts of the contents, especially in the methodological sections.

  15. Experience Transfer in Norwegian Oil and Gas Industry: Approaches and Organizational Mechanisms

    International Nuclear Information System (INIS)

    Aase, Karina

    1997-01-01

    The core aim of the study is to explore the concept of experience transfer in oil and gas industry, and how an oil company approaches this concept. The thesis consists of five papers which are combined in a general description entitled 'Experience transfer in Norwegian oil and gas industry: approaches and organizational mechanisms'. The first paper describes how organizational members perceive experience transfer, and then specifies the many organizational and structural barriers that have to be overcome to achieve efficient experience transfer. The second paper elaborates and assesses the organizational means an oil company implements to address experience transfer. The third paper describes a process of improving and using requirement and procedure handbooks for experience transfer. The fourth paper explores in more detail how the use of information technology influences experience transfer. And the fifth paper compares organizational members' perceptions of experience transfer means in an oil company and an engineering company involved in offshore development projects. Some of the papers are based upon the same data material. Therefore there are reiterations in parts of the contents, especially in the methodological sections

  16. Experience with the Notch Stress Approach for Fatigue Assessment of Welded Joints

    DEFF Research Database (Denmark)

    Pedersen, Mikkel Melters; Mouritsen, Ole Ø.; Hansen, Michael Rygaard

    2010-01-01

    In this paper, fatigue assessment using the notch stress approach is discussed based on re-analysis of many fatigue test results and experience from practical application. Three topics are treated; evaluation of the fatigue strength for as-welded details (FAT225) in the notch stress system......, problems regarding assessment of mild-SCF details and a novel proposal for extension of the notch stress approach for use with post-weld treated details....

  17. The crime kuznets curve

    OpenAIRE

    Buonanno, Paolo; Fergusson, Leopoldo; Vargas, Juan Fernando

    2014-01-01

    We document the existence of a Crime Kuznets Curve in US states since the 1970s. As income levels have risen, crime has followed an inverted U-shaped pattern, first increasing and then dropping. The Crime Kuznets Curve is not explained by income inequality. In fact, we show that during the sample period inequality has risen monotonically with income, ruling out the traditional Kuznets Curve. Our finding is robust to adding a large set of controls that are used in the literature to explain the...

  18. Comparison of Predictive Factors for Postoperative Incontinence of Holmium Laser Enucleation of the Prostate by the Surgeons' Experience During Learning Curve.

    Science.gov (United States)

    Shigemura, Katsumi; Tanaka, Kazushi; Yamamichi, Fukashi; Chiba, Koji; Fujisawa, Masato

    2016-03-01

    To detect predictive factors for postoperative incontinence following holmium laser enucleation of the prostate (HoLEP) according to surgeon experience (beginner or experienced) and preoperative clinical data. Of 224 patients, a total of 203 with available data on incontinence were investigated. The potential predictive factors for post-HoLEP incontinence included clinical factors, such as patient age, and preoperative urodynamic study results, including detrusor overactivity (DO). We also classified the surgeons performing the procedure according to their HoLEP experience: beginner (predictive factor at the super-short period (the next day of catheter removal: odds ratio [OR], 3.375; P=0.000). Additionally, patient age, surgeon mentorship (inverse correlation), and prostate volume were significant predictive factors at the 1-month interval after HoLEP (OR, 1.072; P=0.004; OR, 0.251; P=0.002; and OR, 1.008; P=0.049, respectively). With regards to surgeon experience, DO and preoperative International Prostate Symptom Score (inverse) at the super-short period, and patient age and mentorship (inverse correlation) at the 1-month interval after HoLEP (OR, 3.952; P=0.002; OR, 1.084; P=0.015; and OR,1.084; P=0.015; OR, 0.358; P=0.003, respectively) were significant predictive factors for beginners, and first desire to void (FDV) at 1 month after HoLEP (OR, 1.009; P=0.012) was a significant predictive factor for experienced surgeons in multivariate analysis. Preoperative DO, IPSS, patient age, and surgeon mentorship were significant predictive factors of postoperative patient incontinence for beginner surgeons, while FDV was a significant predictive factors for experienced surgeons. These findings should be taken into account by surgeons performing HoLEP to maximize the patient's quality of life with regards to urinary continence.

  19. Bond yield curve construction

    Directory of Open Access Journals (Sweden)

    Kožul Nataša

    2014-01-01

    Full Text Available In the broadest sense, yield curve indicates the market's view of the evolution of interest rates over time. However, given that cost of borrowing it closely linked to creditworthiness (ability to repay, different yield curves will apply to different currencies, market sectors, or even individual issuers. As government borrowing is indicative of interest rate levels available to other market players in a particular country, and considering that bond issuance still remains the dominant form of sovereign debt, this paper describes yield curve construction using bonds. The relationship between zero-coupon yield, par yield and yield to maturity is given and their usage in determining curve discount factors is described. Their usage in deriving forward rates and pricing related derivative instruments is also discussed.

  20. SRHA calibration curve

    Data.gov (United States)

    U.S. Environmental Protection Agency — an UV calibration curve for SRHA quantitation. This dataset is associated with the following publication: Chang, X., and D. Bouchard. Surfactant-Wrapped Multiwalled...

  1. Bragg Curve Spectroscopy

    International Nuclear Information System (INIS)

    Gruhn, C.R.

    1981-05-01

    An alternative utilization is presented for the gaseous ionization chamber in the detection of energetic heavy ions, which is called Bragg Curve Spectroscopy (BCS). Conceptually, BCS involves using the maximum data available from the Bragg curve of the stopping heavy ion (HI) for purposes of identifying the particle and measuring its energy. A detector has been designed that measures the Bragg curve with high precision. From the Bragg curve the range from the length of the track, the total energy from the integral of the specific ionization over the track, the dE/dx from the specific ionization at the beginning of the track, and the Bragg peak from the maximum of the specific ionization of the HI are determined. This last signal measures the atomic number, Z, of the HI unambiguously

  2. Developing students’ ideas about lens imaging: teaching experiments with an image-based approach

    Science.gov (United States)

    Grusche, Sascha

    2017-07-01

    Lens imaging is a classic topic in physics education. To guide students from their holistic viewpoint to the scientists’ analytic viewpoint, an image-based approach to lens imaging has recently been proposed. To study the effect of the image-based approach on undergraduate students’ ideas, teaching experiments are performed and evaluated using qualitative content analysis. Some of the students’ ideas have not been reported before, namely those related to blurry lens images, and those developed by the proposed teaching approach. To describe learning pathways systematically, a conception-versus-time coordinate system is introduced, specifying how teaching actions help students advance toward a scientific understanding.

  3. A Simulation Modeling Approach Method Focused on the Refrigerated Warehouses Using Design of Experiment

    Science.gov (United States)

    Cho, G. S.

    2017-09-01

    For performance optimization of Refrigerated Warehouses, design parameters are selected based on the physical parameters such as number of equipment and aisles, speeds of forklift for ease of modification. This paper provides a comprehensive framework approach for the system design of Refrigerated Warehouses. We propose a modeling approach which aims at the simulation optimization so as to meet required design specifications using the Design of Experiment (DOE) and analyze a simulation model using integrated aspect-oriented modeling approach (i-AOMA). As a result, this suggested method can evaluate the performance of a variety of Refrigerated Warehouses operations.

  4. Power Curve Measurements FGW

    DEFF Research Database (Denmark)

    Georgieva Yankova, Ginka; Federici, Paolo

    This report describes power curve measurements carried out on a given turbine in a chosen period. The measurements are carried out in accordance to IEC 61400-12-1 Ed. 1 and FGW Teil 2.......This report describes power curve measurements carried out on a given turbine in a chosen period. The measurements are carried out in accordance to IEC 61400-12-1 Ed. 1 and FGW Teil 2....

  5. Curves and Abelian varieties

    CERN Document Server

    Alexeev, Valery; Clemens, C Herbert; Beauville, Arnaud

    2008-01-01

    This book is devoted to recent progress in the study of curves and abelian varieties. It discusses both classical aspects of this deep and beautiful subject as well as two important new developments, tropical geometry and the theory of log schemes. In addition to original research articles, this book contains three surveys devoted to singularities of theta divisors, of compactified Jacobians of singular curves, and of "strange duality" among moduli spaces of vector bundles on algebraic varieties.

  6. Comparison of Predictive Factors for Postoperative Incontinence of Holmium Laser Enucleation of the Prostate by the Surgeons’ Experience During Learning Curve

    Directory of Open Access Journals (Sweden)

    Katsumi Shigemura

    2016-03-01

    Full Text Available Purpose: To detect predictive factors for postoperative incontinence following holmium laser enucleation of the prostate (HoLEP according to surgeon experience (beginner or experienced and preoperative clinical data. Methods: Of 224 patients, a total of 203 with available data on incontinence were investigated. The potential predictive factors for post-HoLEP incontinence included clinical factors, such as patient age, and preoperative urodynamic study results, including detrusor overactivity (DO. We also classified the surgeons performing the procedure according to their HoLEP experience: beginner (<21 cases and experienced (≥21 cases. Results: Our statistical data showed DO was a significant predictive factor at the super-short period (the next day of catheter removal: odds ratio [OR], 3.375; P=0.000. Additionally, patient age, surgeon mentorship (inverse correlation, and prostate volume were significant predictive factors at the 1-month interval after HoLEP (OR, 1.072; P=0.004; OR, 0.251; P=0.002; and OR, 1.008; P=0.049, respectively. With regards to surgeon experience, DO and preoperative International Prostate Symptom Score (inverse at the super-short period, and patient age and mentorship (inverse correlation at the 1-month interval after HoLEP (OR, 3.952; P=0.002; OR, 1.084; P=0.015; and OR,1.084; P=0.015; OR, 0.358; P=0.003, respectively were significant predictive factors for beginners, and first desire to void (FDV at 1 month after HoLEP (OR, 1.009; P=0.012 was a significant predictive factor for experienced surgeons in multivariate analysis. Conclusions: Preoperative DO, IPSS, patient age, and surgeon mentorship were significant predictive factors of postoperative patient incontinence for beginner surgeons, while FDV was a significant predictive factors for experienced surgeons. These findings should be taken into account by surgeons performing HoLEP to maximize the patient’s quality of life with regards to urinary continence.

  7. Fermions in curved spacetimes

    Energy Technology Data Exchange (ETDEWEB)

    Lippoldt, Stefan

    2016-01-21

    In this thesis we study a formulation of Dirac fermions in curved spacetime that respects general coordinate invariance as well as invariance under local spin base transformations. We emphasize the advantages of the spin base invariant formalism both from a conceptual as well as from a practical viewpoint. This suggests that local spin base invariance should be added to the list of (effective) properties of (quantum) gravity theories. We find support for this viewpoint by the explicit construction of a global realization of the Clifford algebra on a 2-sphere which is impossible in the spin-base non-invariant vielbein formalism. The natural variables for this formulation are spacetime-dependent Dirac matrices subject to the Clifford-algebra constraint. In particular, a coframe, i.e. vielbein field is not required. We disclose the hidden spin base invariance of the vielbein formalism. Explicit formulas for the spin connection as a function of the Dirac matrices are found. This connection consists of a canonical part that is completely fixed in terms of the Dirac matrices and a free part that can be interpreted as spin torsion. The common Lorentz symmetric gauge for the vielbein is constructed for the Dirac matrices, even for metrics which are not linearly connected. Under certain criteria, it constitutes the simplest possible gauge, demonstrating why this gauge is so useful. Using the spin base formulation for building a field theory of quantized gravity and matter fields, we show that it suffices to quantize the metric and the matter fields. This observation is of particular relevance for field theory approaches to quantum gravity, as it can serve for a purely metric-based quantization scheme for gravity even in the presence of fermions. Hence, in the second part of this thesis we critically examine the gauge, and the field-parametrization dependence of renormalization group flows in the vicinity of non-Gaussian fixed points in quantum gravity. While physical

  8. Vital Orientation Feeling and Corporal Experiences in People with Eating Disorder: A Phenomenological and Narrative Approach

    Directory of Open Access Journals (Sweden)

    Duero, Dante Gabriel

    2012-12-01

    Full Text Available In this paper we analyze corporal experiences and the variations in existential feeling, in tree woman that have received mental disorder diagnosis. We have done in-depth interviews. We have used the constant comparison method to configure the categories and analysis. Then, we applied a phenomenological-narrative approach. Based on our results we evaluate and compared cases.

  9. University Teachers' Experiences of Academic Leadership and Their Approaches to Teaching

    Science.gov (United States)

    Ramsden, Paul; Prosser, Michael; Trigwell, Keith; Martin, Elaine

    2007-01-01

    The study examined associations between university teachers' experiences of academic leadership, their perceptions of a specific academic context and their approaches to teaching in a particular subject that was taught in that context. The sample consisted of 439 lecturers in Australian universities in four fields of study. Lecturers completed…

  10. Teaching Methods and Their Impact on Students' Emotions in Mathematics: An Experience-Sampling Approach

    Science.gov (United States)

    Bieg, Madeleine; Goetz, Thomas; Sticca, Fabio; Brunner, Esther; Becker, Eva; Morger, Vinzenz; Hubbard, Kyle

    2017-01-01

    Various theoretical approaches propose that emotions in the classroom are elicited by appraisal antecedents, with subjective experiences of control playing a crucial role in this context. Perceptions of control, in turn, are expected to be influenced by the classroom social environment, which can include the teaching methods being employed (e.g.,…

  11. The Impact of Years of Teaching Experience on the Classroom Management Approaches of Elementary School Teachers

    Science.gov (United States)

    Unal, Zafer; Unal, Aslihan

    2012-01-01

    This study provided a basis for answering the following essential question: Does the years of experience affect teachers' classroom management approaches? Data were collected from 268 primary school teachers. The findings of this study demonstrated that experienced teachers are more likely to prefer to be in control in their classrooms than…

  12. The Audio-Tutorial Approach to Learning Through Independent Study and Integrated Experiences.

    Science.gov (United States)

    Postlethwait, S. N.; And Others

    The rationale of the integrated experience approach to teaching botany at Purdue University is given and the history of the audio-tutorial course at Purdue and its present organization are described. A sample week's unit of study is given, including transcription of the tape, reproduction of printed materials and photographs of other materials…

  13. Quality Assurance and Its Impact from Higher Education Institutions' Perspectives: Methodological Approaches, Experiences and Expectations

    Science.gov (United States)

    Bejan, Stelian Andrei; Janatuinen, Tero; Jurvelin, Jouni; Klöpping, Susanne; Malinen, Heikki; Minke, Bernhard; Vacareanu, Radu

    2015-01-01

    This paper reports on methodological approaches, experiences and expectations referring to impact analysis of quality assurance from the perspective of three higher education institutions (students, teaching staff, quality managers) from Germany, Finland and Romania. The presentations of the three sample institutions focus on discussing the core…

  14. The Effect of Group Works and Demonstrative Experiments Based on Conceptual Change Approach: Photosynthesis and Respiration

    Science.gov (United States)

    Cibik, Ayse Sert; Diken, Emine Hatun; Darcin, Emine Selcen

    2008-01-01

    The purpose of this study is to investigate the effect of the use of group works and demonstration experiments based on conceptual change approach in the elimination of misconception about the subject of photosynthesis and respiration in plants in pre-service science teachers. This study was conducted with 78 pre-service science teachers including…

  15. College Student Environmental Activism: How Experiences and Identities Influence Environmental Activism Approaches

    Science.gov (United States)

    King, Laura A. H.

    2016-01-01

    College student environmental activism is one way students civically engage in addressing social issues. This study explores the environmental activism of twelve college students and how their experiences outside of college and in college influenced their activism. In addition, how students' identities influenced their approach to activism was…

  16. A New Approach toward Cyanotype Photography Using Tris-(Oxalato)ferrate(III): An Integrated Experiment

    Science.gov (United States)

    Fiorito, Pablo Alejandro; Polo, Andre´ Sarto

    2015-01-01

    This work presents an approach that integrates the preparation of a coordination compound, potassium tris- (oxalato)ferrate(III), with its photochemical behavior and provides a possible application, the printing of a photograph using the cyanotype technique. Through this experiment, students can be taught several concepts that occur in a…

  17. Evaluation of the learning curve for thulium laser enucleation of the prostate with the aid of a simulator tool but without tutoring: comparison of two surgeons with different levels of endoscopic experience.

    Science.gov (United States)

    Saredi, Giovanni; Pirola, Giacomo Maria; Pacchetti, Andrea; Lovisolo, Jon Alexander; Borroni, Giacomo; Sembenini, Federico; Marconi, Alberto Mario

    2015-06-09

    The aim of this study was to determine the learning curve for thulium laser enucleation of the prostate (ThuLEP) for two surgeons with different levels of urological endoscopic experience. From June 2012 to August 2013, ThuLEP was performed on 100 patients in our institution. We present the results of a prospective evaluation during which we analyzed data related to the learning curves for two surgeons of different levels of experience. The prostatic adenoma volumes ranged from 30 to 130 mL (average 61.2 mL). Surgeons A and B performed 48 and 52 operations, respectively. Six months after surgery, all patients were evaluated with the International Prostate Symptom Score questionnaire, uroflowmetry, and prostate-specific antigen test. Introduced in 2010, ThuLEP consists of blunt enucleation of the prostatic apex and lobes using the sheath of the resectoscope. This maneuver allows clearer visualization of the enucleation plane and precise identification of the prostatic capsule. These conditions permit total resection of the prostatic adenoma and coagulation of small penetrating vessels, thereby reducing the laser emission time. Most of the complications in this series were encountered during morcellation, which in some cases was performed under poor vision because of venous bleeding due to surgical perforation of the capsule during enucleation. Based on this analysis, we concluded that it is feasible for laser-naive urologists with endoscopic experience to learn to perform ThuLEP without tutoring. Those statements still require further validation in larger multicentric study cohort by several surgeon. The main novelty during the learning process was the use of a simulator that faithfully reproduced all of the surgical steps in prostates of various shapes and volumes.

  18. Understanding enhanced tourist experiences through technology: a brief approach to the Vilnius case

    Directory of Open Access Journals (Sweden)

    Ilona Beliatskaya

    2017-11-01

    Full Text Available The present research investigates the notion of enhanced tourist experiences through technology shedding light on co-creation practices and empowerment of customers. Neuhofer and Buhalis (2013 introduced a novel concept of technology-enhanced tourist experiences by generating a joint comprehension of new era of experiences which conjoin the elements of experiences, co-creation and technology. Being one of rather promoting cities in online environment Vilnius represents an interesting case of successive adoption of smart technologies in order to enhance tourist experiences and facilitate customer empowerment in Vilnius tourism domain. This study aims to determine technology-enhanced tourist experiences in order to measure factors of customer empowerment on the example of international incoming tourists to Vilnius (Lithuania. The mix-methods approach (qualitative online content and functionality analysis and quantitative survey was justified as being the most appropriate for the purpose of this research with intention to find a basis for applying of technology-enhanced tourist experiences in Vilnius tourism marketplace. The paper concludes with the definition of current level of ICTs application to enhance tourist experience co-creation and a discussion of practical implications of technology-enhanced tourist experiences development.

  19. A unified modeling approach for physical experiment design and optimization in laser driven inertial confinement fusion

    Energy Technology Data Exchange (ETDEWEB)

    Li, Haiyan [Mechatronics Engineering School of Guangdong University of Technology, Guangzhou 510006 (China); Huang, Yunbao, E-mail: Huangyblhy@gmail.com [Mechatronics Engineering School of Guangdong University of Technology, Guangzhou 510006 (China); Jiang, Shaoen, E-mail: Jiangshn@vip.sina.com [Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900 (China); Jing, Longfei, E-mail: scmyking_2008@163.com [Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900 (China); Tianxuan, Huang; Ding, Yongkun [Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900 (China)

    2015-11-15

    Highlights: • A unified modeling approach for physical experiment design is presented. • Any laser facility can be flexibly defined and included with two scripts. • Complex targets and laser beams can be parametrically modeled for optimization. • Automatically mapping of laser beam energy facilitates targets shape optimization. - Abstract: Physical experiment design and optimization is very essential for laser driven inertial confinement fusion due to the high cost of each shot. However, only limited experiments with simple structure or shape on several laser facilities can be designed and evaluated in available codes, and targets are usually defined by programming, which may lead to it difficult for complex shape target design and optimization on arbitrary laser facilities. A unified modeling approach for physical experiment design and optimization on any laser facilities is presented in this paper. Its core idea includes: (1) any laser facility can be flexibly defined and included with two scripts, (2) complex shape targets and laser beams can be parametrically modeled based on features, (3) an automatically mapping scheme of laser beam energy onto discrete mesh elements of targets enable targets or laser beams be optimized without any additional interactive modeling or programming, and (4) significant computation algorithms are additionally presented to efficiently evaluate radiation symmetry on the target. Finally, examples are demonstrated to validate the significance of such unified modeling approach for physical experiments design and optimization in laser driven inertial confinement fusion.

  20. Signage by Design: A Design-Thinking Approach to Library User Experience

    Directory of Open Access Journals (Sweden)

    Edward Luca

    2016-01-01

    Full Text Available Signage is a powerful visual tool for communication and a crucial component of the library user experience. Signage can welcome, guide, instruct, and delight users, helping them navigate the complex information world of any library. In practice, however, signage can be problematic, revealing tensions between various stakeholders, and contributing to visual noise through information overload; this often leads to signage blindness, library anxiety, and confusion. This article explores how libraries can use a design-thinking approach to improve the user experience in physical library spaces, particularly with respect to signage, based on our experience at the UTS Library, a university library in Australia that serves the University of Technology Sydney (UTS. We found that a design-thinking approach that uses the processes of empathy, problem definition, solution ideation, prototyping, and testing, can help libraries make significant and meaningful changes that can be adopted at relatively low cost.

  1. Enhanced ergonomics approaches for product design: a user experience ecosystem perspective and case studies.

    Science.gov (United States)

    Xu, Wei

    2014-01-01

    This paper first discusses the major inefficiencies faced in current human factors and ergonomics (HFE) approaches: (1) delivering an optimal end-to-end user experience (UX) to users of a solution across its solution lifecycle stages; (2) strategically influencing the product business and technology capability roadmaps from a UX perspective and (3) proactively identifying new market opportunities and influencing the platform architecture capabilities on which the UX of end products relies. In response to these challenges, three case studies are presented to demonstrate how enhanced ergonomics design approaches have effectively addressed the challenges faced in current HFE approaches. Then, the enhanced ergonomics design approaches are conceptualised by a user-experience ecosystem (UXE) framework, from a UX ecosystem perspective. Finally, evidence supporting the UXE, the advantage and the formalised process for executing UXE and methodological considerations are discussed. Practitioner Summary: This paper presents enhanced ergonomics approaches to product design via three case studies to effectively address current HFE challenges by leveraging a systematic end-to-end UX approach, UX roadmaps and emerging UX associated with prioritised user needs and usages. Thus, HFE professionals can be more strategic, creative and influential.

  2. Virtual experiments: a new approach for improving process conceptualization in hillslope hydrology

    Science.gov (United States)

    Weiler, Markus; McDonnell, Jeff

    2004-01-01

    We present an approach for process conceptualization in hillslope hydrology. We develop and implement a series of virtual experiments, whereby the interaction between water flow pathways, source and mixing at the hillslope scale is examined within a virtual experiment framework. We define these virtual experiments as 'numerical experiments with a model driven by collective field intelligence'. The virtual experiments explore the first-order controls in hillslope hydrology, where the experimentalist and modeler work together to cooperatively develop and analyze the results. Our hillslope model for the virtual experiments (HillVi) in this paper is based on conceptualizing the water balance within the saturated and unsaturated zone in relation to soil physical properties in a spatially explicit manner at the hillslope scale. We argue that a virtual experiment model needs to be able to capture all major controls on subsurface flow processes that the experimentalist might deem important, while at the same time being simple with few 'tunable parameters'. This combination makes the approach, and the dialog between experimentalist and modeler, a useful hypothesis testing tool. HillVi simulates mass flux for different initial conditions under the same flow conditions. We analyze our results in terms of an artificial line source and isotopic hydrograph separation of water and subsurface flow. Our results for this first set of virtual experiments showed how drainable porosity and soil depth variability exert a first order control on flow and transport at the hillslope scale. We found that high drainable porosity soils resulted in a restricted water table rise, resulting in more pronounced channeling of lateral subsurface flow along the soil-bedrock interface. This in turn resulted in a more anastomosing network of tracer movement across the slope. The virtual isotope hydrograph separation showed higher proportions of event water with increasing drainable porosity. When

  3. Multilevel approach to mentoring in the Research Experiences for Undergraduates programs

    Science.gov (United States)

    Bonine, K. E.; Dontsova, K.; Pavao-Zuckerman, M.; Paavo, B.; Hogan, D.; Oberg, E.; Gay, J.

    2015-12-01

    This presentation focuses on different types of mentoring for students participating in Research Experiences for Undergraduates programs with examples, including some new approaches, from The Environmental and Earth Systems Research Experiences for Undergraduates Program at Biosphere 2. While traditional faculty mentors play essential role in students' development as researchers and professionals, other formal and informal mentoring can be important component of the REU program and student experiences. Students receive mentoring from program directors, coordinators, and on site undergraduate advisors. While working on their research projects, REU students receive essential support and mentoring from undergraduate and graduate students and postdoctoral scientists in the research groups of their primary mentors. Cohort living and group activities give multiple opportunities for peer mentoring where each student brings their own strengths and experiences to the group. Biosphere 2 REU program puts strong emphasis on teaching students to effectively communicate their research to public. In order to help REUs learn needed skills the outreach personnel at Biosphere 2 mentor and advise students both in groups and individually, in lecture format and by personal example, on best outreach approaches in general and on individual outreach projects students develop. To further enhance and strengthen outreach mentoring we used a novel approach of blending cohort of REU students with the Cal Poly STAR (STEM Teacher And Researcher) Program fellows, future K-12 STEM teachers who are gaining research experience at Biosphere 2. STAR fellows live together with the REU students and participate with them in professional development activities, as well as perform research side by side. Educational background and experiences gives these students a different view and better preparation and tools to effectively communicate and adapt science to lay audiences, a challenge commonly facing

  4. Approximation by planar elastic curves

    DEFF Research Database (Denmark)

    Brander, David; Gravesen, Jens; Nørbjerg, Toke Bjerge

    2016-01-01

    We give an algorithm for approximating a given plane curve segment by a planar elastic curve. The method depends on an analytic representation of the space of elastic curve segments, together with a geometric method for obtaining a good initial guess for the approximating curve. A gradient......-driven optimization is then used to find the approximating elastic curve....

  5. Evaluation of Effects of Warning Sign Position on Driving Behavior in Horizontal Sharp Curves

    Directory of Open Access Journals (Sweden)

    Xiao-hua Zhao

    2015-02-01

    Full Text Available In present time, the guidelines on warning sign position in the China National Standard lack detailed and standard regulations of placing warning signs on sharp curves, which may cause road safety problems. Therefore, this paper briefly discussed how to optimize the position of a warning sign on a sharp curve through a driving simulator experiment. This study concluded that a warning sign placed at different positions prior to a sharp curve will have different influence ranges for drivers approaching and negotiating the curve. Meanwhile, different positions of a warning sign imposed different effect obviously on the adjustment of vehicle's lane position on sharp curves with the same radius, especially at the midpoint of a sharp curve. The evaluation results of five positions (0 m, 50 m, 100 m, 200 m, and 400 m in advance showed that only when the warning signs were placed 100 m or 200 m prior to sharp curves, can they achieve positive influence on driving behavior. On this basis, the authors look forward to providing rationalization proposals in selecting the best position of a warning sign on a sharp curve for the engineering implementation and national standard.

  6. Estimating reaction rate constants: comparison between traditional curve fitting and curve resolution

    NARCIS (Netherlands)

    Bijlsma, S.; Boelens, H. F. M.; Hoefsloot, H. C. J.; Smilde, A. K.

    2000-01-01

    A traditional curve fitting (TCF) algorithm is compared with a classical curve resolution (CCR) approach for estimating reaction rate constants from spectral data obtained in time of a chemical reaction. In the TCF algorithm, reaction rate constants an estimated from the absorbance versus time data

  7. Power Curve Measurements REWS

    DEFF Research Database (Denmark)

    Gómez Arranz, Paula; Vesth, Allan

    This report describes the power curve measurements carried out on a given wind turbine in a chosen period. The measurements were carried out following the measurement procedure in the draft of IEC 61400-12-1 Ed.2 [1], with some deviations mostly regarding uncertainty calculation. Here, the refere......This report describes the power curve measurements carried out on a given wind turbine in a chosen period. The measurements were carried out following the measurement procedure in the draft of IEC 61400-12-1 Ed.2 [1], with some deviations mostly regarding uncertainty calculation. Here......, the reference wind speed used in the power curve is the equivalent wind speed obtained from lidar measurements at several heights between lower and upper blade tip, in combination with a hub height meteorological mast. The measurements have been performed using DTU’s measurement equipment, the analysis...

  8. Showing the Unsayable: Participatory Visual Approaches and the Constitution of 'Patient Experience' in Healthcare Quality Improvement.

    Science.gov (United States)

    Papoulias, Constantina

    2018-06-01

    This article considers the strengths and potential contributions of participatory visual methods for healthcare quality improvement research. It argues that such approaches may enable us to expand our understanding of 'patient experience' and of its potential for generating new knowledge for health systems. In particular, they may open up dimensions of people's engagement with services and treatments which exceed both the declarative nature of responses to questionnaires and the narrative sequencing of self reports gathered through qualitative interviewing. I will suggest that working with such methods may necessitate a more reflexive approach to the constitution of evidence in quality improvement work. To this end, the article will first consider the emerging rationale for the use of visual participatory methods in improvement before outlining the implications of two related approaches-photo-elicitation and PhotoVoice-for the constitution of 'experience'. It will then move to a participatory model for healthcare improvement work, Experience Based Co-Design (EBCD). It will argue that EBCD exemplifies both the strengths and the limitations of adequating visual participatory approaches to quality improvement ends. The article will conclude with a critical reflection on a small photographic study, in which the author participated, and which sought to harness service user perspectives for the design of psychiatric facilities, as a way of considering the potential contribution of visual participatory methods for quality improvement.

  9. Family members' involvement in psychiatric care: experiences of the healthcare professionals' approach and feeling of alienation.

    Science.gov (United States)

    Ewertzon, M; Lützén, K; Svensson, E; Andershed, B

    2010-06-01

    The involvement of family members in psychiatric care is important for the recovery of persons with psychotic disorders and subsequently reduces the burden on the family. Earlier qualitative studies suggest that the participation of family members can be limited by how they experience the professionals' approach, which suggests a connection to the concept of alienation. Thus, the aim of this study was in a national sample investigate family members' experiences of the psychiatric health care professionals' approach. Data were collected by the Family Involvement and Alienation Questionnaire. The median level and quartiles were used to describe the distributions and data were analysed with non-parametric statistical methods. Seventy family members of persons receiving psychiatric care participated in the study. The results indicate that a majority of the participants respond that they have experiencing a negative approach from the professionals, indicating lack of confirmation and cooperation. The results also indicate that a majority of the participants felt powerlessness and social isolation in the care being provided, indicating feelings of alienation. A significant but weak association was found between the family members' experiences of the professionals' approach and their feelings of alienation.

  10. Curved electromagnetic missiles

    International Nuclear Information System (INIS)

    Myers, J.M.; Shen, H.M.; Wu, T.T.

    1989-01-01

    Transient electromagnetic fields can exhibit interesting behavior in the limit of great distances from their sources. In situations of finite total radiated energy, the energy reaching a distant receiver can decrease with distance much more slowly than the usual r - 2 . Cases of such slow decrease have been referred to as electromagnetic missiles. All of the wide variety of known missiles propagate in essentially straight lines. A sketch is presented here of a missile that can follow a path that is strongly curved. An example of a curved electromagnetic missile is explicitly constructed and some of its properties are discussed. References to details available elsewhere are given

  11. Algebraic curves and cryptography

    CERN Document Server

    Murty, V Kumar

    2010-01-01

    It is by now a well-known paradigm that public-key cryptosystems can be built using finite Abelian groups and that algebraic geometry provides a supply of such groups through Abelian varieties over finite fields. Of special interest are the Abelian varieties that are Jacobians of algebraic curves. All of the articles in this volume are centered on the theme of point counting and explicit arithmetic on the Jacobians of curves over finite fields. The topics covered include Schoof's \\ell-adic point counting algorithm, the p-adic algorithms of Kedlaya and Denef-Vercauteren, explicit arithmetic on

  12. IGMtransmission: Transmission curve computation

    Science.gov (United States)

    Harrison, Christopher M.; Meiksin, Avery; Stock, David

    2015-04-01

    IGMtransmission is a Java graphical user interface that implements Monte Carlo simulations to compute the corrections to colors of high-redshift galaxies due to intergalactic attenuation based on current models of the Intergalactic Medium. The effects of absorption due to neutral hydrogen are considered, with particular attention to the stochastic effects of Lyman Limit Systems. Attenuation curves are produced, as well as colors for a wide range of filter responses and model galaxy spectra. Photometric filters are included for the Hubble Space Telescope, the Keck telescope, the Mt. Palomar 200-inch, the SUBARU telescope and UKIRT; alternative filter response curves and spectra may be readily uploaded.

  13. Projection-based curve clustering

    International Nuclear Information System (INIS)

    Auder, Benjamin; Fischer, Aurelie

    2012-01-01

    This paper focuses on unsupervised curve classification in the context of nuclear industry. At the Commissariat a l'Energie Atomique (CEA), Cadarache (France), the thermal-hydraulic computer code CATHARE is used to study the reliability of reactor vessels. The code inputs are physical parameters and the outputs are time evolution curves of a few other physical quantities. As the CATHARE code is quite complex and CPU time-consuming, it has to be approximated by a regression model. This regression process involves a clustering step. In the present paper, the CATHARE output curves are clustered using a k-means scheme, with a projection onto a lower dimensional space. We study the properties of the empirically optimal cluster centres found by the clustering method based on projections, compared with the 'true' ones. The choice of the projection basis is discussed, and an algorithm is implemented to select the best projection basis among a library of orthonormal bases. The approach is illustrated on a simulated example and then applied to the industrial problem. (authors)

  14. Evoked prior learning experience and approach to learning as predictors of academic achievement.

    Science.gov (United States)

    Trigwell, Keith; Ashwin, Paul; Millan, Elena S

    2013-09-01

    In separate studies and research from different perspectives, five factors are found to be among those related to higher quality outcomes of student learning (academic achievement). Those factors are higher self-efficacy, deeper approaches to learning, higher quality teaching, students' perceptions that their workload is appropriate, and greater learning motivation. University learning improvement strategies have been built on these research results. To investigate how students' evoked prior experience, perceptions of their learning environment, and their approaches to learning collectively contribute to academic achievement. This is the first study to investigate motivation and self-efficacy in the same educational context as conceptions of learning, approaches to learning and perceptions of the learning environment. Undergraduate students (773) from the full range of disciplines were part of a group of over 2,300 students who volunteered to complete a survey of their learning experience. On completing their degrees 6 and 18 months later, their academic achievement was matched with their learning experience survey data. A 77-item questionnaire was used to gather students' self-report of their evoked prior experience (self-efficacy, learning motivation, and conceptions of learning), perceptions of learning context (teaching quality and appropriate workload), and approaches to learning (deep and surface). Academic achievement was measured using the English honours degree classification system. Analyses were conducted using correlational and multi-variable (structural equation modelling) methods. The results from the correlation methods confirmed those found in numerous earlier studies. The results from the multi-variable analyses indicated that surface approach to learning was the strongest predictor of academic achievement, with self-efficacy and motivation also found to be directly related. In contrast to the correlation results, a deep approach to learning was

  15. Elementary particles in curved spaces

    International Nuclear Information System (INIS)

    Lazanu, I.

    2004-01-01

    The theories in particle physics are developed currently, in Minkowski space-time starting from the Poincare group. A physical theory in flat space can be seen as the limit of a more general physical theory in a curved space. At the present time, a theory of particles in curved space does not exist, and thus the only possibility is to extend the existent theories in these spaces. A formidable obstacle to the extension of physical models is the absence of groups of motion in more general Riemann spaces. A space of constant curvature has a group of motion that, although differs from that of a flat space, has the same number of parameters and could permit some generalisations. In this contribution we try to investigate some physical implications of the presumable existence of elementary particles in curved space. In de Sitter space (dS) the invariant rest mass is a combination of the Poincare rest mass and the generalised angular momentum of a particle and it permits to establish a correlation with the vacuum energy and with the cosmological constant. The consequences are significant because in an experiment the local structure of space-time departs from the Minkowski space and becomes a dS or AdS space-time. Discrete symmetry characteristics of the dS/AdS group suggest some arguments for the possible existence of the 'mirror matter'. (author)

  16. Microgenetic experiment in developmental psychology: A new approach to discover cognitive change

    Directory of Open Access Journals (Sweden)

    Matija Svetina

    2002-02-01

    Full Text Available Microgenetic experiment is relatively new tool in a developmental psychology research. It is primarily used in discovering broad range of cognitive processes such as the development of logical operations, memory and attention as well as beliefs or school adaptation. Designed as an extension of simple longitudinal and cross-sectional approaches it is convinient to research mental processes in all developmental stages of human being, from infancy to the old age. Microgenetic approach is characterised with repeated observations of behaviour. Observations are carried out in a relatively short period of time and yet they cover the whole interval between first appearance and stabilisation of a process in a subject. The microgenetic approach offers a good insight into the nature and development of the change. The article presents the general steps in both forming and performing of a microgenetic experiment, as well as the approaches used in the data analyses. On more general level, the article presents major practical and theoretical advantages and disadvantages of a microgenetic approach to be considered in the future.

  17. High resolution melting curve analysis targeting the HBB gene mutational hot-spot offers a reliable screening approach for all common as well as most of the rare beta-globin gene mutations in Bangladesh.

    Science.gov (United States)

    Islam, Md Tarikul; Sarkar, Suprovath Kumar; Sultana, Nusrat; Begum, Mst Noorjahan; Bhuyan, Golam Sarower; Talukder, Shezote; Muraduzzaman, A K M; Alauddin, Md; Islam, Mohammad Sazzadul; Biswas, Pritha Promita; Biswas, Aparna; Qadri, Syeda Kashfi; Shirin, Tahmina; Banu, Bilquis; Sadya, Salma; Hussain, Manzoor; Sarwardi, Golam; Khan, Waqar Ahmed; Mannan, Mohammad Abdul; Shekhar, Hossain Uddin; Chowdhury, Emran Kabir; Sajib, Abu Ashfaqur; Akhteruzzaman, Sharif; Qadri, Syed Saleheen; Qadri, Firdausi; Mannoor, Kaiissar

    2018-01-02

    Bangladesh lies in the global thalassemia belt, which has a defined mutational hot-spot in the beta-globin gene. The high carrier frequencies of beta-thalassemia trait and hemoglobin E-trait in Bangladesh necessitate a reliable DNA-based carrier screening approach that could supplement the use of hematological and electrophoretic indices to overcome the barriers of carrier screening. With this view in mind, the study aimed to establish a high resolution melting (HRM) curve-based rapid and reliable mutation screening method targeting the mutational hot-spot of South Asian and Southeast Asian countries that encompasses exon-1 (c.1 - c.92), intron-1 (c.92 + 1 - c.92 + 130) and a portion of exon-2 (c.93 - c.217) of the HBB gene which harbors more than 95% of mutant alleles responsible for beta-thalassemia in Bangladesh. Our HRM approach could successfully differentiate ten beta-globin gene mutations, namely c.79G > A, c.92 + 5G > C, c.126_129delCTTT, c.27_28insG, c.46delT, c.47G > A, c.92G > C, c.92 + 130G > C, c.126delC and c.135delC in heterozygous states from the wild type alleles, implying the significance of the approach for carrier screening as the first three of these mutations account for ~85% of total mutant alleles in Bangladesh. Moreover, different combinations of compound heterozygous mutations were found to generate melt curves that were distinct from the wild type alleles and from one another. Based on the findings, sixteen reference samples were run in parallel to 41 unknown specimens to perform direct genotyping of the beta-thalassemia specimens using HRM. The HRM-based genotyping of the unknown specimens showed 100% consistency with the sequencing result. Targeting the mutational hot-spot, the HRM approach could be successfully applied for screening of beta-thalassemia carriers in Bangladesh as well as in other countries of South Asia and Southeast Asia. The approach could be a useful supplement of hematological and

  18. Design of laser-generated shockwave experiments. An approach using analytic models

    International Nuclear Information System (INIS)

    Lee, Y.T.; Trainor, R.J.

    1980-01-01

    Two of the target-physics phenomena which must be understood before a clean experiment can be confidently performed are preheating due to suprathermal electrons and shock decay due to a shock-rarefaction interaction. Simple analytic models are described for these two processes and the predictions of these models are compared with those of the LASNEX fluid physics code. We have approached this work not with the view of surpassing or even approaching the reliability of the code calculations, but rather with the aim of providing simple models which may be used for quick parameter-sensitivity evaluations, while providing physical insight into the problems

  19. Learning from uncertain curves

    DEFF Research Database (Denmark)

    Mallasto, Anton; Feragen, Aasa

    2017-01-01

    We introduce a novel framework for statistical analysis of populations of nondegenerate Gaussian processes (GPs), which are natural representations of uncertain curves. This allows inherent variation or uncertainty in function-valued data to be properly incorporated in the population analysis. Us...

  20. Power Curve Measurements

    DEFF Research Database (Denmark)

    Federici, Paolo; Kock, Carsten Weber

    This report describes the power curve measurements performed with a nacelle LIDAR on a given wind turbine in a wind farm and during a chosen measurement period. The measurements and analysis are carried out in accordance to the guidelines in the procedure “DTU Wind Energy-E-0019” [1]. The reporting...

  1. Power Curve Measurements, FGW

    DEFF Research Database (Denmark)

    Vesth, Allan; Kock, Carsten Weber

    The report describes power curve measurements carried out on a given wind turbine. The measurements are carried out in accordance to Ref. [1]. A site calibration has been carried out; see Ref. [2], and the measured flow correction factors for different wind directions are used in the present...... analyze of power performance of the turbine....

  2. Power Curve Measurements

    DEFF Research Database (Denmark)

    Federici, Paolo; Vesth, Allan

    The report describes power curve measurements carried out on a given wind turbine. The measurements are carried out in accordance to Ref. [1]. A site calibration has been carried out; see Ref. [2], and the measured flow correction factors for different wind directions are used in the present...... analyze of power performance of the turbine....

  3. Power Curve Measurements

    DEFF Research Database (Denmark)

    Villanueva, Héctor; Gómez Arranz, Paula

    The report describes power curve measurements carried out on a given wind turbine. The measurements are carried out in accordance to Ref. [1]. A site calibration has been carried out; see Ref. [2], and the measured flow correction factors for different wind directions are used in the present...... analyze of power performance of the turbine...

  4. Carbon Lorenz Curves

    NARCIS (Netherlands)

    Groot, L.F.M.|info:eu-repo/dai/nl/073642398

    2008-01-01

    The purpose of this paper is twofold. First, it exhibits that standard tools in the measurement of income inequality, such as the Lorenz curve and the Gini-index, can successfully be applied to the issues of inequality measurement of carbon emissions and the equity of abatement policies across

  5. The Axial Curve Rotator.

    Science.gov (United States)

    Hunter, Walter M.

    This document contains detailed directions for constructing a device that mechanically produces the three-dimensional shape resulting from the rotation of any algebraic line or curve around either axis on the coordinate plant. The device was developed in response to student difficulty in visualizing, and thus grasping the mathematical principles…

  6. Nacelle lidar power curve

    DEFF Research Database (Denmark)

    Gómez Arranz, Paula; Wagner, Rozenn

    This report describes the power curve measurements performed with a nacelle LIDAR on a given wind turbine in a wind farm and during a chosen measurement period. The measurements and analysis are carried out in accordance to the guidelines in the procedure “DTU Wind Energy-E-0019” [1]. The reporting...

  7. Power curve report

    DEFF Research Database (Denmark)

    Vesth, Allan; Kock, Carsten Weber

    The report describes power curve measurements carried out on a given wind turbine. The measurements are carried out in accordance to Ref. [1]. A site calibration has been carried out; see Ref. [2], and the measured flow correction factors for different wind directions are used in the present...

  8. Textbook Factor Demand Curves.

    Science.gov (United States)

    Davis, Joe C.

    1994-01-01

    Maintains that teachers and textbook graphics follow the same basic pattern in illustrating changes in demand curves when product prices increase. Asserts that the use of computer graphics will enable teachers to be more precise in their graphic presentation of price elasticity. (CFR)

  9. ECM using Edwards curves

    NARCIS (Netherlands)

    Bernstein, D.J.; Birkner, P.; Lange, T.; Peters, C.P.

    2013-01-01

    This paper introduces EECM-MPFQ, a fast implementation of the elliptic-curve method of factoring integers. EECM-MPFQ uses fewer modular multiplications than the well-known GMP-ECM software, takes less time than GMP-ECM, and finds more primes than GMP-ECM. The main improvements above the

  10. Power Curve Measurements FGW

    DEFF Research Database (Denmark)

    Federici, Paolo; Kock, Carsten Weber

    The report describes power curve measurements carried out on a given wind turbine. The measurements are carried out in accordance to Ref. [1]. A site calibration has been carried out; see Ref. [2], and the measured flow correction factors for different wind directions are used in the present...... analyze of power performance of the turbine...

  11. Applicable regulations and development of surveillance experiments of criticality approach in the TRIGA III Mark reactor

    International Nuclear Information System (INIS)

    Gonzalez M, J.L.; Aguilar H, F.; Rivero G, T.; Sainz M, E.

    2000-01-01

    In the procedure elaborated to repair the vessel of TRIGA III Mark reactor is required to move toward two tanks of temporal storage the fuel elements which are in operation and the spent fuel elements which are in decay inside the reactor pool. The National Commission of Nuclear Safety and Safeguards (CNSNS) has requested as protection measure that it is carried out a surveillance of the criticality approach of the temporal storages. This work determines the main regulation aspects that entails an experiment of criticality approach, moreover, informing about the results obtained in the developing of this experiments. The regulation aspects are not exclusives for this work in the TRIGA Mark III reactor but they also apply toward any assembling of fissile material. (Author)

  12. Revisiting the cape cod bacteria injection experiment using a stochastic modeling approach

    Science.gov (United States)

    Maxwell, R.M.; Welty, C.; Harvey, R.W.

    2007-01-01

    Bromide and resting-cell bacteria tracer tests conducted in a sandy aquifer at the U.S. Geological Survey Cape Cod site in 1987 were reinterpreted using a three-dimensional stochastic approach. Bacteria transport was coupled to colloid filtration theory through functional dependence of local-scale colloid transport parameters upon hydraulic conductivity and seepage velocity in a stochastic advection - dispersion/attachment - detachment model. Geostatistical information on the hydraulic conductivity (K) field that was unavailable at the time of the original test was utilized as input. Using geostatistical parameters, a groundwater flow and particle-tracking model of conservative solute transport was calibrated to the bromide-tracer breakthrough data. An optimization routine was employed over 100 realizations to adjust the mean and variance ofthe natural-logarithm of hydraulic conductivity (InK) field to achieve best fit of a simulated, average bromide breakthrough curve. A stochastic particle-tracking model for the bacteria was run without adjustments to the local-scale colloid transport parameters. Good predictions of mean bacteria breakthrough were achieved using several approaches for modeling components of the system. Simulations incorporating the recent Tufenkji and Elimelech (Environ. Sci. Technol. 2004, 38, 529-536) correlation equation for estimating single collector efficiency were compared to those using the older Rajagopalan and Tien (AIChE J. 1976, 22, 523-533) model. Both appeared to work equally well at predicting mean bacteria breakthrough using a constant mean bacteria diameter for this set of field conditions. Simulations using a distribution of bacterial cell diameters available from original field notes yielded a slight improvement in the model and data agreement compared to simulations using an average bacterial diameter. The stochastic approach based on estimates of local-scale parameters for the bacteria-transport process reasonably captured

  13. Developments in Interpreting Learning Curves and Applications to Energy Technology Policy

    International Nuclear Information System (INIS)

    Van der Zwaan, B.C.C.; Wene, C.O.

    2011-01-01

    The book 'Learning Curves: Theory, Models, and Applications' first draws a learning map that shows where learning is involved within organizations, then examines how it can be sustained, perfected, and accelerated. The book reviews empirical findings in the literature in terms of different sources for learning and partial assessments of the steps that make up the actual learning process inside the learning curve. Chapter 23 on 'Developments in Interpreting Learning Curves and Applications to Energy Technology Policy' is written by Bob van der Zwaan and Clas-Otto Wene. In this chapter they provide some interpretations of experience and learning curves starting from three different theoretical platforms. These interpretations are aimed at explaining learning rates for different energy technologies. The ultimate purpose is to find the role that experience and learning curves can legitimately play in designing efficient government deployment programs and in analyzing the implications of different energy scenarios. The 'Component Learning' section summarizes recent work by the authors that focuses on the disaggregation of technologies in their respective components and argues that traditional learning for overall technology should perhaps be replaced by a phenomenology that recognizes learning for individual components. The 'Learning and Time' section presents an approach that departs more strongly from the conventional learning curve methodology, by suggesting that exponential growth and progress may be the deeper underlying processes behind observed learning-by-doing. Contrary to this view, the cybernetic approach presented in the 'Cybernetic Approach' section sees learning curves as expressing a fundamental property of organizations in competitive markets and applies the findings from second order cybernetics to calculate the learning rates for operationally closed systems. All three interpretations find empirical support. The 'Conclusions' section summarizes the

  14. Developments in Interpreting Learning Curves and Applications to Energy Technology Policy

    Energy Technology Data Exchange (ETDEWEB)

    Van der Zwaan, B.C.C. [Energy research Centre of the Netherlands, ECN Policy Studies, Petten (Netherlands); Wene, C.O. [Wenergy, Lund (Sweden)

    2011-06-15

    The book 'Learning Curves: Theory, Models, and Applications' first draws a learning map that shows where learning is involved within organizations, then examines how it can be sustained, perfected, and accelerated. The book reviews empirical findings in the literature in terms of different sources for learning and partial assessments of the steps that make up the actual learning process inside the learning curve. Chapter 23 on 'Developments in Interpreting Learning Curves and Applications to Energy Technology Policy' is written by Bob van der Zwaan and Clas-Otto Wene. In this chapter they provide some interpretations of experience and learning curves starting from three different theoretical platforms. These interpretations are aimed at explaining learning rates for different energy technologies. The ultimate purpose is to find the role that experience and learning curves can legitimately play in designing efficient government deployment programs and in analyzing the implications of different energy scenarios. The 'Component Learning' section summarizes recent work by the authors that focuses on the disaggregation of technologies in their respective components and argues that traditional learning for overall technology should perhaps be replaced by a phenomenology that recognizes learning for individual components. The 'Learning and Time' section presents an approach that departs more strongly from the conventional learning curve methodology, by suggesting that exponential growth and progress may be the deeper underlying processes behind observed learning-by-doing. Contrary to this view, the cybernetic approach presented in the 'Cybernetic Approach' section sees learning curves as expressing a fundamental property of organizations in competitive markets and applies the findings from second order cybernetics to calculate the learning rates for operationally closed systems. All three interpretations find empirical

  15. Presurized water reactor safety approach and analysis. From conception to experience feedback

    International Nuclear Information System (INIS)

    Libmann, J.

    1987-04-01

    This report deals in ten chapters, with the following subjects: 1. Safety approach methods; 2. Study of accidents; 3. Safety analysis; 4. Study of internal aggressions or those involved by the site; 5. Consideration of complementary situations; 6. Three Mile Island accident; 7. Safety during operation and experience feedback; 8. An example of analysis: steam generator closure plug; 9. Probabilistic safety evaluation; 10. Chernobyl accident. 30 refs [fr

  16. Signal Attenuation Curve for Different Surface Detector Arrays

    Science.gov (United States)

    Vicha, J.; Travnicek, P.; Nosek, D.; Ebr, J.

    2014-06-01

    Modern cosmic ray experiments consisting of large array of particle detectors measure the signals of electromagnetic or muon components or their combination. The correction for an amount of atmosphere passed is applied to the surface detector signal before its conversion to the shower energy. Either Monte Carlo based approach assuming certain composition of primaries or indirect estimation using real data and assuming isotropy of arrival directions can be used. Toy surface arrays of different sensitivities to electromagnetic and muon components are assumed in MC simulations to study effects imposed on attenuation curves for varying composition or possible high energy anisotropy. The possible sensitivity of the attenuation curve to the mass composition is also tested for different array types focusing on a future apparatus that can separate muon and electromagnetic component signals.

  17. Computational Experiment Approach to Controlled Evolution of Procurement Pattern in Cluster Supply Chain

    Directory of Open Access Journals (Sweden)

    Xiao Xue

    2015-01-01

    Full Text Available Companies have been aware of the benefits of developing Cluster Supply Chains (CSCs, and they are spending a great deal of time and money attempting to develop the new business pattern. Yet, the traditional techniques for identifying CSCs have strong theoretical antecedents, but seem to have little traction in the field. We believe this is because the standard techniques fail to capture evolution over time, nor provide useful intervention measures to reach goals. To address these problems, we introduce an agent-based modeling approach to evaluate CSCs. Taking collaborative procurement as research object, our approach is composed of three parts: model construction, model instantiation, and computational experiment. We use the approach to explore the service charging policy problem in collaborative procurement. Three kinds of service charging polices are compared in the same experiment environment. Finally, “Fixed Cost” is identified as the optimal policy under the stable market environment. The case study can help us to understand the workflow of applying the approach, and provide valuable decision support applications to industry.

  18. Mental Health Experiences of Older Adults Living with HIV: Uncertainty, Stigma, and Approaches to Resilience.

    Science.gov (United States)

    Furlotte, Charles; Schwartz, Karen

    2017-06-01

    This study describes the mental health experiences of older adults living with HIV in Ottawa. Eleven participants aged 52 to 67 completed in-depth personal interviews. Mental health concerns pervaded the lives of these older adults. We identified three central themes common to the participants' stories: uncertainty, stigma, and resilience. For some of these participants, uncertainty impacting mental health centred on unexpected survival; interpretation of one's symptoms; and medical uncertainty. Participants' experiences of stigma included discrimination in health care interactions; misinformation; feeling stigmatized due to aspects of their physical appearance; compounded stigma; and anticipated stigma. Participants reported using several coping strategies, which we frame as individual approaches to resilience. These strategies include reducing the space that HIV takes up in one's life; making lifestyle changes to accommodate one's illness; and engaging with social support. These findings inform understandings of services for people aging with HIV who may experience mental health concerns.

  19. A new approach to designing reduced scale thermal-hydraulic experiments

    International Nuclear Information System (INIS)

    Lapa, Celso M.F.; Sampaio, Paulo A.B. de; Pereira, Claudio M.N.A.

    2004-01-01

    Reduced scale experiments are often employed in engineering because they are much cheaper than real scale testing. Unfortunately, though, it is difficult to design a thermal-hydraulic circuit or equipment in reduced scale capable of reproducing, both accurately and simultaneously, all the physical phenomena that occur in real scale and operating conditions. This paper presents a methodology to designing thermal-hydraulic experiments in reduced scale based on setting up a constrained optimization problem that is solved using genetic algorithms (GAs). In order to demonstrate the application of the methodology proposed, we performed some investigations in the design of a heater aimed to simulate the transport of heat and momentum in the core of a pressurized water reactor (PWR) at 100% of nominal power and non-accident operating conditions. The results obtained show that the proposed methodology is a promising approach for designing reduced scale experiments

  20. Parametric representation of centrifugal pump homologous curves

    International Nuclear Information System (INIS)

    Veloso, Marcelo A.; Mattos, Joao R.L. de

    2015-01-01

    Essential for any mathematical model designed to simulate flow transient events caused by pump operations is the pump performance data. The performance of a centrifugal pump is characterized by four basic quantities: the rotational speed, the volumetric flow rate, the dynamic head, and the hydraulic torque. The curves showing the relationships between these four variables are called the pump characteristic curves. The characteristic curves are empirically developed by the pump manufacturer and uniquely describe head and torque as functions of volumetric flow rate and rotation speed. Because of comprising a large amount of points, this configuration is not suitable for computational purposes. However, it can be converted to a simpler form by the development of the homologous curves, in which dynamic head and hydraulic torque ratios are expressed as functions of volumetric flow and rotation speed ratios. The numerical use of the complete set of homologous curves requires specification of sixteen partial curves, being eight for the dynamic head and eight for the hydraulic torque. As a consequence, the handling of homologous curves is still somewhat complicated. In solving flow transient problems that require the pump characteristic data for all the operation zones, the parametric form appears as the simplest way to deal with the homologous curves. In this approach, the complete characteristics of a pump can be described by only two closed curves, one for the dynamic head and other for the hydraulic torque, both in function of a single angular coordinate defined adequately in terms of the quotient between volumetric flow ratio and rotation speed ratio. The usefulness and advantages of this alternative method are demonstrated through a practical example in which the homologous curves for a pump of the type used in the main coolant loops of a pressurized water reactor (PWR) are transformed to the parametric form. (author)

  1. Codes and curves

    CERN Document Server

    Walker, Judy L

    2000-01-01

    When information is transmitted, errors are likely to occur. Coding theory examines efficient ways of packaging data so that these errors can be detected, or even corrected. The traditional tools of coding theory have come from combinatorics and group theory. Lately, however, coding theorists have added techniques from algebraic geometry to their toolboxes. In particular, by re-interpreting the Reed-Solomon codes, one can see how to define new codes based on divisors on algebraic curves. For instance, using modular curves over finite fields, Tsfasman, Vladut, and Zink showed that one can define a sequence of codes with asymptotically better parameters than any previously known codes. This monograph is based on a series of lectures the author gave as part of the IAS/PCMI program on arithmetic algebraic geometry. Here, the reader is introduced to the exciting field of algebraic geometric coding theory. Presenting the material in the same conversational tone of the lectures, the author covers linear codes, inclu...

  2. Carbon Lorenz Curves

    Energy Technology Data Exchange (ETDEWEB)

    Groot, L. [Utrecht University, Utrecht School of Economics, Janskerkhof 12, 3512 BL Utrecht (Netherlands)

    2008-11-15

    The purpose of this paper is twofold. First, it exhibits that standard tools in the measurement of income inequality, such as the Lorenz curve and the Gini-index, can successfully be applied to the issues of inequality measurement of carbon emissions and the equity of abatement policies across countries. These tools allow policy-makers and the general public to grasp at a single glance the impact of conventional distribution rules such as equal caps or grandfathering, or more sophisticated ones, on the distribution of greenhouse gas emissions. Second, using the Samuelson rule for the optimal provision of a public good, the Pareto-optimal distribution of carbon emissions is compared with the distribution that follows if countries follow Nash-Cournot abatement strategies. It is shown that the Pareto-optimal distribution under the Samuelson rule can be approximated by the equal cap division, represented by the diagonal in the Lorenz curve diagram.

  3. The environmental Kuznets curve. Does one size fit all?

    International Nuclear Information System (INIS)

    List, J.A.; Gallet, C.A.

    1999-01-01

    This paper uses a new panel data set on state-level sulfur dioxide and nitrogen oxide emissions from 1929-1994 to test the appropriateness of the 'one size fits all' reduced-form regression approach commonly used in the environmental Kuznets curve literature. Empirical results provide initial evidence that an inverted-U shape characterizes the relationship between per capita emissions and per capita incomes at the state level. Parameter estimates suggest, however, that previous studies, which restrict cross-sections to undergo identical experiences over time, may be presenting statistically biased results. 25 refs

  4. Dynamics of curved fronts

    CERN Document Server

    Pelce, Pierre

    1989-01-01

    In recent years, much progress has been made in the understanding of interface dynamics of various systems: hydrodynamics, crystal growth, chemical reactions, and combustion. Dynamics of Curved Fronts is an important contribution to this field and will be an indispensable reference work for researchers and graduate students in physics, applied mathematics, and chemical engineering. The book consist of a 100 page introduction by the editor and 33 seminal articles from various disciplines.

  5. International Wage Curves

    OpenAIRE

    David G. Blanchflower; Andrew J. Oswald

    1992-01-01

    The paper provides evidence for the existence of a negatively sloped locus linking the level of pay to the rate of regional (or industry) unemployment. This "wage curve" is estimated using microeconomic data for Britain, the US, Canada, Korea, Austria, Italy, Holland, Switzerland, Norway, and Germany, The average unemployment elasticity of pay is approximately -0.1. The paper sets out a multi-region efficiency wage model and argues that its predictions are consistent with the data.

  6. LCC: Light Curves Classifier

    Science.gov (United States)

    Vo, Martin

    2017-08-01

    Light Curves Classifier uses data mining and machine learning to obtain and classify desired objects. This task can be accomplished by attributes of light curves or any time series, including shapes, histograms, or variograms, or by other available information about the inspected objects, such as color indices, temperatures, and abundances. After specifying features which describe the objects to be searched, the software trains on a given training sample, and can then be used for unsupervised clustering for visualizing the natural separation of the sample. The package can be also used for automatic tuning parameters of used methods (for example, number of hidden neurons or binning ratio). Trained classifiers can be used for filtering outputs from astronomical databases or data stored locally. The Light Curve Classifier can also be used for simple downloading of light curves and all available information of queried stars. It natively can connect to OgleII, OgleIII, ASAS, CoRoT, Kepler, Catalina and MACHO, and new connectors or descriptors can be implemented. In addition to direct usage of the package and command line UI, the program can be used through a web interface. Users can create jobs for ”training” methods on given objects, querying databases and filtering outputs by trained filters. Preimplemented descriptors, classifier and connectors can be picked by simple clicks and their parameters can be tuned by giving ranges of these values. All combinations are then calculated and the best one is used for creating the filter. Natural separation of the data can be visualized by unsupervised clustering.

  7. Comparative experiments regarding approaches to feedforward hysteresis compensation for piezoceramic actuators

    International Nuclear Information System (INIS)

    Gu, Guo-Ying; Zhu, Li-Min

    2014-01-01

    Piezoceramic actuators (PCAs) are desired devices in many micro/nano-positioning applications. The performance of PCA-based applications is severely limited by the presence of hysteresis nonlinearity. To remedy the hysteresis nonlinearity in such systems, feedforward hysteresis compensation is the most common technique. In the literature, many different feedforward hysteresis compensation approaches have been developed, but there are no comparative studies of these approaches. Focusing on the modified Prandtl-Ishlinskii model (MPIM) for asymmetric hysteresis description of piezoceramic actuators, three feedforward hysteresis compensation approaches—inverse hysteresis compensation (IHC), without inverse hysteresis compensation (WIHC), and direct inverse hysteresis compensation (DIHC)—are developed and compared in this paper. Extensive comparative experiments were conducted on a PCA-actuated stage to verify the effectiveness of the three different feedforward control approaches to hysteresis compensation. The experimental results show that the performances among the three approaches are rather similar, and the main differences among them are due to the specific implementation of each approach. (paper)

  8. Building international experiences into an engineering curriculum - a design project-based approach

    Science.gov (United States)

    Maldonado, Victor; Castillo, Luciano; Carbajal, Gerardo; Hajela, Prabhat

    2014-07-01

    This paper is a descriptive account of how short-term international and multicultural experiences can be integrated into early design experiences in an aerospace engineering curriculum. Such approaches are considered as important not only in fostering a student's interest in the engineering curriculum, but also exposing them to a multicultural setting that they are likely to encounter in their professional careers. In the broader sense, this programme is described as a model that can be duplicated in other engineering disciplines as a first-year experience. In this study, undergraduate students from Rensselaer Polytechnic Institute (RPI) and Universidad del Turabo (UT) in Puerto Rico collaborated on a substantial design project consisting of designing, fabricating, and flight-testing radio-controlled model aircraft as a capstone experience in a semester-long course on Fundamentals of Flight. The two-week long experience in Puerto Rico was organised into academic and cultural components designed with the following objectives: (i) to integrate students in a multicultural team-based academic and social environment, (ii) to practise team-building skills and develop students' critical thinking and analytical skills, and finally (iii) to excite students about their engineering major through practical applications of aeronautics and help them decide if it is a right fit for them.

  9. Modernized Approach for Generating Reproducible Heterogeneity Using Transmitted-Light for Flow Visualization Experiments

    Science.gov (United States)

    Jones, A. A.; Holt, R. M.

    2017-12-01

    Image capturing in flow experiments has been used for fluid mechanics research since the early 1970s. Interactions of fluid flow between the vadose zone and permanent water table are of great interest because this zone is responsible for all recharge waters, pollutant transport and irrigation efficiency for agriculture. Griffith, et al. (2011) developed an approach where constructed reproducible "geologically realistic" sand configurations are deposited in sandfilled experimental chambers for light-transmitted flow visualization experiments. This method creates reproducible, reverse graded, layered (stratified) thin-slab sand chambers for point source experiments visualizing multiphase flow through porous media. Reverse-graded stratification of sand chambers mimic many naturally occurring sedimentary deposits. Sandfilled chambers use light as nonintrusive tools for measuring water saturation in two-dimensions (2-D). Homogeneous and heterogeneous sand configurations can be produced to visualize the complex physics of the unsaturated zone. The experimental procedure developed by Griffith, et al. (2011) was designed using now outdated and obsolete equipment. We have modernized this approach with new Parker Deadel linear actuator and programed projects/code for multiple configurations. We have also updated the Roper CCD software and image processing software with the latest in industry standards. Modernization of transmitted-light source, robotic equipment, redesigned experimental chambers, and newly developed analytical procedures have greatly reduced time and cost per experiment. We have verified the ability of the new equipment to generate reproducible heterogeneous sand-filled chambers and demonstrated the functionality of the new equipment and procedures by reproducing several gravity-driven fingering experiments conducted by Griffith (2008).

  10. A formal concept analysis approach to consensus clustering of multi-experiment expression data

    Science.gov (United States)

    2014-01-01

    Background Presently, with the increasing number and complexity of available gene expression datasets, the combination of data from multiple microarray studies addressing a similar biological question is gaining importance. The analysis and integration of multiple datasets are expected to yield more reliable and robust results since they are based on a larger number of samples and the effects of the individual study-specific biases are diminished. This is supported by recent studies suggesting that important biological signals are often preserved or enhanced by multiple experiments. An approach to combining data from different experiments is the aggregation of their clusterings into a consensus or representative clustering solution which increases the confidence in the common features of all the datasets and reveals the important differences among them. Results We propose a novel generic consensus clustering technique that applies Formal Concept Analysis (FCA) approach for the consolidation and analysis of clustering solutions derived from several microarray datasets. These datasets are initially divided into groups of related experiments with respect to a predefined criterion. Subsequently, a consensus clustering algorithm is applied to each group resulting in a clustering solution per group. These solutions are pooled together and further analysed by employing FCA which allows extracting valuable insights from the data and generating a gene partition over all the experiments. In order to validate the FCA-enhanced approach two consensus clustering algorithms are adapted to incorporate the FCA analysis. Their performance is evaluated on gene expression data from multi-experiment study examining the global cell-cycle control of fission yeast. The FCA results derived from both methods demonstrate that, although both algorithms optimize different clustering characteristics, FCA is able to overcome and diminish these differences and preserve some relevant biological

  11. Classification of ASKAP Vast Radio Light Curves

    Science.gov (United States)

    Rebbapragada, Umaa; Lo, Kitty; Wagstaff, Kiri L.; Reed, Colorado; Murphy, Tara; Thompson, David R.

    2012-01-01

    The VAST survey is a wide-field survey that observes with unprecedented instrument sensitivity (0.5 mJy or lower) and repeat cadence (a goal of 5 seconds) that will enable novel scientific discoveries related to known and unknown classes of radio transients and variables. Given the unprecedented observing characteristics of VAST, it is important to estimate source classification performance, and determine best practices prior to the launch of ASKAP's BETA in 2012. The goal of this study is to identify light curve characterization and classification algorithms that are best suited for archival VAST light curve classification. We perform our experiments on light curve simulations of eight source types and achieve best case performance of approximately 90% accuracy. We note that classification performance is most influenced by light curve characterization rather than classifier algorithm.

  12. Ten ways to design for disgust, sadness, and other enjoyments: A design approach to enrich product experiences with negative emotions

    OpenAIRE

    Fokkinga, S.F.; Desmet, P.M.A.

    2013-01-01

    This paper demonstrates how designers can enrich user experiences by purposefully involving negative emotions in user-product interaction. This approach is derived from a framework of rich experience, which explains how and under what circumstances negative emotions make a product experience richer and enjoyable. The approach consists of three steps, where the designer decides 1) which negative emotion is most appropriate for the user context; 2) how and when this emotion is best elicited; an...

  13. Learning curves in health professions education.

    Science.gov (United States)

    Pusic, Martin V; Boutis, Kathy; Hatala, Rose; Cook, David A

    2015-08-01

    Learning curves, which graphically show the relationship between learning effort and achievement, are common in published education research but are not often used in day-to-day educational activities. The purpose of this article is to describe the generation and analysis of learning curves and their applicability to health professions education. The authors argue that the time is right for a closer look at using learning curves-given their desirable properties-to inform both self-directed instruction by individuals and education management by instructors.A typical learning curve is made up of a measure of learning (y-axis), a measure of effort (x-axis), and a mathematical linking function. At the individual level, learning curves make manifest a single person's progress towards competence including his/her rate of learning, the inflection point where learning becomes more effortful, and the remaining distance to mastery attainment. At the group level, overlaid learning curves show the full variation of a group of learners' paths through a given learning domain. Specifically, they make overt the difference between time-based and competency-based approaches to instruction. Additionally, instructors can use learning curve information to more accurately target educational resources to those who most require them.The learning curve approach requires a fine-grained collection of data that will not be possible in all educational settings; however, the increased use of an assessment paradigm that explicitly includes effort and its link to individual achievement could result in increased learner engagement and more effective instructional design.

  14. Ten ways to design for disgust, sadness, and other enjoyments : A design approach to enrich product experiences with negative emotions

    NARCIS (Netherlands)

    Fokkinga, S.F.; Desmet, P.M.A.

    2013-01-01

    This paper demonstrates how designers can enrich user experiences by purposefully involving negative emotions in user-product interaction. This approach is derived from a framework of rich experience, which explains how and under what circumstances negative emotions make a product experience richer

  15. A Cultural Approach to Understanding Professional Experiences of Foreign-Born Faculty in U.S. Educational Leadership Preparation Programs

    Science.gov (United States)

    Khrabrova, Iryna; Sanzo, Karen L.

    2013-01-01

    The purpose of this study was to investigate the professional experiences of foreign-born faculty members serving in U.S. educational leadership preparation programs, utilizing a cultural approach to discern their lived experiences related to professional life. Cultural values were explored as reflected in professional life experiences. The…

  16. Comparative analysis of stakeholder experiences with an online approach to prioritizing patient-centered research topics.

    Science.gov (United States)

    Khodyakov, Dmitry; Grant, Sean; Meeker, Daniella; Booth, Marika; Pacheco-Santivanez, Nathaly; Kim, Katherine K

    2017-05-01

    Little evidence exists about effective and scalable methods for meaningful stakeholder engagement in research. We explored patient/caregiver experiences with a high-tech online engagement approach for patient-centered research prioritization, compared their experiences with those of professional stakeholders, and identified factors associated with favorable participant experiences. We conducted 8 online modified-Delphi (OMD) panels. Panelists participated in 2 rating rounds with a statistical feedback/online discussion round in between. Panels focused on weight management/obesity, heart failure, and Kawasaki disease. We recruited a convenience sample of adults with any of the 3 conditions (or parents/guardians of Kawasaki disease patients), clinicians, and researchers. Measures included self-reported willingness to use OMD again, the panelists' study participation and online discussion experiences, the system's perceived ease of use, and active engagement metrics. Out of 349 panelists, 292 (84%) completed the study. Of those, 46% were patients, 36% were clinicians, and 19% were researchers. In multivariate models, patients were not significantly more actively engaged (Odds ratio (OR) = 1.69, 95% confidence interval (CI), 0.94-3.05) but had more favorable study participation (β = 0.49; P  ≤ .05) and online discussion (β = 0.18; P  ≤ .05) experiences and were more willing to use OMD again (β = 0.36; P  ≤ .05), compared to professional stakeholders. Positive perceptions of the OMD system's ease of use (β = 0.16; P  ≤ .05) and favorable study participation (β = 0.26; P  ≤ .05) and online discussion (β = 0.57; P  ≤ .05) experiences were also associated with increased willingness to use OMD in the future. Active engagement was not associated with online experience indices or willingness to use OMD again. Online approaches to engaging large numbers of stakeholders are a promising and efficient adjunct

  17. Humanistic approach to nursing education: lived experiences of Iranian nursing students.

    Science.gov (United States)

    Ghiyasvandian, Shahrzad; Bolourchifard, Fariba; Parsa Yekta, Zohreh

    2014-09-28

    The nurse teachers tried to have a complete understanding of the educational contents, to transfer knowledge to nursing students better, and to facilitate the process of education. The purpose of this study was to explore the lived experiences of Iranian nursing students regarding the characteristics of academic nurse teachers. In this hermeneutic phenomenological study, data were collected via in-depth, semi-structured interviews with 12 Iranian nursing students and the audio-taped and transcribed interviews analyzed according to Van Manen´s method. The main theme emerged during data analysis, was "humanistic approach to nursing education". The theme was extracted from 2 sub-themes including 'ethical necessities' and 'effective interaction'. The findings present greater understanding of humanistic approach to nursing education.

  18. The constant experience of self: conceptual approaches between Dewey and Mead

    Directory of Open Access Journals (Sweden)

    Tiago Barcelos Pereira Salgado

    2012-09-01

    Full Text Available We look at our article on a relational communicationapproach. In this sense, we seek to understandthe communication process from a praxeologicalmodel as elaborated by Louis Quéré (1991,rather than an epistemological model, seized in earlierformulations about the communicative practice.With pragmatism as a guideline of our argument,we are interested in understand and approach thenotions of self and experience as discussed by JohnDewey (1896, 1980, 2010 and George Herbert Mead(1934. Both concepts seem appropriate to thinkabout communication. Our purpose is then to seeto what extent we can reasonably argue that the selfis in constant experience and the implications thatpermeate this conceptual relationship.

  19. Advanced approach to the analysis of a series of in-situ nuclear forward scattering experiments

    Energy Technology Data Exchange (ETDEWEB)

    Vrba, Vlastimil, E-mail: vlastimil.vrba01@upol.cz [Department of Experimental Physics, Faculty of Science, Palacký University Olomouc, 17. listopadu 12, 771 46 Olomouc (Czech Republic); Procházka, Vít, E-mail: v.prochazka@upol.cz [Department of Experimental Physics, Faculty of Science, Palacký University Olomouc, 17. listopadu 12, 771 46 Olomouc (Czech Republic); Smrčka, David, E-mail: david.smrcka@upol.cz [Department of Experimental Physics, Faculty of Science, Palacký University Olomouc, 17. listopadu 12, 771 46 Olomouc (Czech Republic); Miglierini, Marcel, E-mail: marcel.miglierini@stuba.sk [Slovak University of Technology in Bratislava, Faculty of Electrical Engineering and Information Technology, Institute of Nuclear and Physical Engineering, Ilkovicova 3, 812 19 Bratislava (Slovakia); Department of Nuclear Reactors, Faculty of Nuclear Science and Physical Engineering, Czech Technical University in Prague, V Holešovičkách 2, 180 00 Prague (Czech Republic)

    2017-03-01

    This study introduces a sequential fitting procedure as a specific approach to nuclear forward scattering (NFS) data evaluation. Principles and usage of this advanced evaluation method are described in details and its utilization is demonstrated on NFS in-situ investigations of fast processes. Such experiments frequently consist of hundreds of time spectra which need to be evaluated. The introduced procedure allows the analysis of these experiments and significantly decreases the time needed for the data evaluation. The key contributions of the study are the sequential use of the output fitting parameters of a previous data set as the input parameters for the next data set and the model suitability crosscheck option of applying the procedure in ascending and descending directions of the data sets. Described fitting methodology is beneficial for checking of model validity and reliability of obtained results.

  20. Experiences of nonrecognition among offshore workers in the Campos basin: an approach based on Axel Honneth

    Directory of Open Access Journals (Sweden)

    Adelia Maria Miglievich Ribeiro

    2011-11-01

    Full Text Available Our research focused on a specific group of workers – those employed in the petroleum industry in the Campos Basin (RJ by Petrobrás – and service providers. Their interviews provide empirical material for a possible new approach to the offshore workers’ environment based on some issues raised by Axel Honneth, current Critical Theory’s exponent, such as the experience of disrespect, moral feelings of indignation, and his articulation in search for solutions to configure or not a struggle for recognition. We attest the analytical potential of the Honnethian premises in guiding empirical investigations which may lead to the review of the production relationship as a space to experience the claim for its humanization within advanced capitalism, in which the tendency to individualistic and conformist solutions prevail as they are triggered by the concurrent work precariousness.

  1. Rigorous approach to the comparison between experiment and theory in Casimir force measurements

    International Nuclear Information System (INIS)

    Klimchitskaya, G L; Chen, F; Decca, R S; Fischbach, E; Krause, D E; Lopez, D; Mohideen, U; Mostepanenko, V M

    2006-01-01

    In most experiments on the Casimir force the comparison between measurement data and theory was done using the concept of the root-mean-square deviation, a procedure that has been criticized in the literature. Here we propose a special statistical analysis which should be performed separately for the experimental data and for the results of the theoretical computations. In so doing, the random, systematic and total experimental errors are found as functions of separation, taking into account the distribution laws for each error at 95% confidence. Independently, all theoretical errors are combined to obtain the total theoretical error at the same confidence. Finally, the confidence interval for the differences between theoretical and experimental values is obtained as a function of separation. This rigorous approach is applied to two recent experiments on the Casimir effect

  2. A pedagogical approach to the Boltzmann factor through experiments and simulations

    International Nuclear Information System (INIS)

    Battaglia, O R; Bonura, A; Sperandeo-Mineo, R M

    2009-01-01

    The Boltzmann factor is the basis of a huge amount of thermodynamic and statistical physics, both classical and quantum. It governs the behaviour of all systems in nature that are exchanging energy with their environment. To understand why the expression has this specific form involves a deep mathematical analysis, whose flow of logic is hard to see and is not at the level of high school or college students' preparation. We here present some experiments and simulations aimed at directly deriving its mathematical expression and illustrating the fundamental concepts on which it is grounded. Experiments use easily available apparatuses, and simulations are developed in the Net-Logo environment that, besides having a user-friendly interface, allows an easy interaction with the algorithm. The approach supplies pedagogical support for the introduction of the Boltzmann factor at the undergraduate level to students without a background in statistical mechanics.

  3. Advanced approach to the analysis of a series of in-situ nuclear forward scattering experiments

    International Nuclear Information System (INIS)

    Vrba, Vlastimil; Procházka, Vít; Smrčka, David; Miglierini, Marcel

    2017-01-01

    This study introduces a sequential fitting procedure as a specific approach to nuclear forward scattering (NFS) data evaluation. Principles and usage of this advanced evaluation method are described in details and its utilization is demonstrated on NFS in-situ investigations of fast processes. Such experiments frequently consist of hundreds of time spectra which need to be evaluated. The introduced procedure allows the analysis of these experiments and significantly decreases the time needed for the data evaluation. The key contributions of the study are the sequential use of the output fitting parameters of a previous data set as the input parameters for the next data set and the model suitability crosscheck option of applying the procedure in ascending and descending directions of the data sets. Described fitting methodology is beneficial for checking of model validity and reliability of obtained results.

  4. A pedagogical approach to the Boltzmann factor through experiments and simulations

    Energy Technology Data Exchange (ETDEWEB)

    Battaglia, O R; Bonura, A; Sperandeo-Mineo, R M [University of Palermo Physics Education Research Group, Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo (Italy)], E-mail: sperandeo@difter.unipa.it

    2009-09-15

    The Boltzmann factor is the basis of a huge amount of thermodynamic and statistical physics, both classical and quantum. It governs the behaviour of all systems in nature that are exchanging energy with their environment. To understand why the expression has this specific form involves a deep mathematical analysis, whose flow of logic is hard to see and is not at the level of high school or college students' preparation. We here present some experiments and simulations aimed at directly deriving its mathematical expression and illustrating the fundamental concepts on which it is grounded. Experiments use easily available apparatuses, and simulations are developed in the Net-Logo environment that, besides having a user-friendly interface, allows an easy interaction with the algorithm. The approach supplies pedagogical support for the introduction of the Boltzmann factor at the undergraduate level to students without a background in statistical mechanics.

  5. Use of ethnographic approaches to the study of health experiences in relation to natural landscapes.

    Science.gov (United States)

    O'Brien, Liz; Varley, Pete

    2012-11-01

    This paper discusses the use of ethnographic approaches to explore how engagement with natural landscapes might benefit people's health. Drawing on a selected review of empirical research we identified 30 relevant research papers that utilised qualitative methods to explore health issues and engagement with nature. Three examples of 'alternative' - i.e. non-mainstream qualitative approaches - are used to illustrate how different methods can be used to explore people's experiences of engaging with nature for health. While quantitative methods are dominant in health research, qualitative approaches are becoming more widely used. Approaches such as autoethnography can add value to nature and health studies by providing opportunities for researchers to be self-critical of their role as a researcher. Accompanied visits and visual ethnography can afford the researcher rich data about bodily movement, facial expressions and journeys, as well as dialogues associated with the meanings of nature for health. The paper concludes by suggesting that ethnographic methods can provide useful and important insights into why people engage with the natural environment and the range of health benefits they may gain from contact with nature.

  6. Laparoscopic pancreaticoduodenectomy via a reverse-''V'' approach with four ports: initial experience and perioperative outcomes.

    Science.gov (United States)

    Liu, Zhao; Yu, Mu-Chuan; Zhao, Rui; Liu, Yan-Feng; Zeng, Jian-Ping; Wang, Xian-Qiang; Tan, Jing-Wang

    2015-02-07

    To evaluate the feasibility, safety, and efficacy of laparoscopic pancreaticoduodenectomy (LPD) using a reverse-"V" approach with four ports. This is a retrospective study of selected patients who underwent LPD at our center between April 2011 and April 2012. The following data were collected and reviewed: patient characteristics, tumor histology, surgical outcome, resection margins, morbidity, and mortality. All patients were thoroughly evaluated preoperatively by complete hematologic investigations, triple-phase helical computed tomography, upper gastrointestinal endoscopy, and biopsy of ampullary lesions (when present). Magnetic resonance cholangiopancreatography was performed for doubtful cases of lower common bile duct lesions. There was no perioperative mortality. LPD was performed with tumor-free margins in all patients, including patients with pancreatic ductal adenocarcinoma (n = 6), ampullary carcinoma (n = 6), intra-ductal papillary mucinous neoplasm (n = 2), pancreatic cystadenocarcinoma (n = 2), pancreatic head adenocarcinoma (n = 3), and bile duct cancer (n = 2). The mean patient age was 65 years (range, 42-75 years). The median blood loss was 240 mL, and the mean operative time was 368 min. LPD using a reverse-"V" approach can be performed safely and yields good results in elective patients. Our preliminary experience showed that LDP can be performed via a reverse-"V" approach. This approach can be used to treat localized malignant lesions irrespective of histopathology.

  7. Implementation of laparoscopic approach in colorectal surgery - a single center's experience.

    Science.gov (United States)

    Kwiatkowski, Andrzej P; Stępińska, Gabriela; Stanowski, Edward; Paśnik, Krzysztof

    2018-03-01

    Implementation of the laparoscopic approach in colorectal surgery has not happened as rapidly as in cholecystectomy, because of concerns about oncological safety. The results of controlled trials in multiple centers showed the method to be safe. Consequently, surgeons decided to try the approach with colorectal surgery. This process, in our clinic, began in earnest about four years ago. To analyze and present the clinical outcomes of applying the laparoscopic approach to colorectal surgery in a single center. We retrospectively identified patients from a hospital database who underwent colorectal surgery - laparoscopic and open - between 2013 and 2016. Our focus was on laparoscopic cases. Study points included operative time, duration of the hospital stay, postoperative mortality and rates of complications, conversion, reoperation and readmission. Of 534 cases considered, the results showed that the relation between open and laparoscopic procedures had reversed, in favor of the latter method (2013: open: 82% vs. laparoscopic: 18%; 2016: open: 22.4% vs. laparoscopic: 77.6%). The most commonly performed procedure was right hemicolectomy. The total complication rate was 22%. The total rate of conversion to open surgery was 9.3%. The postoperative mortality rate was 3%. Use of the laparoscopic approach in colorectal surgery has increased in recent years world-wide - including in Poland - but the technique is still underused. Rapid implementation of the miniinvasive method in colorectal surgery, in centers with previous laparoscopic experience, is not only safe and feasible, but also highly recommended.

  8. Application of Best Estimate Approach for Modelling of QUENCH-03 and QUENCH-06 Experiments

    Directory of Open Access Journals (Sweden)

    Tadas Kaliatka

    2016-04-01

    In this article, the QUENCH-03 and QUENCH-06 experiments are modelled using ASTEC and RELAP/SCDAPSIM codes. For the uncertainty and sensitivity analysis, SUSA3.5 and SUNSET tools were used. The article demonstrates that applying the best estimate approach, it is possible to develop basic QUENCH input deck and to develop the two sets of input parameters, covering maximal and minimal ranges of uncertainties. These allow simulating different (but with the same nature tests, receiving calculation results with the evaluated range of uncertainties.

  9. A systems approach framework for the transition to sustainable development: Potential value based on coastal experiments

    DEFF Research Database (Denmark)

    Hopkins, Tom S.; Bailly, Denis; Elmgren, Ragnar

    2012-01-01

    This article explores the value of the Systems Approach Framework (SAF) as a tool for the transition to sustainable development in coastal zone systems, based on 18 study sites in Europe, where the SAF was developed and tested. The knowledge gained from these experiments concerns the practical......-dependent and system-independent problems, and the inclusion of non-market evaluations. It also develops a real partnership among research, management, and stakeholders to establish a quantitative basis for collaborative decision making. Furthermore, the article argues that the transition to sustainable development...

  10. A wave optics approach to the theory of the Michelson-Morley experiment

    Science.gov (United States)

    Smid, Thomas

    2017-11-01

    A consistent classical wave optics approach to the theory of the Michelson-Morley experiment shows that the original theory as applied by Michelson and Morley and others does not calculate the optical paths of the two beams correctly, primarily because of incorrectly assuming a right angle reflection in the instrument’s reference frame for the transverse beam, but also because of the incorrect assumption of aberration for the wave fronts. The theory presented in this work proves the expected variation of the phase difference when rotating the interferometer to be more than twice as large and also strongly asymmetrical around the zero line.

  11. Art and architecture as experience: an alternative approach to bridging art history and the neurosciences.

    Science.gov (United States)

    Zschocke, Nina

    2012-08-01

    In 1972, Michael Baxandal characterizes the processes responsible for the cultural relativism of art experience as highly complex and unknown in their physiological detail. While art history still shows considerable interest in the brain sciences forty years later, most cross-disciplinary studies today are referring to the neurosciences in an attempt to seek scientific legitimization of variations of a generalized and largely deterministic model of perception, reducing interaction between a work of art and its observers to a set of biological automatisms. I will challenge such an approach and take up art theory's interest in the historico-cultural and situational dimensions of art experience. Looking at two examples of large-scale installation and sculptural post-war American art, I will explore instable perceptions of depth and changing experiences of space that indicate complex interactions between perceptual and higher cognitive processes. The argument will draw on recent theories describing neuronal processes underlying multistable phenomena, eye movement, visual attention and decision-making. As I will show a large number of neuroscientific studies provide theoretical models that help us analyse not the anthropological constants but the influence of cultural, individual and situational variables on aesthetic experience.

  12. Experiences of parents of children with special needs at school entry: a mixed method approach.

    Science.gov (United States)

    Siddiqua, A; Janus, M

    2017-07-01

    The transition from pre-school to kindergarten can be complex for children who need special assistance due to mental or physical disabilities (children with 'special needs'). We used a convergent mixed method approach to explore parents' experiences with service provision as their children transitioned to school. Parents (including one grandparent) of 37 children aged 4 to 6 years completed measures assessing their perceptions of and satisfaction with services. Semi-structured interviews were also conducted with 10 parents to understand their experience with services. Post transition, parents reported lower perceptions of services and decreased satisfaction than pre-transition. The following themes emerged from the qualitative data: qualities of services and service providers, communication and information transfer, parent advocacy, uncertainty about services, and contrasts and contradictions in satisfaction. The qualitative findings indicate that parents were both satisfied and concerned with aspects of the post-transition service provision. While the quantitative results suggested that parents' experience with services became less positive after their children entered school, the qualitative findings illustrated the variability in parents' experiences and components of service provision that require improvements to facilitate a successful school entry. © 2017 John Wiley & Sons Ltd.

  13. [Threats to Identity: A Grounded Theory Approach on Student Nurses' Experience of Incivility during Clinical Placement].

    Science.gov (United States)

    Kang, Jiyeon; Jeong, Yeon Jin; Kong, Kyoung Ran

    2018-02-01

    This qualitative study aimed to explore the experience of incivility among nursing students. Sixteen nursing students who had experienced incivility during their clinical placement were invited for one-on-one interviews until the point of theoretical saturation. The grounded theory approach of Corbin and Strauss was adopted to analyze transcribed interview contents. Incivility occurred in the context of a hierarchical organizational culture, due to nursing students' position as outsiders, non-systematic clinical education, and poor nursing work environment. The experience of incivility was identified as "being mistreated as a marginal person," and nursing students responded to this phenomenon in the following three steps: reality shock, passive action, and submissive acceptance. This process caused students to lose self-esteem and undergo role conflict. Furthermore, nursing students' experience of incivility could eventually lead to workplace bullying in nurses. The results of this study suggest that nursing students' experience of incivility can be a process that threatens their identity. It is necessary to develop educational programs and provide appropriate counseling services so that nursing students can actively cope with the incivility. In addition, institutional plans are needed to ensure safe and supportive clinical learning environments. © 2018 Korean Society of Nursing Science.

  14. Systematic approach to training. Experiences from the training activities of regulatory body personnel in STUK

    International Nuclear Information System (INIS)

    Aro, I.

    1998-04-01

    The report describes the experiences obtained of a training programme for nuclear power plant inspectors arranged in the 90's by the Radiation and Nuclear Safety Authority of Finland (STUK). In the implementation of the programme, a systematic method was used to analyse the training needs, to plan, develop and implement the training programme as well as to assess the programme's implementation and results. The method used, 'SAT Ae Systematic Approach to Training', is presented in 'Nuclear Power Plant Personnel Training and its Evaluation, A Guidebook', IAEA Technical Report Series No. 380, which is a publication of the International Atomic Energy Agency. It is recommended that this method be applied in the planning and implementation of nuclear power plant personnel training. The application of the method as a tool for developing the qualifications of nuclear power plant inspectors shows that the method is well suited for use in Finland. Until the 90's, STUK had no systematic approach to training activities. Some training was arranged internally, but training in most respects meant participation in external training events and international seminars. A more systematic approach was adopted in the early 90's. The main goal was to define basic competence profiles for inspectors working in different fields and to provide an internal basic training programme not available externally. The development of the training activities called for a profound renewal of the training function to ensure a systematic approach and high quality. The experiences gained in STUK are useful in co-operation with Eastern and Central European regulatory bodies; they can be utilized when the qualifications of personnel who carry out inspections are developed. This will extensively contribute to the safety of nuclear power plants. (orig.)

  15. Systematic approach to training. Experiences from the training activities of regulatory body personnel in STUK

    Energy Technology Data Exchange (ETDEWEB)

    Aro, I.

    1998-04-01

    The report describes the experiences obtained of a training programme for nuclear power plant inspectors arranged in the 90`s by the Radiation and Nuclear Safety Authority of Finland (STUK). In the implementation of the programme, a systematic method was used to analyse the training needs, to plan, develop and implement the training programme as well as to assess the programme`s implementation and results. The method used, `SAT Ae Systematic Approach to Training`, is presented in `Nuclear Power Plant Personnel Training and its Evaluation, A Guidebook`, IAEA Technical Report Series No. 380, which is a publication of the International Atomic Energy Agency. It is recommended that this method be applied in the planning and implementation of nuclear power plant personnel training. The application of the method as a tool for developing the qualifications of nuclear power plant inspectors shows that the method is well suited for use in Finland. Until the 90`s, STUK had no systematic approach to training activities. Some training was arranged internally, but training in most respects meant participation in external training events and international seminars. A more systematic approach was adopted in the early 90`s. The main goal was to define basic competence profiles for inspectors working in different fields and to provide an internal basic training programme not available externally. The development of the training activities called for a profound renewal of the training function to ensure a systematic approach and high quality. The experiences gained in STUK are useful in co-operation with Eastern and Central European regulatory bodies; they can be utilized when the qualifications of personnel who carry out inspections are developed. This will extensively contribute to the safety of nuclear power plants. (orig.). 2 refs.

  16. User Centric Job Monitoring – a redesign and novel approach in the STAR experiment

    International Nuclear Information System (INIS)

    Arkhipkin, D; Lauret, J; Zulkarneeva, Y

    2014-01-01

    User Centric Monitoring (or UCM) has been a long awaited feature in STAR, whereas programs, workflows and system 'events' could be logged, broadcast and later analyzed. UCM allows to collect and filter available job monitoring information from various resources and present it to users in a user-centric view rather than an administrative-centric point of view. The first attempt and implementation of 'a' UCM approach was made in STAR 2004 using a log4cxx plug-in back-end and then further evolved with an attempt to push toward a scalable database back-end (2006) and finally using a Web-Service approach (2010, CSW4DB SBIR). The latest showed to be incomplete and not addressing the evolving needs of the experiment where streamlined messages for online (data acquisition) purposes as well as the continuous support for the data mining needs and event analysis need to coexists and unified in a seamless approach. The code also revealed to be hardly maintainable. This paper presents the next evolutionary step of the UCM toolkit, a redesign and redirection of our latest attempt acknowledging and integrating recent technologies and a simpler, maintainable and yet scalable manner. The extended version of the job logging package is built upon three-tier approach based on Task, Job and Event, and features a Web-Service based logging API, a responsive AJAX-powered user interface, and a database back-end relying on MongoDB, which is uniquely suited for STAR needs. In addition, we present details of integration of this logging package with the STAR offline and online software frameworks. Leveraging on the reported experience and work from the ATLAS and CMS experience on using the ESPER engine, we discuss and show how such approach has been implemented in STAR for meta-data event triggering stream processing and filtering. An ESPER based solution seems to fit well into the online data acquisition system where many systems are monitored.

  17. Uniformization of elliptic curves

    OpenAIRE

    Ülkem, Özge; Ulkem, Ozge

    2015-01-01

    Every elliptic curve E defined over C is analytically isomorphic to C*=qZ for some q ∊ C*. Similarly, Tate has shown that if E is defined over a p-adic field K, then E is analytically isomorphic to K*=qZ for some q ∊ K . Further the isomorphism E(K) ≅ K*/qZ respects the action of the Galois group GK/K, where K is the algebraic closure of K. I will explain the construction of this isomorphism.

  18. Roc curves for continuous data

    CERN Document Server

    Krzanowski, Wojtek J

    2009-01-01

    Since ROC curves have become ubiquitous in many application areas, the various advances have been scattered across disparate articles and texts. ROC Curves for Continuous Data is the first book solely devoted to the subject, bringing together all the relevant material to provide a clear understanding of how to analyze ROC curves.The fundamental theory of ROC curvesThe book first discusses the relationship between the ROC curve and numerous performance measures and then extends the theory into practice by describing how ROC curves are estimated. Further building on the theory, the authors prese

  19. Gender, Narratives and Intersectionality: can Personal Experience Approaches to Research Contribute to "Undoing Gender"?

    Science.gov (United States)

    Cole, Barbara Ann

    2009-11-01

    This paper examines narrative methodologies as one approach to exploring issues of gender, education and social justice and, particularly, insights into "undoing gender". It furthermore examines the possibilities of exploring gender and its multiple intersections in a range of global and policy contexts through the use of personal experience approaches. The "storying" of lived experience is examined as a means of challenging dominant discourses which can construct and other individuals and groups in relation to many aspects of gender and education. Drawing on intersectionality, as a complex and developing feminist theory, the paper considers ways in which narrative can illuminate often hidden complexities while seeking to avoid generalisations and essentialisms. The difficulties of using narrative in relation to these aims are explored in the light of the warnings of feminist writers such as Michele Fine and bell hooks. The paper briefly considers narrative as both methodology and phenomenon, and finally, drawing on critical discourse analysis, discusses the potential of intersectionality and narrative in relation to undoing gender.

  20. Thinkering through Experiments: Nurturing Transdisciplinary Approaches to the Design of Testing Tools

    Directory of Open Access Journals (Sweden)

    Kathryn B. Francis

    2017-11-01

    Full Text Available In order to assess and understand human behavior, traditional approaches to experimental design incorporate testing tools that are often artificial and devoid of corporeal features. Whilst these offer experimental control in situations in which, methodologically, real behaviors cannot be examined, there is increasing evidence that responses given in these contextually deprived experiments fail to trigger genuine responses. This may result from a lack of consideration regarding the material makeup and associations connected with the fabric of experimental tools. In a two-year collaboration, we began to experiment with the physicality of testing tools using the domain of moral psychology as a case study. This collaboration involved thinkering and prototyping methods that included direct contact and consideration of the materials involved in experimentation. Having explored the embodied nature of morality, we combined approaches from experimental psychology, moral philosophy, design thinking, and computer science to create a new testing tool for simulated moral behavior. Although the testing tool itself generated fruitful results, this paper considers the collaborative methodology through which it was produced as a route to highlight material questions within psychological research.

  1. Computational Design and Discovery of Ni-Based Alloys and Coatings: Thermodynamic Approaches Validated by Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zi-Kui [Pennsylvania State University; Gleeson, Brian [University of Pittsburgh; Shang, Shunli [Pennsylvania State University; Gheno, Thomas [University of Pittsburgh; Lindwall, Greta [Pennsylvania State University; Zhou, Bi-Cheng [Pennsylvania State University; Liu, Xuan [Pennsylvania State University; Ross, Austin [Pennsylvania State University

    2018-04-23

    This project developed computational tools that can complement and support experimental efforts in order to enable discovery and more efficient development of Ni-base structural materials and coatings. The project goal was reached through an integrated computation-predictive and experimental-validation approach, including first-principles calculations, thermodynamic CALPHAD (CALculation of PHAse Diagram), and experimental investigations on compositions relevant to Ni-base superalloys and coatings in terms of oxide layer growth and microstructure stabilities. The developed description included composition ranges typical for coating alloys and, hence, allow for prediction of thermodynamic properties for these material systems. The calculation of phase compositions, phase fraction, and phase stabilities, which are directly related to properties such as ductility and strength, was a valuable contribution, along with the collection of computational tools that are required to meet the increasing demands for strong, ductile and environmentally-protective coatings. Specifically, a suitable thermodynamic description for the Ni-Al-Cr-Co-Si-Hf-Y system was developed for bulk alloy and coating compositions. Experiments were performed to validate and refine the thermodynamics from the CALPHAD modeling approach. Additionally, alloys produced using predictions from the current computational models were studied in terms of their oxidation performance. Finally, results obtained from experiments aided in the development of a thermodynamic modeling automation tool called ESPEI/pycalphad - for more rapid discovery and development of new materials.

  2. Experiences of the individual placement and support approach in persons with severe mental illness.

    Science.gov (United States)

    Areberg, Cecilia; Björkman, Tommy; Bejerholm, Ulrika

    2013-09-01

    Across several research studies comparing the individual placement and support (IPS) approach to traditional vocational services, the approach has achieved employment outcomes superior to comparison conditions. However, to understand the efficacy of IPS, it is equally important to consider what is more or less effective as viewed by the IPS participants. To investigate participants' experiences of IPS participation and their experiences of receiving support from an employment specialist (ES). Interviews were conducted with 17 persons with severe mental illness. The interviews were subjected to qualitative content analysis. The principles of informed consent and the voluntary nature of participation were included as ethical considerations. Participation in IPS was associated with hope, meaning and an individualized support provided by the ES. The skills of the ES facilitated the relationship with the participant and the contact with the labour market. However, to make a change happen, everybody involved in IPS had to contribute. These findings have endorsed the guiding principles of IPS and emphasized the ES's role and skills during IPS as well as the participant's motivation. © 2012 The Authors. Scandinavian Journal of Caring Sciences © 2012 Nordic College of Caring Science.

  3. History’s Inconveniences and the Experiences of Exile: A Phenomenological Approach

    Directory of Open Access Journals (Sweden)

    Bondor George

    2005-06-01

    Full Text Available The first part of this paper identifies and analyzes four European cultural models often taken over by Romanian philosophers in XX-th century: the Rationalist, the Romantic, the Marxist and the Existentialist ones. In order to depict the specific manner that two of these models - the romantic and the existentialist - can be found in Romanian philosophy, I shall discuss a common topic, namely the exile, understood as an „escape from history”. The second part of the paper focuses on a phenomenological approach of exile, clarifying different horizons of meaning of this phenomenon, and analyzing those experiences closely connected with the cultural phenomena of exile. The third part of the paper offers a phenomenological description of the places, instances and experiences of exile in Constantin Noica’s life and work. In this respect, I shall analyze several aspects that define the phenomena of exile as an escape from history: Noica’s personality; the mediating function of the School, of philosophy and of culture; the utopian features of The Paltinis School; the theoretical approaches of the question of history, from the denial of factual history to the construction of a different concept of historicity, which can be ultimately regarded as a metaphysical one.

  4. Dialogic and integrated approach to promote soils at different school levels: a Brazilian experience

    Science.gov (United States)

    Muggler, Cristine Carole

    2017-04-01

    From ancient civilizations to present technological societies, soil is the material and immaterial ground of our existence. Soil is essential to life as are water, air and sun light. Nevertheless, it is overlooked and has its functions and importance not known and recognized by people. In formal education and in most school curricula, soil contents are not approached in the same way and intensity other environmental components are. In its essence, soils are an interdisciplinary subject, crossing over different disciplines. It has a great potential as unifying theme that links and synthesizes different contents and areas of knowledge, especially hard sciences as physics, chemistry and biology. Furthermore, soils are familiar and tangible to everyone, making them a meaningful subject that helps to build an efficient learning process. The challenge remains on how to bring such teaching-learning possibilities to formal education at all levels. Soil education deals with the significance of soil to people. What makes soil meaningful? What are the bases for effective learning about soil? The answers are very much related with subjective perceptions and life experiences carried by each individual. Those dimensions have been considered by the pedagogical approach based on Paulo Freire's socio constructivism which considers social inclusion, knowledge building, horizontal learning and collective action. This approach has been applied within the soil (science) education spaces of the Federal University of Viçosa, Minas Gerais, Brazil, both with university students and basic education pupils. At the university an average of 200 students per semester follow a 60 hours Soil Genesis course. With primary and secondary schools the activities are developed through the Soil Education Programme (PES) of the Earth Sciences Museum. In the classes and activities, materials, methods and learning strategies are developed to stimulate involvement, dialogues and exchange of experiences and

  5. Some genus 3 curves with many points

    NARCIS (Netherlands)

    Auer, R; Top, J; Fieker, C; Kohel, DR

    2002-01-01

    We explain a naive approach towards the problem of finding genus 3 curves C over any given finite field F-q of odd characteristic, with a number of rational points close to the Hasse-Weil-Serre upper bound q+1+3[2rootq]. The method turns out to be successful at least in characteristic 3.

  6. Singular interactions supported by embedded curves

    International Nuclear Information System (INIS)

    Kaynak, Burak Tevfik; Turgut, O Teoman

    2012-01-01

    In this work, singular interactions supported by embedded curves on Riemannian manifolds are discussed from a more direct and physical perspective, via the heat kernel approach. We show that the renormalized problem is well defined, the ground state is finite and the corresponding wavefunction is positive. The renormalization group invariance of the model is also discussed. (paper)

  7. A Probabilistic Framework for Curve Evolution

    DEFF Research Database (Denmark)

    Dahl, Vedrana Andersen

    2017-01-01

    approach include ability to handle textured images, simple generalization to multiple regions, and efficiency in computation. We test our probabilistic framework in combination with parametric (snakes) and geometric (level-sets) curves. The experimental results on composed and natural images demonstrate...

  8. The Enactive Approach to Architectural Experience: A Neurophysiological Perspective on Embodiment, Motivation, and Affordances.

    Science.gov (United States)

    Jelić, Andrea; Tieri, Gaetano; De Matteis, Federico; Babiloni, Fabio; Vecchiato, Giovanni

    2016-01-01

    Over the last few years, the efforts to reveal through neuroscientific lens the relations between the mind, body, and built environment have set a promising direction of using neuroscience for architecture. However, little has been achieved thus far in developing a systematic account that could be employed for interpreting current results and providing a consistent framework for subsequent scientific experimentation. In this context, the enactive perspective is proposed as a guide to studying architectural experience for two key reasons. Firstly, the enactive approach is specifically selected for its capacity to account for the profound connectedness of the organism and the world in an active and dynamic relationship, which is primarily shaped by the features of the body. Thus, particular emphasis is placed on the issues of embodiment and motivational factors as underlying constituents of the body-architecture interactions. Moreover, enactive understanding of the relational coupling between body schema and affordances of architectural spaces singles out the two-way bodily communication between architecture and its inhabitants, which can be also explored in immersive virtual reality settings. Secondly, enactivism has a strong foothold in phenomenological thinking that corresponds to the existing phenomenological discourse in architectural theory and qualitative design approaches. In this way, the enactive approach acknowledges the available common ground between neuroscience and architecture and thus allows a more accurate definition of investigative goals. Accordingly, the outlined model of architectural subject in enactive terms-that is, a model of a human being as embodied, enactive, and situated agent, is proposed as a basis of neuroscientific and phenomenological interpretation of architectural experience.

  9. The enactive approach to architectural experience: a neurophysiological perspective on embodiment, motivation, and affordances

    Directory of Open Access Journals (Sweden)

    Andrea eJelic

    2016-03-01

    Full Text Available Over the last few years, the efforts to reveal through neuroscientific lens the relations between the mind, body, and built environment have set a promising direction of using neuroscience for architecture. However, little has been achieved thus far in developing a systematic account that could be employed for interpreting current results and providing a consistent framework for subsequent scientific experimentation. In this context, the enactive perspective is proposed as a guide to studying architectural experience for two key reasons. Firstly, the enactive approach is specifically selected for its capacity to account for the profound connectedness of the organism and the world in an active and dynamic relationship, which is primarily shaped by the features of the body. Thus, particular emphasis is placed on the issues of embodiment and motivational factors as underlying constituents of the body-architecture interactions. Moreover, enactive understanding of the relational coupling between body schema and affordances of architectural spaces singles out the two-way bodily communication between architecture and its inhabitants, which can be also explored in immersive virtual reality settings. Secondly, enactivism has a strong foothold in phenomenological thinking that corresponds to the existing phenomenological discourse in architectural theory and qualitative design approaches. In this way, the enactive approach acknowledges the available common ground between neuroscience and architecture and thus allows a more accurate definition of investigative goals. Accordingly, the outlined model of architectural subject in enactive terms – that is, a model of a human being as embodied, enactive, and situated agent, is proposed as a basis of neuroscientific and phenomenological interpretation of architectural experience.

  10. Retroauricular Approach for Targeted Cochlear Therapy Experiments in Wistar Albino Rats

    Directory of Open Access Journals (Sweden)

    Selçuk Mülazımoğlu

    2017-06-01

    Full Text Available Background: As the idea of stem cell technology in the treatment of sensorial hearing loss has emerged over the past decades, the need for in vivo models for related experiments has become explicit. One of the most common experimental models for inner ear stem cell delivery experiments is the Wistar albino rat. Aims: To investigate the surgical anatomy of the temporal bone of the Wistar albino rat with respect to the dissection steps, operative techniques and potential pitfalls of surgery. Study Design: Animal experimentation. Methods: Adult Wistar albino rats were operated on via the retroauricular approach under an operation microscope. The anatomy of the temporal bone, the surgical route to the temporal bulla and the inner ear were investigated. Technical details of surgical steps, complications and potential pitfalls during the surgery were noted. Results: The study group consisted of 40 adult Wistar albino rats. The mean times to reach the bulla and to achieve cochleostomy were 4.3 (2-13 min and 7.5 min (3.5-22 min, respectively. The mean width of the facial nerve was 0.84 mm (0.42-1.25 mm. The stapedial artery lay nearly perpendicular to the course of the facial nerve (88-93 °C. There were three major complications: two large cochleostomies and one massive bleed from the stapedial artery. Conclusion: The facial nerve was the key anatomical landmark in locating the bulla. By retrograde tracing of the facial nerve, it was possible to find the bulla ventral (inferior to the main trunk. The facial nerve trunk was the upper limit when drilling the bulla. By dissecting the main trunk of the facial nerve and retracting cranially, a large drilling space could be achieved. Our results suggest that the retroauricular approach is an effective, feasible route for inner ear drug delivery experiments in Wistar albino rats

  11. Capturing the experiences of patients across multiple complex interventions: a meta-qualitative approach.

    Science.gov (United States)

    Webster, Fiona; Christian, Jennifer; Mansfield, Elizabeth; Bhattacharyya, Onil; Hawker, Gillian; Levinson, Wendy; Naglie, Gary; Pham, Thuy-Nga; Rose, Louise; Schull, Michael; Sinha, Samir; Stergiopoulos, Vicky; Upshur, Ross; Wilson, Lynn

    2015-09-08

    The perspectives, needs and preferences of individuals with complex health and social needs can be overlooked in the design of healthcare interventions. This study was designed to provide new insights on patient perspectives drawing from the qualitative evaluation of 5 complex healthcare interventions. Patients and their caregivers were recruited from 5 interventions based in primary, hospital and community care in Ontario, Canada. We included 62 interviews from 44 patients and 18 non-clinical caregivers. Our team analysed the transcripts from 5 distinct projects. This approach to qualitative meta-evaluation identifies common issues described by a diverse group of patients, therefore providing potential insights into systems issues. This study is a secondary analysis of qualitative data; therefore, no outcome measures were identified. We identified 5 broad themes that capture the patients' experience and highlight issues that might not be adequately addressed in complex interventions. In our study, we found that: (1) the emergency department is the unavoidable point of care; (2) patients and caregivers are part of complex and variable family systems; (3) non-medical issues mediate patients' experiences of health and healthcare delivery; (4) the unanticipated consequences of complex healthcare interventions are often the most valuable; and (5) patient experiences are shaped by the healthcare discourses on medically complex patients. Our findings suggest that key assumptions about patients that inform intervention design need to be made explicit in order to build capacity to better understand and support patients with multiple chronic diseases. Across many health systems internationally, multiple models are being implemented simultaneously that may have shared features and target similar patients, and a qualitative meta-evaluation approach, thus offers an opportunity for cumulative learning at a system level in addition to informing intervention design and

  12. A user-orientated approach to provenance capture and representation for in silico experiments, explored within the atmospheric chemistry community.

    Science.gov (United States)

    Martin, Chris J; Haji, Mohammed H; Jimack, Peter K; Pilling, Michael J; Dew, Peter M

    2009-07-13

    We present a novel user-orientated approach to provenance capture and representation for in silico experiments, contrasted against the more systems-orientated approaches that have been typical within the e-Science domain. In our approach, we seek to capture the scientist's reasoning in the form of annotations as an experiment evolves, while using the scientist's terminology in the representation of process provenance. Our user-orientated approach is applied in a case study within the atmospheric chemistry domain: we consider the design, development and evaluation of an electronic laboratory notebook, a provenance capture and storage tool, for iterative model development.

  13. Biosafety capacity building: experiences and challenges from a distance learning approach.

    Science.gov (United States)

    Pertry, Ine; Sabbadini, Silvia; Goormachtig, Sofie; Lokko, Yvonne; Gheysen, Godelieve; Burssens, Sylvia; Mezzetti, Bruno

    2014-01-25

    Biotechnology is revolutionizing industrial and agricultural practice as the number of commercial biotechnology products is increasing each year. Simultaneously, several regulatory approaches are put into place to allow technological advancement while preserving public health and the environment. Developing and/or emerging countries often face major barriers to access biotechnologies and biotechnology derived products as they frequently lack the institutional capacities and professional competence in exercising regulatory oversight. To address this need, intensive biosafety capacity building is required. Different training approaches can be used to train individuals in biosafety ranging from long-term leading to a postgraduate certificate or a Masters degree, to short term courses. In this paper, we discuss the applicability of a different approach to biosafety capacity building based on a distance e-learning system, the UNIDO e-Biosafety program that has been annually organized at the Marche Polytechnic University (MPU) in Italy and Ghent University (UGent) in Belgium since 2006. Even though there are some challenges, we can conclude based on our experience that distance learning in combination with on-campus tuition is amendable for biosafety capacity building. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  14. Metabolic Flux Analysis in Isotope Labeling Experiments Using the Adjoint Approach.

    Science.gov (United States)

    Mottelet, Stephane; Gaullier, Gil; Sadaka, Georges

    2017-01-01

    Comprehension of metabolic pathways is considerably enhanced by metabolic flux analysis (MFA-ILE) in isotope labeling experiments. The balance equations are given by hundreds of algebraic (stationary MFA) or ordinary differential equations (nonstationary MFA), and reducing the number of operations is therefore a crucial part of reducing the computation cost. The main bottleneck for deterministic algorithms is the computation of derivatives, particularly for nonstationary MFA. In this article, we explain how the overall identification process may be speeded up by using the adjoint approach to compute the gradient of the residual sum of squares. The proposed approach shows significant improvements in terms of complexity and computation time when it is compared with the usual (direct) approach. Numerical results are obtained for the central metabolic pathways of Escherichia coli and are validated against reference software in the stationary case. The methods and algorithms described in this paper are included in the sysmetab software package distributed under an Open Source license at http://forge.scilab.org/index.php/p/sysmetab/.

  15. Single-port laparoscopic approach of the left liver: initial experience.

    Science.gov (United States)

    Camps Lasa, Judith; Cugat Andorrà, Esteban; Herrero Fonollosa, Eric; García Domingo, María Isabel; Sánchez Martínez, Raquel; Vargas Pierola, Harold; Rodríguez Campos, Aurora

    2014-11-01

    New technological advances have enabled the development of single-port laparoscopic surgery. This approach began with cholecystectomy and subsequently with other abdominal surgeries. However, few publications on laparoscopic liver surgery have described the use of complete single-port access. We present our initial experience of a single-port laparoscopic hepatectomy. Between May 2012 and December 2013, 5 single-port laparoscopic hepatectomies were performed: one for benign disease and four for colorectal liver metastases. The lesions were approached through a 3-5 cm right supraumbilical incision using a single-port access device. All the lesions were located in hepatic segments II or III. Four left lateral sectorectomies and one left hepatectomy were performed. Median operative time was 135 min. No cases were converted to conventional laparoscopic or open surgery. The oral intake began at 18 h. There were no postoperative complications and no patients required blood transfusion. The median hospital stay was 3 days. The degree of satisfaction was very good in 4 cases and good in one. Patients resumed their normal daily activities at 8 days. Single-port laparoscopic hepatectomy is safe and feasible in selected cases and may reduce surgical aggression and offer better cosmetic results. Comparative studies are needed to determine the real advantages of this approach. Copyright © 2014 AEC. Published by Elsevier Espana. All rights reserved.

  16. Recurrent Pneumonia in Children: A Reasoned Diagnostic Approach and a Single Centre Experience.

    Science.gov (United States)

    Montella, Silvia; Corcione, Adele; Santamaria, Francesca

    2017-01-29

    Recurrent pneumonia (RP), i.e., at least two episodes of pneumonia in one year or three episodes ever with intercritical radiographic clearing of densities, occurs in 7.7%-9% of children with community-acquired pneumonia. In RP, the challenge is to discriminate between children with self-limiting or minor problems, that do not require a diagnostic work-up, and those with an underlying disease. The aim of the current review is to discuss a reasoned diagnostic approach to RP in childhood. Particular emphasis has been placed on which children should undergo a diagnostic work-up and which tests should be performed. A pediatric case series is also presented, in order to document a single centre experience of RP. A management algorithm for the approach to children with RP, based on the evidence from a literature review, is proposed. Like all algorithms, it is not meant to replace clinical judgment, but it should drive physicians to adopt a systematic approach to pediatric RP and provide a useful guide to the clinician.

  17. An innovative approach for planning and execution of pre-experimental runs for Design of Experiments

    Directory of Open Access Journals (Sweden)

    Muhammad Arsalan Farooq

    2016-09-01

    Full Text Available This paper addresses the study of the pre-experimental planning phase of the Design of Experiments (DoE in order to improve the final product quality. The pre-experimental planning phase includes a clear identification of the problem statement, selection of control factors and their respective levels and ranges. To improve production quality based on the DoE a new approach for the pre-experimental planning phase, called Non-Conformity Matrix (NCM, is presented. This article also addresses the key steps of the pre-experimental runs considering a consumer goods manufacturing process. Results of the application for an industrial case show that this methodology can support a clear definition of the problem and also a correct identification of the factor ranges in particular situations. The proposed new approach allows modeling the entire manufacturing system holistically and correctly defining the factor ranges and respective levels for a more effective application of DoE. This new approach can be a useful resource for both research and industrial practitioners who are dedicated to large DoE projects with unknown factor interactions, when the operational levels and ranges are not completely defined.

  18. A Semantic-Based Approach for Preserving Operational Experience of Nuclear Installations

    International Nuclear Information System (INIS)

    Kupriyanov, V.; Kossilov, A.; Maximov, N.; Kupriyanova, I.

    2016-01-01

    Full text: The paper discusses the experience in development of the tools necessary for the first phase of automation of description of explicit technological knowledge—the thematic categorization of text documents on nuclear facility life cycle. In the study the existing thematic index, IAEA INIS was used as a target index due to its fullest provision at the moment by such means for Russian texts, thanks to the Russian multilingual thesaurus INIS as there is a lack of similar tools in Russian national index GRNTI. It is proposed to increase the stability of categorization procedures by using a simple ontological model to establish complex links between the presence of the words. The communication model using simplified standard ISO 15926 concepts is proposed to separate descriptors and their relationship to two types: “intelligent concept” and “physical property”. Experience has shown that to build such a model, it is necessary that the indexing experts marked out manually all descriptors according to their belonging to each category. Based on the experience in implementation of this approach the paper argues that for its implementation, it is necessary to train a new type of specialists, knowledge workers, with new competencies including the concepts described above. (author

  19. The narrative structure as a way to gain insight into peoples' experiences: one methodological approach.

    Science.gov (United States)

    Rejnö, Åsa; Berg, Linda; Danielson, Ella

    2014-09-01

    The narrative method is used in healthcare research, mostly in data collection but also in the analysis. Narrative approaches draw attention to how people tell about and create meaning of experiences. The aim of the article was to examine the narrative structure, the elements in the structure and their function and how these can be used in research to gain insights into experiences. Examples are taken from a material of narratives from a study where next of kin were asked to narrate their experiences of sudden and unexpected death from stroke. The narratives had a clear beginning, midpoint and ending. In the beginning, orientation of the narrated events was given. The narrated events were told to have a turning point constituted of complicating actions that lead to a resolution that solved the narrated event. The narratives were built up by multiple recaps into the narrated events and also consisted of asides - side narratives and flashbacks - events back in time. Use of a narrative structure can contribute with valuable information that might be missed with other analysis. The analysis can be used on its own, as a complement to other narrative analysis or even as a complement to other qualitative analysis. © 2013 Nordic College of Caring Science.

  20. Men's experiences of sexuality after cancer: a material discursive intra-psychic approach.

    Science.gov (United States)

    Gilbert, Emilee; Ussher, Jane M; Perz, Janette; Wong, W K Tim; Hobbs, Kim; Mason, Catherine

    2013-01-01

    Men can experience significant changes to their sexuality following the onset of cancer. However, research on men's sexuality post-cancer has focused almost exclusively on those with prostate and testicular cancer, despite evidence that the diagnosis and treatment for most cancers can impact on men's sexuality. This Australian qualitative study explores the experiences of changes to sexuality for 21 men across a range of cancer types and stages, sexual orientations and relationship contexts. Semi-structured interviews were analysed with theoretical thematic analysis guided by a material discursive intra-psychic approach, recognising the materiality of sexual changes, men's intrapsychic experience of such changes within a relational context and the influence of the discursive construction of masculine sexuality. Material changes included erectile difficulty, decreased desire, and difficulty with orgasm. The use of medical aids to minimise the impact of erectile difficulties was shaped by discursive constructions of 'normal' masculine sexuality. The majority of men reported accepting the changes to their sexuality post-cancer and normalised them as part of the natural ageing process. Men's relationship status and context played a key role managing the changes to their sexuality. We conclude by discussing the implications for clinical practice.

  1. Curved Josephson junction

    International Nuclear Information System (INIS)

    Dobrowolski, Tomasz

    2012-01-01

    The constant curvature one and quasi-one dimensional Josephson junction is considered. On the base of Maxwell equations, the sine–Gordon equation that describes an influence of curvature on the kink motion was obtained. It is showed that the method of geometrical reduction of the sine–Gordon model from three to lower dimensional manifold leads to an identical form of the sine–Gordon equation. - Highlights: ► The research on dynamics of the phase in a curved Josephson junction is performed. ► The geometrical reduction is applied to the sine–Gordon model. ► The results of geometrical reduction and the fundamental research are compared.

  2. Curved-Duct

    Directory of Open Access Journals (Sweden)

    Je Hyun Baekt

    2000-01-01

    Full Text Available A numerical study is conducted on the fully-developed laminar flow of an incompressible viscous fluid in a square duct rotating about a perpendicular axis to the axial direction of the duct. At the straight duct, the rotation produces vortices due to the Coriolis force. Generally two vortex cells are formed and the axial velocity distribution is distorted by the effect of this Coriolis force. When a convective force is weak, two counter-rotating vortices are shown with a quasi-parabolic axial velocity profile for weak rotation rates. As the rotation rate increases, the axial velocity on the vertical centreline of the duct begins to flatten and the location of vorticity center is moved near to wall by the effect of the Coriolis force. When the convective inertia force is strong, a double-vortex secondary flow appears in the transverse planes of the duct for weak rotation rates but as the speed of rotation increases the secondary flow is shown to split into an asymmetric configuration of four counter-rotating vortices. If the rotation rates are increased further, the secondary flow restabilizes to a slightly asymmetric double-vortex configuration. Also, a numerical study is conducted on the laminar flow of an incompressible viscous fluid in a 90°-bend square duct that rotates about axis parallel to the axial direction of the inlet. At a 90°-bend square duct, the feature of flow by the effect of a Coriolis force and a centrifugal force, namely a secondary flow by the centrifugal force in the curved region and the Coriolis force in the downstream region, is shown since the centrifugal force in curved region and the Coriolis force in downstream region are dominant respectively.

  3. Elliptic curves for applications (Tutorial)

    NARCIS (Netherlands)

    Lange, T.; Bernstein, D.J.; Chatterjee, S.

    2011-01-01

    More than 25 years ago, elliptic curves over finite fields were suggested as a group in which the Discrete Logarithm Problem (DLP) can be hard. Since then many researchers have scrutinized the security of the DLP on elliptic curves with the result that for suitably chosen curves only exponential

  4. Titration Curves: Fact and Fiction.

    Science.gov (United States)

    Chamberlain, John

    1997-01-01

    Discusses ways in which datalogging equipment can enable titration curves to be measured accurately and how computing power can be used to predict the shape of curves. Highlights include sources of error, use of spreadsheets to generate titration curves, titration of a weak acid with a strong alkali, dibasic acids, weak acid and weak base, and…

  5. An iterative particle filter approach for coupled hydro-geophysical inversion of a controlled infiltration experiment

    International Nuclear Information System (INIS)

    Manoli, Gabriele; Rossi, Matteo; Pasetto, Damiano; Deiana, Rita; Ferraris, Stefano; Cassiani, Giorgio; Putti, Mario

    2015-01-01

    The modeling of unsaturated groundwater flow is affected by a high degree of uncertainty related to both measurement and model errors. Geophysical methods such as Electrical Resistivity Tomography (ERT) can provide useful indirect information on the hydrological processes occurring in the vadose zone. In this paper, we propose and test an iterated particle filter method to solve the coupled hydrogeophysical inverse problem. We focus on an infiltration test monitored by time-lapse ERT and modeled using Richards equation. The goal is to identify hydrological model parameters from ERT electrical potential measurements. Traditional uncoupled inversion relies on the solution of two sequential inverse problems, the first one applied to the ERT measurements, the second one to Richards equation. This approach does not ensure an accurate quantitative description of the physical state, typically violating mass balance. To avoid one of these two inversions and incorporate in the process more physical simulation constraints, we cast the problem within the framework of a SIR (Sequential Importance Resampling) data assimilation approach that uses a Richards equation solver to model the hydrological dynamics and a forward ERT simulator combined with Archie's law to serve as measurement model. ERT observations are then used to update the state of the system as well as to estimate the model parameters and their posterior distribution. The limitations of the traditional sequential Bayesian approach are investigated and an innovative iterative approach is proposed to estimate the model parameters with high accuracy. The numerical properties of the developed algorithm are verified on both homogeneous and heterogeneous synthetic test cases based on a real-world field experiment

  6. An iterative particle filter approach for coupled hydro-geophysical inversion of a controlled infiltration experiment

    Energy Technology Data Exchange (ETDEWEB)

    Manoli, Gabriele, E-mail: manoli@dmsa.unipd.it [Department of Mathematics, University of Padova, Via Trieste 63, 35121 Padova (Italy); Nicholas School of the Environment, Duke University, Durham, NC 27708 (United States); Rossi, Matteo [Department of Geosciences, University of Padova, Via Gradenigo 6, 35131 Padova (Italy); Pasetto, Damiano [Department of Mathematics, University of Padova, Via Trieste 63, 35121 Padova (Italy); Deiana, Rita [Dipartimento dei Beni Culturali, University of Padova, Piazza Capitaniato 7, 35139 Padova (Italy); Ferraris, Stefano [Interuniversity Department of Regional and Urban Studies and Planning, Politecnico and University of Torino, Viale Mattioli 39, 10125 Torino (Italy); Cassiani, Giorgio [Department of Geosciences, University of Padova, Via Gradenigo 6, 35131 Padova (Italy); Putti, Mario [Department of Mathematics, University of Padova, Via Trieste 63, 35121 Padova (Italy)

    2015-02-15

    The modeling of unsaturated groundwater flow is affected by a high degree of uncertainty related to both measurement and model errors. Geophysical methods such as Electrical Resistivity Tomography (ERT) can provide useful indirect information on the hydrological processes occurring in the vadose zone. In this paper, we propose and test an iterated particle filter method to solve the coupled hydrogeophysical inverse problem. We focus on an infiltration test monitored by time-lapse ERT and modeled using Richards equation. The goal is to identify hydrological model parameters from ERT electrical potential measurements. Traditional uncoupled inversion relies on the solution of two sequential inverse problems, the first one applied to the ERT measurements, the second one to Richards equation. This approach does not ensure an accurate quantitative description of the physical state, typically violating mass balance. To avoid one of these two inversions and incorporate in the process more physical simulation constraints, we cast the problem within the framework of a SIR (Sequential Importance Resampling) data assimilation approach that uses a Richards equation solver to model the hydrological dynamics and a forward ERT simulator combined with Archie's law to serve as measurement model. ERT observations are then used to update the state of the system as well as to estimate the model parameters and their posterior distribution. The limitations of the traditional sequential Bayesian approach are investigated and an innovative iterative approach is proposed to estimate the model parameters with high accuracy. The numerical properties of the developed algorithm are verified on both homogeneous and heterogeneous synthetic test cases based on a real-world field experiment.

  7. Molecular dynamics simulations of the melting curve of NiAl alloy under pressure

    International Nuclear Information System (INIS)

    Zhang, Wenjin; Peng, Yufeng; Liu, Zhongli

    2014-01-01

    The melting curve of B2-NiAl alloy under pressure has been investigated using molecular dynamics technique and the embedded atom method (EAM) potential. The melting temperatures were determined with two approaches, the one-phase and the two-phase methods. The first one simulates a homogeneous melting, while the second one involves a heterogeneous melting of materials. Both approaches reduce the superheating effectively and their results are close to each other at the applied pressures. By fitting the well-known Simon equation to our melting data, we yielded the melting curves for NiAl: 1783(1 + P/9.801) 0.298 (one-phase approach), 1850(1 + P/12.806) 0.357 (two-phase approach). The good agreement of the resulting equation of states and the zero-pressure melting point (calc., 1850 ± 25 K, exp., 1911 K) with experiment proved the correctness of these results. These melting data complemented the absence of experimental high-pressure melting of NiAl. To check the transferability of this EAM potential, we have also predicted the melting curves of pure nickel and pure aluminum. Results show the calculated melting point of Nickel agrees well with experiment at zero pressure, while the melting point of aluminum is slightly higher than experiment

  8. Team approach to manage difficult-to-treat TB cases: Experiences in Europe and beyond

    Directory of Open Access Journals (Sweden)

    L. D’Ambrosio

    2018-03-01

    Full Text Available As recommended by the World Health Organization (WHO, optimal management of MDR-TB cases can be ensured by a multi-speciality consultation body known as ‘TB Consilium’. This body usually includes different medical specialities, competences and perspectives (e.g., clinical expertise both for adults and children; surgical, radiological and public health expertise; psychological background and nursing experience, among others, thus lowering the risk of making mistakes – or managing the patients inappropriately, in order to improve their clinical outcomes.At present, several high MDR-TB burden countries in the different WHO regions (and beyond have introduced TB Consilium-like bodies at the national or subnational level to reach consensus on the best treatment approach for their patients affected by TB.In addition, in countries/settings where a formal system of consultation does not exist, specialized staff from MDR-TB reference centres or international organizations usually spend a considerable amount of their working time responding to phone or e-mail clinical queries on how to manage M/XDR-TB cases.The aim of this manuscript is to describe the different experiences with the TB Consilia both at the international level (European Respiratory Society – ERS/WHO TB Consilium and in some of the countries where this experience operates successfully in Europe and beyond. The Consilium experiences are described around the following topics: (1 history, aims and focus; (2 management and funding; (3 technical functioning and structure; (4 results achieved.In addition a comparative analysis of the TB Consilia in the different countries has been performed. Keywords: MDR-TB, XDR-TB, Clinical management, Drug resistance, Prevention, Consilium

  9. A Journey Between Two Curves

    Directory of Open Access Journals (Sweden)

    Sergey A. Cherkis

    2007-03-01

    Full Text Available A typical solution of an integrable system is described in terms of a holomorphic curve and a line bundle over it. The curve provides the action variables while the time evolution is a linear flow on the curve's Jacobian. Even though the system of Nahm equations is closely related to the Hitchin system, the curves appearing in these two cases have very different nature. The former can be described in terms of some classical scattering problem while the latter provides a solution to some Seiberg-Witten gauge theory. This note identifies the setup in which one can formulate the question of relating the two curves.

  10. How do multi-touchpoint experience affect consumer satisfaction and behavior : a real-time experience tracking approach

    NARCIS (Netherlands)

    Li, J.; Konus, U.; Macdonald, E.K.; Wilson, H.N.; Langerak, F.; Warlop, L.; Muylle, S.

    2015-01-01

    A customer experiences various touchpoints during the shopping trip with a brand, (i.e., traditional advertising, online and WOMs). However, it is still unknown how satisfaction and behavior are affected by customers’ instant touchpoint experiences during the shopping process. Therefore we

  11. Boiling curve in high quality flow boiling

    International Nuclear Information System (INIS)

    Shiralkar, B.S.; Hein, R.A.; Yadigaroglu, G.

    1980-01-01

    The post dry-out heat transfer regime of the flow boiling curve was investigated experimentally for high pressure water at high qualities. The test section was a short round tube located downstream of a hot patch created by a temperature controlled segment of tubing. Results from the experiment showed that the distance from the dryout point has a significant effect on the downstream temperatures and there was no unique boiling curve. The heat transfer coefficients measured sufficiently downstream of the dryout point could be correlated using the Heineman correlation for superheated steam, indicating that the droplet deposition effects could be neglected in this region

  12. Meta-design Approach for Mobile Platforms Supporting Creative Tourism Experiences

    DEFF Research Database (Denmark)

    Tussyadiah, Iis P.

    2013-01-01

    with and interpretations of the local attributes of tourism destinations. The mobile system will integrate the sensory stimuli, the intense contact with cultural nuances and social network, the brand-based reputation, and the creative communities at tourism destinations into the iterative process of perception, conception......This paper conceptualizes the application of meta-design approach in the development of a mobile system supporting creative experiences for tourists. Specifically, for those working in creative industries, adaptive mobile system will facilitate effective tourists' interactions......, and expression of creative ideas among tourists. For destinations trying to highlight their unique characteristics as their value proposition, the development of such system may benefit them from a heightened sense of place due to on-going value co-creation. Individuals will benefit from such system from...

  13. Natural Experiments: An Overview of Methods, Approaches, and Contributions to Public Health Intervention Research.

    Science.gov (United States)

    Craig, Peter; Katikireddi, Srinivasa Vittal; Leyland, Alastair; Popham, Frank

    2017-03-20

    Population health interventions are essential to reduce health inequalities and tackle other public health priorities, but they are not always amenable to experimental manipulation. Natural experiment (NE) approaches are attracting growing interest as a way of providing evidence in such circumstances. One key challenge in evaluating NEs is selective exposure to the intervention. Studies should be based on a clear theoretical understanding of the processes that determine exposure. Even if the observed effects are large and rapidly follow implementation, confidence in attributing these effects to the intervention can be improved by carefully considering alternative explanations. Causal inference can be strengthened by including additional design features alongside the principal method of effect estimation. NE studies often rely on existing (including routinely collected) data. Investment in such data sources and the infrastructure for linking exposure and outcome data is essential if the potential for such studies to inform decision making is to be realized.

  14. Unpacking buyer-seller differences in valuation from experience: A cognitive modeling approach.

    Science.gov (United States)

    Pachur, Thorsten; Scheibehenne, Benjamin

    2017-12-01

    People often indicate a higher price for an object when they own it (i.e., as sellers) than when they do not (i.e., as buyers)-a phenomenon known as the endowment effect. We develop a cognitive modeling approach to formalize, disentangle, and compare alternative psychological accounts (e.g., loss aversion, loss attention, strategic misrepresentation) of such buyer-seller differences in pricing decisions of monetary lotteries. To also be able to test possible buyer-seller differences in memory and learning, we study pricing decisions from experience, obtained with the sampling paradigm, where people learn about a lottery's payoff distribution from sequential sampling. We first formalize different accounts as models within three computational frameworks (reinforcement learning, instance-based learning theory, and cumulative prospect theory), and then fit the models to empirical selling and buying prices. In Study 1 (a reanalysis of published data with hypothetical decisions), models assuming buyer-seller differences in response bias (implementing a strategic-misrepresentation account) performed best; models assuming buyer-seller differences in choice sensitivity or memory (implementing a loss-attention account) generally fared worst. In a new experiment involving incentivized decisions (Study 2), models assuming buyer-seller differences in both outcome sensitivity (as proposed by a loss-aversion account) and response bias performed best. In both Study 1 and 2, the models implemented in cumulative prospect theory performed best. Model recovery studies validated our cognitive modeling approach, showing that the models can be distinguished rather well. In summary, our analysis supports a loss-aversion account of the endowment effect, but also reveals a substantial contribution of simple response bias.

  15. Asian Americans and Cancer Clinical Trials: A Mixed-Methods Approach to Understanding Awareness and Experience

    Science.gov (United States)

    Paterniti, Debora A.; Chen, Moon S.; Chiechi, Christine; Beckett, Laurel A.; Horan, Nora; Turrell, Corinne; Smith, Ligaya; Morain, Claudia; Montell, Lisa; Gonzalez, Jose Luis; Davis, Sharon; Lara, Primo N.

    2006-01-01

    Cancer clinical trials have been based on low accrual rates. Barriers to recruitment of minority populations affect the generalizability and impact of trial findings for those populations. The authors undertook a mixed-methods approach to understanding levels of awareness and experiences with cancer clinical trials. A survey was administered to new cancer patients and their caretakers (family, close friends, or other social support) at outpatient oncology clinics. Field observations of the trial accrual process also were conducted by employing the grounded theory approach in qualitative methods. Comparison of survey results for Asian-American respondents and non-Asian respondents indicated that Asians were less likely to have heard the term “clinical trial” and were more likely to define a clinical trial as “an experiment” or “a test procedure in a clinic” than non-Asians. Asians were more likely to have employer-based insurance and to report understanding issues related to cost reimbursement. Asians were less likely to have been involved in or to know someone in a trial and reported less willingness than white respondents to consider trial participation. Qualitative observations suggested that Asians who presented for a potential trial were interested in the availability of a novel cancer therapy but were not eligible for available trials. Multiple strategies will be necessary to enhance awareness of and experience with accrual to cancer clinical trials for Asians, including richer understanding and increased involvement of Asians in cancer clinical trials and greater attention to the location and diversity of the Asian population in structuring study centers and evaluating trial results. PMID:16247795

  16. Soil Water Retention Curve

    Science.gov (United States)

    Johnson, L. E.; Kim, J.; Cifelli, R.; Chandra, C. V.

    2016-12-01

    Potential water retention, S, is one of parameters commonly used in hydrologic modeling for soil moisture accounting. Physically, S indicates total amount of water which can be stored in soil and is expressed in units of depth. S can be represented as a change of soil moisture content and in this context is commonly used to estimate direct runoff, especially in the Soil Conservation Service (SCS) curve number (CN) method. Generally, the lumped and the distributed hydrologic models can easily use the SCS-CN method to estimate direct runoff. Changes in potential water retention have been used in previous SCS-CN studies; however, these studies have focused on long-term hydrologic simulations where S is allowed to vary at the daily time scale. While useful for hydrologic events that span multiple days, the resolution is too coarse for short-term applications such as flash flood events where S may not recover its full potential. In this study, a new method for estimating a time-variable potential water retention at hourly time-scales is presented. The methodology is applied for the Napa River basin, California. The streamflow gage at St Helena, located in the upper reaches of the basin, is used as the control gage site to evaluate the model performance as it is has minimal influences by reservoirs and diversions. Rainfall events from 2011 to 2012 are used for estimating the event-based SCS CN to transfer to S. As a result, we have derived the potential water retention curve and it is classified into three sections depending on the relative change in S. The first is a negative slope section arising from the difference in the rate of moving water through the soil column, the second is a zero change section representing the initial recovery the potential water retention, and the third is a positive change section representing the full recovery of the potential water retention. Also, we found that the soil water moving has traffic jam within 24 hours after finished first

  17. Shared-Book Experience Using Science-Themed Books to Develop Scientific Literacy: An Interactive Approach with Struggling Readers

    Science.gov (United States)

    Chung, Mi-Hyun; Keckler, Barbara

    2016-01-01

    This paper will explain what a reading teacher learned from working with a group of first-grade struggling readers in a series of shared-book experience classes. The shared-book experience approach used a variety of science-themed books that were aligned with the first-grade curriculum and appropriate for beginning readers. Considering the…

  18. Flipping and Still Learning: Experiences of a Flipped Classroom Approach for a Third-Year Undergraduate Human Geography Course

    Science.gov (United States)

    Graham, Marnie; McLean, Jessica; Read, Alexander; Suchet-Pearson, Sandie; Viner, Venessa

    2017-01-01

    The flipped classroom approach, a form of blended learning, is currently popular in education praxis. Initial reports on the flipped classroom include that it offers opportunities to increase student engagement and build meaningful learning and teaching experiences. In this article, we analyse teacher and student experiences of a trial flipped…

  19. Compact Hilbert Curve Index Algorithm Based on Gray Code

    Directory of Open Access Journals (Sweden)

    CAO Xuefeng

    2016-12-01

    Full Text Available Hilbert curve has best clustering in various kinds of space filling curves, and has been used as an important tools in discrete global grid spatial index design field. But there are lots of redundancies in the standard Hilbert curve index when the data set has large differences between dimensions. In this paper, the construction features of Hilbert curve is analyzed based on Gray code, and then the compact Hilbert curve index algorithm is put forward, in which the redundancy problem has been avoided while Hilbert curve clustering preserved. Finally, experiment results shows that the compact Hilbert curve index outperforms the standard Hilbert index, their 1 computational complexity is nearly equivalent, but the real data set test shows the coding time and storage space decrease 40%, the speedup ratio of sorting speed is nearly 4.3.

  20. Farmer preference for improved corn seeds in Chiapas, Mexico: A choice experiment approach

    International Nuclear Information System (INIS)

    Sánchez-Toledano, Blanca I.; Kallas, Zein; Gil-Roig, José M.

    2017-01-01

    Appropriate technologies must be developed for adoption of improved seeds based on the farmers’ preferences and needs. Our research identified the farmers’ willingness to pay (WTP) as a key determinant for selecting the improved varieties of maize seeds and landraces in Chiapas, Mexico. This work also analyzed the farmers’ observed heterogeneity on the basis of their socio-economic characteristics. Data were collected using a semi-structured questionnaire from 200 farmers. A proportional choice experiment approach was applied using a proportional choice variable, where farmers were asked to state the percentage of preference for different alternative varieties in a choice set. The generalized multinomial logit model in WTP-space approach was used. The results suggest that the improved seed varieties are preferred over the Creole alternatives, thereby ensuring higher yields, resistance to diseases, and larger ear size. For the preference heterogeneity analyses, a latent class model was applied. Three types of farmers were identified: innovators (60.5%), transition farmers (29.4%), and conservative farmers (10%). An understanding of farmers’ preferences is useful in designing agricultural policies and creati

  1. Farmer preference for improved corn seeds in Chiapas, Mexico: A choice experiment approach

    Directory of Open Access Journals (Sweden)

    Blanca I. Sánchez-Toledano

    2017-12-01

    Full Text Available Appropriate technologies must be developed for adoption of improved seeds based on the farmers’ preferences and needs. Our research identified the farmers’ willingness to pay (WTP as a key determinant for selecting the improved varieties of maize seeds and landraces in Chiapas, Mexico. This work also analyzed the farmers’ observed heterogeneity on the basis of their socio-economic characteristics. Data were collected using a semi-structured questionnaire from 200 farmers. A proportional choice experiment approach was applied using a proportional choice variable, where farmers were asked to state the percentage of preference for different alternative varieties in a choice set. The generalized multinomial logit model in WTP-space approach was used. The results suggest that the improved seed varieties are preferred over the Creole alternatives, thereby ensuring higher yields, resistance to diseases, and larger ear size. For the preference heterogeneity analyses, a latent class model was applied. Three types of farmers were identified: innovators (60.5%, transition farmers (29.4%, and conservative farmers (10%. An understanding of farmers’ preferences is useful in designing agricultural policies and creating pricing and marketing strategies for the dissemination of quality seeds.

  2. Farmer preference for improved corn seeds in Chiapas, Mexico: A choice experiment approach

    Energy Technology Data Exchange (ETDEWEB)

    Sánchez-Toledano, Blanca I.; Kallas, Zein; Gil-Roig, José M.

    2017-07-01

    Appropriate technologies must be developed for adoption of improved seeds based on the farmers’ preferences and needs. Our research identified the farmers’ willingness to pay (WTP) as a key determinant for selecting the improved varieties of maize seeds and landraces in Chiapas, Mexico. This work also analyzed the farmers’ observed heterogeneity on the basis of their socio-economic characteristics. Data were collected using a semi-structured questionnaire from 200 farmers. A proportional choice experiment approach was applied using a proportional choice variable, where farmers were asked to state the percentage of preference for different alternative varieties in a choice set. The generalized multinomial logit model in WTP-space approach was used. The results suggest that the improved seed varieties are preferred over the Creole alternatives, thereby ensuring higher yields, resistance to diseases, and larger ear size. For the preference heterogeneity analyses, a latent class model was applied. Three types of farmers were identified: innovators (60.5%), transition farmers (29.4%), and conservative farmers (10%). An understanding of farmers’ preferences is useful in designing agricultural policies and creati.

  3. Experience in the use of systematic approach to training (SAT) for nuclear power plant personnel

    International Nuclear Information System (INIS)

    1998-12-01

    One of the essential requirements for safe and reliable nuclear power plant operation and maintenance is the availability of competent personnel, and thus systematic approach to training (SAT) is recognized world-wide. Many countries have applied and implemented the use of SAT in their training systems as demonstrated by the results of the IAEA World Survey on Nuclear Power Plant Personnel Training. This report complements two IAEA publications, the Guidebook on Nuclear Power Plant Personnel and its Evaluation (Technical Reports Series No. 380) and the IAEA World Survey of Nuclear Power Plant Personnel Training (IAEA-TECDOC-1063). It provides a detailed overview and analysis of the experience gained worldwide on the introduction and application of SAT, including the reasons why SAT was introduced and lessons learned. The technical document will be of use for nuclear power plant managers and supervisors and all those responsible for training of personnel. The report was initiated by the International Working Group at a Technical Committee Meeting. Experiences gained from the application of SAT in the following Member States are included: Armenia, Bulgaria, Canada, China, Czech Republic, Finland, France, Germany, Hungary, India, Kazakhstan, Lithuania, Mexico, Romania, Russian Federation, Slovenia, Slovakia, Spain, Sweden, Ukraine, United Kingdom and United States of America

  4. Experience in the use of systematic approach to training (SAT) for nuclear power plant personnel

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-01

    One of the essential requirements for safe and reliable nuclear power plant operation and maintenance is the availability of competent personnel, and thus systematic approach to training (SAT) is recognized world-wide. Many countries have applied and implemented the use of SAT in their training systems as demonstrated by the results of the IAEA World Survey on Nuclear Power Plant Personnel Training. This report complements two IAEA publications, the Guidebook on Nuclear Power Plant Personnel and its Evaluation (Technical Reports Series No. 380) and the IAEA World Survey of Nuclear Power Plant Personnel Training (IAEA-TECDOC-1063). It provides a detailed overview and analysis of the experience gained worldwide on the introduction and application of SAT, including the reasons why SAT was introduced and lessons learned. The technical document will be of use for nuclear power plant managers and supervisors and all those responsible for training of personnel. The report was initiated by the International Working Group at a Technical Committee Meeting. Experiences gained from the application of SAT in the following Member States are included: Armenia, Bulgaria, Canada, China, Czech Republic, Finland, France, Germany, Hungary, India, Kazakhstan, Lithuania, Mexico, Romania, Russian Federation, Slovenia, Slovakia, Spain, Sweden, Ukraine, United Kingdom and United States of America. Refs, figs, tabs

  5. Valuing health risk in agriculture: a choice experiment approach to pesticide use in China.

    Science.gov (United States)

    Jin, Jianjun; Wang, Wenyu; He, Rui; Gong, Haozhou

    2017-07-01

    This paper presents a choice experiment approach to investigate farmers' valuations for health risk changes associated with pesticide use in Anqiu County, China. An empirical comparison on the disparity between farmers' willingness to pay (WTP) for a health risk reduction and willingness to accept (WTA) for the same risk increase is also conducted. Respondents were randomly assigned into the WTP group or the WTA group. Four attributes (health consequence, baseline risk, risk change size, and price) were identified and included. The results show that cancer consequence due to pesticide use decreases the utility of the farmer. A higher baseline risk has a higher WTP to reduce the risk and a higher probability of receiving compensation. If the health risk change size is bigger, it will result in a higher WTP and higher compensation. Household income, education, and age have significant and positive impacts on farmers' WTP. Farmers who are more educated or female are more likely to accept the compensation scheme if health risks increase. The marginal WTA for the same risk change is about two times higher than the marginal WTP. The findings of this study can contribute to the literature comparing people's WTP and WTA in a discrete choice experiment on valuing health risk changes associated with pesticide use.

  6. Elderly women's experiences of living with fall risk in a fragile body: a reflective lifeworld approach.

    Science.gov (United States)

    Berlin Hallrup, Leena; Albertsson, Daniel; Bengtsson Tops, Anita; Dahlberg, Karin; Grahn, Birgitta

    2009-07-01

    The purpose of this qualitative study was to explore the lived experience of fall risk from a lifeworld perspective in elderly women with previous fragility fractures. Thirteen elderly women with a high risk of fall and fracture, aged 76-86, living in their own homes in rural areas, were recruited from a voluntary fracture prevention programme. All women had a history of fragility fractures and were interviewed in their homes from spring to autumn 2004. A phenomenological reflective lifeworld approach was chosen to analyse in-depth interview data. The study was conducted within an interdisciplinary research group inspired by dialogical research. Elderly women's life space has been narrowed due to advanced age, physical injury or by efforts to prevent new injuries leading to changes in self-perception. However, the women seek strategies to challenge limitations and insecurity, and strive to retain mobility and daily life routines. The four major constituents of the phenomenon 'elderly women's experiences of fall risk' emerged in this study: a changing body, living with precaution, ambiguous dependency and influence and need for understanding. Employing the women's thoughts and resources in trust-based dialogues with caregivers may strengthen their concord and the prospects to continue an active life. Elderly women seek strategies to challenge limitations and feelings of insecurity, and strive to maintain mobility and daily life routines. A trust-based care respecting the preferences of the women seemed to stimulate behavioural change in maintaining an active life.

  7. Calculation of Oxygen Fugacity in High Pressure Metal-Silicate Experiments and Comparison to Standard Approaches

    Science.gov (United States)

    Righter, K.; Ghiorso, M.

    2009-01-01

    Calculation of oxygen fugacity in high pressure and temperature experiments in metal-silicate systems is usually approximated by the ratio of Fe in the metal and FeO in the silicate melt: (Delta)IW=2*log(X(sub Fe)/X(sub FeO)), where IW is the iron-wustite reference oxygen buffer. Although this is a quick and easy calculation to make, it has been applied to a huge variety of metallic (Fe- Ni-S-C-O-Si systems) and silicate liquids (SiO2, Al2O3, TiO2, FeO, MgO, CaO, Na2O, K2O systems). This approach has surely led to values that have little meaning, yet are applied with great confidence, for example, to a terrestrial mantle at "IW-2". Although fO2 can be circumvented in some cases by consideration of Fe-M distribution coefficient, these do not eliminate the effects of alloy or silicate liquid compositional variation, or the specific chemical effects of S in the silicate liquid, for example. In order to address the issue of what the actual value of fO2 is in any given experiment, we have calculated fO2 from the equilibria 2Fe (metal) + SiO2 (liq) + O2 = Fe2SiO4 (liq).

  8. Quantitative PCR high-resolution melting (qPCR-HRM) curve analysis, a new approach to simultaneously screen point mutations and large rearrangements: application to MLH1 germline mutations in Lynch syndrome.

    Science.gov (United States)

    Rouleau, Etienne; Lefol, Cédrick; Bourdon, Violaine; Coulet, Florence; Noguchi, Tetsuro; Soubrier, Florent; Bièche, Ivan; Olschwang, Sylviane; Sobol, Hagay; Lidereau, Rosette

    2009-06-01

    Several techniques have been developed to screen mismatch repair (MMR) genes for deleterious mutations. Until now, two different techniques were required to screen for both point mutations and large rearrangements. For the first time, we propose a new approach, called "quantitative PCR (qPCR) high-resolution melting (HRM) curve analysis (qPCR-HRM)," which combines qPCR and HRM to obtain a rapid and cost-effective method suitable for testing a large series of samples. We designed PCR amplicons to scan the MLH1 gene using qPCR HRM. Seventy-six patients were fully scanned in replicate, including 14 wild-type patients and 62 patients with known mutations (57 point mutations and five rearrangements). To validate the detected mutations, we used sequencing and/or hybridization on a dedicated MLH1 array-comparative genomic hybridization (array-CGH). All point mutations and rearrangements detected by denaturing high-performance liquid chromatography (dHPLC)+multiplex ligation-dependent probe amplification (MLPA) were successfully detected by qPCR HRM. Three large rearrangements were characterized with the dedicated MLH1 array-CGH. One variant was detected with qPCR HRM in a wild-type patient and was located within the reverse primer. One variant was not detected with qPCR HRM or with dHPLC due to its proximity to a T-stretch. With qPCR HRM, prescreening for point mutations and large rearrangements are performed in one tube and in one step with a single machine, without the need for any automated sequencer in the prescreening process. In replicate, its reagent cost, sensitivity, and specificity are comparable to those of dHPLC+MLPA techniques. However, qPCR HRM outperformed the other techniques in terms of its rapidity and amount of data provided.

  9. The Chinese electricity access model for rural electrification: Approach, experience and lessons for others

    International Nuclear Information System (INIS)

    Bhattacharyya, Subhes C.; Ohiare, Sanusi

    2012-01-01

    The economic and infrastructural disparities between the rural and urban communities of most developing countries in general and in terms of energy access in particular are quite glaring. China presents a good example of a developing country that has successfully embarked on rural electrification projects over the last few decades and achieved a great feat of almost 100% electrification rate (. World Energy Outlook, 2009, International Energy Agency, Paris (see IEA website at (http://www.worldenergyoutlook.org/electricity.asp).)). The purpose of this paper is to find out how China has achieved this feat; how China’s rural energy projects were financed and whether China provides lessons for other countries to follow. The above questions are examined through an extensive literature review and the paper finds that unlike many other countries following the top-down approach to rural electrification, China has preferred to use a phased development through a bottom-up approach where local resources, and village level development and empowerment played an important role. While the state provided the overall guidance and financial support, the integrated rural development approach has produced local-level solutions that are subsequently integrated to produce an alternative development pathway. Strong government commitment, active local participation, technological flexibility and diversity, strong emphasis on rural development through agricultural and industrial activities and an emphasis on capacity building and training have also played an important role in the success. However, despite achieving the universal access objective, China still faces a number of issues related to rural electricity use, especially in terms of regional use patterns, long-term sustainability of supply and commercial operation of the systems. The Chinese model could serve as an inspiration for other developing countries trying to ensure universal electricity access. - Highlights: ► It

  10. Approaches to Modeling Coupled Flow and Reaction in a 2-D Cementation Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Steefel, Carl; Cochepin, B.; Trotignon, L.; Bildstein, O.; Steefel, C.; Lagneau, V.; van der Lee, J.

    2008-04-01

    Porosity evolution at reactive interfaces is a key process that governs the evolution and performances of many engineered systems that have important applications in earth and environmental sciences. This is the case, for example, at the interface between cement structures and clays in deep geological nuclear waste disposals. Although in a different transport regime, similar questions arise for permeable reactive barriers used for biogeochemical remediation in surface environments. The COMEDIE project aims at investigating the coupling between transport, hydrodynamics and chemistry when significant variations of porosity occur. The present work focuses on a numerical benchmark used as a design exercise for the future COMEDIE-2D experiment. The use of reactive transport simulation tools like Hytec and Crunch provides predictions of the physico-chemical evolutions that are expected during the future experiments in laboratory. Focus is given in this paper on the evolution during the simulated experiment of precipitate, permeability and porosity fields. A first case is considered in which the porosity is constant. Results obtained with Crunch and Hytec are in relatively good agreement. Differences are attributable to the models of reactive surface area taken into account for dissolution/precipitation processes. Crunch and Hytec simulations taking into account porosity variations are then presented and compared. Results given by the two codes are in qualitative agreement, with differences attributable in part to the models of reactive surface area for dissolution/precipitation processes. As a consequence, the localization of secondary precipitates predicted by Crunch leads to lower local porosities than for predictions obtained by Hytec and thus to a stronger coupling between flow and chemistry. This benchmark highlights the importance of the surface area model employed to describe systems in which strong porosity variations occur as a result of dissolution

  11. Deep-learnt classification of light curves

    DEFF Research Database (Denmark)

    Mahabal, Ashish; Gieseke, Fabian; Pai, Akshay Sadananda Uppinakudru

    2017-01-01

    is to derive statistical features from the time series and to use machine learning methods, generally supervised, to separate objects into a few of the standard classes. In this work, we transform the time series to two-dimensional light curve representations in order to classify them using modern deep......Astronomy light curves are sparse, gappy, and heteroscedastic. As a result standard time series methods regularly used for financial and similar datasets are of little help and astronomers are usually left to their own instruments and techniques to classify light curves. A common approach...... learning techniques. In particular, we show that convolutional neural networks based classifiers work well for broad characterization and classification. We use labeled datasets of periodic variables from CRTS survey and show how this opens doors for a quick classification of diverse classes with several...

  12. Generalization of drying curves in conductive/convective drying of cellulose

    Directory of Open Access Journals (Sweden)

    M. Stenzel

    2003-03-01

    Full Text Available The objective of this work is to analyze the possibility of applying the drying curves generalization methodology to the conductive/convective hot plate drying of cellulose. The experiments were carried out at different heated plate temperatures and air velocities over the surface of the samples. This kind of approach is very interesting because it permits comparison of the results of different experiments by reducing them to only one set, which can be divided into two groups: the generalized drying curves and the generalized drying rate curves. The experimental apparatus is an attempt to reproduce the operational conditions of conventional paper dryers (ratio of paper/air movement and consists of a metallic box heated by a thermostatic bath containing an upper surface on which the cellulose samples are placed. Sample material is short- and long-fiber cellulose sheets, about 1 mm thick, and ambient air was introduced into the system by a adjustable blower under different conditions. Long-fiber cellulose generalized curves were obtained and analyzed first individually and then together with the short-fiber cellulose results from Motta Lima et al. (2000 a,b. Finally, a set of equations to fit the generalized curves obtained was proposed and discussed.

  13. A population balance approach considering heat and mass transfer-Experiments and CFD simulations

    International Nuclear Information System (INIS)

    Krepper, Eckhard; Beyer, Matthias; Lucas, Dirk; Schmidtke, Martin

    2011-01-01

    Highlights: → The MUSIG approach was extended by mass transfer between the size groups to describe condensation or re-evaporation. → Experiments on steam bubble condensation in vertical co-current steam/water flows have been carried out. The cross sectional gas fraction distribution, the bubble size distribution ad the gas velocity profiles were measured. → The following phenomena could be reproduced with good agreement to the experiments: (a) Dependence of the condensation rate on the initial bubble size distribution and (b) re-evaporation over the height in tests with low inlet temperature subcooling. - Abstract: Bubble condensation in sub-cooled water is a complex process, to which various phenomena contribute. Since the condensation rate depends on the interfacial area density, bubble size distribution changes caused by breakup and coalescence play a crucial role. Experiments on steam bubble condensation in vertical co-current steam/water flows have been carried out in an 8 m long vertical DN200 pipe. Steam is injected into the pipe and the development of the bubbly flow is measured at different distances to the injection using a pair of wire mesh sensors. By varying the steam nozzle diameter the initial bubble size can be influenced. Larger bubbles come along with a lower interfacial area density and therefore condensate slower. Steam pressures between 1 and 6.5 MPa and sub-cooling temperatures from 2 to 12 K were applied. Due to the pressure drop along the pipe, the saturation temperature falls towards the upper pipe end. This affects the sub-cooling temperature and can even cause re-evaporation in the upper part of the test section. The experimental configurations are simulated with the CFD code CFX using an extended MUSIG approach, which includes the bubble shrinking or growth due to condensation or re-evaporation. The development of the vapour phase along the pipe with respect to vapour void fractions and bubble sizes is qualitatively well reproduced

  14. Robotic Mitral Valve Repair: The Learning Curve.

    Science.gov (United States)

    Goodman, Avi; Koprivanac, Marijan; Kelava, Marta; Mick, Stephanie L; Gillinov, A Marc; Rajeswaran, Jeevanantham; Brzezinski, Anna; Blackstone, Eugene H; Mihaljevic, Tomislav

    Adoption of robotic mitral valve surgery has been slow, likely in part because of its perceived technical complexity and a poorly understood learning curve. We sought to correlate changes in technical performance and outcome with surgeon experience in the "learning curve" part of our series. From 2006 to 2011, two surgeons undertook robotically assisted mitral valve repair in 458 patients (intent-to-treat); 404 procedures were completed entirely robotically (as-treated). Learning curves were constructed by modeling surgical sequence number semiparametrically with flexible penalized spline smoothing best-fit curves. Operative efficiency, reflecting technical performance, improved for (1) operating room time for case 1 to cases 200 (early experience) and 400 (later experience), from 414 to 364 to 321 minutes (12% and 22% decrease, respectively), (2) cardiopulmonary bypass time, from 148 to 102 to 91 minutes (31% and 39% decrease), and (3) myocardial ischemic time, from 119 to 75 to 68 minutes (37% and 43% decrease). Composite postoperative complications, reflecting safety, decreased from 17% to 6% to 2% (63% and 85% decrease). Intensive care unit stay decreased from 32 to 28 to 24 hours (13% and 25% decrease). Postoperative stay fell from 5.2 to 4.5 to 3.8 days (13% and 27% decrease). There were no in-hospital deaths. Predischarge mitral regurgitation of less than 2+, reflecting effectiveness, was achieved in 395 (97.8%), without correlation to experience; return-to-work times did not change substantially with experience. Technical efficiency of robotic mitral valve repair improves with experience and permits its safe and effective conduct.

  15. F(α) curves: Experimental results

    International Nuclear Information System (INIS)

    Glazier, J.A.; Gunaratne, G.; Libchaber, A.

    1988-01-01

    We study the transition to chaos at the golden and silver means for forced Rayleigh-Benard (RB) convection in mercury. We present f(α) curves below, at, and above the transition, and provide comparisons to the curves calculated for the one-dimensional circle map. We find good agreement at both the golden and silver means. This confirms our earlier observation that for low amplitude forcing, forced RB convection is well described by the one-dimensional circle map and indicates that the f(α) curve is a good measure of the approach to criticality. For selected subcritical experimental data sets we calculate the degree of subcriticality. We also present both experimental and calculated results for f(α) in the presence of a third frequency. Again we obtain agreement: The presence of random noise or a third frequency narrows the right-hand (negative q) side of the f(α) curve. Subcriticality results in symmetrically narrowed curves. We can also distinguish these cases by examining the power spectra and Poincare sections of the time series

  16. Experience on implementation of the Integrated Safeguards approach for the MOX facility from the operator's point of view

    International Nuclear Information System (INIS)

    Nomi, Takayoshi; Nagatani, Taketeru; Ninagawa, Junichi; Nakajima, Shinji; Maruyama, Hajime; Asano, Takashi; Fujiwara, Shigeo

    2011-01-01

    The IS approach for the JNC-1 site was implemented in August 2008, and this was the first experience in the world. This IS approach aimed not only to improve efficiency and effectiveness of safeguards but also to reduce burden of the plant operation by improvement of efficiency of the inspection activity. It was planned to review effectiveness of this new approach after three years from implementation. And JAEA also evaluated effects by application of the IS approach for two MOX fuel facilities in the JNC-1 site based on the three years experiences from the operator's view point. As the result of evaluation, it was confirmed that there were some difference of benefits by application of the IS approach depending on features of the facility, automation level of equipment and advance level of safeguards systems. (author)

  17. Models of genus one curves

    OpenAIRE

    Sadek, Mohammad

    2010-01-01

    In this thesis we give insight into the minimisation problem of genus one curves defined by equations other than Weierstrass equations. We are interested in genus one curves given as double covers of P1, plane cubics, or complete intersections of two quadrics in P3. By minimising such a curve we mean making the invariants associated to its defining equations as small as possible using a suitable change of coordinates. We study the non-uniqueness of minimisations of the genus one curves des...

  18. AREVA NP decontamination concept for decommissioning. A comprehensive approach based on over 30 years experience

    International Nuclear Information System (INIS)

    Stiepani, Christoph

    2011-01-01

    Decontamination prior to Decommissioning and Dismantlement is imperative. Not only does it provide for minimization of personnel dose exposure but also maximization of the material volume available for free release. Since easier dismantling techniques in lower dose areas can be applied, the licensing process is facilitated and the scheduling and budgeting effort is more reliable. The most internationally accepted approach for Decontamination prior to Decommissioning projects is the Full System Decontamination (FSD). FSD is defined as the chemical decontamination of the primary cooling circuit, in conjunction with the main auxiliary systems. AREVA NP has long-term experience with Full System Decontamination for return to service of operating nuclear power plants as well as for decommissioning after shutdown. Since 1976, AREVA NP has performed over 500 decontamination applications and, from 1986, Decontaminations prior to Decommissioning projects which comprise virtually all NPP designs and plant conditions were performed: NPP designs: HPWR, PWR, and BWR by AREVA, Westinghouse, ABB and GE. Decontaminations performed shortly after final shutdown or several years later, and even after re-opening Safe Enclosure. High Alpha inventory and or low gamma/alpha ratio. Main Coolant chemistry (e.g., with and without Zn injection during operation). Fifteen Decontaminations prior to Decommissioning Projects have been performed successfully to date and the sixteenth FSD is now in the detailed engineering phase and is scheduled to commence late 2010. AREVA NP has developed a fully comprehensive approach for decontamination based on the CORD® (Chemical Oxidation Reduction Decontamination) Family, applied using the in-house designed decontamination equipment AMDA TM (Automatic Modular Decontamination Appliance). Based on the vast experience of AREVA NP in the field of decontamination, the Decontamination Concept for Decommissioning was developed. This concept ensures that the

  19. Children's unique experience of depression: Using a developmental approach to predict variation in symptomatology

    Directory of Open Access Journals (Sweden)

    Ginicola Misty M

    2007-08-01

    Full Text Available Abstract Background Current clinical knowledge suggests that children can have different types of depressive symptoms (irritability and aggression, but presents no theoretical basis for these differences. Using a developmental approach, the present study sought to test the relationship between developmental level (mental age and expression of depressive symptoms. The primary hypothesis was that as children's mental age increased, so would the number of internalizing symptoms present. Methods Participants were 252 psychiatric inpatients aged 4 to 16 with a diagnosed depressive disorder. All children were diagnosed by trained clinicians using DSM criteria. Patients were predominantly male (61% with varied ethnic backgrounds (Caucasian 54%; African American 22%; Hispanic 19%; Other 5%. Children were given an IQ test (KBIT or WISC while within the hospital. Mental age was calculated by using the child's IQ score and chronological age. Four trained raters reviewed children's records for depressive symptoms as defined by the DSM-IV TR. Additionally, a ratio score was calculated to indicate the number of internalizing symptoms to total symptoms. Results Mental age positively correlated (r = .51 with an internalizing total symptom ratio score and delineated between several individual symptoms. Mental age also predicted comorbidity with anxiety and conduct disorders. Children of a low mental age were more likely to be comorbid with conduct disorders, whereas children with a higher mental age presented more often with anxiety disorders. Gender was independently related to depressive symptoms, but minority status interacted with mental age. Conclusion The results of this study indicate that a developmental approach is useful in understanding children's depressive symptoms and has implications for both diagnosis and treatment of depression. If children experience depression differently, it follows that treatment options may also differ from that which is

  20. Combining Digital Archives Content with Serious Game Approach to Create a Gamified Learning Experience

    Directory of Open Access Journals (Sweden)

    D.-T. Shih

    2015-08-01

    Full Text Available This paper presents an interdisciplinary to develop content-aware application that combines game with learning on specific categories of digital archives. The employment of content-oriented game enhances the gamification and efficacy of learning in culture education on architectures and history of Hsinchu County, Taiwan. The gamified form of the application is used as a backbone to support and provide a strong stimulation to engage users in learning art and culture, therefore this research is implementing under the goal of “The Digital ARt/ARchitecture Project”. The purpose of the abovementioned project is to develop interactive serious game approaches and applications for Hsinchu County historical archives and architectures. Therefore, we present two applications, “3D AR for Hukou Old ” and “Hsinchu County History Museum AR Tour” which are in form of augmented reality (AR. By using AR imaging techniques to blend real object and virtual content, the users can immerse in virtual exhibitions of Hukou Old Street and Hsinchu County History Museum, and to learn in ubiquitous computing environment. This paper proposes a content system that includes tools and materials used to create representations of digitized cultural archives including historical artifacts, documents, customs, religion, and architectures. The Digital ARt / ARchitecture Project is based on the concept of serious game and consists of three aspects: content creation, target management, and AR presentation. The project focuses on developing a proper approach to serve as an interactive game, and to offer a learning opportunity for appreciating historic architectures by playing AR cards. Furthermore, the card game aims to provide multi-faceted understanding and learning experience to help user learning through 3D objects, hyperlinked web data, and the manipulation of learning mode, and then effectively developing their learning levels on cultural and historical archives in

  1. Combining Digital Archives Content with Serious Game Approach to Create a Gamified Learning Experience

    Science.gov (United States)

    Shih, D.-T.; Lin, C. L.; Tseng, C.-Y.

    2015-08-01

    This paper presents an interdisciplinary to develop content-aware application that combines game with learning on specific categories of digital archives. The employment of content-oriented game enhances the gamification and efficacy of learning in culture education on architectures and history of Hsinchu County, Taiwan. The gamified form of the application is used as a backbone to support and provide a strong stimulation to engage users in learning art and culture, therefore this research is implementing under the goal of "The Digital ARt/ARchitecture Project". The purpose of the abovementioned project is to develop interactive serious game approaches and applications for Hsinchu County historical archives and architectures. Therefore, we present two applications, "3D AR for Hukou Old " and "Hsinchu County History Museum AR Tour" which are in form of augmented reality (AR). By using AR imaging techniques to blend real object and virtual content, the users can immerse in virtual exhibitions of Hukou Old Street and Hsinchu County History Museum, and to learn in ubiquitous computing environment. This paper proposes a content system that includes tools and materials used to create representations of digitized cultural archives including historical artifacts, documents, customs, religion, and architectures. The Digital ARt / ARchitecture Project is based on the concept of serious game and consists of three aspects: content creation, target management, and AR presentation. The project focuses on developing a proper approach to serve as an interactive game, and to offer a learning opportunity for appreciating historic architectures by playing AR cards. Furthermore, the card game aims to provide multi-faceted understanding and learning experience to help user learning through 3D objects, hyperlinked web data, and the manipulation of learning mode, and then effectively developing their learning levels on cultural and historical archives in Hsinchu County.

  2. Semicircular Horizontal Approach in Breast Reduction: Clinical Experience in 38 Cases

    Directory of Open Access Journals (Sweden)

    Hee Su Shin

    2015-07-01

    Full Text Available BackgroundVarious techniques are used for performing breast reduction. Wise-pattern and vertical scar techniques are the most commonly employed approaches. However, a vertical scar in the mid-lower breast is prominent and aesthetically less pleasant. In contrast, a semicircular horizontal approach does not leave a vertical scar in the mid breast and transverse scars can be hidden in the inframammary fold. In this paper, we describe the experiences and results of semicircular horizontal breast reductions performed by a single surgeon.MethodsBetween September 1996 and October 2013, our senior author used this technique in 38 cases in the US and at our institution. We used a superiorly based semicircular incision, where the upper skin paddle was pulled down to the inframammary fold with the nipple-areola complex pulled through the keyhole.ResultsThe average total reduction per breast was 584 g, ranging from 286 to 794 g. The inferior longitudinal pedicle was used in all the cases. The average reduction of the distance from the sternal notch to the nipple was 13 cm (range, 11-15 cm. The mean decrease in the bra cup size was 1.7 cup sizes (range, a decrease of 1 to 3. We obtained very satisfactory results with a less noticeable scar, no complication such as necrosis of the nipple or the skin flap, wound infection, aseptic necrosis of the breast tissue, or wound dehiscence. One patient had a small hematoma that resolved spontaneously.ConclusionsThis technique is straightforward and easy to learn, and offers a safe, effective, and predictable way for treating mammary hypertrophy.

  3. Caries experience of Egyptian adolescents: does the atraumatic restorative treatment approach offer a solution?

    Science.gov (United States)

    Mobarak, E H; Shabayek, M M; Mulder, J; Reda, A H; Frencken, J E

    2011-01-01

    To assess the prevalence and severity of dental caries amongst Egyptian adolescents and the prevalence of carious lesions treatable through the atraumatic restorative treatment (ART) approach. Using a convenient sample procedure, two secondary schools with a dental clinic were selected (967 students, average age: 13.7 ± 0.8 years, range: 12-15). Dental caries was diagnosed using the ART caries criteria, and plaque and calculus were assessed using the Green and Vermillion criteria amongst students grades 1-3 in the dental clinic by 3 calibrated examiners. The effect of the independent variables gender, age, tooth surface, jaw side (left or right) and type of jaw (mandible/maxilla) on dependent caries experience variables and D(2) and D(3) variables were tested using ANOVA. The prevalence of dental caries including enamel lesion (D(2)MFT) amongst the 967 students was 51.4% and that of dental caries excluding enamel lesions (D(3)MFT) was 38.1%. The mean D(2)MFT and D(3)MFT scores were 1.5 and 0.8, respectively. The percentage of teeth filled and extracted was low. Female students had statistically significantly higher mean D(3)MFT/S and D(2)MFT/S scores than males (p ART was 48% for score 2 and 28% for score 3. Most of the cavitated lesions were found untreated despite the presence of a dental clinic and a dentist on the school premises. The majority of cavitated lesions without pulp involvement could be treated using the preventive and restorative components of the ART approach. Copyright © 2011 S. Karger AG, Basel.

  4. Sexual Experience of Iranian Women in Their Middle Life: A Qualitative Approach.

    Science.gov (United States)

    Moghasemi, Sedigheh; Ozgoli, Giti; Ahmadi, Fazlollah; Simbar, Masomeh

    2018-01-01

    Sexual problems are common among the middle-aged women; however, there is no deep understanding of sexuality in midlife. The current study aimed to investigate Iranian women's attitudes and experiences about sexual life changes in midlife. This is a descriptive qualitative study. Seventeen women aged 40 -65 years old were purposively selected from urban health centers in Gorgan, Iran, in 2015. Face-to-face, semi-structured and in-depth interviews were conducted for data collection until data saturation was attained. The resulting data were analyzed based on Graneheim and Lundman's approach. MAXQDA 10 was used for organization of data. Data analysis demonstrated seventh sub-themes and three themes. The emerged themes were entitled (1) "Continuous paradox over being a sexual agent" with three subthemes of beliefs on asexuality as socially accepted view for women in midlife, changing in motivation for sex and changing in sexual performance, (2) "Considering menopause; opportunities and threats for sexual life" with two subthemes of menopause related cons for sexual life and menopause related pros in sexual life, and (3) "Coping strategies for changes in sexuality in midlife" with two subthemes of different psychological reactions to changes that have influenced the sex and take practical steps for restoration of sexual attraction. The findings demonstrated that middle-aged women in a male-dominant culture encounter paradox over being a sexual agent. In a bio-psycho-social approach, they perceived menopause as an opportunity or threat for their own sexuality. Following the conflicts, threats and changes of sexuality in midlife, they adopt diverse coping strategies to improve their sexual relationships and preserve their family.

  5. Sexual Experience of Iranian Women in Their Middle Life: A Qualitative Approach

    Directory of Open Access Journals (Sweden)

    Sedigheh Moghasemi

    2018-01-01

    Full Text Available Background: Sexual problems are common among the middle-aged women; however, there is no deep understanding of sexuality in midlife. The current study aimed to investigate Iranian women’s attitudes and experiences about sexual life changes in midlife. Methods: This is a descriptive qualitative study. Seventeen women aged 40 -65 years old were purposively selected from urban health centers in Gorgan, Iran, in 2015. Face-to-face, semi-structured and in-depth interviews were conducted for data collection until data saturation was attained. The resulting data were analyzed based on Graneheim and Lundman’s approach. MAXQDA 10 was used for organization of data. Results: Data analysis demonstrated seventh sub-themes and three themes. The emerged themes were entitled (1 “Continuous paradox over being a sexual agent” with three subthemes of beliefs on asexuality as socially accepted view for women in midlife, changing in motivation for sex and changing in sexual performance, (2 “Considering menopause; opportunities and threats for sexual life” with two subthemes of menopause related cons for sexual life and menopause related pros in sexual life, and (3 “Coping strategies for changes in sexuality in midlife” with two subthemes of different psychological reactions to changes that have influenced the sex and take practical steps for restoration of sexual attraction. Conclusion: The findings demonstrated that middle-aged women in a male-dominant culture encounter paradox over being a sexual agent. In a bio-psycho-social approach, they perceived menopause as an opportunity or threat for their own sexuality. Following the conflicts, threats and changes of sexuality in midlife, they adopt diverse coping strategies to improve their sexual relationships and preserve their family.

  6. Power uprates in nuclear power plants: international experiences and approaches for implementation

    International Nuclear Information System (INIS)

    Kang, Ki Sig

    2008-01-01

    The greater demand for electricity and the available capacity within safety margins in some operating NPPs are prompting nuclear utilities to request license modification to enable operation at a higher power level, beyond their original license provisions. Such plant modifications require an in-depth safety analysis to evaluate the possible safety impact. The analysis must consider the thermo hydraulic, radiological and structural aspects, and the plant behavior, while taking into account the capability of the structures, systems and components, and the reactor protection and safeguard systems set points. The purpose of this paper is to introduce international experiences and approaches for implementation of power uprates related to the reactor thermal power of nuclear power plants. The paper is intended to give the reader a general overview of the major processes, work products, issues, challenges, events, and experiences in the power uprates program. The process of increasing the licensed power level of a nuclear power plants is called a power uprate. One way of increasing the thermal output from a reactor is to increase the amount of fissile material in use. It is also possible to increase the core power by increasing the performance of the high power bundles. Safety margins can be maintained by either using fuels with a higher performance, or through the use of improved methods of analysis to demonstrate that the required margins are retained even at the higher power levels. The paper will review all types of power uprates, from small to large, and across various reactor types, including light and heavy water, pressurized, and boiling water reactors. Generally, however, the content of the report focuses on power uprates of the stretch and extended type. The International Atomic Energy Agency (IAEA) is developing a technical guideline on power uprates and side effects of power uprates in nuclear power plants

  7. Science-Based Approach for Advancing Marine and Hydrokinetic Energy: Integrating Numerical Simulations with Experiments

    Science.gov (United States)

    Sotiropoulos, F.; Kang, S.; Chamorro, L. P.; Hill, C.

    2011-12-01

    experimentally in the St. Anthony Falls Laboratory Main Channel. The experiments and simulations are compared with each other and shown to be in very good agreement both in terms of the mean flow and the turbulence statistics. The results are analyzed to study the structure of turbulence in the wake of the turbine and also identify the effects of turbulent fluctuations in the approach flow on the power produced by the turbine. Overall our results make a strong case that high-resolution numerical modeling, validated with detailed laboratory measurements, is a viable tool for assessing and optimizing the performance of MHK devices.

  8. Path integrals on curved manifolds

    International Nuclear Information System (INIS)

    Grosche, C.; Steiner, F.

    1987-01-01

    A general framework for treating path integrals on curved manifolds is presented. We also show how to perform general coordinate and space-time transformations in path integrals. The main result is that one has to subtract a quantum correction ΔV ∝ ℎ 2 from the classical Lagrangian L, i.e. the correct effective Lagrangian to be used in the path integral is L eff = L-ΔV. A general prescription for calculating the quantum correction ΔV is given. It is based on a canonical approach using Weyl-ordering and the Hamiltonian path integral defined by the midpoint prescription. The general framework is illustrated by several examples: The d-dimensional rotator, i.e. the motion on the sphere S d-1 , the path integral in d-dimensional polar coordinates, the exact treatment of the hydrogen atom in R 2 and R 3 by performing a Kustaanheimo-Stiefel transformation, the Langer transformation and the path integral for the Morse potential. (orig.)

  9. Design of experiments approach to engineer cell-secreted matrices for directing osteogenic differentiation.

    Science.gov (United States)

    Decaris, Martin L; Leach, J Kent

    2011-04-01

    The presentation of extracellular matrix (ECM) proteins provides an opportunity to instruct the phenotype and behavior of responsive cells. Decellularized cell-secreted matrix coatings (DM) represent a biomimetic culture surface that retains the complexity of the natural ECM. Microenvironmental culture conditions alter the composition of these matrices and ultimately the ability of DMs to direct cell fate. We employed a design of experiments (DOE) multivariable analysis approach to determine the effects and interactions of four variables (culture duration, cell seeding density, oxygen tension, and media supplementation) on the capacity of DMs to direct the osteogenic differentiation of human mesenchymal stem cells (hMSCs). DOE analysis revealed that matrices created with extended culture duration, ascorbate-2-phosphate supplementation, and in ambient oxygen tension exhibited significant correlations with enhanced hMSC differentiation. We validated the DOE model results using DMs predicted to have superior (DM1) or lesser (DM2) osteogenic potential for naïve hMSCs. Compared to cells on DM2, hMSCs cultured on DM1 expressed 2-fold higher osterix levels and deposited 3-fold more calcium over 3 weeks. Cells on DM1 coatings also exhibited greater proliferation and viability compared to DM2-coated substrates. This study demonstrates that DOE-based analysis is a powerful tool for optimizing engineered systems by identifying significant variables that have the greatest contribution to the target output.

  10. Adopting a blended approach to learning: Experiences from Radiography at Queen Margaret University, Edinburgh

    International Nuclear Information System (INIS)

    Cockbain, M.M.; Blyth, C.M.; Bovill, C.; Morss, K.

    2009-01-01

    The perspective of the radiography teaching team at Queen Margaret University (QMU) was that a transmission mode of programme delivery was sub-optimal in helping students to learn and make links between theory and practice. Programme redesign adopted a blended learning approach with both face-to-face and online learning aimed at enhancing the students' control over their own learning. Online tasks within Web Classroom Tools (WebCT) were used as an integral part of careful programme design, which resulted in a programme enabling synthesis of the skills, knowledge and competencies acquired in the academic and clinical environments. With the move towards a more learner-centred, blended educational experience for the students the lecturers' role shifted to that of facilitator with WebCT providing the tutor with a more transparent view of student learning. Lecturers plan learning activities that build upon the skills students have developed through learning in groups, online and in class. The explicit connections that now exist between the academic programme and the opportunities for applying knowledge in practice allow students to engage more deeply in their learning.

  11. Developing reflection on competence-based learning: the Russian experience with the Tuning approach

    Directory of Open Access Journals (Sweden)

    Anna Serbati

    2014-07-01

    Full Text Available The paper focuses on the Tuning Russia project. It aims at providing an overview of the impact of the Tuning methodology and outcomes concerning University teaching, learning, and assessment activities. It identifies: the most relevant results and “lesson learnt” during the project; tools/concepts/experiences that involved teachers found most interesting; strengths and weaknesses; the usefulness of working with colleagues from different Russian universities; and the level of sharing of the Tuning methodology with other colleagues within participating Universities. The empirical data for the study were drawn from a qualitative questionnaire with open questions filled-in by the members of the subject area group “Social Work” involved in the Tuning Russia project. The respondents were six academic teachers from different Russian universities and two European Tuning experts. This reflection by academic teachers upon the initial implementation of the Tuning approach in Russia highlights the opportunities to explore methods of establishing and improving communities of practice in the field of competence-based higher education curriculum development. Results highlight the need to develop further work concerning both summative and formative evaluation in relation to competence-based curricula review in higher education

  12. Scientific approach and practical experience for reconstruction of waste water treatment plants in Russia

    Directory of Open Access Journals (Sweden)

    Makisha Nikolay

    2017-01-01

    Full Text Available Protection of water bodies has a strict dependence on reliable operation of engineering systems and facilities for water supply and sewage. The majority of these plants and stations has been constructed in 1970-1980's in accordance with rules and regulations of that time. So now most of them require reconstruction due to serious physical or/and technological wear. The current condition of water supply and sewage systems and facilities frequently means a hidden source of serious danger for normal life support and ecological safety of cities and towns. The article reveals an obtained experience and modern approaches for reconstruction of waste water and sludge treatment plants that proved their efficiency even if applied in limited conditions such as area limits, investments limits. The main directions of reconstruction: overhaul repair and partial modernization of existing facilities on the basis of initial project; - restoration and modernization of existing systems on the basis on the current documents and their current condition; upgrade of waste water treatment plants (WWTPs performance on the basis of modern technologies and methods; reconstruction of sewage systems and facilities and treatment quality improvement.

  13. Scientific approach and practical experience for reconstruction of waste water treatment plants in Russia

    Science.gov (United States)

    Makisha, Nikolay; Gogina, Elena

    2017-11-01

    Protection of water bodies has a strict dependence on reliable operation of engineering systems and facilities for water supply and sewage. The majority of these plants and stations has been constructed in 1970-1980's in accordance with rules and regulations of that time. So now most of them require reconstruction due to serious physical or/and technological wear. The current condition of water supply and sewage systems and facilities frequently means a hidden source of serious danger for normal life support and ecological safety of cities and towns. The article reveals an obtained experience and modern approaches for reconstruction of waste water and sludge treatment plants that proved their efficiency even if applied in limited conditions such as area limits, investments limits. The main directions of reconstruction: overhaul repair and partial modernization of existing facilities on the basis of initial project; - restoration and modernization of existing systems on the basis on the current documents and their current condition; upgrade of waste water treatment plants (WWTPs) performance on the basis of modern technologies and methods; reconstruction of sewage systems and facilities and treatment quality improvement.

  14. A Systems Approach Framework for the Transition to Sustainable Development: Potential Value Based on Coastal Experiments

    Directory of Open Access Journals (Sweden)

    Tom S. Hopkins

    2012-09-01

    Full Text Available This article explores the value of the Systems Approach Framework (SAF as a tool for the transition to sustainable development in coastal zone systems, based on 18 study sites in Europe, where the SAF was developed and tested. The knowledge gained from these experiments concerns the practical aspects of (a governance in terms of policy effectiveness, (b sustainability science in terms of applying transdisciplinary science to social-ecological problems, and (c simulation analysis in terms of quantifying dysfunctions in complex systems. This new knowledge can help broaden our perspectives on how research can be changed to better serve society. The infusion of systems thinking into research and policy making leads to a preference for multi-issue instead of single-issue studies, an expansion from static to dynamic indicators, an understanding of the boundaries between system-dependent and system-independent problems, and the inclusion of non-market evaluations. It also develops a real partnership among research, management, and stakeholders to establish a quantitative basis for collaborative decision making. Furthermore, the article argues that the transition to sustainable development for coastal systems requires consideration of the scale interdependency from individual to global and recognition of the probable global reorganizational emergence of scale-free networks that could cooperate to maximize the integrated sustainability among them.

  15. A Comprehensive Approach to Post-Conflict Reconstruction: German Experience in Afghanistan

    Directory of Open Access Journals (Sweden)

    Philip Olegovich Trunov

    2016-12-01

    Full Text Available As a part of a larger research project on complex linkages between security and development implemented by the Center for Security and Development Studies at the Lomonosov Moscow State University, this paper examines the complex dilemmas of pursuing comprehensive approach to post-conflict reconstruction with an example of Federal Republic of Germany’s experience with the Provincial Reconstruction Teams (PRTs in Afghanistan after the terrorist attacks of 9/11. The first section depicts the background of deployment of the PRTs on Afghan territory. The second section compares the U.S., British and German models of PRTs and assesses the role of those teams as vehicles of close civil-military, interagency coordination. The third and the fourth sections identify respectively characteristic features of the German PRTs’ activities in Kunduz and Badakhshan provinces and the main obstacles that hindered the achievement of key objectives. The conclusion contains a concise assessment of effectiveness and efficiency of PRTs as a mechanism of addressing complex challenges of post-conflict reconstruction and transition to peaceful development. It also postulates that the PRT model, regardless of some objective difficulties faced by various German agencies, may be very relevant in the future in fulfilling a revised agenda of the German foreign and defense policies in the XXI century.

  16. Transport of sulfadiazine in soil columns — Experiments and modelling approaches

    Science.gov (United States)

    Wehrhan, Anne; Kasteel, Roy; Simunek, Jirka; Groeneweg, Joost; Vereecken, Harry

    2007-01-01

    Antibiotics, such as sulfadiazine, reach agricultural soils directly through manure of grazing livestock or indirectly through the spreading of manure or sewage sludge on the field. Knowledge about the fate of antibiotics in soils is crucial for assessing the environmental risk of these compounds, including possible transport to the groundwater. Transport of 14C-labelled sulfadiazine was investigated in disturbed soil columns at a constant flow rate of 0.26 cm h - 1 near saturation. Sulfadiazine was applied in different concentrations for either a short or a long pulse duration. Breakthrough curves of sulfadiazine and the non-reactive tracer chloride were measured. At the end of the leaching period the soil concentration profiles were determined. The peak maxima of the breakthrough curves were delayed by a factor of 2 to 5 compared to chloride and the decreasing limbs are characterized by an extended tailing. However, the maximum relative concentrations differed as well as the eluted mass fractions, ranging from 18 to 83% after 500 h of leaching. To identify relevant sorption processes, breakthrough curves of sulfadiazine were fitted with a convective-dispersive transport model, considering different sorption concepts with one, two and three sorption sites. Breakthrough curves can be fitted best with a three-site sorption model, which includes two reversible kinetic and one irreversible sorption site. However, the simulated soil concentration profiles did not match the observations for all of the used models. Despite this incomplete process description, the obtained results have implications for the transport behavior of sulfadiazine in the field. Its leaching may be enhanced if it is frequently applied at higher concentrations.

  17. Quantum fields in curved space

    International Nuclear Information System (INIS)

    Birrell, N.D.; Davies, P.C.W.

    1982-01-01

    The book presents a comprehensive review of the subject of gravitational effects in quantum field theory. Quantum field theory in Minkowski space, quantum field theory in curved spacetime, flat spacetime examples, curved spacetime examples, stress-tensor renormalization, applications of renormalization techniques, quantum black holes and interacting fields are all discussed in detail. (U.K.)

  18. Satellite altimetry based rating curves throughout the entire Amazon basin

    Science.gov (United States)

    Paris, A.; Calmant, S.; Paiva, R. C.; Collischonn, W.; Silva, J. S.; Bonnet, M.; Seyler, F.

    2013-05-01

    experiment shows that the stochastic approach is more efficient than the determinist one. By using for the parameters prior credible intervals defined by the user, this method provides an estimate of best rating curve estimate without any unlikely parameter, and all sites achieved convergence before reaching the maximum number of model evaluations. Results were assessed trough the Nash Sutcliffe efficiency coefficient, applied both to discharge and logarithm of discharges. Most of the virtual stations had good or very good results, showing values of Ens going from 0.7 to 0.98. However, worse results were found at a few virtual stations, unveiling the necessity of investigating possibilities of segmentation of the rating curve, depending on the stage or the rising or recession limb, but also possible errors in the altimetry series.

  19. Resonance of curved nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Calabri, L [CNR-INFM-National Research Center on nanoStructures and bioSystems at Surfaces (S3), Via Campi 213/a, 41100 Modena (Italy); Pugno, N [Department of Structural Engineering and Geotechnics, Politecnico di Torino, Turin (Italy); Ding, W [Department of Mechanical Engineering, Northwestern University, Evanston, IL 60208-3111 (United States); Ruoff, R S [Department of Mechanical Engineering, Northwestern University, Evanston, IL 60208-3111 (United States)

    2006-08-23

    The effects of non-ideal experimental configuration on the mechanical resonance of boron (B) nanowires (NWs) were studied to obtain the corrected value for the Young's modulus. The following effects have been theoretically considered: (i) the presence of intrinsic curvature (ii) non-ideal clamps (iii) spurious masses (iv) coating layer, and (v) large displacements. An energy-based analytical analysis was developed to treat such effects and their interactions. Here, we focus on treating the effect of the intrinsic curvature on the mechanical resonance. The analytical approach has been confirmed by numerical FEM analysis. A parallax method was used to obtain the three-dimensional geometry of the NW.

  20. Modelling stochastic chances in curve shape, with an application to cancer diagnostics

    DEFF Research Database (Denmark)

    Hobolth, A; Jensen, Eva B. Vedel

    2000-01-01

    Often, the statistical analysis of the shape of a random planar curve is based on a model for a polygonal approximation to the curve. In the present paper, we instead describe the curve as a continuous stochastic deformation of a template curve. The advantage of this continuous approach is that t......Often, the statistical analysis of the shape of a random planar curve is based on a model for a polygonal approximation to the curve. In the present paper, we instead describe the curve as a continuous stochastic deformation of a template curve. The advantage of this continuous approach...... is that the parameters in the model do not relate to a particular polygonal approximation. A somewhat similar approach has been used by Kent et al. (1996), who describe the limiting behaviour of a model with a first-order Markov property as the landmarks on the curve become closely spaced; see also Grenander(1993...

  1. Cosmological applications of algebraic quantum field theory in curved spacetimes

    CERN Document Server

    Hack, Thomas-Paul

    2016-01-01

    This book provides a largely self-contained and broadly accessible exposition on two cosmological applications of algebraic quantum field theory (QFT) in curved spacetime: a fundamental analysis of the cosmological evolution according to the Standard Model of Cosmology; and a fundamental study of the perturbations in inflation. The two central sections of the book dealing with these applications are preceded by sections providing a pedagogical introduction to the subject. Introductory material on the construction of linear QFTs on general curved spacetimes with and without gauge symmetry in the algebraic approach, physically meaningful quantum states on general curved spacetimes, and the backreaction of quantum fields in curved spacetimes via the semiclassical Einstein equation is also given. The reader should have a basic understanding of General Relativity and QFT on Minkowski spacetime, but no background in QFT on curved spacetimes or the algebraic approach to QFT is required.

  2. Theoretical Antecedents of Standing at Work: An Experience Sampling Approach Using the Theory of Planned Behavior

    Science.gov (United States)

    Meyer, M. Renée Umstattd; Wu, Cindy; Walsh, Shana M.

    2016-01-01

    Time spent sitting has been associated with an increased risk of diabetes, cancer, obesity, and mental health impairments. However, 75% of Americans spend most of their days sitting, with work-sitting accounting for 63% of total daily sitting time. Little research examining theory-based antecedents of standing or sitting has been conducted. This lack of solid groundwork makes it difficult to design effective intervention strategies to decrease sitting behaviors. Using the Theory of Planned Behavior (TPB) as our theoretical lens to better understand factors related with beneficial standing behaviors already being practiced, we examined relationships between TPB constructs and time spent standing at work among “positive deviants” (those successful in behavior change). Experience sampling methodology (ESM), 4 times a day (midmorning, before lunch, afternoon, and before leaving work) for 5 consecutive workdays (Monday to Friday), was used to assess employees' standing time. TPB scales assessing attitude (α = 0.81–0.84), norms (α = 0.83), perceived behavioral control (α = 0.77), and intention (α = 0.78) were developed using recommended methods and collected once on the Friday before the ESM surveys started. ESM data are hierarchically nested, therefore we tested our hypotheses using multilevel structural equation modeling with Mplus. Hourly full-time university employees (n = 50; 70.6% female, 84.3% white, mean age = 44 (SD = 11), 88.2% in full-time staff positions) with sedentary occupation types (time at desk while working ≥6 hours/day) participated. A total of 871 daily surveys were completed. Only perceived behavioral control (β = 0.45, p deviance approach to enhance perceived behavioral control, in addition to implementing environmental changes like installing standing desks. PMID:29546189

  3. Diagnostic Approaches to Sjögren’s Syndrome: a Literature Review and Own Clinical Experience

    Directory of Open Access Journals (Sweden)

    Pedro de Sousa Gomes

    2012-03-01

    Full Text Available Objectives: The purpose of present paper is to critically address the recent advances on diagnostic procedures of Sjögren’s syndrome, taking into account the attained local and systemic features of the disease. Material and Methods: A comprehensive review of the available literature regarding to the diagnostic approaches to Sjögren’s syndrome was conducted. Eligible studies were identified by searching the electronic literature PubMed, Medline, Embase, and ScienceDirect databases for relevant reports (last search update January 2012 combining the MESH heading term “Sjögren’s syndrome”, with the words "diagnosis, diagnostic procedures, salivary gland function, ocular tests, histopathology, salivary gland imaging, serology". The authors checked the references of the selected articles to identify additional eligible publications and contacted the authors, if necessary. Results: Presented article addresses the established diagnostic criteria for Sjögren’s syndrome and critically evaluates the most commonly used diagnostic procedures, presenting data from author’s own clinical experience. Diagnostic criteria for Sjögren’s syndrome are required both by healthcare professionals and patients, namely in order to provide a rational basis for the assessment of the symptoms, establish an individual disease prognosis, and orientate the therapeutic intervention. Conclusions: Sjögren’s syndrome is quite a common autoimmune disease of which the diagnosis and treatment are not easily established. Due to its systemic involvement, it can exhibit a wide range of clinical manifestations that contribute to confusion and delay in diagnosis. The use of proper diagnostic modalities will help to reduce the time to diagnosis and preserve the health and quality of life of patients with Sjögren’s syndrome.

  4. A Pedagogical approach of schistosomiasis an experience in health education in Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Cristiano Lara Massara

    2004-08-01

    Full Text Available The experience described here is part of an extensive program that aims to stimulate schools to develop health integrated projects from theme generators, i.e., themes that have a meaning for the community. It was developed in Jaboticatubas, a town in the metropolitan region of Belo Horizonte, capital of the state of Minas Gerais, Brazil, and the focus was schistosomiasis. The selection was based on the expressive and historical prevalence of this disease in the county, which has been known as the "capital of schistosomiasis", in a national press release since the 1960's. Schistosomiasis is also a theme pointed out by teachers as requiring more information and methodologies to work with their students, most of them living in areas of high risk of transmission. In addition, during the last years, this disease has been transmitted silently through an increasing rural tourism in that region, requiring integrated and effective control actions. The developed strategy included four schools, whose teachers, students, and families took part in the process. It emphasizes in a critical pedagogy approach, which focuses on health issues as themes that may mobilize the school community and awake the population to a work which integrates environment, health, and citizenship. The results demonstrate that teachers and students not only acquired new knowledge and methodological skills, but also gained confidence in their ability to improve their health conditions. Thus, the project promotes a critical education that can result a more permanent effect on the control of schistosomiasis as well as other benefits for the schools and for the population.

  5. A Pedagogical approach of schistosomiasis -- an experience in health education in Minas Gerais, Brazil.

    Science.gov (United States)

    Massara, Cristiano Lara; Schall, Virgínia Torres

    2004-01-01

    The experience described here is part of an extensive program that aims to stimulate schools to develop health integrated projects from theme generators, i.e., themes that have a meaning for the community. It was developed in Jaboticatubas, a town in the metropolitan region of Belo Horizonte, capital of the state of Minas Gerais, Brazil, and the focus was schistosomiasis. The selection was based on the expressive and historical prevalence of this disease in the county, which has been known as the "capital of schistosomiasis", in a national press release since the 1960's. Schistosomiasis is also a theme pointed out by teachers as requiring more information and methodologies to work with their students, most of them living in areas of high risk of transmission. In addition, during the last years, this disease has been transmitted silently through an increasing rural tourism in that region, requiring integrated and effective control actions. The developed strategy included four schools, whose teachers, students, and families took part in the process. It emphasizes in a critical pedagogy approach, which focuses on health issues as themes that may mobilize the school community and awake the population to a work which integrates environment, health, and citizenship. The results demonstrate that teachers and students not only acquired new knowledge and methodological skills, but also gained confidence in their ability to improve their health conditions. Thus, the project promotes a critical education that can result a more permanent effect on the control of schistosomiasis as well as other benefits for the schools and for the population.

  6. A normative inference approach for optimal sample sizes in decisions from experience

    Science.gov (United States)

    Ostwald, Dirk; Starke, Ludger; Hertwig, Ralph

    2015-01-01

    “Decisions from experience” (DFE) refers to a body of work that emerged in research on behavioral decision making over the last decade. One of the major experimental paradigms employed to study experience-based choice is the “sampling paradigm,” which serves as a model of decision making under limited knowledge about the statistical structure of the world. In this paradigm respondents are presented with two payoff distributions, which, in contrast to standard approaches in behavioral economics, are specified not in terms of explicit outcome-probability information, but by the opportunity to sample outcomes from each distribution without economic consequences. Participants are encouraged to explore the distributions until they feel confident enough to decide from which they would prefer to draw from in a final trial involving real monetary payoffs. One commonly employed measure to characterize the behavior of participants in the sampling paradigm is the sample size, that is, the number of outcome draws which participants choose to obtain from each distribution prior to terminating sampling. A natural question that arises in this context concerns the “optimal” sample size, which could be used as a normative benchmark to evaluate human sampling behavior in DFE. In this theoretical study, we relate the DFE sampling paradigm to the classical statistical decision theoretic literature and, under a probabilistic inference assumption, evaluate optimal sample sizes for DFE. In our treatment we go beyond analytically established results by showing how the classical statistical decision theoretic framework can be used to derive optimal sample sizes under arbitrary, but numerically evaluable, constraints. Finally, we critically evaluate the value of deriving optimal sample sizes under this framework as testable predictions for the experimental study of sampling behavior in DFE. PMID:26441720

  7. A divide and conquer approach to determine the Pareto frontier for optimization of protein engineering experiments

    Science.gov (United States)

    He, Lu; Friedman, Alan M.; Bailey-Kellogg, Chris

    2016-01-01

    In developing improved protein variants by site-directed mutagenesis or recombination, there are often competing objectives that must be considered in designing an experiment (selecting mutations or breakpoints): stability vs. novelty, affinity vs. specificity, activity vs. immunogenicity, and so forth. Pareto optimal experimental designs make the best trade-offs between competing objectives. Such designs are not “dominated”; i.e., no other design is better than a Pareto optimal design for one objective without being worse for another objective. Our goal is to produce all the Pareto optimal designs (the Pareto frontier), in order to characterize the trade-offs and suggest designs most worth considering, but to avoid explicitly considering the large number of dominated designs. To do so, we develop a divide-and-conquer algorithm, PEPFR (Protein Engineering Pareto FRontier), that hierarchically subdivides the objective space, employing appropriate dynamic programming or integer programming methods to optimize designs in different regions. This divide-and-conquer approach is efficient in that the number of divisions (and thus calls to the optimizer) is directly proportional to the number of Pareto optimal designs. We demonstrate PEPFR with three protein engineering case studies: site-directed recombination for stability and diversity via dynamic programming, site-directed mutagenesis of interacting proteins for affinity and specificity via integer programming, and site-directed mutagenesis of a therapeutic protein for activity and immunogenicity via integer programming. We show that PEPFR is able to effectively produce all the Pareto optimal designs, discovering many more designs than previous methods. The characterization of the Pareto frontier provides additional insights into the local stability of design choices as well as global trends leading to trade-offs between competing criteria. PMID:22180081

  8. Drought resilience across ecologically dominant species: An experiment-model integration approach

    Science.gov (United States)

    Felton, A. J.; Warren, J.; Ricciuto, D. M.; Smith, M. D.

    2017-12-01

    Poorly understood are the mechanisms contributing to variability in ecosystem recovery following drought. Grasslands of the central U.S. are ecologically and economically important ecosystems, yet are also highly sensitive to drought. Although characteristics of these ecosystems change across gradients of temperature and precipitation, a consistent feature among these systems is the presence of highly abundant, dominant grass species that control biomass production. As a result, the incorporation of these species' traits into terrestrial biosphere models may constrain predictions amid increases in climatic variability. Here we report the results of a modeling-experiment (MODEX) research approach. We investigated the physiological, morphological and growth responses of the dominant grass species from each of the four major grasslands of the central U.S. (ranging from tallgrass prairie to desert grassland) following severe drought. Despite significant differences in baseline values, full recovery in leaf physiological function was evident across species, of which was consistently driven by the production of new leaves. Further, recovery in whole-plant carbon uptake tended to be driven by shifts in allocation from belowground to aboveground structures. However, there was clear variability among species in the magnitude of this dynamic as well as the relative allocation to stem versus leaf production. As a result, all species harbored the physiological capacity to recover from drought, yet we posit that variability in the recovery of whole-plant carbon uptake to be more strongly driven by variability in the sensitivity of species' morphology to soil moisture increases. The next step of this project will be to incorporate these and other existing data on these species and ecosystems into the community land model in an effort to test the sensitivity of this model to these data.

  9. Curved sensors for compact high-resolution wide-field designs: prototype demonstration and optical characterization

    Science.gov (United States)

    Chambion, Bertrand; Gaschet, Christophe; Behaghel, Thibault; Vandeneynde, Aurélie; Caplet, Stéphane; Gétin, Stéphane; Henry, David; Hugot, Emmanuel; Jahn, Wilfried; Lombardo, Simona; Ferrari, Marc

    2018-02-01

    Over the recent years, a huge interest has grown for curved electronics, particularly for opto-electronics systems. Curved sensors help the correction of off-axis aberrations, such as Petzval Field Curvature, astigmatism, and bring significant optical and size benefits for imaging systems. In this paper, we first describe advantages of curved sensor and associated packaging process applied on a 1/1.8'' format 1.3Mpx global shutter CMOS sensor (Teledyne EV76C560) into its standard ceramic package with a spherical radius of curvature Rc=65mm and 55mm. The mechanical limits of the die are discussed (Finite Element Modelling and experimental), and electro-optical performances are investigated. Then, based on the monocentric optical architecture, we proposed a new design, compact and with a high resolution, developed specifically for a curved image sensor including optical optimization, tolerances, assembly and optical tests. Finally, a functional prototype is presented through a benchmark approach and compared to an existing standard optical system with same performances and a x2.5 reduction of length. The finality of this work was a functional prototype demonstration on the CEA-LETI during Photonics West 2018 conference. All these experiments and optical results demonstrate the feasibility and high performances of systems with curved sensors.

  10. Spherical images and inextensible curved folding

    Science.gov (United States)

    Seffen, Keith A.

    2018-02-01

    In their study, Duncan and Duncan [Proc. R. Soc. London A 383, 191 (1982), 10.1098/rspa.1982.0126] calculate the shape of an inextensible surface folded in two about a general curve. They find the analytical relationships between pairs of generators linked across the fold curve, the shape of the original path, and the fold angle variation along it. They present two special cases of generator layouts for which the fold angle is uniform or the folded curve remains planar, for simplifying practical folding in sheet-metal processes. We verify their special cases by a graphical treatment according to a method of Gauss. We replace the fold curve by a piecewise linear path, which connects vertices of intersecting pairs of hinge lines. Inspired by the d-cone analysis by Farmer and Calladine [Int. J. Mech. Sci. 47, 509 (2005), 10.1016/j.ijmecsci.2005.02.013], we construct the spherical images for developable folding of successive vertices: the operating conditions of the special cases in Duncan and Duncan are then revealed straightforwardly by the geometric relationships between the images. Our approach may be used to synthesize folding patterns for novel deployable and shape-changing surfaces without need of complex calculation.

  11. Self-assessment as an approach to improvement of efficient implementation of Ukrainian NPP operational experience

    International Nuclear Information System (INIS)

    Pecheritsya, L.M.; Lyigots'kij, O.Yi.; Pecheritsya, O.V.; Tarasenko, V.M.

    2012-01-01

    the paper contains a brief description of the procedure for implementation of operational experience, focuses on the role of self -assessment in efficient use of operational experience, presents a review of international and national practices of self-assessment and review of the main features, issues and ways to improve self-assessment of efficient use of operational experience in Ukraine

  12. Sustainable Development Impacts of NAMAs: An integrated approach to assessment of co-benefits based on experience with the CDM

    DEFF Research Database (Denmark)

    Olsen, Karen Holm

    to assess the SD impacts of NAMAs. This paper argues for a new integrated approach to asses NAMAs' SD impacts that consists of SD indicators, procedures for stakeholder involvement and safeguards against negative impacts. The argument is based on a review of experience with the CDM’s contribution to SD...... and a comparison of similarities and differences between NAMAs and CDM. Five elements of a new approach towards assessment of NAMAs SD impacts are suggested based on emerging approaches and methodologies for monitoring, reporting and verification (MRV) of greenhouse gas reductions and SD impacts of NAMAs....

  13. Computational aspects of algebraic curves

    CERN Document Server

    Shaska, Tanush

    2005-01-01

    The development of new computational techniques and better computing power has made it possible to attack some classical problems of algebraic geometry. The main goal of this book is to highlight such computational techniques related to algebraic curves. The area of research in algebraic curves is receiving more interest not only from the mathematics community, but also from engineers and computer scientists, because of the importance of algebraic curves in applications including cryptography, coding theory, error-correcting codes, digital imaging, computer vision, and many more.This book cove

  14. Educational analysis of a first year engineering physics experiment on standing waves: based on the ACELL approach

    International Nuclear Information System (INIS)

    Bhathal, Ragbir; Sharma, Manjula D; Mendez, Alberto

    2010-01-01

    This paper describes an educational analysis of a first year physics experiment on standing waves for engineering students. The educational analysis is based on the ACELL (Advancing Chemistry by Enhancing Learning in the Laboratory) approach which includes a statement of educational objectives and an analysis of student learning experiences. The experiment is likely to be found in many physics departments, hence is appropriate to illustrate the ACELL approach in physics. The concepts associated with standing waves are difficult; however, they are underpinned by mathematical formulation which lend themselves to be visualized in experiments. The challenge is to strike a balance between these two for the particular student cohort. In this study, this balance is achieved by using simple equipment and providing appropriate scaffolds for students to associate abstract concepts with concrete visuals. In essence the experiment is designed to adequately manage cognitive resources. Students work in pairs and are questioned and assisted by demonstrators and academic staff during a 2 h practical class. Students were surveyed using the ACELL instrument. Analysis of the data showed that by completing the practical students felt that their understanding of physics had increased. Furthermore, students could see the relevance of this experiment to their engineering studies and that it provided them with an opportunity to take responsibility for their own learning. Overall they had a positive learning experience. In short there is a lot of dividend from a small outlay of resources.

  15. Understanding Black Male Student Athletes' Experiences at a Historically Black College/University: A Mixed Methods Approach

    Science.gov (United States)

    Cooper, Joseph N.; Hall, Jori

    2016-01-01

    The purpose of this article is to describe how a mixed methods approach was employed to acquire a better understanding of Black male student athletes' experiences at a historically Black college/university in the southeastern United States. A concurrent triangulation design was incorporated to allow different data sources to be collected and…

  16. The Lived Experiences of Vice Presidents for Student Affairs: A Study Exploring How Social Identity Impacts Leadership Approach

    Science.gov (United States)

    Jones, David E.

    2016-01-01

    This study aimed to both draw awareness and increase understanding of how lived experiences across race, gender and sexual orientation social identities impact the leadership approach of Vice Presidents for Student Affairs. As the student demographic becomes increasingly more diverse on college and university campuses, higher education leaders…

  17. Learning Experiences and Practices of Elementary Teacher Candidates on the Use of Emerging Technology: A Grounded Theory Approach

    Science.gov (United States)

    Bahng, EunJin; Lee, Mimi

    2017-01-01

    The purpose of this study is to understand the phenomenon of the "professional journey" of elementary teacher candidates (ETC) both as learners and as teachers by exploring their learning experiences and practices regarding the virtual reality (VR) platform called Second Life (SL). Using the grounded theory approach, we designed an…

  18. Returning to the Richness of Experience: Is Autoethnography a Useful Approach for Outdoor Educators in Promoting Pro-Environmental Behaviour?

    Science.gov (United States)

    Nicol, Robbie

    2013-01-01

    The use of autoethnography in social science research is becoming increasingly popular. The potential this research approach might offer to the theory and practice of outdoor education has yet to be fully examined. In this paper, autoethnography is used to explore some personal accounts of my own outdoor experiences from which I derive distinctive…

  19. 51Cr - erythrocyte survival curves

    International Nuclear Information System (INIS)

    Paiva Costa, J. de.

    1982-07-01

    Sixteen patients were studied, being fifteen patients in hemolytic state, and a normal individual as a witness. The aim was to obtain better techniques for the analysis of the erythrocytes, survival curves, according to the recommendations of the International Committee of Hematology. It was used the radiochromatic method as a tracer. Previously a revisional study of the International Literature was made in its aspects inherent to the work in execution, rendering possible to establish comparisons and clarify phonomena observed in cur investigation. Several parameters were considered in this study, hindering both the exponential and the linear curves. The analysis of the survival curves of the erythrocytes in the studied group, revealed that the elution factor did not present a homogeneous answer quantitatively to all, though, the result of the analysis of these curves have been established, through listed programs in the electronic calculator. (Author) [pt

  20. Melting curves of gammairradiated DNA

    International Nuclear Information System (INIS)

    Hofer, H.; Altmann, H.; Kehrer, M.

    1978-08-01

    Melting curves of gammairradiated DNA and data derived of them, are reported. The diminished stability is explained by basedestruction. DNA denatures completely at room temperature, if at least every fifth basepair is broken or weakened by irradiation. (author)