WorldWideScience

Sample records for stratified quota sampling

  1. Quota sampling in internet research: practical issues.

    Science.gov (United States)

    Im, Eun-Ok; Chee, Wonshik

    2011-07-01

    Quota sampling has been suggested as a potentially good method for Internet-based research and has been used by several researchers working with Internet samples. However, very little is known about the issues or concerns in using a quota sampling method in Internet research. The purpose of this article was to present the practical issues using quota sampling in an Internet-based study. During the Internet study, the research team recorded all recruitment issues that arose and made written notes indicating the possible reasons for the problems. In addition, biweekly team discussions were conducted for which written records were kept. Overall, quota sampling was effective in ensuring that an adequate number of midlife women were recruited from the targeted ethnic groups. However, during the study process, we encountered the following practical issues using quota sampling: (1) difficulty reaching out to women in lower socioeconomic classes, (2) difficulty ensuring authenticity of participants' identities, (3) participants giving inconsistent answers for the screening questions versus the Internet survey questions, (4) potential problems with a question on socioeconomic status, (5) resentment toward the research project and/or researchers because of rejection, and (6) a longer time and more expense than anticipated.

  2. Bayesian stratified sampling to assess corpus utility

    Energy Technology Data Exchange (ETDEWEB)

    Hochberg, J.; Scovel, C.; Thomas, T.; Hall, S.

    1998-12-01

    This paper describes a method for asking statistical questions about a large text corpus. The authors exemplify the method by addressing the question, ``What percentage of Federal Register documents are real documents, of possible interest to a text researcher or analyst?`` They estimate an answer to this question by evaluating 200 documents selected from a corpus of 45,820 Federal Register documents. Bayesian analysis and stratified sampling are used to reduce the sampling uncertainty of the estimate from over 3,100 documents to fewer than 1,000. A possible application of the method is to establish baseline statistics used to estimate recall rates for information retrieval systems.

  3. Stratified sampling design based on data mining.

    Science.gov (United States)

    Kim, Yeonkook J; Oh, Yoonhwan; Park, Sunghoon; Cho, Sungzoon; Park, Hayoung

    2013-09-01

    To explore classification rules based on data mining methodologies which are to be used in defining strata in stratified sampling of healthcare providers with improved sampling efficiency. We performed k-means clustering to group providers with similar characteristics, then, constructed decision trees on cluster labels to generate stratification rules. We assessed the variance explained by the stratification proposed in this study and by conventional stratification to evaluate the performance of the sampling design. We constructed a study database from health insurance claims data and providers' profile data made available to this study by the Health Insurance Review and Assessment Service of South Korea, and population data from Statistics Korea. From our database, we used the data for single specialty clinics or hospitals in two specialties, general surgery and ophthalmology, for the year 2011 in this study. Data mining resulted in five strata in general surgery with two stratification variables, the number of inpatients per specialist and population density of provider location, and five strata in ophthalmology with two stratification variables, the number of inpatients per specialist and number of beds. The percentages of variance in annual changes in the productivity of specialists explained by the stratification in general surgery and ophthalmology were 22% and 8%, respectively, whereas conventional stratification by the type of provider location and number of beds explained 2% and 0.2% of variance, respectively. This study demonstrated that data mining methods can be used in designing efficient stratified sampling with variables readily available to the insurer and government; it offers an alternative to the existing stratification method that is widely used in healthcare provider surveys in South Korea.

  4. Monte Carlo stratified source-sampling

    International Nuclear Information System (INIS)

    Blomquist, R.N.; Gelbard, E.M.

    1997-01-01

    In 1995, at a conference on criticality safety, a special session was devoted to the Monte Carlo open-quotes eigenvalue of the worldclose quotes problem. Argonne presented a paper, at that session, in which the anomalies originally observed in that problem were reproduced in a much simplified model-problem configuration, and removed by a version of stratified source-sampling. The original test-problem was treated by a special code designed specifically for that purpose. Recently ANL started work on a method for dealing with more realistic eigenvalue of the world configurations, and has been incorporating this method into VIM. The original method has been modified to take into account real-world statistical noise sources not included in the model problem. This paper constitutes a status report on work still in progress

  5. Stratified source-sampling techniques for Monte Carlo eigenvalue analysis

    International Nuclear Information System (INIS)

    Mohamed, A.

    1998-01-01

    In 1995, at a conference on criticality safety, a special session was devoted to the Monte Carlo ''Eigenvalue of the World'' problem. Argonne presented a paper, at that session, in which the anomalies originally observed in that problem were reproduced in a much simplified model-problem configuration, and removed by a version of stratified source-sampling. In this paper, stratified source-sampling techniques are generalized and applied to three different Eigenvalue of the World configurations which take into account real-world statistical noise sources not included in the model problem, but which differ in the amount of neutronic coupling among the constituents of each configuration. It is concluded that, in Monte Carlo eigenvalue analysis of loosely-coupled arrays, the use of stratified source-sampling reduces the probability of encountering an anomalous result over that if conventional source-sampling methods are used. However, this gain in reliability is substantially less than that observed in the model-problem results

  6. Temporally stratified sampling programs for estimation of fish impingement

    International Nuclear Information System (INIS)

    Kumar, K.D.; Griffith, J.S.

    1977-01-01

    Impingement monitoring programs often expend valuable and limited resources and fail to provide a dependable estimate of either total annual impingement or those biological and physicochemical factors affecting impingement. In situations where initial monitoring has identified ''problem'' fish species and the periodicity of their impingement, intensive sampling during periods of high impingement will maximize information obtained. We use data gathered at two nuclear generating facilities in the southeastern United States to discuss techniques of designing such temporally stratified monitoring programs and their benefits and drawbacks. Of the possible temporal patterns in environmental factors within a calendar year, differences among seasons are most influential in the impingement of freshwater fishes in the Southeast. Data on the threadfin shad (Dorosoma petenense) and the role of seasonal temperature changes are utilized as an example to demonstrate ways of most efficiently and accurately estimating impingement of the species

  7. Distribution-Preserving Stratified Sampling for Learning Problems.

    Science.gov (United States)

    Cervellera, Cristiano; Maccio, Danilo

    2017-06-09

    The need for extracting a small sample from a large amount of real data, possibly streaming, arises routinely in learning problems, e.g., for storage, to cope with computational limitations, obtain good training/test/validation sets, and select minibatches for stochastic gradient neural network training. Unless we have reasons to select the samples in an active way dictated by the specific task and/or model at hand, it is important that the distribution of the selected points is as similar as possible to the original data. This is obvious for unsupervised learning problems, where the goal is to gain insights on the distribution of the data, but it is also relevant for supervised problems, where the theory explains how the training set distribution influences the generalization error. In this paper, we analyze the technique of stratified sampling from the point of view of distances between probabilities. This allows us to introduce an algorithm, based on recursive binary partition of the input space, aimed at obtaining samples that are distributed as much as possible as the original data. A theoretical analysis is proposed, proving the (greedy) optimality of the procedure together with explicit error bounds. An adaptive version of the algorithm is also introduced to cope with streaming data. Simulation tests on various data sets and different learning tasks are also provided.

  8. Prototypic Features of Loneliness in a Stratified Sample of Adolescents

    Directory of Open Access Journals (Sweden)

    Mathias Lasgaard

    2009-06-01

    Full Text Available Dominant theoretical approaches in loneliness research emphasize the value of personality characteristics in explaining loneliness. The present study examines whether dysfunctional social strategies and attributions in lonely adolescents can be explained by personality characteristics. A questionnaire survey was conducted with 379 Danish Grade 8 students (M = 14.1 years, SD = 0.4 from 22 geographically stratified and randomly selected schools. Hierarchical linear regression analysis showed that network orientation, success expectation and avoidance in affiliative situations predicted loneliness independent of personality characteristics, demographics and social desirability. The study indicates that dysfunctional strategies and attributions in affiliative situations are directly related to loneliness in adolescence. These strategies and attributions may preclude lonely adolescents from guidance and intervention. Thus, professionals need to be knowledgeable about prototypic features of loneliness in addition to employing a pro-active approach when assisting adolescents who display prototypic features.

  9. Textiles Quotas

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Shanghai launched China’s first electronic trading platform for textiles export licenses yesterday, allowing firms to easily sell or buy quotas. The platform (www.e-tj.cn) is aimed at raising efficiency and curb-

  10. Tobacco smoking surveillance: is quota sampling an efficient tool for monitoring national trends? A comparison with a random cross-sectional survey.

    Directory of Open Access Journals (Sweden)

    Romain Guignard

    Full Text Available OBJECTIVES: It is crucial for policy makers to monitor the evolution of tobacco smoking prevalence. In France, this monitoring is based on a series of cross-sectional general population surveys, the Health Barometers, conducted every five years and based on random samples. A methodological study has been carried out to assess the reliability of a monitoring system based on regular quota sampling surveys for smoking prevalence. DESIGN / OUTCOME MEASURES: In 2010, current and daily tobacco smoking prevalences obtained in a quota survey on 8,018 people were compared with those of the 2010 Health Barometer carried out on 27,653 people. Prevalences were assessed separately according to the telephone equipment of the interviewee (landline phone owner vs "mobile-only", and logistic regressions were conducted in the pooled database to assess the impact of the telephone equipment and of the survey mode on the prevalences found. Finally, logistic regressions adjusted for sociodemographic characteristics were conducted in the random sample in order to determine the impact of the needed number of calls to interwiew "hard-to-reach" people on the prevalence found. RESULTS: Current and daily prevalences were higher in the random sample (respectively 33.9% and 27.5% in 15-75 years-old than in the quota sample (respectively 30.2% and 25.3%. In both surveys, current and daily prevalences were lower among landline phone owners (respectively 31.8% and 25.5% in the random sample and 28.9% and 24.0% in the quota survey. The required number of calls was slightly related to the smoking status after adjustment for sociodemographic characteristics. CONCLUSION: Random sampling appears to be more effective than quota sampling, mainly by making it possible to interview hard-to-reach populations.

  11. Estimation of Finite Population Mean in Multivariate Stratified Sampling under Cost Function Using Goal Programming

    Directory of Open Access Journals (Sweden)

    Atta Ullah

    2014-01-01

    Full Text Available In practical utilization of stratified random sampling scheme, the investigator meets a problem to select a sample that maximizes the precision of a finite population mean under cost constraint. An allocation of sample size becomes complicated when more than one characteristic is observed from each selected unit in a sample. In many real life situations, a linear cost function of a sample size nh is not a good approximation to actual cost of sample survey when traveling cost between selected units in a stratum is significant. In this paper, sample allocation problem in multivariate stratified random sampling with proposed cost function is formulated in integer nonlinear multiobjective mathematical programming. A solution procedure is proposed using extended lexicographic goal programming approach. A numerical example is presented to illustrate the computational details and to compare the efficiency of proposed compromise allocation.

  12. Unit Stratified Sampling as a Tool for Approximation of Stochastic Optimization Problems

    Czech Academy of Sciences Publication Activity Database

    Šmíd, Martin

    2012-01-01

    Roč. 19, č. 30 (2012), s. 153-169 ISSN 1212-074X R&D Projects: GA ČR GAP402/11/0150; GA ČR GAP402/10/0956; GA ČR GA402/09/0965 Institutional research plan: CEZ:AV0Z10750506 Institutional support: RVO:67985556 Keywords : Stochastic programming * approximation * stratified sampling Subject RIV: BB - Applied Statistics, Operational Research http://library.utia.cas.cz/separaty/2013/E/smid-unit stratified sampling as a tool for approximation of stochastic optimization problems.pdf

  13. CBP Quota Bulletins

    Data.gov (United States)

    Department of Homeland Security — Quota information is issued for the trade community by the Quota Enforcement Administration Branch within the Office of International Trade. The Quota Bulletins have...

  14. Fixed-location hydroacoustic monitoring designs for estimating fish passage using stratified random and systematic sampling

    International Nuclear Information System (INIS)

    Skalski, J.R.; Hoffman, A.; Ransom, B.H.; Steig, T.W.

    1993-01-01

    Five alternate sampling designs are compared using 15 d of 24-h continuous hydroacoustic data to identify the most favorable approach to fixed-location hydroacoustic monitoring of salmonid outmigrants. Four alternative aproaches to systematic sampling are compared among themselves and with stratified random sampling (STRS). Stratifying systematic sampling (STSYS) on a daily basis is found to reduce sampling error in multiday monitoring studies. Although sampling precision was predictable with varying levels of effort in STRS, neither magnitude nor direction of change in precision was predictable when effort was varied in systematic sampling (SYS). Furthermore, modifying systematic sampling to include replicated (e.g., nested) sampling (RSYS) is further shown to provide unbiased point and variance estimates as does STRS. Numerous short sampling intervals (e.g., 12 samples of 1-min duration per hour) must be monitored hourly using RSYS to provide efficient, unbiased point and interval estimates. For equal levels of effort, STRS outperformed all variations of SYS examined. Parametric approaches to confidence interval estimates are found to be superior to nonparametric interval estimates (i.e., bootstrap and jackknife) in estimating total fish passage. 10 refs., 1 fig., 8 tabs

  15. [Study of spatial stratified sampling strategy of Oncomelania hupensis snail survey based on plant abundance].

    Science.gov (United States)

    Xun-Ping, W; An, Z

    2017-07-27

    Objective To optimize and simplify the survey method of Oncomelania hupensis snails in marshland endemic regions of schistosomiasis, so as to improve the precision, efficiency and economy of the snail survey. Methods A snail sampling strategy (Spatial Sampling Scenario of Oncomelania based on Plant Abundance, SOPA) which took the plant abundance as auxiliary variable was explored and an experimental study in a 50 m×50 m plot in a marshland in the Poyang Lake region was performed. Firstly, the push broom surveyed data was stratified into 5 layers by the plant abundance data; then, the required numbers of optimal sampling points of each layer through Hammond McCullagh equation were calculated; thirdly, every sample point in the line with the Multiple Directional Interpolation (MDI) placement scheme was pinpointed; and finally, the comparison study among the outcomes of the spatial random sampling strategy, the traditional systematic sampling method, the spatial stratified sampling method, Sandwich spatial sampling and inference and SOPA was performed. Results The method (SOPA) proposed in this study had the minimal absolute error of 0.213 8; and the traditional systematic sampling method had the largest estimate, and the absolute error was 0.924 4. Conclusion The snail sampling strategy (SOPA) proposed in this study obtains the higher estimation accuracy than the other four methods.

  16. Monitoring oil persistence on beaches : SCAT versus stratified random sampling designs

    International Nuclear Information System (INIS)

    Short, J.W.; Lindeberg, M.R.; Harris, P.M.; Maselko, J.M.; Pella, J.J.; Rice, S.D.

    2003-01-01

    In the event of a coastal oil spill, shoreline clean-up assessment teams (SCAT) commonly rely on visual inspection of the entire affected area to monitor the persistence of the oil on beaches. Occasionally, pits are excavated to evaluate the persistence of subsurface oil. This approach is practical for directing clean-up efforts directly following a spill. However, sampling of the 1989 Exxon Valdez oil spill in Prince William Sound 12 years later has shown that visual inspection combined with pit excavation does not offer estimates of contaminated beach area of stranded oil volumes. This information is needed to statistically evaluate the significance of change with time. Assumptions regarding the correlation of visually-evident surface oil and cryptic subsurface oil are usually not evaluated as part of the SCAT mandate. Stratified random sampling can avoid such problems and could produce precise estimates of oiled area and volume that allow for statistical assessment of major temporal trends and the extent of the impact. The 2001 sampling of the shoreline of Prince William Sound showed that 15 per cent of surface oil occurrences were associated with subsurface oil. This study demonstrates the usefulness of the stratified random sampling method and shows how sampling design parameters impact statistical outcome. Power analysis based on the study results, indicate that optimum power is derived when unnecessary stratification is avoided. It was emphasized that sampling effort should be balanced between choosing sufficient beaches for sampling and the intensity of sampling

  17. Data splitting for artificial neural networks using SOM-based stratified sampling.

    Science.gov (United States)

    May, R J; Maier, H R; Dandy, G C

    2010-03-01

    Data splitting is an important consideration during artificial neural network (ANN) development where hold-out cross-validation is commonly employed to ensure generalization. Even for a moderate sample size, the sampling methodology used for data splitting can have a significant effect on the quality of the subsets used for training, testing and validating an ANN. Poor data splitting can result in inaccurate and highly variable model performance; however, the choice of sampling methodology is rarely given due consideration by ANN modellers. Increased confidence in the sampling is of paramount importance, since the hold-out sampling is generally performed only once during ANN development. This paper considers the variability in the quality of subsets that are obtained using different data splitting approaches. A novel approach to stratified sampling, based on Neyman sampling of the self-organizing map (SOM), is developed, with several guidelines identified for setting the SOM size and sample allocation in order to minimize the bias and variance in the datasets. Using an example ANN function approximation task, the SOM-based approach is evaluated in comparison to random sampling, DUPLEX, systematic stratified sampling, and trial-and-error sampling to minimize the statistical differences between data sets. Of these approaches, DUPLEX is found to provide benchmark performance with good model performance, with no variability. The results show that the SOM-based approach also reliably generates high-quality samples and can therefore be used with greater confidence than other approaches, especially in the case of non-uniform datasets, with the benefit of scalability to perform data splitting on large datasets. Copyright 2009 Elsevier Ltd. All rights reserved.

  18. MUP, CEC-DES, STRADE. Codes for uncertainty propagation, experimental design and stratified random sampling techniques

    International Nuclear Information System (INIS)

    Amendola, A.; Astolfi, M.; Lisanti, B.

    1983-01-01

    The report describes the how-to-use of the codes: MUP (Monte Carlo Uncertainty Propagation) for uncertainty analysis by Monte Carlo simulation, including correlation analysis, extreme value identification and study of selected ranges of the variable space; CEC-DES (Central Composite Design) for building experimental matrices according to the requirements of Central Composite and Factorial Experimental Designs; and, STRADE (Stratified Random Design) for experimental designs based on the Latin Hypercube Sampling Techniques. Application fields, of the codes are probabilistic risk assessment, experimental design, sensitivity analysis and system identification problems

  19. Brachytherapy dose-volume histogram computations using optimized stratified sampling methods

    International Nuclear Information System (INIS)

    Karouzakis, K.; Lahanas, M.; Milickovic, N.; Giannouli, S.; Baltas, D.; Zamboglou, N.

    2002-01-01

    A stratified sampling method for the efficient repeated computation of dose-volume histograms (DVHs) in brachytherapy is presented as used for anatomy based brachytherapy optimization methods. The aim of the method is to reduce the number of sampling points required for the calculation of DVHs for the body and the PTV. From the DVHs are derived the quantities such as Conformity Index COIN and COIN integrals. This is achieved by using partial uniform distributed sampling points with a density in each region obtained from a survey of the gradients or the variance of the dose distribution in these regions. The shape of the sampling regions is adapted to the patient anatomy and the shape and size of the implant. For the application of this method a single preprocessing step is necessary which requires only a few seconds. Ten clinical implants were used to study the appropriate number of sampling points, given a required accuracy for quantities such as cumulative DVHs, COIN indices and COIN integrals. We found that DVHs of very large tissue volumes surrounding the PTV, and also COIN distributions, can be obtained using a factor of 5-10 times smaller the number of sampling points in comparison with uniform distributed points

  20. A stratified two-stage sampling design for digital soil mapping in a Mediterranean basin

    Science.gov (United States)

    Blaschek, Michael; Duttmann, Rainer

    2015-04-01

    The quality of environmental modelling results often depends on reliable soil information. In order to obtain soil data in an efficient manner, several sampling strategies are at hand depending on the level of prior knowledge and the overall objective of the planned survey. This study focuses on the collection of soil samples considering available continuous secondary information in an undulating, 16 km²-sized river catchment near Ussana in southern Sardinia (Italy). A design-based, stratified, two-stage sampling design has been applied aiming at the spatial prediction of soil property values at individual locations. The stratification based on quantiles from density functions of two land-surface parameters - topographic wetness index and potential incoming solar radiation - derived from a digital elevation model. Combined with four main geological units, the applied procedure led to 30 different classes in the given test site. Up to six polygons of each available class were selected randomly excluding those areas smaller than 1ha to avoid incorrect location of the points in the field. Further exclusion rules were applied before polygon selection masking out roads and buildings using a 20m buffer. The selection procedure was repeated ten times and the set of polygons with the best geographical spread were chosen. Finally, exact point locations were selected randomly from inside the chosen polygon features. A second selection based on the same stratification and following the same methodology (selecting one polygon instead of six) was made in order to create an appropriate validation set. Supplementary samples were obtained during a second survey focusing on polygons that have either not been considered during the first phase at all or were not adequately represented with respect to feature size. In total, both field campaigns produced an interpolation set of 156 samples and a validation set of 41 points. The selection of sample point locations has been done using

  1. Gambling problems in the family – A stratified probability sample study of prevalence and reported consequences

    Directory of Open Access Journals (Sweden)

    Øren Anita

    2008-12-01

    Full Text Available Abstract Background Prior studies on the impact of problem gambling in the family mainly include help-seeking populations with small numbers of participants. The objective of the present stratified probability sample study was to explore the epidemiology of problem gambling in the family in the general population. Methods Men and women 16–74 years-old randomly selected from the Norwegian national population database received an invitation to participate in this postal questionnaire study. The response rate was 36.1% (3,483/9,638. Given the lack of validated criteria, two survey questions ("Have you ever noticed that a close relative spent more and more money on gambling?" and "Have you ever experienced that a close relative lied to you about how much he/she gambles?" were extrapolated from the Lie/Bet Screen for pathological gambling. Respondents answering "yes" to both questions were defined as Concerned Significant Others (CSOs. Results Overall, 2.0% of the study population was defined as CSOs. Young age, female gender, and divorced marital status were factors positively associated with being a CSO. CSOs often reported to have experienced conflicts in the family related to gambling, worsening of the family's financial situation, and impaired mental and physical health. Conclusion Problematic gambling behaviour not only affects the gambling individual but also has a strong impact on the quality of life of family members.

  2. Employment status, inflation and suicidal behaviour: an analysis of a stratified sample in Italy.

    Science.gov (United States)

    Solano, Paola; Pizzorno, Enrico; Gallina, Anna M; Mattei, Chiara; Gabrielli, Filippo; Kayman, Joshua

    2012-09-01

    There is abundant empirical evidence of a surplus risk of suicide among the unemployed, although few studies have investigated the influence of economic downturns on suicidal behaviours in an employment status-stratified sample. We investigated how economic inflation affected suicidal behaviours according to employment status in Italy from 2001 to 2008. Data concerning economically active people were provided by the Italian Institute for Statistical Analysis and by the International Monetary Fund. The association between inflation and completed versus attempted suicide with respect to employment status was investigated in every year and quarter-year of the study time frame. We considered three occupational categories: employed, unemployed who were previously employed and unemployed who had never worked. The unemployed are at higher suicide risk than the employed. Among the PE, a significant association between inflation and suicide attempt was found, whereas no association was reported concerning completed suicides. No association was found between completed and attempted suicides among the employed, the NE and inflation. Completed suicide in females is significantly associated with unemployment in every quarter-year. The reported vulnerability to suicidal behaviours among the PE as inflation rises underlines the need of effective support strategies for both genders in times of economic downturns.

  3. Stratified Sampling to Define Levels of Petrographic Variation in Coal Beds: Examples from Indonesia and New Zealand

    Directory of Open Access Journals (Sweden)

    Tim A. Moore

    2016-01-01

    Full Text Available DOI: 10.17014/ijog.3.1.29-51Stratified sampling of coal seams for petrographic analysis using block samples is a viable alternative to standard methods of channel sampling and particulate pellet mounts. Although petrographic analysis of particulate pellets is employed widely, it is both time consuming and does not allow variation within sampling units to be assessed - an important measure in any study whether it be for paleoenvironmental reconstruction or in obtaining estimates of industrial attributes. Also, samples taken as intact blocks provide additional information, such as texture and botanical affinity that cannot be gained using particulate pellets. Stratified sampling can be employed both on ‘fine’ and ‘coarse’ grained coal units. Fine-grained coals are defined as those coal intervals that do not contain vitrain bands greater than approximately 1 mm in thickness (as measured perpendicular to bedding. In fine-grained coal seams, a reasonable sized block sample (with a polished surface area of ~3 cm2 can be taken that encapsulates the macroscopic variability. However, for coarse-grained coals (vitrain bands >1 mm a different system has to be employed in order to accurately account for the larger particles. Macroscopic point counting of vitrain bands can accurately account for those particles>1 mm within a coal interval. This point counting method is conducted using something as simple as string on a coal face with marked intervals greater than the largest particle expected to be encountered (although new technologies are being developed to capture this type of information digitally. Comparative analyses of particulate pellets and blocks on the same interval show less than 6% variation between the two sample types when blocks are recalculated to include macroscopic counts of vitrain. Therefore even in coarse-grained coals, stratified sampling can be used effectively and representatively.

  4. Interactive Fuzzy Goal Programming approach in multi-response stratified sample surveys

    Directory of Open Access Journals (Sweden)

    Gupta Neha

    2016-01-01

    Full Text Available In this paper, we applied an Interactive Fuzzy Goal Programming (IFGP approach with linear, exponential and hyperbolic membership functions, which focuses on maximizing the minimum membership values to determine the preferred compromise solution for the multi-response stratified surveys problem, formulated as a Multi- Objective Non Linear Programming Problem (MONLPP, and by linearizing the nonlinear objective functions at their individual optimum solution, the problem is approximated to an Integer Linear Programming Problem (ILPP. A numerical example based on real data is given, and comparison with some existing allocations viz. Cochran’s compromise allocation, Chatterjee’s compromise allocation and Khowaja’s compromise allocation is made to demonstrate the utility of the approach.

  5. Discrete element method (DEM) simulations of stratified sampling during solid dosage form manufacturing.

    Science.gov (United States)

    Hancock, Bruno C; Ketterhagen, William R

    2011-10-14

    Discrete element model (DEM) simulations of the discharge of powders from hoppers under gravity were analyzed to provide estimates of dosage form content uniformity during the manufacture of solid dosage forms (tablets and capsules). For a system that exhibits moderate segregation the effects of sample size, number, and location within the batch were determined. The various sampling approaches were compared to current best-practices for sampling described in the Product Quality Research Institute (PQRI) Blend Uniformity Working Group (BUWG) guidelines. Sampling uniformly across the discharge process gave the most accurate results with respect to identifying segregation trends. Sigmoidal sampling (as recommended in the PQRI BUWG guidelines) tended to overestimate potential segregation issues, whereas truncated sampling (common in industrial practice) tended to underestimate them. The size of the sample had a major effect on the absolute potency RSD. The number of sampling locations (10 vs. 20) had very little effect on the trends in the data, and the number of samples analyzed at each location (1 vs. 3 vs. 7) had only a small effect for the sampling conditions examined. The results of this work provide greater understanding of the effect of different sampling approaches on the measured content uniformity of real dosage forms, and can help to guide the choice of appropriate sampling protocols. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. A census-weighted, spatially-stratified household sampling strategy for urban malaria epidemiology

    Directory of Open Access Journals (Sweden)

    Slutsker Laurence

    2008-02-01

    Full Text Available Abstract Background Urban malaria is likely to become increasingly important as a consequence of the growing proportion of Africans living in cities. A novel sampling strategy was developed for urban areas to generate a sample simultaneously representative of population and inhabited environments. Such a strategy should facilitate analysis of important epidemiological relationships in this ecological context. Methods Census maps and summary data for Kisumu, Kenya, were used to create a pseudo-sampling frame using the geographic coordinates of census-sampled structures. For every enumeration area (EA designated as urban by the census (n = 535, a sample of structures equal to one-tenth the number of households was selected. In EAs designated as rural (n = 32, a geographically random sample totalling one-tenth the number of households was selected from a grid of points at 100 m intervals. The selected samples were cross-referenced to a geographic information system, and coordinates transferred to handheld global positioning units. Interviewers found the closest eligible household to the sampling point and interviewed the caregiver of a child aged Results 4,336 interviews were completed in 473 of the 567 study area EAs from June 2002 through February 2003. EAs without completed interviews were randomly distributed, and non-response was approximately 2%. Mean distance from the assigned sampling point to the completed interview was 74.6 m, and was significantly less in urban than rural EAs, even when controlling for number of households. The selected sample had significantly more children and females of childbearing age than the general population, and fewer older individuals. Conclusion This method selected a sample that was simultaneously population-representative and inclusive of important environmental variation. The use of a pseudo-sampling frame and pre-programmed handheld GPS units is more efficient and may yield a more complete sample than

  7. Impact of Quota System and Catchment Area Policy on the University Admissions in North Central Nigeria

    Directory of Open Access Journals (Sweden)

    Joachim Chinweike Omeje

    2016-06-01

    Full Text Available The quota system and the catchment areas are federal government policies formulated to bridge the gap between the educationally developed states and the educationally less developed states. Sequel to the enactment of these policies, government established several universities across the country to create equal opportunity for all candidates. In spite of the astronomical growth of the universities in Nigeria, both the federal and the state governments have not been able to contend with the surging demand for the university education, hence the adoption of the quota system and catchment area policies. Serious concerns were expressed by relevant stakeholders on their perceived impact of the quota system and the catchment area on admissions into the federal and state universities in North Central Nigeria. This study therefore examined the impact of the quota system and catchment area policies on students’ admissions in North Central Nigeria. A research question and a null hypothesis guided the study. Descriptive survey design was adopted for the study. The population for the study was 14,347 staff in the federal and state universities in North Central Nigeria. A sample of 1,435 was drawn through stratified proportionate sampling technique. Data were collected using questionnaire and interviews. Mean scores and standard deviations were used to answer the research question, whereas t-test statistics were used to test the hypothesis at 0.05 level of significance. The findings of the results showed, among others, that the impact of the quota system and catchment area policies on students’ admission was to a high extent.

  8. Gains from quota trade

    DEFF Research Database (Denmark)

    Andersen, Jesper Levring; Bogetoft, Peter

    2007-01-01

    We provide a framework for evaluating potential effects of introducing tradable quotas to a sector. The effects depend on the economies of scale and scope of the production technology, and on firms' ability and willingness to learn best practice methods (catching up) and to change their input...... and output composition (mix). To illustrate our approach, data from the Danish fishery are used to calculate the potential gains from introducing individually transferable fishing quotas. Data envelopment analysis is used to model the production technology. We find that pure reallocation is as important...

  9. Quotas, Relocation and Jobs

    Science.gov (United States)

    Blumrosen, Alfred

    1975-01-01

    This testimony, before a public hearing of the New York City Commission on Human Rights in May 1974, has two express focuses: one is the question of quotas, and the other is the problem of relocation of plants and facilities in the suburban areas and the consequent difficulties minorities face in retaining equal employment opportunities.…

  10. Sampling high-altitude and stratified mating flights of red imported fire ant.

    Science.gov (United States)

    Fritz, Gary N; Fritz, Ann H; Vander Meer, Robert K

    2011-05-01

    With the exception of an airplane equipped with nets, no method has been developed that successfully samples red imported fire ant, Solenopsis invicta Buren, sexuals in mating/dispersal flights throughout their potential altitudinal trajectories. We developed and tested a method for sampling queens and males during mating flights at altitudinal intervals reaching as high as "140 m. Our trapping system uses an electric winch and a 1.2-m spindle bolted to a swiveling platform. The winch dispenses up to 183 m of Kevlar-core, nylon rope and the spindle stores 10 panels (0.9 by 4.6 m each) of nylon tulle impregnated with Tangle-Trap. The panels can be attached to the rope at various intervals and hoisted into the air by using a 3-m-diameter, helium-filled balloon. Raising or lowering all 10 panels takes approximately 15-20 min. This trap also should be useful for altitudinal sampling of other insects of medical importance.

  11. Improving Precision and Reducing Runtime of Microscopic Traffic Simulators through Stratified Sampling

    Directory of Open Access Journals (Sweden)

    Khewal Bhupendra Kesur

    2013-01-01

    Full Text Available This paper examines the application of Latin Hypercube Sampling (LHS and Antithetic Variables (AVs to reduce the variance of estimated performance measures from microscopic traffic simulators. LHS and AV allow for a more representative coverage of input probability distributions through stratification, reducing the standard error of simulation outputs. Two methods of implementation are examined, one where stratification is applied to headways and routing decisions of individual vehicles and another where vehicle counts and entry times are more evenly sampled. The proposed methods have wider applicability in general queuing systems. LHS is found to outperform AV, and reductions of up to 71% in the standard error of estimates of traffic network performance relative to independent sampling are obtained. LHS allows for a reduction in the execution time of computationally expensive microscopic traffic simulators as fewer simulations are required to achieve a fixed level of precision with reductions of up to 84% in computing time noted on the test cases considered. The benefits of LHS are amplified for more congested networks and as the required level of precision increases.

  12. A direct observation method for auditing large urban centers using stratified sampling, mobile GIS technology and virtual environments.

    Science.gov (United States)

    Lafontaine, Sean J V; Sawada, M; Kristjansson, Elizabeth

    2017-02-16

    With the expansion and growth of research on neighbourhood characteristics, there is an increased need for direct observational field audits. Herein, we introduce a novel direct observational audit method and systematic social observation instrument (SSOI) for efficiently assessing neighbourhood aesthetics over large urban areas. Our audit method uses spatial random sampling stratified by residential zoning and incorporates both mobile geographic information systems technology and virtual environments. The reliability of our method was tested in two ways: first, in 15 Ottawa neighbourhoods, we compared results at audited locations over two subsequent years, and second; we audited every residential block (167 blocks) in one neighbourhood and compared the distribution of SSOI aesthetics index scores with results from the randomly audited locations. Finally, we present interrater reliability and consistency results on all observed items. The observed neighbourhood average aesthetics index score estimated from four or five stratified random audit locations is sufficient to characterize the average neighbourhood aesthetics. The SSOI was internally consistent and demonstrated good to excellent interrater reliability. At the neighbourhood level, aesthetics is positively related to SES and physical activity and negatively correlated with BMI. The proposed approach to direct neighbourhood auditing performs sufficiently and has the advantage of financial and temporal efficiency when auditing a large city.

  13. Application of a stratified random sampling technique to the estimation and minimization of respirable quartz exposure to underground miners

    International Nuclear Information System (INIS)

    Makepeace, C.E.; Horvath, F.J.; Stocker, H.

    1981-11-01

    The aim of a stratified random sampling plan is to provide the best estimate (in the absence of full-shift personal gravimetric sampling) of personal exposure to respirable quartz among underground miners. One also gains information of the exposure distribution of all the miners at the same time. Three variables (or strata) are considered in the present scheme: locations, occupations and times of sampling. Random sampling within each stratum ensures that each location, occupation and time of sampling has equal opportunity of being selected without bias. Following implementation of the plan and analysis of collected data, one can determine the individual exposures and the mean. This information can then be used to identify those groups whose exposure contributes significantly to the collective exposure. In turn, this identification, along with other considerations, allows the mine operator to carry out a cost-benefit optimization and eventual implementation of engineering controls for these groups. This optimization and engineering control procedure, together with the random sampling plan, can then be used in an iterative manner to minimize the mean value of the distribution and collective exposures

  14. Stratifying empiric risk of schizophrenia among first degree relatives using multiple predictors in two independent Indian samples.

    Science.gov (United States)

    Bhatia, Triptish; Gettig, Elizabeth A; Gottesman, Irving I; Berliner, Jonathan; Mishra, N N; Nimgaonkar, Vishwajit L; Deshpande, Smita N

    2016-12-01

    Schizophrenia (SZ) has an estimated heritability of 64-88%, with the higher values based on twin studies. Conventionally, family history of psychosis is the best individual-level predictor of risk, but reliable risk estimates are unavailable for Indian populations. Genetic, environmental, and epigenetic factors are equally important and should be considered when predicting risk in 'at risk' individuals. To estimate risk based on an Indian schizophrenia participant's family history combined with selected demographic factors. To incorporate variables in addition to family history, and to stratify risk, we constructed a regression equation that included demographic variables in addition to family history. The equation was tested in two independent Indian samples: (i) an initial sample of SZ participants (N=128) with one sibling or offspring; (ii) a second, independent sample consisting of multiply affected families (N=138 families, with two or more sibs/offspring affected with SZ). The overall estimated risk was 4.31±0.27 (mean±standard deviation). There were 19 (14.8%) individuals in the high risk group, 75 (58.6%) in the moderate risk and 34 (26.6%) in the above average risk (in Sample A). In the validation sample, risks were distributed as: high (45%), moderate (38%) and above average (17%). Consistent risk estimates were obtained from both samples using the regression equation. Familial risk can be combined with demographic factors to estimate risk for SZ in India. If replicated, the proposed stratification of risk may be easier and more realistic for family members. Copyright © 2016. Published by Elsevier B.V.

  15. Development and enrolee satisfaction with basic medical insurance in China: A systematic review and stratified cluster sampling survey.

    Science.gov (United States)

    Jing, Limei; Chen, Ru; Jing, Lisa; Qiao, Yun; Lou, Jiquan; Xu, Jing; Wang, Junwei; Chen, Wen; Sun, Xiaoming

    2017-07-01

    Basic Medical Insurance (BMI) has changed remarkably over time in China because of health reforms that aim to achieve universal coverage and better health care with adequate efforts by increasing subsidies, reimbursement, and benefits. In this paper, we present the development of BMI, including financing and operation, with a systematic review. Meanwhile, Pudong New Area in Shanghai was chosen as a typical BMI sample for its coverage and management; a stratified cluster sampling survey together with an ordinary logistic regression model was used for the analysis. Enrolee satisfaction and the factors associated with enrolee satisfaction with BMI were analysed. We found that the reenrolling rate superficially improved the BMI coverage and nearly achieved universal coverage. However, BMI funds still faced dual contradictions of fund deficit and insured under compensation, and a long-term strategy is needed to realize the integration of BMI schemes with more homogeneous coverage and benefits. Moreover, Urban Resident Basic Medical Insurance participants reported a higher rate of dissatisfaction than other participants. The key predictors of the enrolees' satisfaction were awareness of the premium and compensation, affordability of out-of-pocket costs, and the proportion of reimbursement. These results highlight the importance that the Chinese government takes measures, such as strengthening BMI fund management, exploring mixed payment methods, and regulating sequential medical orders, to develop an integrated medical insurance system of universal coverage and vertical equity while simultaneously improving enrolee satisfaction. Copyright © 2017 John Wiley & Sons, Ltd.

  16. PREDOMINANTLY LOW METALLICITIES MEASURED IN A STRATIFIED SAMPLE OF LYMAN LIMIT SYSTEMS AT Z  = 3.7

    Energy Technology Data Exchange (ETDEWEB)

    Glidden, Ana; Cooper, Thomas J.; Simcoe, Robert A. [Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139 (United States); Cooksey, Kathy L. [Department of Physics and Astronomy, University of Hawai‘i at Hilo, 200 West Kāwili Street, Hilo, HI 96720 (United States); O’Meara, John M., E-mail: aglidden@mit.edu, E-mail: tjcooper@mit.edu, E-mail: simcoe@space.mit.edu, E-mail: kcooksey@hawaii.edu, E-mail: jomeara@smcvt.edu [Department of Physics, Saint Michael’s College, One Winooski Park, Colchester, VT 05439 (United States)

    2016-12-20

    We measured metallicities for 33 z = 3.4–4.2 absorption line systems drawn from a sample of H i-selected-Lyman limit systems (LLSs) identified in Sloan Digital Sky Survey (SDSS) quasar spectra and stratified based on metal line features. We obtained higher-resolution spectra with the Keck Echellette Spectrograph and Imager, selecting targets according to our stratification scheme in an effort to fully sample the LLS population metallicity distribution. We established a plausible range of H i column densities and measured column densities (or limits) for ions of carbon, silicon, and aluminum, finding ionization-corrected metallicities or upper limits. Interestingly, our ionization models were better constrained with enhanced α -to-aluminum abundances, with a median abundance ratio of [ α /Al] = 0.3. Measured metallicities were generally low, ranging from [M/H] = −3 to −1.68, with even lower metallicities likely for some systems with upper limits. Using survival statistics to incorporate limits, we constructed the cumulative distribution function (CDF) for LLS metallicities. Recent models of galaxy evolution propose that galaxies replenish their gas from the low-metallicity intergalactic medium (IGM) via high-density H i “flows” and eject enriched interstellar gas via outflows. Thus, there has been some expectation that LLSs at the peak of cosmic star formation ( z  ≈ 3) might have a bimodal metallicity distribution. We modeled our CDF as a mix of two Gaussian distributions, one reflecting the metallicity of the IGM and the other representative of the interstellar medium of star-forming galaxies. This bimodal distribution yielded a poor fit. A single Gaussian distribution better represented the sample with a low mean metallicity of [M/H] ≈ −2.5.

  17. Executive control resources and frequency of fatty food consumption: findings from an age-stratified community sample.

    Science.gov (United States)

    Hall, Peter A

    2012-03-01

    Fatty foods are regarded as highly appetitive, and self-control is often required to resist consumption. Executive control resources (ECRs) are potentially facilitative of self-control efforts, and therefore could predict success in the domain of dietary self-restraint. It is not currently known whether stronger ECRs facilitate resistance to fatty food consumption, and moreover, it is unknown whether such an effect would be stronger in some age groups than others. The purpose of the present study was to examine the association between ECRs and consumption of fatty foods among healthy community-dwelling adults across the adult life span. An age-stratified sample of individuals between 18 and 89 years of age attended two laboratory sessions. During the first session they completed two computer-administered tests of ECRs (Stroop and Go-NoGo) and a test of general cognitive function (Wechsler Abbreviated Scale of Intelligence); participants completed two consecutive 1-week recall measures to assess frequency of fatty and nonfatty food consumption. Regression analyses revealed that stronger ECRs were associated with lower frequency of fatty food consumption over the 2-week interval. This association was observed for both measures of ECR and a composite measure. The effect remained significant after adjustment for demographic variables (age, gender, socioeconomic status), general cognitive function, and body mass index. The observed effect of ECRs on fatty food consumption frequency was invariant across age group, and did not generalize to nonfatty food consumption. ECRs may be potentially important, though understudied, determinants of dietary behavior in adults across the life span.

  18. Prevalence and Risk Factors of Dengue Infection in Khanh Hoa Province, Viet Nam: A Stratified Cluster Sampling Survey.

    Science.gov (United States)

    Mai, Vien Quang; Mai, Trịnh Thị Xuan; Tam, Ngo Le Minh; Nghia, Le Trung; Komada, Kenichi; Murakami, Hitoshi

    2018-05-19

    Dengue is a clinically important arthropod-borne viral disease with increasing global incidence. Here we aimed to estimate the prevalence of dengue infections in Khanh Hoa Province, central Viet Nam, and to identify risk factors for infection. We performed a stratified cluster sampling survey including residents of 3-60 years of age in Nha Trang City, Ninh Hoa District and Dien Khanh District, Khanh Hoa Province, in October 2011. Immunoglobulin G (IgG) and immunoglobulin M (IgM) against dengue were analyzed using a rapid test kit. Participants completed a questionnaire exploring clinical dengue incidence, socio-economic status, and individual behavior. A household checklist was used to examine environment, mosquito larvae presence, and exposure to public health interventions. IgG positivity was 20.5% (urban, 16.3%; rural, 23.0%), IgM positivity was 6.7% (urban, 6.4%; rural, 6.9%), and incidence of clinically compatible dengue during the prior 3 months was 2.8 per 1,000 persons (urban, 1.7; rural, 3.4). For IgG positivity, the adjusted odds ratio (AOR) was 2.68 (95% confidence interval [CI], 1.24-5.81) for mosquito larvae presence in water pooled in old tires and was 3.09 (95% CI, 1.75-5.46) for proximity to a densely inhabited area. For IgM positivity, the AOR was 3.06 (95% CI, 1.50-6.23) for proximity to a densely inhabited area. Our results indicated rural penetration of dengue infections. Control measures should target densely inhabited areas, and may include clean-up of discarded tires and water-collecting waste.

  19. Evaluating effectiveness of down-sampling for stratified designs and unbalanced prevalence in Random Forest models of tree species distributions in Nevada

    Science.gov (United States)

    Elizabeth A. Freeman; Gretchen G. Moisen; Tracy S. Frescino

    2012-01-01

    Random Forests is frequently used to model species distributions over large geographic areas. Complications arise when data used to train the models have been collected in stratified designs that involve different sampling intensity per stratum. The modeling process is further complicated if some of the target species are relatively rare on the landscape leading to an...

  20. Energy consumption quota of public buildings based on statistical analysis

    International Nuclear Information System (INIS)

    Zhao Jing; Xin Yajuan; Tong Dingding

    2012-01-01

    The establishment of building energy consumption quota as a comprehensive indicator used to evaluate the actual energy consumption level is an important measure for promoting the development of building energy efficiency. This paper focused on the determination method of the quota, and firstly introduced the procedure of establishing energy consumption quota of public buildings including four important parts: collecting data, classifying and calculating EUIs, standardizing EUIs, determining the measure method of central tendency. The paper also illustrated the standardization process of EUI by actual calculation based on the samples of 10 commercial buildings and 19 hotel buildings. According to the analysis of the frequency distribution of standardized EUIs of sample buildings and combining the characteristics of each measure method of central tendency, comprehensive application of mode and percentage rank is selected to be the best method for determining the energy consumption quota of public buildings. Finally the paper gave some policy proposals on energy consumption quota to help achieve the goal of further energy conservation. - Highlights: ► We introduce the procedure of determining energy consumption quota (ECQ). ► We illustrate the standardization process of EUI by actual calculation of samples. ► Measures of central tendency are brought into determine the ECQ. ► Comprehensive application of mode and percentage rank is the best method for ECQ. ► Punitive or incentive measures for ECQ are proposed.

  1. Stratified random sampling plans designed to assist in the determination of radon and radon daughter concentrations in underground uranium mine atmosphere

    International Nuclear Information System (INIS)

    Makepeace, C.E.

    1981-01-01

    Sampling strategies for the monitoring of deleterious agents present in uranium mine air in underground and surface mining areas are described. These methods are designed to prevent overexposure of the lining of the respiratory system of uranium miners to ionizing radiation from radon and radon daughters, and whole body overexposure to external gamma radiation. A detailed description is provided of stratified random sampling monitoring methodology for obtaining baseline data to be used as a reference for subsequent compliance assessment

  2. Quota enforcement in resource industries

    DEFF Research Database (Denmark)

    Hansen, Lars Gårn; Jensen, Frank; Nøstbakken, Linda

    cant non-compliance and exogenous constraints on nes and enforcement budget. We propose a new enforcement system based on self-reporting of excess extraction and explicit di erentiation of inspection rates based on compliance history. In particular, we use state-dependent enforcement to induce rms...... to self-report excess extraction. We show that such system increases the e ectiveness of quota management by allowing the regulator to implement a wider range of aggregate extraction targets than under traditional enforcement, while ensuring an ecient allocation of aggregate extraction. In addition......Quotas or permits are frequently used in the management of renewable resources and emissions. However, in many industries there is concern about the basic e ectiveness of quotas due to non-compliance. We develop an enforcement model of a quota-regulated resource and focus on a situation with signi...

  3. Energy consumption quota management of Wanda commercial buildings in China

    Science.gov (United States)

    Sun, D. B.; Xiao, H.; Wang, X.; Liu, J. J.; Wang, X.; Jin, X. Q.; Wang, J.; Xie, X. K.

    2016-08-01

    There is limited research of commercial buildings’ energy use data conducted based on practical analysis in China nowadays. Some energy consumption quota tools like Energy Star in U.S or VDI 3807 in Germany have limitation in China's building sector. This study introduces an innovative methodology of applying energy use quota model and empirical management to commercial buildings, which was in accordance of more than one hundred opened shopping centers of a real estate group in China. On the basis of statistical benchmarking, a new concept of “Modified coefficient”, which considers weather, occupancy, business layout, operation schedule and HVAC efficiency, is originally introduced in this paper. Our study shows that the average energy use quota increases from north to south. The average energy use quota of sample buildings is 159 kWh/(m2.a) of severe cold climate zone, 179 kWh/(m2.a) of cold zone, 188 kWh/(m2.a) of hot summer and cold winter zone, and 200 kWh/(m2.a) of hot summer and warm winter zone. The energy use quota model has been validated in the property management for year 2016, providing a new method of commercial building energy management to the industry. As a key result, there is 180 million energy saving potential based on energy quota management in 2016, equals to 6.2% saving rate of actual energy use in 2015.

  4. Quota enforcement in resource industries

    DEFF Research Database (Denmark)

    Hansen, Lars Gårn; Jensen, Frank; Nøstbakken, Linda

    2014-01-01

    -compliance and exogenous constraints on fines and enforcement budget. We propose a new enforcement system based on self-reporting of excess extraction and explicit differentiation of inspection rates depending on compliance history. We use differentiated inspections to induce firms to self-report excess extraction....... This system increases the effectiveness of the quota by allowing the regulator to implement a wider range of aggregate extraction targets than under traditional enforcement, while ensuring an efficient allocation of extraction. In addition, inspection costs can be reduced without reductions in welfare.......Quotas are frequently used in the management of renewable resources and emissions. However, in many industries there is concern about their basic effectiveness due to non-compliance. We develop an enforcement model of a quota-regulated resource and focus on a situation with significant non...

  5. Temporal Justice, Youth Quotas and Libertarianism

    NARCIS (Netherlands)

    Wissenburg, M.L.J.

    2015-01-01

    Quotas, including youth quotas for representative institutions, are usually evaluated from within the social justice discourse. That discourse relies on several questionable assumptions, seven of which I critically address and radically revise in this contribution from a libertarian perspective.

  6. 7 CFR 1463.105 - Base quota levels for eligible quota holders.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Base quota levels for eligible quota holders. 1463.105 Section 1463.105 Agriculture Regulations of the Department of Agriculture (Continued) COMMODITY... TRANSITION PROGRAM Tobacco Transition Payment Program § 1463.105 Base quota levels for eligible quota holders...

  7. 27 CFR 6.71 - Quota sales.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Quota sales. 6.71 Section 6.71 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS âTIED-HOUSEâ Unlawful Inducements Quota Sales § 6.71 Quota sales. The act by an...

  8. Gender quotas in development programming

    NARCIS (Netherlands)

    Windt, van der Peter; Humphreys, Macartan; Sanchez de la Sierra, Raul

    2018-01-01

    We examine whether gender quotas introduced by development agencies empower women. As part of a development program, an international organization created community management committees in 661 villages to oversee village level program expenditures. In a randomly selected half of these villages the

  9. Monitoring and identification of spatiotemporal landscape changes in multiple remote sensing images by using a stratified conditional Latin hypercube sampling approach and geostatistical simulation.

    Science.gov (United States)

    Lin, Yu-Pin; Chu, Hone-Jay; Huang, Yu-Long; Tang, Chia-Hsi; Rouhani, Shahrokh

    2011-06-01

    This study develops a stratified conditional Latin hypercube sampling (scLHS) approach for multiple, remotely sensed, normalized difference vegetation index (NDVI) images. The objective is to sample, monitor, and delineate spatiotemporal landscape changes, including spatial heterogeneity and variability, in a given area. The scLHS approach, which is based on the variance quadtree technique (VQT) and the conditional Latin hypercube sampling (cLHS) method, selects samples in order to delineate landscape changes from multiple NDVI images. The images are then mapped for calibration and validation by using sequential Gaussian simulation (SGS) with the scLHS selected samples. Spatial statistical results indicate that in terms of their statistical distribution, spatial distribution, and spatial variation, the statistics and variograms of the scLHS samples resemble those of multiple NDVI images more closely than those of cLHS and VQT samples. Moreover, the accuracy of simulated NDVI images based on SGS with scLHS samples is significantly better than that of simulated NDVI images based on SGS with cLHS samples and VQT samples, respectively. However, the proposed approach efficiently monitors the spatial characteristics of landscape changes, including the statistics, spatial variability, and heterogeneity of NDVI images. In addition, SGS with the scLHS samples effectively reproduces spatial patterns and landscape changes in multiple NDVI images.

  10. The relationships between sixteen perfluorinated compound concentrations in blood serum and food, and other parameters, in the general population of South Korea with proportionate stratified sampling method.

    Science.gov (United States)

    Kim, Hee-Young; Kim, Seung-Kyu; Kang, Dong-Mug; Hwang, Yong-Sik; Oh, Jeong-Eun

    2014-02-01

    Serum samples were collected from volunteers of various ages and both genders using a proportionate stratified sampling method, to assess the exposure of the general population in Busan, South Korea to perfluorinated compounds (PFCs). 16 PFCs were investigated in serum samples from 306 adults (124 males and 182 females) and one day composite diet samples (breakfast, lunch, and dinner) from 20 of the serum donors, to investigate the relationship between food and serum PFC concentrations. Perfluorooctanoic acid and perfluorooctanesulfonic acid were the dominant PFCs in the serum samples, with mean concentrations of 8.4 and 13 ng/mL, respectively. Perfluorotridecanoic acid was the dominant PFC in the composite food samples, ranging from studies. We confirmed from the relationships between questionnaire results and the PFC concentrations in the serum samples, that food is one of the important contribution factors of human exposure to PFCs. However, there were no correlations between the PFC concentrations in the one day composite diet samples and the serum samples, because a one day composite diet sample is not necessarily representative of a person's long-term diet and because of the small number of samples taken. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Free emission quotas in the climate policy - consequences of different ways of granting quotas

    International Nuclear Information System (INIS)

    Hagem, Cathrine

    2001-01-01

    The article discusses how different types of conditions and rules of granting quotas over time affects the companies' decision about production and implementation of measures to reduce emission. The first section analyses a quota system in which the granting of free emission quotas are based on the firm's emission history. The effects of tradable free quotas are compared to the effects of non-tradable free quotas. The second part analyses a quota system based on the firms' needs for a free system in order to secure continued production

  12. Free emission quotas in the environmental policy

    International Nuclear Information System (INIS)

    Maestad, Ottar

    2001-01-01

    The granting of free emission quotas to selected companies or sectors is currently hotly debated in the climate policy. This article deals with whether such quotas can be used and, if so, how they should be used in order to achieve a more cost-effective environmental policy. It asks on what basis it may be appropriate to grant free emission quotas and discusses what criteria should be used, and if there are better alternatives. It is concluded that free emission quotas are a cost-effective instrument to avoid firm closures and reductions for sufficiently purposeful criteria. Quotas are at best only second best in reducing emigration of firms or production to other countries. However, since more efficient means may be difficult to implement, free emission quotas may be useful in these cases as well

  13. Quota Prices - Analysis and Reporting on Pacific Groundfish IFQ Quota Market

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The transfer of quota pounds and quota shares between participants in the Pacific Groundfish IFQ plays a critical role in facilitating fuller and more efficient...

  14. Gender Quotas for Corporate Boards

    OpenAIRE

    Elomäki, Anna

    2017-01-01

    Gender quotas for corporate boards can be seen as a way of drawing attention to gendered power within the economy as well as a way to democratize the economy, yet the debate about them has focused on the economic and business benefits of gender equality rather than on gender justice or democracy. This article examines how women’s under-representation in economic decision-making was constituted as an economic problem in the European Union’s gender-equality policies and how the economization of...

  15. Stratified Entomological Sampling in Preparation for an Area-Wide Integrated Pest Management Program: The Example of Glossina palpalis gambiensis (Diptera: Glossinidae) in the Niayes of Senegal

    International Nuclear Information System (INIS)

    Bouyer, Jeremy; Seck, Momar Talla; Guerrini, Laure; Sall, Baba; Ndiaye, Elhadji Youssou; Vreysen, Marc J.B.

    2010-01-01

    The riverine tsetse species Glossina palpalis gambiensis Vanderplank 1949 (Diptera: Glossinidae) inhabits riparian forests along river systems in West Africa. The government of Senegal has embarked on a project to eliminate this tsetse species, and African animal trypanosomoses, from the Niayes are using an area-wide integrated pest management approach. A stratified entomological sampling strategy was therefore developed using spatial analytical tools and mathematical modeling. A preliminary phytosociological census identified eight types of suitable habitat, which could be discriminated from LandSat 7ETM satellite images and denominated wet areas. At the end of March 2009, 683 unbaited Vavoua traps had been deployed, and the observed infested area in the Niayes was 525 km2. In the remaining area, a mathematical model was used to assess the risk that flies were present despite a sequence of zero catches. The analysis showed that this risk was above 0.05 in19% of this area that will be considered as infested during the control operations.The remote sensing analysis that identifed the wet areas allowed a restriction of the area to be surveyed to 4% of the total surface area (7,150km2), whereas the mathematical model provided an efficient method to improve the accuracy and the robustness of the sampling protocol. The final size of the control area will be decided based on the entomological collection data.This entomological sampling procedure might be used for other vector or pest control scenarios. (Authors)

  16. Quotas for the select few

    International Nuclear Information System (INIS)

    Marcan, P.

    2007-01-01

    Carbon dioxide quotas are no longer a topic only for politicians or Nobel prize winners or a subject of ambitious EU energetic strategies. For the third year they have also been a factor European companies have to take into account when calculating their plans for the forthcoming period. It is a fact that during the first trading period of the emission trading scheme that ends this year, the emission permits represented a big profit making opportunity for Slovak companies. Or compliance with the new rules at least did not cost them anything. But this pleasant position may change in the upcoming 5-year period starting in January. The new emission quota for the 2008 - 2012 period which Brussels has approved for Slovakia will have an impact on individual companies. And so many companies that had a reserve hidden in the original requirement will have to calculate with a certain limitation as far as their free space for ecological manoeuvres is concerned. However, there is still a group of select companies that will get more: power generating companies controlled by the state. (authors)

  17. Design of dry sand soil stratified sampler

    Science.gov (United States)

    Li, Erkang; Chen, Wei; Feng, Xiao; Liao, Hongbo; Liang, Xiaodong

    2018-04-01

    This paper presents a design of a stratified sampler for dry sand soil, which can be used for stratified sampling of loose sand under certain conditions. Our group designed the mechanical structure of a portable, single - person, dry sandy soil stratified sampler. We have set up a mathematical model for the sampler. It lays the foundation for further development of design research.

  18. 21 CFR 1303.13 - Adjustments of aggregate production quotas.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Adjustments of aggregate production quotas. 1303.13 Section 1303.13 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE QUOTAS Aggregate Production and Procurement Quotas § 1303.13 Adjustments of aggregate production quotas. (a) The...

  19. 21 CFR 1303.11 - Aggregate production quotas.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Aggregate production quotas. 1303.11 Section 1303.11 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE QUOTAS Aggregate Production and Procurement Quotas § 1303.11 Aggregate production quotas. (a) The Administrator shall determine...

  20. Sharing a quota on cumulative carbon emissions

    International Nuclear Information System (INIS)

    Raupach, Michael R.; Davis, Steven J.; Peters, Glen P.; Andrew, Robbie M.; Canadell, Josep G.; Ciais, Philippe

    2014-01-01

    Any limit on future global warming is associated with a quota on cumulative global CO 2 emissions. We translate this global carbon quota to regional and national scales, on a spectrum of sharing principles that extends from continuation of the present distribution of emissions to an equal per-capita distribution of cumulative emissions. A blend of these endpoints emerges as the most viable option. For a carbon quota consistent with a 2 C warming limit (relative to pre-industrial levels), the necessary long-term mitigation rates are very challenging (typically over 5% per year), both because of strong limits on future emissions from the global carbon quota and also the likely short-term persistence in emissions growth in many regions. (authors)

  1. Holland bought Slovakian's emission quotas

    International Nuclear Information System (INIS)

    TREND

    2003-01-01

    It is not a direct trade but more an environmental investment. Dutch government decided to buy over 5 million tons of carbon dioxide emission quotas of Rumania, Hungary and Slovakia. But this is not a direct purchase; it is related to investments into major projects that would decrease emission of greenhouse gases in the mentioned countries. Holland will improve its emission balance set by Kyoto Protocol and 'on the other hand we will offer eastern European countries technologies they are missing,' explained the main objectives of Dutch environmental projects Erik Saat from Senter agency at Dutch Ministry of Economy. The Dutch agency has so far selected one project in Slovakia - absorption of methane gas on waste dumps of eight Slovak towns. This project in value of 5 million Euro will decrease the emission by an equivalent of 500 thousand tons of CO 2 . Slovak Ministry of Environment that has to approve these projects welcomes any activity that would lead to decreasing greenhouse gas pollution. Every three months Senter agency select the best projects submitted in order to fulfil the commitments resulting from Kyoto Protocol. (Author)

  2. ETS: free quotas for subsidy coal

    International Nuclear Information System (INIS)

    Mary, Olivier

    2016-01-01

    This article comments information published by a NGO according to which less than 10 per cent of investments financed through the 10c article of the ETS European directive have been made on technologies which emit less greenhouse gases, or on a diversification of the energy mix, and 90 pc of these quotas have been used in East European countries to modernize obsolete thermal plants, mainly coal plants, or to build new ones. These facts also highlight a flagrant lack of transparency in the award and use of these quotas

  3. AKRO/SF: Community Development Quota (CDQ) System

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Western Alaska Community Development Quota (CDQ) Program allocates a percentage of all Bering Sea and Aleutian Islands quotas for groundfish, prohibited species,...

  4. 21 CFR 1303.21 - Individual manufacturing quotas.

    Science.gov (United States)

    2010-04-01

    ... controlled substance listed in Schedule I or II, and who applies for a manufacturing quota, an individual... basic class. Any manufacturing quota fixed and issued by the Administrator shall be subject to his... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Individual manufacturing quotas. 1303.21 Section...

  5. Quotas and Decentralization (Indonesia) | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    International Development Research Centre Government of Canada ... Although there has been general compliance with the quota for women candidates, ... party policies and mechanisms that tend to create or break down barriers to women. ... Call for new OWSD Fellowships for Early Career Women Scientists now open.

  6. 50 CFR 635.27 - Quotas.

    Science.gov (United States)

    2010-10-01

    ... landings, the period of time remaining in the current fishing year, current and historical landings trends... the convenience of the user, the revised text is set forth as follows: § 635.27 Quotas. (d) Atlantic..., current and historical landings trends, and any other relevant factors, NMFS will file for publication...

  7. Gender Quotas on Board of Directors

    DEFF Research Database (Denmark)

    Smith, Nina

    2013-01-01

    Beside arguments of fairness and equal opportunities, it is often argued that gender diversity on boards of directors may improve firm performance, but the empirical results are mixed and often negative. Based on the available research, gender quotas on boards of directors cannot be justified...

  8. An Adjustment Restriction on Fish Quota

    NARCIS (Netherlands)

    Dijk, van Diana; Hendrix, E.M.T.; Haijema, Rene; Groeneveld, R.A.; Ierland, van E.C.

    2017-01-01

    Management objectives of the European Union for North Sea fish stocks are shifting towards considering both biological sustainability and economic benefits. As part of multiannual management plans, an adjustment restriction on fish quota has been introduced. Its objective is to obtain an

  9. 21 CFR 1303.12 - Procurement quotas.

    Science.gov (United States)

    2010-04-01

    ... and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE QUOTAS Aggregate Production and... substance, and, if a controlled substance listed in any schedule, the schedule number and Administration... Administration. See the Table of DEA Mailing Addresses in § 1321.01 of this chapter for the current mailing...

  10. 50 CFR 622.42 - Quotas.

    Science.gov (United States)

    2010-10-01

    ... million kg). The Gulf migratory group is divided into eastern and western zones separated by 87°31′06″ W. long., which is a line directly south from the Alabama/Florida boundary. Quotas for the eastern and western zones are as follows: (A) Eastern zone—2.25 million lb (1.02 million kg), which is further divided...

  11. OPEC ducks quota issue amid glut worries

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    This paper reports that the Organization of Petroleum Exporting Countries has ducked the question of reestablishing quotas despite the looming prospect of a second quarter oil price slide. OPEC ministers meeting in Vienna late last month approved continuing free-for-all production in the first quarter and ordered the ministerial monitoring committee to tackle the question of second quarter production levels when it meets in Geneva Feb. 12. Oil markets responded to the lack of action by dropping futures prices

  12. A comparison of biogenic iron quotas during a diatom spring bloom using multiple approaches

    Directory of Open Access Journals (Sweden)

    A. L. King

    2012-02-01

    Full Text Available Biogenic Fe quotas were determined using three distinct techniques on samples collected concurrently in the subtropical Pacific Ocean east of New Zealand. Fe quotas were measured using radioisotope uptake experiments (24 h incubation, bulk filtration and analysis by inductively-coupled plasma mass spectrometer (ICPMS, and single-cell synchrotron x-ray fluorescence (SXRF analysis over a sixteen-day period (year days 263 to 278 of 2008 during a quasi-Lagrangian drifter experiment that tracked the evolution of the annual spring diatom bloom within a counter-clockwise open-ocean eddy. Overall, radioisotope uptake-determined Fe quotas (washed with oxalate reagent to remove extracellular Fe were the lowest (0.5–1.0 mmol Fe:mol P; 4–8 μmol Fe:mol C, followed by single-cell Fe quotas (2.3–7.5 mmol Fe:mol P; 17–57 μmol Fe:mol C, and the highest and most variable quotas were from the bulk filtration ICPMS approach that used the oxalate reagent wash, corrected for lithogenic Fe using Al (0.8–21 mmol Fe:mol P; 4–136 μmol Fe:mol C. During the evolution of the spring bloom within the eddy (year days 263 to 272, the surface mixed layer inventories of particulate biogenic elements (C, N, P, Si and chlorophyll increased while Fe quotas estimated from all three approaches exhibited a general decline. After the onset of the bloom decline, the drogued buoys exited the eddy center (days 273 to 277. Fe quotas returned to pre-bloom values during this part of the study. Our standardized and coordinated sampling protocols reveal the general observed trend in Fe quotas: ICPMS > SXRF > radioisotope uptake. We discuss the inherent differences between the techniques and argue that each technique has its individual merits and uniquely contributes to the characterization of the oceanic particulate Fe pool.

  13. Practical guidebook about the market of CO2 emission quotas

    International Nuclear Information System (INIS)

    2005-01-01

    Since January 1, 2005, the European directive about the trading of CO 2 emission quotas foresees the allocation of CO 2 emission quotas to the industrial sectors that generate huge amounts of greenhouse gases (energy generation, cement, glass, steel-making, mineral and paper industries). A system of trading of CO 2 quotas has been implemented and allows the companies to exchange, sale or purchase quotas in order to be conformable with the volume of CO 2 they have been authorized to release in the atmosphere. This guidebook is a vade mecum of the management of emission quotas. It explains the actions of the international community in favor of the fight against greenhouse emissions, the 3 flexibility mechanisms, the French environmental policy, the European system of fight against climatic change, the CO 2 quotas system and its practical implementation. (J.S.)

  14. Norway and the EU may trade emission quotas from 2005

    International Nuclear Information System (INIS)

    Tjernshaugen, Andreas

    2002-01-01

    The EU commission wants to implement quota trade with climate gases from 2005. The proposal, which came in October 2001, describes a quota system limited to the emission of CO 2 in certain industrial sectors. Sources like road traffic and heating of buildings are not comprised by the proposal. It is intended that the agreement will later include more climate gases and more types of activities. This expansion of the implementation becomes most important from 2008-2012, for then the Kyoto Protocol sets the limits for six types of climate gases and lays down rules for international trade with emission quotas. Norway is likely to go in for a limited quota system for 2005 to 2007 and apply for an agreement with the quota market of the EU. It is not certain, however, that the Norwegian authorities will limit the national quota system the same way

  15. National plan project of quotas allocation. Reference period

    International Nuclear Information System (INIS)

    2004-06-01

    This document described the national plan project of greenhouse gases quotas allocation, in application of the directive 2003/87/CE. It is a preliminary document providing hypothesis, data and results which could well be modified. It presents in seven chapters the determination of the final quotas quantity, the determination of the final quotas quantity per each activity sectors and per installation, the technical aspects, the community policy and legislation, the public consultation and other criteria analysis. (A.L.B.)

  16. National plan of quotas assignment. 2005-2007 reference period

    International Nuclear Information System (INIS)

    2004-07-01

    This document described the national plan of greenhouse gases quotas allocation, in application of the directive 2003/87/CE. Data and results presented could well be modified in particular in function of corrective demands proposed by the owners since the beginning of the public consulting to the notification of the affected quotas quantity. It presents in seven chapters the determination of the final quotas quantity, the determination of the final quotas quantity per each activity sectors and per installation, the technical aspects, the community policy and legislation, the public consultation and other criteria analysis. (A.L.B.)

  17. Investment behaviour in individual nontransferable quota systems

    DEFF Research Database (Denmark)

    Jensen, Frank; Andersen, Jesper Levring; Jensen, Carsten Lynge

    2012-01-01

    This article studies the investment behaviour of the Danish demersal fishery in the North Sea. For the study period, this fishery is regulated by variants of individual nontransferable quotas. It is shown that interest rates and capital stocks are primary determinants of investments. Another......, the variance of the estimated parameters is lower in the disaggregated models. This result arises because vessels in the disaggregated models are more homogeneous. Furthermore, investments in machinery, electronics and vessels are governed by one year lagged variables, while investment in gears is governed...

  18. Policies and practices in the health-related reception of quota refugees in Denmark

    DEFF Research Database (Denmark)

    Frederiksen, Hanne W; Krasnik, Allan; Nørredam, Marie

    2012-01-01

    Quota refugees coming to Denmark are mandated refugee status offshore and approximately 500 quota refugees are resettled annually. Upon arrival to Denmark, quota refugees are received directly in the municipalities and municipal caseworkers therefore have the practical responsibility for their he......Quota refugees coming to Denmark are mandated refugee status offshore and approximately 500 quota refugees are resettled annually. Upon arrival to Denmark, quota refugees are received directly in the municipalities and municipal caseworkers therefore have the practical responsibility...

  19. Optimizing Board Effectiveness with Gender Diversity : Are Quotas the Answer?

    OpenAIRE

    Annemarie Durbin

    2011-01-01

    Women are underrepresented on corporate boards but are quotas the answer? Not according to the author. Annemarie Durbin cites evidence that using quotas to increase female representation can lead to tokenism, diminish the overall value of diversity on boards, affect board dynamics, and potentially lead to diluted commitments from existing female board directors. She recommends that, instea...

  20. Emissions trading with offset markets and free quota allocations

    Energy Technology Data Exchange (ETDEWEB)

    Rosendahl, Knut Einar; Strand, Jon

    2012-07-01

    We study interactions between a 'policy bloc's' emissions quota market and an offset market where emissions offsets can be purchased from a non-policy 'fringe' of countries (such as for the CDM under the Kyoto Protocol). Policy-bloc firms are assumed to benefit from free quota allocations that are updated according to either past emissions or past outputs. We show that both overall abatement, and the allocation of given abatement between the policy bloc and the fringe, tend to be inefficient. When the policy-bloc quota market and offset markets are fully integrated (and firms buy offsets directly from the fringe), and all quotas and offsets must be traded at a single price, it is optimal for the policy bloc to either not constrain the offset market whatsoever, or to ban offsets completely. The former (latter) case occurs when free allocation of quotas is not too generous (very generous), and the offset market can profitably deliver large (only a small) quota amounts. Governments of policy countries would however instead prefer to buy offsets directly from the fringe at a price below the policy-bloc quota price. The offset price will then be below the marginal damage cost of emissions, and the quota price in the policy bloc above marginal damage cost. This solution is also inefficient as the policy bloc (acting as a monopsonist) purchases too few offsets from the fringe.(Author)

  1. Prevalence and Risk Factors of Overweight and Obesity among Children Aged 6–59 Months in Cameroon: A Multistage, Stratified Cluster Sampling Nationwide Survey

    Science.gov (United States)

    Tchoubi, Sébastien; Sobngwi-Tambekou, Joëlle; Noubiap, Jean Jacques N.; Asangbeh, Serra Lem; Nkoum, Benjamin Alexandre; Sobngwi, Eugene

    2015-01-01

    Background Childhood obesity is one of the most serious public health challenges of the 21st century. The prevalence of overweight and obesity among children (overweight and obesity among children aged 6 months to 5 years in Cameroon in 2011. Methods Four thousand five hundred and eighteen children (2205 boys and 2313 girls) aged between 6 to 59 months were sampled in the 2011 Demographic Health Survey (DHS) database. Body Mass Index (BMI) z-scores based on WHO 2006 reference population was chosen to estimate overweight (BMI z-score > 2) and obesity (BMI for age > 3). Regression analyses were performed to investigate risk factors of overweight/obesity. Results The prevalence of overweight and obesity was 8% (1.7% for obesity alone). Boys were more affected by overweight than girls with a prevalence of 9.7% and 6.4% respectively. The highest prevalence of overweight was observed in the Grassfield area (including people living in West and North-West regions) (15.3%). Factors that were independently associated with overweight and obesity included: having overweight mother (adjusted odds ratio (aOR) = 1.51; 95% CI 1.15 to 1.97) and obese mother (aOR = 2.19; 95% CI = 155 to 3.07), compared to having normal weight mother; high birth weight (aOR = 1.69; 95% CI 1.24 to 2.28) compared to normal birth weight; male gender (aOR = 1.56; 95% CI 1.24 to 1.95); low birth rank (aOR = 1.35; 95% CI 1.06 to 1.72); being aged between 13–24 months (aOR = 1.81; 95% CI = 1.21 to 2.66) and 25–36 months (aOR = 2.79; 95% CI 1.93 to 4.13) compared to being aged 45 to 49 months; living in the grassfield area (aOR = 2.65; 95% CI = 1.87 to 3.79) compared to living in Forest area. Muslim appeared as a protective factor (aOR = 0.67; 95% CI 0.46 to 0.95).compared to Christian religion. Conclusion This study underlines a high prevalence of early childhood overweight with significant disparities between ecological areas of Cameroon. Risk factors of overweight included high maternal BMI, high

  2. Prevalence and Risk Factors of Overweight and Obesity among Children Aged 6-59 Months in Cameroon: A Multistage, Stratified Cluster Sampling Nationwide Survey.

    Science.gov (United States)

    Tchoubi, Sébastien; Sobngwi-Tambekou, Joëlle; Noubiap, Jean Jacques N; Asangbeh, Serra Lem; Nkoum, Benjamin Alexandre; Sobngwi, Eugene

    2015-01-01

    Childhood obesity is one of the most serious public health challenges of the 21st century. The prevalence of overweight and obesity among children (overweight and obesity among children aged 6 months to 5 years in Cameroon in 2011. Four thousand five hundred and eighteen children (2205 boys and 2313 girls) aged between 6 to 59 months were sampled in the 2011 Demographic Health Survey (DHS) database. Body Mass Index (BMI) z-scores based on WHO 2006 reference population was chosen to estimate overweight (BMI z-score > 2) and obesity (BMI for age > 3). Regression analyses were performed to investigate risk factors of overweight/obesity. The prevalence of overweight and obesity was 8% (1.7% for obesity alone). Boys were more affected by overweight than girls with a prevalence of 9.7% and 6.4% respectively. The highest prevalence of overweight was observed in the Grassfield area (including people living in West and North-West regions) (15.3%). Factors that were independently associated with overweight and obesity included: having overweight mother (adjusted odds ratio (aOR) = 1.51; 95% CI 1.15 to 1.97) and obese mother (aOR = 2.19; 95% CI = 155 to 3.07), compared to having normal weight mother; high birth weight (aOR = 1.69; 95% CI 1.24 to 2.28) compared to normal birth weight; male gender (aOR = 1.56; 95% CI 1.24 to 1.95); low birth rank (aOR = 1.35; 95% CI 1.06 to 1.72); being aged between 13-24 months (aOR = 1.81; 95% CI = 1.21 to 2.66) and 25-36 months (aOR = 2.79; 95% CI 1.93 to 4.13) compared to being aged 45 to 49 months; living in the grassfield area (aOR = 2.65; 95% CI = 1.87 to 3.79) compared to living in Forest area. Muslim appeared as a protective factor (aOR = 0.67; 95% CI 0.46 to 0.95).compared to Christian religion. This study underlines a high prevalence of early childhood overweight with significant disparities between ecological areas of Cameroon. Risk factors of overweight included high maternal BMI, high birth weight, male gender, low birth rank

  3. Board Directors' Selection Process Following a Gender Quota

    DEFF Research Database (Denmark)

    Sigurjonsson, Olaf; Arnardottir, Audur Arna

    -quota selection of new board directors as well as the attitudes of board members towards the quota and perceptions of the effect of quota on processes. We incorporate a dual qualitative and quantitative methodology with in-depth interviews with 20 board directors and chairs, and a survey of 260 directors who...... companies with 50 or more employees. Thereby legislatively going further than any other country, out of the fifteen that have amended and adopted gender quota legislation. This article utilizes resource dependency and status expectations theory lenses to explore how the new legislation affected the post...... conviction. Furthermore, there are different avenues to the board. Although initial attitudes towards quotas are more negative among men than women, these attitudes decrease over time. Finally, consistent with status expectation theory, male directors are more negative than their female counterparts about...

  4. Mastering the market of CO2 emission quotas

    International Nuclear Information System (INIS)

    2004-05-01

    On January 1, 2005, a system of trade of carbon dioxide emission quotas, also called 'market of tradable emission permits', will be implemented in the European Union. This system is one of the 3 flexibility mechanisms foreseen by the Kyoto protocol in order to reduce the global economic cost of the fight against climatic change. The aim of this seminar is to clarify the process of transfer of the European directive into French law. It comprises 8 presentations dealing with: the objectives of tradable emission quotas (greenhouse effect, Kyoto commitments, short and long term stakes); presentation of the European directive about the trade system of greenhouse gas emissions; transposition of the directive into French law (fields of application, sectors and facilities concerned, possible exemptions, first national plan of quotas allocation); voluntary emission abatement commitments by industrial companies member of the AERES; quotas recording and management, control of trades; companies strategy (investment for CO 2 abatement or purchase of quotas, impact on industries and competitiveness); experience feedback of emission quotas trading in foreign countries (international CO 2 market development); CO 2 emission quotas linked with cogeneration (emissions from cogeneration facilities, possible allocation, impact for cogeneration companies, approaches in other European countries in this domain); perspectives and conclusions. (J.S.)

  5. The stratified Boycott effect

    Science.gov (United States)

    Peacock, Tom; Blanchette, Francois; Bush, John W. M.

    2005-04-01

    We present the results of an experimental investigation of the flows generated by monodisperse particles settling at low Reynolds number in a stably stratified ambient with an inclined sidewall. In this configuration, upwelling beneath the inclined wall associated with the Boycott effect is opposed by the ambient density stratification. The evolution of the system is determined by the relative magnitudes of the container depth, h, and the neutral buoyancy height, hn = c0(ρp-ρf)/|dρ/dz|, where c0 is the particle concentration, ρp the particle density, ρf the mean fluid density and dρ/dz Boycott layer transports dense fluid from the bottom to the top of the system; subsequently, the upper clear layer of dense saline fluid is mixed by convection. For sufficiently strong stratification, h > hn, layering occurs. The lowermost layer is created by clear fluid transported from the base to its neutral buoyancy height, and has a vertical extent hn; subsequently, smaller overlying layers develop. Within each layer, convection erodes the initially linear density gradient, generating a step-like density profile throughout the system that persists after all the particles have settled. Particles are transported across the discrete density jumps between layers by plumes of particle-laden fluid.

  6. Gender discrimination before mandated quotas? Evidence from Norway: 1989 to 2002

    OpenAIRE

    Strøm, Øystein R.

    2015-01-01

    Is the low percentage of women on boards due to discrimination? Discrimination has a time dimension; it is repeated period after period and is thus highly persistent. This persistence is tested with data from Norway before quota regulations were instituted in 2003. The data consist of an unbalanced panel sample of all non-financial listed companies from 1989 to 2002. Persistence implies a serial correlation close to one. The main finding is low persistence, implying no discrimination in the s...

  7. Methodology Series Module 5: Sampling Strategies.

    Science.gov (United States)

    Setia, Maninder Singh

    2016-01-01

    Once the research question and the research design have been finalised, it is important to select the appropriate sample for the study. The method by which the researcher selects the sample is the ' Sampling Method'. There are essentially two types of sampling methods: 1) probability sampling - based on chance events (such as random numbers, flipping a coin etc.); and 2) non-probability sampling - based on researcher's choice, population that accessible & available. Some of the non-probability sampling methods are: purposive sampling, convenience sampling, or quota sampling. Random sampling method (such as simple random sample or stratified random sample) is a form of probability sampling. It is important to understand the different sampling methods used in clinical studies and mention this method clearly in the manuscript. The researcher should not misrepresent the sampling method in the manuscript (such as using the term ' random sample' when the researcher has used convenience sample). The sampling method will depend on the research question. For instance, the researcher may want to understand an issue in greater detail for one particular population rather than worry about the ' generalizability' of these results. In such a scenario, the researcher may want to use ' purposive sampling' for the study.

  8. Methodology series module 5: Sampling strategies

    Directory of Open Access Journals (Sweden)

    Maninder Singh Setia

    2016-01-01

    Full Text Available Once the research question and the research design have been finalised, it is important to select the appropriate sample for the study. The method by which the researcher selects the sample is the 'Sampling Method'. There are essentially two types of sampling methods: 1 probability sampling – based on chance events (such as random numbers, flipping a coin etc.; and 2 non-probability sampling – based on researcher's choice, population that accessible & available. Some of the non-probability sampling methods are: purposive sampling, convenience sampling, or quota sampling. Random sampling method (such as simple random sample or stratified random sample is a form of probability sampling. It is important to understand the different sampling methods used in clinical studies and mention this method clearly in the manuscript. The researcher should not misrepresent the sampling method in the manuscript (such as using the term 'random sample' when the researcher has used convenience sample. The sampling method will depend on the research question. For instance, the researcher may want to understand an issue in greater detail for one particular population rather than worry about the 'generalizability' of these results. In such a scenario, the researcher may want to use 'purposive sampling' for the study.

  9. OPEC production ceilings and quotas: an analytical review

    International Nuclear Information System (INIS)

    Bakhtiari, A.M.S.

    1992-01-01

    After the onset of Gulf hostilities in August 1990, oil production, equivalent to some five million barrels per day, dried up. With two major exporters, Iraq and Kuwait, out of contention, other OPEC Members were suddenly free to produce and export at will. For the rest of 1990 and the whole of 1991, the issue of quotas was put on the backburner. Hence, the present analytical paper on past OPEC production quota agreements has been prepared. It is an attempt to correlate individual OPEC quotas with meaningful and tangible variables, using a curve-fitting computer programme. The main endeavour in this project is to find either a theoretical or an empirical basis for the generation of OPEC quotas. (author)

  10. National plan of allocation of CO2 emission quotas

    International Nuclear Information System (INIS)

    2006-01-01

    The directive 2003/87/CE of the European parliament and council from October 13, 2003 establishes a trading system of CO 2 emission quotas for some companies of the energy generation industry, of the manufacturing industry and of services. These quotas are tradable and negotiable and an initial amount of quotas is allocated to these companies according to their facilities in concern. The national plan of quotas allocation must precise the total amount of tradable emissions and its share among the different sectors of activity and facilities. The first project of allocation plan was transmitted to the European Commission on July 6, 2004 after its public consultation between June 8 and June 29 2004. Modifications have been added to meet the requests of the Commission and the French plan was finally approved on December 17, 2004 for an annual amount of 156.51 Mt of CO 2 quotas during the 2005-2007 period. This paper precises the modifications requested by the commission, the modifications of the French juridical system necessary to complete the implementation of the French part of the European quotas trading system, the elaboration of the next allocation plan for the 2008-2012 period, and the link between the European emissions trading system and the 'joint implementation' and 'clean development ' mechanisms implemented by the Kyoto protocol. (J.S.)

  11. Methodology Series Module 5: Sampling Strategies

    Science.gov (United States)

    Setia, Maninder Singh

    2016-01-01

    Once the research question and the research design have been finalised, it is important to select the appropriate sample for the study. The method by which the researcher selects the sample is the ‘ Sampling Method’. There are essentially two types of sampling methods: 1) probability sampling – based on chance events (such as random numbers, flipping a coin etc.); and 2) non-probability sampling – based on researcher's choice, population that accessible & available. Some of the non-probability sampling methods are: purposive sampling, convenience sampling, or quota sampling. Random sampling method (such as simple random sample or stratified random sample) is a form of probability sampling. It is important to understand the different sampling methods used in clinical studies and mention this method clearly in the manuscript. The researcher should not misrepresent the sampling method in the manuscript (such as using the term ‘ random sample’ when the researcher has used convenience sample). The sampling method will depend on the research question. For instance, the researcher may want to understand an issue in greater detail for one particular population rather than worry about the ‘ generalizability’ of these results. In such a scenario, the researcher may want to use ‘ purposive sampling’ for the study. PMID:27688438

  12. European Sugar Market – Impact of Quota System

    Directory of Open Access Journals (Sweden)

    Irena Benešová

    2015-01-01

    Full Text Available The European agricultural market has been criticized for its heavy regulations and subsidization. The sugar market is one of the most regulated ones; however, this will change radically in 2017 when the current system of production quotas will end. The aim of this paper is to present the basic characteristics of the EU quota sugar market. The analysis identifies the main drivers of EU sugar market and their position within the EU sugar market. The paper identifies especially those drivers/companies/alliances which take control over the EU sugar production realized under the quota production system. The paper also highlights the level of EU sugar market concentration and also identifies those countries and companies which are the main leaders in the sugar production area realized under the quota system. Based on the results deriving from the paper, it is possible to characterize the EU sugar market as a heavily concentrated one – nearly 75% (10 mil. tonnes of the quota is controlled by five multinational companies only; these companies are operating more than 50% of all the available sugar plants located in the EU. These multinational alliances are also in control of the production capacities of their subsidiaries. In most countries, this causes serious problems as the given quota is controlled by one or two producers only. The EU sugar market is extremely concentrated especially if we take into consideration the location of each alliance’s headquarters. The majority of production capacities are under (the control of especially German and French companies. These two countries are also the main beneficiaries in relation to the EU sugar production quota system.

  13. From the broadest possible to the EU adapted quota system

    International Nuclear Information System (INIS)

    Rypdal, Kristin

    2004-01-01

    The Norwegian Government's proposal for a trading system for emission quotas from 2005 to 2007 will only comprise about 10 per cent of the Norwegian emissions. This proposal is far from agreeing with the recommendations of the members of the quota committee, who in 2000 recommended a system for trade with emission quotas as an important means of conforming to the Kyoto protocol in Norway in the period 2008 to 2012. The committee concluded that considerations of cost effectiveness, goal-oriented management and equal treatment dictate a broadest possible system. Such a system will guarantee that the emission is cut where the costs are least, and it will make it easier for Norway to meet the requirements of the Kyoto protocol

  14. Greenhouse gas quotas on the Norwegian continental shelf

    International Nuclear Information System (INIS)

    Torvanger, Asbjoern; Godal, Odd; Kolshus, Hans H.; Aaheim, Asbjoern

    2002-01-01

    This report discusses advantages and disadvantages of voluntary quota obligations in a greenhouse gas emissions trading system at the company level, and advantages and disadvantages associated with various initial allocation mechanisms in a quota system. The analysis is based on the situation for the Norwegian oil industry in an early Norwegian emissions trading system in the period 2005-2007, and on oil companies' participation in international emissions trading under the Kyoto Protocol in the period 2008-2012. The report has been commissioned by the Norwegian Oil Industry Association, and was written in the period March-April 2002. (author)

  15. Biomethane as a fuel. Quota transfer; Biomethan als Kraftstoff. Quotenuebertragung

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-15

    Biomethane from biomass replaces fossil natural gas. Just as natural gas, it can be easily used in the transport sector. The advantages of biomethane as a fuel are numerous: high contribution to climate protection, technically acceptable admixture, price advantage over gasoline, eligibility to the biofuel quota. This brochure provides information on: (a) Role of biomethane to meet the biofuel targets of the Federal Government; (b) Eligibility of biomethane to the biofuel quota; (c) Business models for marketing of biomethane as a fuel; (d) Benefits of bio-methane for various actors.

  16. Liability rules for international trading of greenhouse gas emissions quotas

    DEFF Research Database (Denmark)

    Haites, E.; Missfeldt, F.

    2001-01-01

    To reduce the costs of mitigating greenhouse gas emissions in accordance with the Kyoto protocol, international trades of emissions quotas are allowed. The revenue from the sale of quotas may exceed the sanctions for non-compliance if these penalties are weak or poorly enforced. Under...... these circumstances emissions trading enables a country to benefit financially through non-compliance. To counter non-compliance due to trading a range of liability proposals have been suggested. Using a simple global model, we analyze the economic and environmental performance of these proposals for the first...

  17. Economic Analysis of the Effects of the Expiry of the EU Milk Quota System

    NARCIS (Netherlands)

    Réquillart, V.; Bouamra-Mechemache, Z.; Jongeneel, R.

    2008-01-01

    This report has been prepared to provide a quantitative assessment of the impact of the abolition of EU milk quotas on the EU dairy sector, including the different policy approaches of gradual phasing out and abrupt abolition of milk quotas

  18. Export quotas and policy constraints in the Indian textile and garment industries

    OpenAIRE

    Kathuria, Sanjay; Bhardwaj, Anjali

    1998-01-01

    The Agreement on Textiles and Clothing will abolish all quota restrictions in trade in textiles and clothing by the year 2005. Dismantling the quota regime represents both an opportunity (for developing countries to expand exports) and a threat (because quotas will no longer guarantee markets and even the domestic market will be open to competition). Data about the real burden imposed by distorting but nontransparent policies under the quota regime are inadequate, so the authors interviewed t...

  19. Electromagnetic waves in stratified media

    CERN Document Server

    Wait, James R; Fock, V A; Wait, J R

    2013-01-01

    International Series of Monographs in Electromagnetic Waves, Volume 3: Electromagnetic Waves in Stratified Media provides information pertinent to the electromagnetic waves in media whose properties differ in one particular direction. This book discusses the important feature of the waves that enables communications at global distances. Organized into 13 chapters, this volume begins with an overview of the general analysis for the electromagnetic response of a plane stratified medium comprising of any number of parallel homogeneous layers. This text then explains the reflection of electromagne

  20. 78 FR 55099 - Established Aggregate Production Quotas for Schedule I and II Controlled Substances and...

    Science.gov (United States)

    2013-09-09

    ... aggregate production quotas, an additional 25% of the estimated medical, scientific, and research needs as... Production Quotas for Schedule I and II Controlled Substances and Established Assessment of Annual Needs for... initial 2014 aggregate production quotas for controlled substances in Schedules I and II of the Controlled...

  1. Stratified medicine and reimbursement issues

    NARCIS (Netherlands)

    Fugel, Hans-Joerg; Nuijten, Mark; Postma, Maarten

    2012-01-01

    Stratified Medicine (SM) has the potential to target patient populations who will most benefit from a therapy while reducing unnecessary health interventions associated with side effects. The link between clinical biomarkers/diagnostics and therapies provides new opportunities for value creation to

  2. Removing EU milk quotas, soft landing versus hard landing

    NARCIS (Netherlands)

    Bouamra-Mechemache, Z.; Jongeneel, R.; Réquillart, V.

    2008-01-01

    This paper analyses EU dairy policy reforms and mainly focus on EU milk quota removal scenarios. The model used to evaluate the scenario is a spatial equilibrium model of the dairy sector. It integrates the main competitor of the EU on world markets, Oceania, as well as the main importing regions in

  3. Quotas and intersectionality: ethnicity and gender in candidate selection

    NARCIS (Netherlands)

    Celis, K.; Erzeel, S.; Mügge, L.; Damstra, A.

    2014-01-01

    Gender equality is not fully realised when it is restricted to ethnic majority men and women. This article examines how gender quotas as a form of equality policy affect ethnic minority groups, in particular, the gender balance among ethnic minority candidates for political office. Our analysis

  4. Quota disputes and subsistence whaling in Qeqertarsuaq, Greenland

    DEFF Research Database (Denmark)

    Tejsner, Pelle

    2014-01-01

    In Qeqertarsuaq (Disco Island), northwest Greenland, local disputes about the allocation of annual whaling quotas for beluga and narwhals feature as a source of conflict between state-imposed categories of occupational and non-occupational hunters. The national authorities’ co-management regime...

  5. Research on the optimization of quota design in real estate

    Science.gov (United States)

    Sun, Chunling; Ma, Susu; Zhong, Weichao

    2017-11-01

    Quota design is one of the effective methods of cost control in real estate development project and widely used in the current real estate development project to control the engineering construction cost, but quota design have many deficiencies in design process. For this purpose, this paper put forward a method to achieve investment control of real estate development project, which combine quota design and value engineering(VE) at the stage of design. Specifically, it’s an optimizing for the structure of quota design. At first, determine the design limits by investment estimate value, then using VE to carry on initial allocation of design limits and gain the functional target cost, finally, consider the whole life cycle cost (LCC) and operational problem in practical application to finish complex correction for the functional target cost. The improved process can control the project cost more effectively. It not only can control investment in a certain range, but also make the project realize maximum value within investment.

  6. The Gender Quota Campaign in Sierra Leone: An Interview with ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2011-10-19

    Oct 19, 2011 ... What led you to study the question of quotas for women in positions of political office? ... They have to fight like men fight to get into parliament. ... If you are talking about sexual and reproductive rights that affect women, most ...

  7. The Irish legislative gender quota: The first election

    Directory of Open Access Journals (Sweden)

    Brennan Mary

    2017-05-01

    Full Text Available In 2012 legislative gender quotas were introduced as part of the Fine Gael/Labour coalition government’s political reform agenda. The legislation specifies that payments to political parties ‘shall be reduced by 50 per cent, unless at least 30 per cent of the candidates whose candidatures were authenticated by the qualified party at the preceding general election were women and at least 30 per cent were men’. The 30 per cent gender threshold came into effect at the 2016 general election. Research demonstrates that gender quotas work to increase women’s political descriptive representation, but to do so, political parties must engage with them in ‘goodwill’, be ‘wellintentioned’ or place women in ‘winnable seats’. This article examines if this was the case at the 2016 general election. Using statistics, as well as drawing from interviews with party strategists, the article assesses the impact of gender quotas on women’s candidate selection and election. We conclude that parties did embrace the spirit of the gender quota law but resistance remains.

  8. Quota System And Educational Reforms In Nigeria | Obielumani ...

    African Journals Online (AJOL)

    As a result of the multi-ethnic nature of Nigeria and the desire of all to have quality education as a way of breaking the barriers of poverty, disease and ignorance, the struggle to have access to education has become more aggressive hence the introduction of quota system policy by the Federal Government as an instrument ...

  9. Practical guidebook about the market of CO{sub 2} emission quotas; Guide pratique du marche des quotas d'emission de CO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    Since January 1, 2005, the European directive about the trading of CO{sub 2} emission quotas foresees the allocation of CO{sub 2} emission quotas to the industrial sectors that generate huge amounts of greenhouse gases (energy generation, cement, glass, steel-making, mineral and paper industries). A system of trading of CO{sub 2} quotas has been implemented and allows the companies to exchange, sale or purchase quotas in order to be conformable with the volume of CO{sub 2} they have been authorized to release in the atmosphere. This guidebook is a vade mecum of the management of emission quotas. It explains the actions of the international community in favor of the fight against greenhouse emissions, the 3 flexibility mechanisms, the French environmental policy, the European system of fight against climatic change, the CO{sub 2} quotas system and its practical implementation. (J.S.)

  10. Carbon quota price and CDM potentials after Marrakesh

    International Nuclear Information System (INIS)

    Wenying Chen

    2003-01-01

    The Kyoto Protocol sets quantified GHG emission reduction commitments for Annex I Parties. But their emission reduction requirements related to BAU projections, one of the key factors to effect on future carbon market, are uncertain. Both the decisions made in Bonn and Marrakesh would have further consequences for how the future carbon market will take shape. This paper, with application of the carbon emission reduction trading model, evaluates future carbon quota price and Clean Development Mechanism (CDM) potentials under different BAU projections, and does sensitivity analysis on carry-over of AAUs, CERs and ERUs, implementation rate, transaction cost, holding of CERs in Non-Annex I Parties, etc. to assess the impacts of relevant decisions of COP6-bis and COP7 on the carbon market. Under different BAU projections, future carbon quota price and CDM potentials could vary widely. Carry over of AAUs, CERs, ERUs, and holding of CERs in Non-Annex I Parties could raise both quota price and total CDM potentials considerably. Implementation rate could have big impacts on both carbon quota price and CDM potentials, especially for the cases formerly with relatively high CDM potentials, and it could also change the regional distribution of CDM potentials. Transaction cost's effect on the carbon market would be comparatively low, but would become unignorable in the market whose quota price is low. It would lead to a downward trend in price while upward in CDM potentials when increasing the implementation rate or lowering transaction cost. Withdrawal of USA would dramatically shrink carbon price and credit amount, and large numbers of hot air and sink credits would further greatly crowd out the CDM projects; carry over of AAUs, CERs and ERUs, holding of CERs in Non-Annex I Parties, prompt start of CDM projects, etc., would, however, enhance the total CDM credits to ensure more investment and technology flow to developing countries to promote their sustainable development

  11. Carbon quota price and CDM potentials after Marrakesh

    International Nuclear Information System (INIS)

    Chen Wenying

    2003-01-01

    The Kyoto Protocol sets quantified GHG emission reduction commitments for Annex I Parties. But their emission reduction requirements related to BAU projections, one of the key factors to effect on future carbon market, are uncertain. Both the decisions made in Bonn and Marrakesh would have further consequences for how the future carbon market will take shape. This paper, with application of the carbon emission reduction trading model, evaluates future carbon quota price and Clean Development Mechanism (CDM) potentials under different BAU projections, and does sensitivity analysis on carry-over of AAUs, CERs and ERUs, implementation rate, transaction cost, holding of CERs in Non-Annex I Parties, etc. to assess the impacts of relevant decisions of COP6-bis and COP7 on the carbon market. Under different BAU projections, future carbon quota price and CDM potentials could vary widely. Carry over of AAUs, CERs, ERUs, and holding of CERs in Non-Annex I Parties could raise both quota price and total CDM potentials considerably. Implementation rate could have big impacts on both carbon quota price and CDM potentials, especially for the cases formerly with relatively high CDM potentials, and it could also change the regional distribution of CDM potentials. Transaction cost's effect on the carbon market would be comparatively low, but would become unignorable in the market whose quota price is low. It would lead to a downward trend in price while upward in CDM potentials when increasing the implementation rate or lowering transaction cost. Withdrawal of USA would dramatically shrink carbon price and credit amount, and large numbers of hot air and sink credits would further greatly crowd out the CDM projects; carry over of AAUs, CERs and ERUs, holding of CERs in Non-Annex I Parties, prompt start of CDM projects, etc., would, however, enhance the total CDM credits to ensure more investment and technology flow to developing countries to promote their sustainable development

  12. 50 CFR 680.40 - Crab Quota Share (QS), Processor QS (PQS), Individual Fishing Quota (IFQ), and Individual...

    Science.gov (United States)

    2010-10-01

    ..., DEPARTMENT OF COMMERCE (CONTINUED) SHELLFISH FISHERIES OF THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA Quota... the Internet or requested from the Regional Administrator. (ii) An application for crab QS or PQS may... be notified by an IAD, that the applicant did not meet the burden of proof to change the information...

  13. The merits of non-tradable quotas as a domestic policy instrument to prevent firm closure

    International Nuclear Information System (INIS)

    Hagem, Cathrine

    2001-05-01

    There is a concern in many countries that a domestic tradable quota system for greenhouse gases, where all emitters must pay for their quotas, may lead to closures of emissions-intensive industrial companies. Allocating quotas free of charge to companies operating in competitive markets has been suggested as a means to reduce the likelihood of closures. Two different designs of quota systems are studied within a two-period model: one where the quotas given free of charge are tradable, and one where the quotas are non-tradable. The two quota systems are compared with respect to their ability both to induce the firms to implement investment in abatement technology and to prevent or postpone closures. (author)

  14. The Stratified Legitimacy of Abortions.

    Science.gov (United States)

    Kimport, Katrina; Weitz, Tracy A; Freedman, Lori

    2016-12-01

    Roe v. Wade was heralded as an end to unequal access to abortion care in the United States. However, today, despite being common and safe, abortion is performed only selectively in hospitals and private practices. Drawing on 61 interviews with obstetrician-gynecologists in these settings, we examine how they determine which abortions to perform. We find that they distinguish between more and less legitimate abortions, producing a narrative of stratified legitimacy that privileges abortions for intended pregnancies, when the fetus is unhealthy, and when women perform normative gendered sexuality, including distress about the abortion, guilt about failure to contracept, and desire for motherhood. This stratified legitimacy can perpetuate socially-inflected inequality of access and normative gendered sexuality. Additionally, we argue that the practice by physicians of distinguishing among abortions can legitimate legislative practices that regulate and restrict some kinds of abortion, further constraining abortion access. © American Sociological Association 2016.

  15. RADIAL STABILITY IN STRATIFIED STARS

    International Nuclear Information System (INIS)

    Pereira, Jonas P.; Rueda, Jorge A.

    2015-01-01

    We formulate within a generalized distributional approach the treatment of the stability against radial perturbations for both neutral and charged stratified stars in Newtonian and Einstein's gravity. We obtain from this approach the boundary conditions connecting any two phases within a star and underline its relevance for realistic models of compact stars with phase transitions, owing to the modification of the star's set of eigenmodes with respect to the continuous case

  16. Boards and the Selection Procedures Post Gender Quotas

    DEFF Research Database (Denmark)

    Arna Arnardóttir, Auður; Sigurjonsson, Olaf; Terjesen, Siri

    Purpose: Director Selection process can greatly effect board’s behavior and effectiveness and ultimately the firm’s performance and outcome. Director selection practices are hence important and yet underresearched topic, especially practices applied in the wake of gender quota legislations....... The purpose of this paper is to contribute to the extant literature by gaining greater understanding into how new female board members are recruited and selected when demand for one gender is high. Design/methodology/approach: Mixed research methodology was applied. Questionnaire (N=260) and in......-depth interviews (N=20) were conducted with Icelandic non-executive board directors, to identify the selection criteria that are deemed most important when selecting the new female director candidates taking seat on boards in the wake of gender quota legislation and compare those practices with previous selection...

  17. Inequality in education and quotas for black students in universities

    Directory of Open Access Journals (Sweden)

    Eunice R. Durham

    Full Text Available This article discusses the proposed definition of quotas for black students in universities in view of the widespread inequalities in the Brazilian educational system. The author defends that the proposed measure would lead to limitations and distortions, for it is based on rigid, artificial categories, in sharp contrast with the country's ethnic heterogeneity, and fails to consider key factors in the schooling experience of afro-descendants. The study of statistical series has shown that in spite of the progress made, there is still a great educational gap dividing white students from black and mulatto students. This led the author to conclude that public initiatives geared to reinforcing basic skills would constitute a more effective affirmative action than the establishment of quotas.

  18. Price and welfare effects of emission quota allocation

    OpenAIRE

    Golombek, Rolf; Kittelsen, Sverre A.C.; Rosendahl, Knut Einar

    2011-01-01

    Abstracts with downloadable Discussion Papers in PDF are available on the Internet: http://www.ssb.no Abstract: We analyze how different ways of allocating emission quotas may influence the electricity market. Using a large-scale numerical model of the Western European energy market, we show that different allocation mechanisms can have very different effects on the electricity market, even if the total emission target is fixed. This is particularly the case if output-based alloca...

  19. Norwegian climate policy reforms in the presence of an international quota market

    International Nuclear Information System (INIS)

    Bjertnæs, Geir H.; Tsygankova, Marina; Martinsen, Thomas

    2013-01-01

    This study shows that the second-best optimal difference between tax rates on goods that generate greenhouse gas emissions and non-polluting goods is equal to the quota price plus a Ramsey tax on the quota price when emission quotas are traded between governments and the price elasticity of these goods is identical. This tax difference exceeds the second-best optimal difference between tax rates on goods that generate a negative externality equivalent to the quota price and non-polluting goods. Model simulations show that a unilateral increase in emission tax to above the international quota price generates a welfare gain for Norway. Model simulations also show that an international tax/quota price increase generates a welfare gain (loss) for Norway if Norwegian imports of oil become substantial (marginal) in the long run. - Highlights: • Higher second-best optimal emission tax rate with government quota trading • Optimal second-best emission tax rate exceeds the quota price. • Norwegian emission tax increase above international quota price boosts welfare. • International quota price increase boosts Norwegian welfare

  20. Free Falling in Stratified Fluids

    Science.gov (United States)

    Lam, Try; Vincent, Lionel; Kanso, Eva

    2017-11-01

    Leaves falling in air and discs falling in water are examples of unsteady descents due to complex interaction between gravitational and aerodynamic forces. Understanding these descent modes is relevant to many branches of engineering and science such as estimating the behavior of re-entry space vehicles to studying biomechanics of seed dispersion. For regularly shaped objects falling in homogenous fluids, the motion is relatively well understood. However, less is known about how density stratification of the fluid medium affects the falling behavior. Here, we experimentally investigate the descent of discs in both pure water and in stable linearly stratified fluids for Froude numbers Fr 1 and Reynolds numbers Re between 1000 -2000. We found that stable stratification (1) enhances the radial dispersion of the disc at landing, (2) increases the descent time, (3) decreases the inclination (or nutation) angle, and (4) decreases the fluttering amplitude while falling. We conclude by commenting on how the corresponding information can be used as a predictive model for objects free falling in stratified fluids.

  1. Stratified Medicine and Reimbursement Issues

    Directory of Open Access Journals (Sweden)

    Hans-Joerg eFugel

    2012-10-01

    Full Text Available Stratified Medicine (SM has the potential to target patient populations who will most benefit from a therapy while reducing unnecessary health interventions associated with side effects. The link between clinical biomarkers/diagnostics and therapies provides new opportunities for value creation to strengthen the value proposition to pricing and reimbursement (P&R authorities. However, the introduction of SM challenges current reimbursement schemes in many EU countries and the US as different P&R policies have been adopted for drugs and diagnostics. Also, there is a lack of a consistent process for value assessment of more complex diagnostics in these markets. New, innovative approaches and more flexible P&R systems are needed to reflect the added value of diagnostic tests and to stimulate investments in new technologies. Yet, the framework for access of diagnostic–based therapies still requires further development while setting the right incentives and appropriate align stakeholders interests when realizing long- term patient benefits. This article addresses the reimbursement challenges of SM approaches in several EU countries and the US outlining some options to overcome existing reimbursement barriers for stratified medicine.

  2. Information content of household-stratified epidemics

    Directory of Open Access Journals (Sweden)

    T.M. Kinyanjui

    2016-09-01

    Full Text Available Household structure is a key driver of many infectious diseases, as well as a natural target for interventions such as vaccination programs. Many theoretical and conceptual advances on household-stratified epidemic models are relatively recent, but have successfully managed to increase the applicability of such models to practical problems. To be of maximum realism and hence benefit, they require parameterisation from epidemiological data, and while household-stratified final size data has been the traditional source, increasingly time-series infection data from households are becoming available. This paper is concerned with the design of studies aimed at collecting time-series epidemic data in order to maximize the amount of information available to calibrate household models. A design decision involves a trade-off between the number of households to enrol and the sampling frequency. Two commonly used epidemiological study designs are considered: cross-sectional, where different households are sampled at every time point, and cohort, where the same households are followed over the course of the study period. The search for an optimal design uses Bayesian computationally intensive methods to explore the joint parameter-design space combined with the Shannon entropy of the posteriors to estimate the amount of information in each design. For the cross-sectional design, the amount of information increases with the sampling intensity, i.e., the designs with the highest number of time points have the most information. On the other hand, the cohort design often exhibits a trade-off between the number of households sampled and the intensity of follow-up. Our results broadly support the choices made in existing epidemiological data collection studies. Prospective problem-specific use of our computational methods can bring significant benefits in guiding future study designs.

  3. Information content of household-stratified epidemics.

    Science.gov (United States)

    Kinyanjui, T M; Pellis, L; House, T

    2016-09-01

    Household structure is a key driver of many infectious diseases, as well as a natural target for interventions such as vaccination programs. Many theoretical and conceptual advances on household-stratified epidemic models are relatively recent, but have successfully managed to increase the applicability of such models to practical problems. To be of maximum realism and hence benefit, they require parameterisation from epidemiological data, and while household-stratified final size data has been the traditional source, increasingly time-series infection data from households are becoming available. This paper is concerned with the design of studies aimed at collecting time-series epidemic data in order to maximize the amount of information available to calibrate household models. A design decision involves a trade-off between the number of households to enrol and the sampling frequency. Two commonly used epidemiological study designs are considered: cross-sectional, where different households are sampled at every time point, and cohort, where the same households are followed over the course of the study period. The search for an optimal design uses Bayesian computationally intensive methods to explore the joint parameter-design space combined with the Shannon entropy of the posteriors to estimate the amount of information in each design. For the cross-sectional design, the amount of information increases with the sampling intensity, i.e., the designs with the highest number of time points have the most information. On the other hand, the cohort design often exhibits a trade-off between the number of households sampled and the intensity of follow-up. Our results broadly support the choices made in existing epidemiological data collection studies. Prospective problem-specific use of our computational methods can bring significant benefits in guiding future study designs. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  4. The emissions of greenhouse gases are reduced by a new proposal for trade of quotas

    International Nuclear Information System (INIS)

    2004-01-01

    The emission quota system will stimulate enterprises that do not currently have to pay a CO 2 tax and which are not subjected to any other political instrument to cut their emissions of greenhouse gases. Consequently, the main part of the total Norwegian emission of greenhouse gases will be covered by climate policy instruments. The quota system enters into force on January 1, 2005, from which date the EU quota system will also be in force. The quota system will comprise CO 2 emissions from oil refineries, iron and steel manufacturers, producers of cement, lime, glass and ceramic products, and certain energy plants. Not all firms that are obliged to obtain quotas will receive as many quotas as they are expected to need. Norway introduced a CO 2 tax in 1991 and is among the countries with the strongest and most extensive political instruments against emission of greenhouse gases

  5. Suppression of stratified explosive interactions

    Energy Technology Data Exchange (ETDEWEB)

    Meeks, M.K.; Shamoun, B.I.; Bonazza, R.; Corradini, M.L. [Wisconsin Univ., Madison, WI (United States). Dept. of Nuclear Engineering and Engineering Physics

    1998-01-01

    Stratified Fuel-Coolant Interaction (FCI) experiments with Refrigerant-134a and water were performed in a large-scale system. Air was uniformly injected into the coolant pool to establish a pre-existing void which could suppress the explosion. Two competing effects due to the variation of the air flow rate seem to influence the intensity of the explosion in this geometrical configuration. At low flow rates, although the injected air increases the void fraction, the concurrent agitation and mixing increases the intensity of the interaction. At higher flow rates, the increase in void fraction tends to attenuate the propagated pressure wave generated by the explosion. Experimental results show a complete suppression of the vapor explosion at high rates of air injection, corresponding to an average void fraction of larger than 30%. (author)

  6. Green serves the dirtiest. On the interaction between black and green quotas

    Energy Technology Data Exchange (ETDEWEB)

    Boehringer, Christoph [Oldenburg Univ. (Germany). Dept. of Economics; Rosendahl, Knut Einar [Statistics Norway Research Department, Oslo (Norway)

    2009-10-15

    Tradable black (CO2) and green (renewables) quotas gain in popularity and stringency within climate policies of many OECD countries. The overlapping regulation through both instruments, however, may have important adverse economic implications. Based on stylized theoretical analysis and substantiated with numerical model simulations for the German electricity market, we show that a green quota imposed on top of a black quota does not only induce substantial excess cost but serves the dirtiest power technologies as compared to a black quota regime only. (orig.)

  7. Public and private in italian health care: trends and market quotas

    Directory of Open Access Journals (Sweden)

    Maria Michela Gianino

    2006-12-01

    Full Text Available

    Background: The Italian healthcare system has two components: public and private healthcare providers. Both deliver services on behalf of and payable by the national health care service. This study explores therelationships between public and private healthcare providers.

    Methods: The number of hospital admissions and length of stay or number of times the service was accessed stratified by year 2000, 2001, 2002; DRG; type of hospital admission (ordinary or day hospital/surgery; health provider category: public institutions without a specific reference territory, public institutions with a specific reference territory and accredited private institutions and medical or surgery DRGs. A distinction is made between those DRGs defined as belonging to the private sector and those falling within the public sector, assuming there is a majority market portion for services primarily supplied by the private sector. Case-mix index was utelised as the indicator for the complexity of the cases treated and the comparative performance index was used as the indicator for efficiency. Lastly in order to evaluate the services delivered with an inappropriate organizational profile reference is made the rulings defining Essential Level of assistance.

    Results: The results showed a shift in the reallocation of service volumes for ordinary admissions towards the private sector; the reallocation relates to the volumes but not to the types of cases treated, since the DRG mix remained substantially unchanged over the 3-year period and those DRG that absorb 51% of services were essentially constant. The private sector never achieved a market majority quota but rather controlled market niches with minority quotas. The private institutions treated less complex cases and worked with lower efficiency levels than the public sector. There was also a shift in the distribution of admissions from ordinary admissions to

  8. PHOTOSPHERIC EMISSION FROM STRATIFIED JETS

    International Nuclear Information System (INIS)

    Ito, Hirotaka; Nagataki, Shigehiro; Ono, Masaomi; Lee, Shiu-Hang; Mao, Jirong; Yamada, Shoichi; Pe'er, Asaf; Mizuta, Akira; Harikae, Seiji

    2013-01-01

    We explore photospheric emissions from stratified two-component jets, wherein a highly relativistic spine outflow is surrounded by a wider and less relativistic sheath outflow. Thermal photons are injected in regions of high optical depth and propagated until the photons escape at the photosphere. Because of the presence of shear in velocity (Lorentz factor) at the boundary of the spine and sheath region, a fraction of the injected photons are accelerated using a Fermi-like acceleration mechanism such that a high-energy power-law tail is formed in the resultant spectrum. We show, in particular, that if a velocity shear with a considerable variance in the bulk Lorentz factor is present, the high-energy part of observed gamma-ray bursts (GRBs) photon spectrum can be explained by this photon acceleration mechanism. We also show that the accelerated photons might also account for the origin of the extra-hard power-law component above the bump of the thermal-like peak seen in some peculiar bursts (e.g., GRB 090510, 090902B, 090926A). We demonstrate that time-integrated spectra can also reproduce the low-energy spectrum of GRBs consistently using a multi-temperature effect when time evolution of the outflow is considered. Last, we show that the empirical E p -L p relation can be explained by differences in the outflow properties of individual sources

  9. Why does Brazil need racial quotas? An analysis of the admission of quota students at the Universidade Estadual do Norte Fluminense / UENF

    Directory of Open Access Journals (Sweden)

    Ludmila Gonçalves da Matta

    2015-02-01

    Full Text Available This paper presents the results of a study about the quota system at the Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF. Quotas at UENF cover the following beneficiaries, after low-income verification: public school students, blacks, indigenous, people with physical disabilities, and children of police officers killed or disabled in the line of duty. The study focused on the comparative analysis of the 2008 and 2009 entrance examinations. The relationship between supply and demand for vacancies as well as the passing grades were analyzed. The analysis revealed that there is a greater demand for quotas in the courses in which the candidate/vacancy ratio is higher, and that quotas are unnecessary for approval in many courses.

  10. Higher education: free tuition vs. quotas vs. targeted vouchers

    Directory of Open Access Journals (Sweden)

    Eduardo de Carvalho Andrade

    2010-03-01

    Full Text Available This paper compares theoretically three alternative university systems: the current one adopted in Brazil, in which students who perform better in the entering exam obtain the right to attend the public university without paying the full tuition; a system of affirmative action quotas in public universities, to benefit low income students; and a targeted vouchers system that can be used either to pay private or public university tuiton. The comparison indicates that the last system leads to: (i a higher quality of the labor force; (ii a more efficient allocation of resources; and (iii a greater social mobility.Este trabalho compara, do ponto de vista teórico, três sistemas universitários alternativos: o atual adotado pelo Brasil, no qual os alunos das universidades públicas, que são praticamente gratuitas, são escolhidos através de um processo seletivo; um sistema de quotas nas universidades públicas para beneficiar estudantes de baixa renda; e um sistema de vouchers direcionados para estudantes de baixa renda que podem ser utilizados nas universidades privadas ou públicas. A comparação destes três sistemas indica que o último é o mais eficiente, pois gera: (i maior qualidade da mão de obra; (ii alocação mais eficiente dos recursos; e (iii maior mobilidade social.

  11. Russian quota sales: Free sale of ''hot air'' is not likely

    International Nuclear Information System (INIS)

    Moe, Arild

    2000-01-01

    The article discusses emission quota transactions and emission regulation measures related to the Kyoto protocol. The focus is on the problems in the Russian economy during the 1990s, the pollution aspects and their management and possible future developments in the economy. Problems with the quota management versus joint national and international action is mentioned

  12. 21 CFR 1303.22 - Procedure for applying for individual manufacturing quotas.

    Science.gov (United States)

    2010-04-01

    ... manufacturing quotas. Any person who is registered to manufacture any basic class of controlled substance listed in Schedule I or II and who desires to manufacture a quantity of such class shall apply on DEA Form 189 for a manufacturing quota for such quantity of such class. Copies of DEA Form 189 may be obtained...

  13. 21 CFR 1303.23 - Procedure for fixing individual manufacturing quotas.

    Science.gov (United States)

    2010-04-01

    ...) In fixing individual manufacturing quotas for a basic class of controlled substance listed in Schedule I or II, the Administrator shall allocate to each applicant who is currently manufacturing such... quotas for a basic class of controlled substance listed in Schedule I or II, the Administrator shall...

  14. 78 FR 37237 - Proposed Adjustments to the Aggregate Production Quotas for Schedule I and II Controlled...

    Science.gov (United States)

    2013-06-20

    ... class of controlled substance listed in schedules I and II and for ephedrine, pseudoephedrine, and... disposal by the registrants holding individual manufacturing quotas for the class; (2) whether any... the Aggregate Production Quotas for Schedule I and II Controlled Substances and Assessment of Annual...

  15. 76 FR 61074 - USDA Increases the Fiscal Year 2011 Tariff-Rate Quota for Refined Sugar

    Science.gov (United States)

    2011-10-03

    ... Quota for Refined Sugar AGENCY: Office of the Secretary, USDA. ACTION: Notice. SUMMARY: The Secretary of Agriculture today announced an increase in the fiscal year (FY) 2011 refined sugar tariff-rate quota (TRQ) of... INFORMATION: A quantity of 22,000 MTRV for sugars, syrups, and molasses (collectively referred to as refined...

  16. 7 CFR 1463.106 - Base quota levels for eligible tobacco producers.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Base quota levels for eligible tobacco producers... TOBACCO TRANSITION PROGRAM Tobacco Transition Payment Program § 1463.106 Base quota levels for eligible... farm's average yield for 2001, 2002, and 2003 to get the 2004 farm base pounds total. 2 Multiply any...

  17. CO2 emissions of installations concerned by the directive quotas 2003/87/CE

    International Nuclear Information System (INIS)

    2003-01-01

    This document provides data on the the carbon dioxide emissions: emissions of reference for the allocation (t CO 2 ), annual allocation of quotas (t CO 2 ), % of reduction for 2005-2007 against reference emissions, % of reduction for 2005-2007 against the 2002 emissions, allocation of quotas for the period 2005-2007 (t CO 2 ). (A.L.B.)

  18. 50 CFR 679.41 - Transfer of quota shares and IFQ.

    Science.gov (United States)

    2010-10-01

    ... Section 679.41 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND... ALASKA Individual Fishing Quota Management Measures § 679.41 Transfer of quota shares and IFQ. (a... from the QS holder's immediate family to receive survivorship transfer privileges in the event of the...

  19. 78 FR 29331 - Proposed Information Collection; Comment Request; Western Alaska Community Development Quota Program

    Science.gov (United States)

    2013-05-20

    ... before July 19, 2013. ADDRESSES: Direct all written comments to Jennifer Jessup, Departmental Paperwork... economies in western Alaska. CDQ and prohibited species quota (PSQ) allocations are made to CDQ groups.... Information is collected only through quota transfers in this collection. II. Method of Collection Respondents...

  20. Economic analysis of the Canada-United States softwood lumber dispute : playing the quota game

    NARCIS (Netherlands)

    Kooten, van G.C.

    2002-01-01

    The Canada-U.S. Softwood Lumber Agreement (SLA) was the latest measure to restrict Canadian exports of softwood lumber to the United States. Rather than a countervail duty or export tax, SLA employed a quota that provides a large windfall (quota) rent to Canadian lumber producers in addition to

  1. Analysing the Effects of a Pigs Production Quota within a Dynamic CGE Framework

    DEFF Research Database (Denmark)

    Adams, Philip D; Hansen, Lill Thanning; Jacobsen, Lars Bo

    2001-01-01

    In this paper we address the issue of timing and announcement within a dynamic applied general equilibrium model of the Danish economy. Specifically we analyse the introduction of a quota on the production of pigs. Two scenarios are analysed, namely the introduction of a once-off quota without any...

  2. Future policy options for EU beet production: quotas - yes or no?

    NARCIS (Netherlands)

    Smit, A.B.; Helming, J.F.M.

    2012-01-01

    Abolishment of EU sugar quotas will lead to lower sugar and sugar beet prices in the EU, leading to lower margins for farms. At the same time, expansion of sugar beet growing and processing in a quota-free situation can decrease fixed cost per ha of sugar beet and per kg of sugar, making both sugar

  3. The quest for human development and the concept of quota system ...

    African Journals Online (AJOL)

    It is believed that Nigeria as a nation, in the quest to achieve human development has adopted the concept of quota system. Quota system in the tertiary education ensures that all the federating units that make up Nigeria are represented in the admission process. This is necessitated by the multi-ethnic and multi-religious ...

  4. 77 FR 58969 - Fisheries of the Northeastern United States; Bluefish Fishery; Quota Transfer

    Science.gov (United States)

    2012-09-25

    .... 120201086-2418-02] RIN 0648-XC235 Fisheries of the Northeastern United States; Bluefish Fishery; Quota... North Carolina is transferring a portion of its 2012 commercial bluefish quota to the State of New... governing the bluefish fishery are found at 50 CFR part 648. The regulations require annual specification of...

  5. 76 FR 74009 - Fisheries of the Northeastern United States; Bluefish Fishery; Quota Transfer

    Science.gov (United States)

    2011-11-30

    .... 101228634-1149-02] RIN 0648-XA825 Fisheries of the Northeastern United States; Bluefish Fishery; Quota... a portion of its 2011 commercial bluefish quota to New York State. By this action, NMFS adjusts the... Specialist, (978) 281-9224. SUPPLEMENTARY INFORMATION: Regulations governing the bluefish fishery are found...

  6. 78 FR 64182 - Fisheries of the Northeastern United States; Bluefish Fishery; Quota Transfer

    Science.gov (United States)

    2013-10-28

    .... 130104009-3416-02] RIN 0648-XC921 Fisheries of the Northeastern United States; Bluefish Fishery; Quota... Jersey is transferring a portion of its 2013 commercial bluefish quota to the State of New York. By this... Management Specialist, 978-281-9224. SUPPLEMENTARY INFORMATION: Regulations governing the bluefish fishery...

  7. 78 FR 54399 - Fisheries of the Northeastern United States; Bluefish Fishery; Quota Transfer

    Science.gov (United States)

    2013-09-04

    .... 130104009-3416-02] RIN 0648-XC815 Fisheries of the Northeastern United States; Bluefish Fishery; Quota... North Carolina is transferring a portion of its 2013 commercial bluefish quota to the Commonwealth of... governing the bluefish fishery are found at 50 CFR part 648. The regulations require annual specification of...

  8. 77 FR 76424 - Fisheries of the Northeastern United States; Bluefish Fishery; Quota Transfer

    Science.gov (United States)

    2012-12-28

    .... 120201086-2418-02] RIN 0648-XC394 Fisheries of the Northeastern United States; Bluefish Fishery; Quota... Florida is transferring a portion of its 2012 commercial bluefish quota to the State of New York. By this... Management Specialist, 978-281-9224. SUPPLEMENTARY INFORMATION: Regulations governing the bluefish fishery...

  9. Quota regulation as energy political tool. Feasibility study; Kvoteregulering som energipolitisk virkemiddel. Konsekevensanalysen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-06-15

    The overall aim of the project was to determine what effect the energy policy introduced through the law on CO{sub 2}-quotas would have on the development the energy sector in Denmark. The energy policy is a market-based approach where the individual stakeholders choose how they will react within the boundaries of the allocated quotas. Options include the purchasing of quotas on the open market, investment in CDM/JI activities, the implementation of energy efficiency initiatives or fuel substitution. The focus of the study was on how the affected companies reacted to the implementation of a CO{sub 2}-quota. This was done by undertaking a series of interviews that resulted in a stakeholder analysis of companies encompassed by the CO2-quota law. A series of national consequences of the law on CO{sub 2}-quotas were then determined based on the stakeholder analysis. According to the results of the stakeholder analysis the following consequences were determined for the periods 2005-2007 and 2008-2012 as a result of quota regulation: 1) In the electricity sector no additional investments will be made in energy efficiency initiatives or fuel substitution projects than were already planned before quota regulation was introduced. 2) The heating sector will carry out isolated energy efficiency projects, but generally these are not socio-economically viable. 3) Industry will carry out isolated energy efficiency initiatives and renewable energy projects. Only 1.2 million tonnes of CO{sub 2} will be reduced annually through these initiatives compared to the estimated annual shortfall of 8 13 million tonnes CO{sub 2}. The shortfall will be made up through the purchase of quotas on the open market. This study indicates, therefore, that quota regulation will make a limited contribution to further initiatives in energy efficiency and renewable energy. If further energy efficiency initiatives are desired it will be necessary to implement other regulatory incentives. With regards to

  10. Dilemmas in the Danish Approach to Gender Quotas and Gender Equality

    DEFF Research Database (Denmark)

    Siim, Birte; Agustin, Lise Rolandsen

    The paper addresses the dilemmas, contradictions and paradoxes in the Danish approach to gender quotas and gender equality. Gender theory has presented diverse arguments for gender quota: justice, resources and women’s interests. Gender quota can be understood as a means to achieve gender parity...... and gender justice in all arenas of society political and economic life. The belief in gender theory and research has been that gender quota would and should be a means to achieve equal rights and gender equality. Recently a new discourse and rhetoric of profitability of gender equality within a range...... of institutions from business to higher education has become prominent in many arenas. One example is the Report on gender equality between men and women in the EU, which argues that gender quotas are not only beneficial for women’s rights but also for industry, for society, and for men...

  11. Preferences for government enforcement of a common pool harvest quota: Theory and experimental evidence from fishing communities in Colombia

    OpenAIRE

    Maria Alejandra Velez; John K. Stranlund; James J. Murphy

    2012-01-01

    We examine individual harvesters’ preferences for government enforcement of a quota imposed on the exploitation of a common pool resource. We develop a model of Nash behavior by identical risk neutral harvesters to explain individual equilibrium preferences for enforcement of an efficient harvest quota. If the quota is not enforced well, we demonstrate that individual harvesters will always prefer increased enforcement—either increased monitoring or increased penalties—of the quota. We conduc...

  12. Gender quotas for women in national politics: A comparative analysis across development thresholds.

    Science.gov (United States)

    Rosen, Jennifer

    2017-08-01

    Women's share of global lower or single house parliamentary seats has increased by over 70% over the course of the 21st century. Yet these increases have not been uniform across countries. Rather countries with low levels of socioeconomic development have outpaced developed democracies in terms of the gains made in the formal political representation of women. One reasonable explanation for this trend is the adoption in many poorer countries of national gender quota legislation, that is, affirmative action laws intended to compensate for sex discrimination in the electoral process. Yet, cross-national analyses examining quotas as an explanatory factor typically use a simple binary (yes/no) variable that either conflates the diverse intra-quota variations into a single variable or includes only one part of the many quota variations. By contrast, using an originally compiled dataset that includes 167 countries from 1992 to 2012, this paper employs measures of gender quota legislation that capture the complexity and considerable diversity of existing quota legislation. These measures allow us to identify the specific factors that have helped so many less developed countries rise to the top of international rankings in recent years. The findings indicate that the effect of each type of gender quota, as well as other explanatory variables, do not operate in the same way across all countries. Specifically, voluntary political party quotas are substantially more effective in developed countries, while reserved seat quotas are only significant in least developed countries. Electoral candidate quotas, on the other hand, can be significant across all countries, however only have a positive effect when they are accompanied by placement mandates that ensure women are placed in winnable positions, sanctions for non-compliance that are significant enough to force adherence, and a minimum mandated threshold of at least 30%. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. 75 FR 47258 - Determination of Total Amounts of Fiscal Year 2011 Tariff-Rate Quotas for Raw Cane Sugar and...

    Science.gov (United States)

    2010-08-05

    ... Determination of Total Amounts of Fiscal Year 2011 Tariff-Rate Quotas for Raw Cane Sugar and Certain Sugars...) 2011 in-quota aggregate quantity of the raw, as well as, refined and specialty sugar Tariff-Rate Quotas (TRQ) as required under the U.S. World Trade Organization (WTO) commitments. The FY 2011 raw cane sugar...

  14. 76 FR 21418 - Fiscal Year 2011 Allocation of Additional Tariff-Rate Quota Volume for Raw Cane Sugar and...

    Science.gov (United States)

    2011-04-15

    ...-Rate Quota Volume for Raw Cane Sugar and Reallocation of Unused Fiscal Year 2011 Tariff-Rate Quota Volume for Raw Cane Sugar AGENCY: Office of the United States Trade Representative. ACTION: Notice...) for imported raw cane sugar and of country-by-country reallocations of the FY 2011 in-quota quantity...

  15. 77 FR 25012 - Fiscal Year 2012 Allocation of Additional Tariff-Rate Quota Volume for Raw Cane Sugar and...

    Science.gov (United States)

    2012-04-26

    ...-Rate Quota Volume for Raw Cane Sugar and Reallocation of Unused Fiscal Year 2012 Tariff-Rate Quota Volume for Raw Cane Sugar AGENCY: Office of the United States Trade Representative. ACTION: Notice...) for imported raw cane sugar and of country-by-country reallocations of the FY 2012 in-quota quantity...

  16. 78 FR 47580 - Fisheries of the Northeastern United States; Scup Fishery; Adjustment to the 2013 Winter II Quota

    Science.gov (United States)

    2013-08-06

    ... the 2013 Winter II Quota AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... adjusts the 2013 Winter II commercial scup quota. This action complies with Framework Adjustment 3 to the... the rollover of unused commercial scup quota from the Winter I period to the Winter II period. DATES...

  17. 77 FR 52624 - Fisheries of the Northeastern United States; Scup Fishery; Adjustment to the 2012 Winter II Quota

    Science.gov (United States)

    2012-08-30

    ... the 2012 Winter II Quota AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... adjusts the 2012 Winter II commercial scup quota. This action complies with Framework Adjustment 3 to the... the rollover of unused commercial scup quota from the Winter I period to the Winter II period. DATES...

  18. 75 FR 54290 - Fisheries of the Northeastern United States; Scup Fishery; Adjustment to the 2010 Winter II Quota

    Science.gov (United States)

    2010-09-07

    ... the 2010 Winter II Quota AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... adjusts the 2010 Winter II commercial scup quota. This action complies with Framework Adjustment 3... process to allow the rollover of unused commercial scup quota from the Winter I period to the Winter II...

  19. 76 FR 47491 - Fisheries of the Northeastern United States; Scup Fishery; Adjustment to the 2011 Winter II Quota

    Science.gov (United States)

    2011-08-05

    ... the 2011 Winter II Quota AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... adjusts the 2011 Winter II commercial scup quota. This action complies with Framework Adjustment 3... process to allow the rollover of unused commercial scup quota from the Winter I period to the Winter II...

  20. Women’s Representation in Politics in South Eastern Europe : Quotas and the Importance of Party Differences

    NARCIS (Netherlands)

    Rashkova, E.; Zankina, Emilia

    2017-01-01

    Quotas are determined to be the main and most effective tool in promoting gender equality. We examine six Southeast European countries where quotas have been either reintroduced (following the abolition of communist-era quota systems) or introduced for the first time. Presenting original data on the

  1. Classification of archaeologically stratified pumice by INAA

    International Nuclear Information System (INIS)

    Peltz, C.; Bichler, M.

    2001-01-01

    In the framework of the research program 'Synchronization of Civilization in the Eastern Mediterranean Region in the 2nd Millenium B.C.' instrumental neutron activation analysis (INAA) was used to determine 30 elements in pumice from archaeological excavations to reveal their specific volcanic origin. The widespread pumiceous products of several eruptions in the Aegean region were used as abrasive tools and were therefore popular trade objects. A remarkable quantity of pumice and pumiceous tephra (several km 3 ) was produced by the 'Minoan eruption' of Thera (Santorini), which is assumed to have happened between 1450 and 1650 B.C. Thus the discovery of the primary fallout of 'Minoan' tephra in archaeologically stratified locations can be used as a relative time mark. Additionally, pumice lumps used as abrasive can serve for dating by first appearance. Essential to an identification of the primary volcanic source is the knowledge that pumices from the Aegean region can easily be distinguished by their trace element distribution patterns, as previous work has shown. The elements Al, Ba, Ca, Ce, Co, Cr, Cs, Dy, Eu, Fe, Hf, K, La, Lu, Mn, Na, Nd, Rb, Sb, Sc, Sm, Ta, Tb, Th, Ti, U, V, Yb, Zn and Zr were determined in 16 samples of pumice lumps from excavations in Tell-el-Dab'a and Tell-el-Herr (Egypt). Two irradiation cycles and five measurement runs were applied. A reliable identification of the samples is achieved by comparing these results to the database compiled in previous studies. (author)

  2. The implementing of the CO2 quotas system most of the enterprises reduced their emissions intensity

    International Nuclear Information System (INIS)

    2007-05-01

    In 2005, first year of its implementing, the system of the european CO 2 exchange quotas concerned 600 enterprises in France. For 20 euros the ton of CO 2 , the allocated quotas represent 1,2% of the enterprises turnover. But the repartition appears very disparate in accordance with the sectors and the enterprise size. The authors presents the system and analyze the results for the year 2005 in France showing that main of the enterprises exceed the quotas allocation. (A.L.B.)

  3. Evaluating the Results of Quota Systems in Politics in Latin America

    Directory of Open Access Journals (Sweden)

    Mala Htun

    2001-01-01

    Full Text Available This article discusses the varying effects of quota systems, as they emerge from a scenario of women’s increased inroads into politics in Latin America, expressed in the increased number of women in elected offices, the implementation of quota systems and increased presence of the issue of gender equality in political agendas. The character of the electoral system, as based on “open” or “closed” lists; the absence or presence of a norm of a compulsory competitive position for women within political parties and political parties’ commitment to quota policies are the crucial factors that determine variation.

  4. Sampling

    CERN Document Server

    Thompson, Steven K

    2012-01-01

    Praise for the Second Edition "This book has never had a competitor. It is the only book that takes a broad approach to sampling . . . any good personal statistics library should include a copy of this book." —Technometrics "Well-written . . . an excellent book on an important subject. Highly recommended." —Choice "An ideal reference for scientific researchers and other professionals who use sampling." —Zentralblatt Math Features new developments in the field combined with all aspects of obtaining, interpreting, and using sample data Sampling provides an up-to-date treat

  5. 76 FR 78044 - Controlled Substances: Established Aggregate Production Quotas for 2012

    Science.gov (United States)

    2011-12-15

    ... substances into the illicit market. Through the quota system, DEA limits the amount of those substances and... Betacetylmethadol 2 g Beta-hydroxy-3-methylfentanyl 2 g Beta-hydroxyfentanyl 2 g Betameprodine 2 g Betamethadol 2 g...

  6. Catch-Quota Management - an example of result based fisheries management

    DEFF Research Database (Denmark)

    Kirkegaard, Eskild; Schou, Mogens; Dalskov, Jørgen

    The European Commission tabled in July 2011 a proposal for a revision of the Common Fisheries Policy (CFP). A central element of the revision is the introduction of a quota management system where all fish caught count against the quotas. The principle of full accountability of the catch...... is a complete change from present management where only the fish landed count against the quotas. The principle of full accountability opens for the introduction of a result based fisheries management strategy, where a fishery is regulated by clearly stated results and the fisher enjoys a maximum of freedom...... to plan and conduct the fishing operation to meet these results. Experiences from Danish trials with Catch Quota Management (CQM) conducted in 2008 to 2012 is presented and the possibilities of simplifying the current EU fisheries management and control regulations under a CQM system are evaluated...

  7. 21 CFR 1315.22 - Procedure for applying for individual manufacturing quotas.

    Science.gov (United States)

    2010-04-01

    ... factors that the applicant finds relevant to the fixing of the individual manufacturing quota, including... economic and physical availability of raw materials for use in manufacturing and for inventory purposes...

  8. Resource control in ATLAS distributed data management: Rucio Accounting and Quotas

    CERN Document Server

    Barisits, Martin-Stefan; The ATLAS collaboration; Garonne, Vincent; Lassnig, Mario; Beermann, Thomas Alfons; Vigne, Ralph

    2015-01-01

    The ATLAS Distributed Data Management system manages more than 160PB of physics data across more than 130 sites globally. Rucio, the next generation Distributed Data Management system of the ATLAS experiment, replaced DQ2 in December 2014 and will manage the experiments data throughout Run 2 of the LHC and beyond. The previous data management system pursued a rather simplistic approach for resource management, but with the increased data volume and more dynamic handling of data workflows required by the experiment, a more elaborate approach to this issue is needed. Rucio was delivered with an initial quota system, but during the first months of operation it turned out to not fully satisfy the collaborations resource management needs. We consequently introduce a new concept of declaring quota policies (limits) for accounts in Rucio. This new quota concept is based on accounts and RSE (Rucio storage element) expressions, which allows the definition of hierarchical quotas in a dynamic way. This concept enables t...

  9. Introduction of the Quota System in Sudan and its Impact on ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    1 mars 2011 ... In the latest general election, a 25% women's quota was agreed upon and implemented. ... and its impact on women's engagement in politics both within political parties and in general. ... Bulletin de BRAS - Janvier 2018.

  10. The interaction between the energy markets and the CO2 quota market

    International Nuclear Information System (INIS)

    Jensen, Trond

    2006-01-01

    The article briefly discusses the results of a new power market analysis and points out that the quota trade contributes to increased costs in the fossil power production. The role of the power demanding industry is reviewed

  11. Prototypic Features of Loneliness in a Stratified Sample of Adolescents

    DEFF Research Database (Denmark)

    Lasgaard, Mathias; Elklit, Ask

    2009-01-01

    Dominant theoretical approaches in loneliness research emphasize the value of personality characteristics in explaining loneliness. The present study examines whether dysfunctional social strategies and attributions in lonely adolescents can be explained by personality characteristics...... guidance and intervention. Thus, professionals need to be knowledgeable about prototypic features of loneliness in addition to employing a pro-active approach when assisting adolescents who display prototypic features....

  12. Impacts of Renewable Energy Quota System on China's Future Power Sector

    OpenAIRE

    Xiong, Weiming; Zhang, Da; Mischke, Peggy; Zhang, Xiliang

    2014-01-01

    As the biggest carbon emitting sector which produces 44% of current national carbon emission in China, the coal-dominated power sector has a tremendous potential for CO2 mitigation in the next two decades. Renewable energy quota system is currently discussed as a potential future policy instrument for the power sector, which requires certain fraction of renewable energy in total power generation for each province and grid zone. The quantitative studies on renewable energy quota for China are ...

  13. Dilemmas in the Danish approach to gender equality : gender equality without gender quota

    OpenAIRE

    ROLANDSEN AGUSTÍN, Lise; SIIM, Birte

    2015-01-01

    The paper addresses the dilemmas, contradictions and paradoxes in the Danish approach to gender quotas and gender equality and discusses the intersections of citizenship, democracy and gender justice. Gender research understands gender quota as a means to achieve equal rights, gender equality and gender parity. Gender theory has conceptualized gender parity as one step towards achieving gender justice in all arenas of social, political and economic life. The Danish cases illustrate that conte...

  14. Regional allocation of carbon emission quotas in China: Evidence from the Shapley value method

    International Nuclear Information System (INIS)

    Zhang, Yue-Jun; Wang, Ao-Dong; Da, Ya-Bin

    2014-01-01

    It is an important task for China to allocate carbon emission quotas among regions so as to realize its carbon reduction targets and establish the national cap-and-trade carbon market. Meanwhile, it is supposed to be cost-effective to jointly reduce China's carbon emissions through some collaborative activities among regions. Then a natural question is how to allocate the quotas among regions in light of the collaboration. For this purpose, the Shapley value method is adopted and the results show that, first, the regions with higher GDP, higher carbon outflow and higher carbon reduction connection should be allocated more carbon quotas. Moreover, when the collaboration is considered, the optimal allocation of carbon quotas among regions will change significantly compared to the basic quotas by the entropy method; and the Central region is allocated the largest proportion of carbon quota among regions, which indicates its largest radiation effect. Besides, the collaboration between the Central region and Northern coast region, and that between the Central region and the Eastern region should be paid close attention. These results may provide insightful support for decision makers to promote collaborative carbon reduction and allocate carbon quotas in China. - Highlights: • The paper allocates carbon quotas given the collaboration among regions in China. • The Shapley value method coupled with the entropy and gravity models is adopted. • The regions with higher GDP, carbon outflow and reduction connection allocate more. • The Central region has the largest radiation effect on others among all regions. • The collaboration of the Central and Northern coast regions should have priority

  15. Grain distinct stratified nanolayers in aluminium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Donatus, U., E-mail: uyimedonatus@yahoo.com [School of Materials, The University of Manchester, Manchester, M13 9PL, England (United Kingdom); Thompson, G.E.; Zhou, X.; Alias, J. [School of Materials, The University of Manchester, Manchester, M13 9PL, England (United Kingdom); Tsai, I.-L. [Oxford Instruments NanoAnalysis, HP12 2SE, High Wycombe (United Kingdom)

    2017-02-15

    The grains of aluminium alloys have stratified nanolayers which determine their mechanical and chemical responses. In this study, the nanolayers were revealed in the grains of AA6082 (T6 and T7 conditions), AA5083-O and AA2024-T3 alloys by etching the alloys in a solution comprising 20 g Cr{sub 2}O{sub 3} + 30 ml HPO{sub 3} in 1 L H{sub 2}O. Microstructural examination was conducted on selected grains of interest using scanning electron microscopy and electron backscatter diffraction technique. It was observed that the nanolayers are orientation dependent and are parallel to the {100} planes. They have ordered and repeated tunnel squares that are flawed at the sides which are aligned in the <100> directions. These flawed tunnel squares dictate the tunnelling corrosion morphology as well as appearing to have an affect on the arrangement and sizes of the precipitation hardening particles. The inclination of the stratified nanolayers, their interpacing, and the groove sizes have significant influence on the corrosion behaviour and seeming influence on the strengthening mechanism of the investigated aluminium alloys. - Highlights: • Stratified nanolayers in aluminium alloy grains. • Relationship of the stratified nanolayers with grain orientation. • Influence of the inclinations of the stratified nanolayers on corrosion. • Influence of the nanolayers interspacing and groove sizes on hardness and corrosion.

  16. Individual transferable quotas and conservation: a critical assessment

    Directory of Open Access Journals (Sweden)

    James Acheson

    2015-12-01

    Full Text Available Individual transferable quotas (ITQs have become a popular management tool for fisheries. They have been promoted in some quarters and seriously criticized in others because of their social and economic impacts. A more serious problem is that ITQs provide exclusive access to public resources presumably in return for some public benefit, namely conservation; however, in a high percentage of cases they do not conserve fish stocks. In this article, we focus on the reasons that ITQs do not conserve stocks. We point to a number of phenomena identified in the literature as affecting stocks of fish, including problems with total allowable catch (TAC, ecological hierarchy theory, r and K species, the Allee effect, scale and metapopulation structure, the need to have selective gear, and the continuation of roving bandit incentives. Despite their growing popularity with managers, ITQs do not solve any of these problems. We argue there may be better ways to manage. One possibility is what we call parametric management.

  17. Consequences of the quota requirement for energy efficiency. Can a Swedish quota obligation systems give less energy usage?; Konsekvenser av kvotplikt foer energieffektivisering. Kan ett svenskt kvotpliktssystem ge mindre energianvaendning?

    Energy Technology Data Exchange (ETDEWEB)

    Bjoerkroth, Sara; Bladh, Mats; Holmberg, Rurik; Lock, Anna; Naderi, Ronak; Widerstroem, Glenn

    2012-11-01

    The Agency has on behalf of the government investigated what the consequences would be of the introduction of a compulsory quota system in Sweden. Under the proposed new EU directive on energy efficiency, all Member States should introduce a compulsory quota system, where energy companies actively initiate measures for energy efficiency among end users. In Sweden, a quota obligation system of this kind would mean energy efficiency of about 3 TWh per year, which can be difficult to achieve. The Swedish Energy Agency suggests that if a compulsory quota system is introduced, the quota obligation should be placed on the network companies. If not, there is a risk of complications in the Swedish and Nordic electricity market. The Energy Markets Inspectorate consider that the quota obligation can not be on the network companies because of their function as regulated monopoly. The Swedish Energy Agency suggests that efficiency measures can be implemented in all sectors, including transport.

  18. Stratified charge rotary engine for general aviation

    Science.gov (United States)

    Mount, R. E.; Parente, A. M.; Hady, W. F.

    1986-01-01

    A development history, a current development status assessment, and a design feature and performance capabilities account are given for stratified-charge rotary engines applicable to aircraft propulsion. Such engines are capable of operating on Jet-A fuel with substantial cost savings, improved altitude capability, and lower fuel consumption by comparison with gas turbine powerplants. Attention is given to the current development program of a 400-hp engine scheduled for initial operations in early 1990. Stratified charge rotary engines are also applicable to ground power units, airborne APUs, shipboard generators, and vehicular engines.

  19. THE QUOTA RULE (AGE RESTRICTION IN THE THIRD LEAGUE IN TERMS OF ACTORS (DRAMATIS PERSONAE IN FOOTBALL

    Directory of Open Access Journals (Sweden)

    Mert Kerem Zelyurt

    2017-12-01

    Full Text Available In 2016 it was seen that the “quota rule” (age restriction which was put into practice in 2009 for the 3. League football teams in order to enable young players to have a better chance in squads and bring these players to the national teams have been changed because of not getting the desired results. In the study, the effects of 2009 quota rule which was established as a legal obligation to the football teams were examined in the extent of players, coaches, and the club managers (dramatis personae. The study was designed as “Semi-structured in-depth interview” (Qualitative Method method. According to “Theoretical Sampling Method” the sample of the study was formed through 6 players, 4 club managers and 5 coaches all of which are active in the third football league. The interviews recorded in February 2017 and May 2017, which vary from 6 minutes to 29 minutes in length according to the samples, were converted into text and categorized under 4 themes in findings section. The themes are: 1. being dropped out of squad 2. Problems relating the squads and the quality of the football 3.The problem of player training in the third league for the national team and transfer mobility to upper leagues 4. The fall in wages, the problem of becoming unemployed and being obliged to play in the amateur football league. As it can be concluded from the themes which frame the narrations by the samples including different experiences considering their status and roles in terms of quota rule practice; some outcomes during the period in which the rule had been practiced (particularly due to the version before the change were witnessed such as the deterioration in the quality of football, technical problems relating squads, the problem of vertical and horizontal professional mobility of the players and the fall in wages. In the last instance; it can be concluded that it is necessary to analyze legal sanctions relating a multivariate and intricate field such

  20. Risks prevention and fight against the pollutions. Publication of the practical guideline of the CO2 emissions quotas market

    International Nuclear Information System (INIS)

    2005-01-01

    Since January 2005 the directive on the emissions quotas exchange is applied in the 25 countries of the European Union. This text allocates emissions quotas to enterprises which generates many greenhouse gases. Hopeful these quotas, the European Union should decrease the emissions of 8% in 2010. This guide is devoted to the 1126 french sites concerned by the directive. It constitutes a reference for the quotas management and will help the enterprises to combine the fight against the climatic change with the economic competition. (A.L.B.)

  1. Nitrogen transformations in stratified aquatic microbial ecosystems

    DEFF Research Database (Denmark)

    Revsbech, N. P.; Risgaard-Petersen, N.; Schramm, A.

    2006-01-01

    Abstract  New analytical methods such as advanced molecular techniques and microsensors have resulted in new insights about how nitrogen transformations in stratified microbial systems such as sediments and biofilms are regulated at a µm-mm scale. A large and ever-expanding knowledge base about n...

  2. Impact of Carbon Quota Allocation Mechanism on Emissions Trading: An Agent-Based Simulation

    Directory of Open Access Journals (Sweden)

    Wei Jiang

    2016-08-01

    Full Text Available This paper establishes an agent-based simulation system of the carbon emissions trading in accordance with the complex feature of the trading process. This system analyzes the impact of the carbon quota allocation mechanism on emissions trading for three different aspects including the amount of emissions reduction, the economic effect on the emitters, and the emissions reduction cost. Based on the data of the carbon emissions of different industries in China, several simulations were made. The results indicate that the emissions trading policy can effectively reduce carbon emissions in a perfectly competitive market. Moreover, by comparing separate quota allocation mechanisms, we obtain the result that the scheme with a small extent quota decrease in a comprehensive allocation mechanism can minimize the unit carbon emission cost. Implementing this scheme can also achieve minimal effects of carbon emissions limitation on the economy on the basis that the environment is not destroyed. However, excessive quota decrease cannot promote the emitters to reduce emission. Taking into account that several developing countries have the dual task of limiting carbon emissions and developing the economy, it is necessary to adopt a comprehensive allocation mechanism of the carbon quota and increase the initial proportion of free allocation.

  3. Quota election system as a way of achieving descriptive and substantive representation of women in parliaments

    Directory of Open Access Journals (Sweden)

    Mršević Zorica

    2007-01-01

    Full Text Available In ten chapters of the text are analyzed issues of under representation of women in legislative bodies (descriptive representation matched with possibilities of their substantive representation. The substantive representation means contribution of women MPs in development and promotion of "women's politics" and politics of representing specific interest of women's part of population. In chapters under the titles, Underrepresented sex, Quota term, and Myths on quotas, are presented the main characteristics of the issues of women's under representation from political mainstream and decision-making bodies. There is also analyzed quota preferential electoral system as a solution. The gist of the text is comprised in the chapter Why Quotas where are presented the classical arguments for quotas as a specific measure of affirmative action. The way from increasing quantitative presence of women in legislative bodies to increasing the qualitative level of their activities in there is elaborated in the chapters Increasing numbers and achieving quality, Issues of women's political efficiency, Criteria of changes, and Inter parliamentarian activities of women. In the chapter Women's issues and women's perspectives is defined difference between these two aspects of women's MPs activities. Women's issues are those issues influencing directly women on physical or social way (e.g. breast cancer, reproductive rights, gender based discrimination, politics of child's care. The women's perspectives are specific women's interest and views of all other political issues.

  4. Impacts of Renewable Energy Quota System on China's Future Power Sector

    DEFF Research Database (Denmark)

    Xiong, Weiming; Zhang, Da; Mischke, Peggy

    2014-01-01

    As the biggest carbon emitting sector which produces 44% of current national carbon emission in China, the coal-dominated power sector has a tremendous potential for CO2 mitigation in the next two decades. Renewable energy quota system is currently discussed as a potential future policy instrument...... for the power sector, which requires certain fraction of renewable energy in total power generation for each province and grid zone. The quantitative studies on renewable energy quota for China are still very limited. Based on a least-cost and technology-rich power generation and transmission expansion model...... for China, this study examines the impacts of renewable energy quota system and carbon cap policy instruments on the future Chinese power sector. Various scenarios are examined toward 2030 and their future power generation mix, capacity installations and carbon emission are discussed. This study concludes...

  5. MC3D modelling of stratified explosion

    International Nuclear Information System (INIS)

    Picchi, S.; Berthoud, G.

    1999-01-01

    It is known that a steam explosion can occur in a stratified geometry and that the observed yields are lower than in the case of explosion in a premixture configuration. However, very few models are available to quantify the amount of melt which can be involved and the pressure peak that can be developed. In the stratified application of the MC3D code, mixing and fragmentation of the melt are explained by the growth of Kelvin Helmholtz instabilities due to the shear flow of the two phase coolant above the melt. Such a model is then used to recalculate the Frost-Ciccarelli tin-water experiment. Pressure peak, speed of propagation, bubble shape and erosion height are well reproduced as well as the influence of the inertial constraint (height of the water pool). (author)

  6. MC3D modelling of stratified explosion

    Energy Technology Data Exchange (ETDEWEB)

    Picchi, S.; Berthoud, G. [DTP/SMTH/LM2, CEA, 38 - Grenoble (France)

    1999-07-01

    It is known that a steam explosion can occur in a stratified geometry and that the observed yields are lower than in the case of explosion in a premixture configuration. However, very few models are available to quantify the amount of melt which can be involved and the pressure peak that can be developed. In the stratified application of the MC3D code, mixing and fragmentation of the melt are explained by the growth of Kelvin Helmholtz instabilities due to the shear flow of the two phase coolant above the melt. Such a model is then used to recalculate the Frost-Ciccarelli tin-water experiment. Pressure peak, speed of propagation, bubble shape and erosion height are well reproduced as well as the influence of the inertial constraint (height of the water pool). (author)

  7. Equipment for extracting and conveying stratified minerals

    Energy Technology Data Exchange (ETDEWEB)

    Blumenthal, G.; Kunzer, H.; Plaga, K.

    1991-08-14

    This invention relates to equipment for extracting stratified minerals and conveying the said minerals along the working face, comprising a trough shaped conveyor run assembled from lengths, a troughed extraction run in lengths matching the lengths of conveyor troughing, which is linked to the top edge of the working face side of the conveyor troughing with freedom to swivel vertically, and a positively guided chain carrying extraction tools and scrapers along the conveyor and extraction runs.

  8. Inviscid incompressible limits of strongly stratified fluids

    Czech Academy of Sciences Publication Activity Database

    Feireisl, Eduard; Jin, B.J.; Novotný, A.

    2014-01-01

    Roč. 89, 3-4 (2014), s. 307-329 ISSN 0921-7134 R&D Projects: GA ČR GA201/09/0917 Institutional support: RVO:67985840 Keywords : compressible Navier-Stokes system * anelastic approximation * stratified fluid Subject RIV: BA - General Mathematics Impact factor: 0.528, year: 2014 http://iospress.metapress.com/content/d71255745tl50125/?p=969b60ae82634854ab8bd25505ce1f71&pi=3

  9. Nitrogen transformations in stratified aquatic microbial ecosystems

    DEFF Research Database (Denmark)

    Revsbech, Niels Peter; Risgaard-Petersen, N.; Schramm, Andreas

    2006-01-01

    Abstract  New analytical methods such as advanced molecular techniques and microsensors have resulted in new insights about how nitrogen transformations in stratified microbial systems such as sediments and biofilms are regulated at a µm-mm scale. A large and ever-expanding knowledge base about n...... performing dissimilatory reduction of nitrate to ammonium have given new dimensions to the understanding of nitrogen cycling in nature, and the occurrence of these organisms and processes in stratified microbial communities will be described in detail.......Abstract  New analytical methods such as advanced molecular techniques and microsensors have resulted in new insights about how nitrogen transformations in stratified microbial systems such as sediments and biofilms are regulated at a µm-mm scale. A large and ever-expanding knowledge base about...... nitrogen fixation, nitrification, denitrification, and dissimilatory reduction of nitrate to ammonium, and about the microorganisms performing the processes, has been produced by use of these techniques. During the last decade the discovery of anammmox bacteria and migrating, nitrate accumulating bacteria...

  10. Large eddy simulation of stably stratified turbulence

    International Nuclear Information System (INIS)

    Shen Zhi; Zhang Zhaoshun; Cui Guixiang; Xu Chunxiao

    2011-01-01

    Stably stratified turbulence is a common phenomenon in atmosphere and ocean. In this paper the large eddy simulation is utilized for investigating homogeneous stably stratified turbulence numerically at Reynolds number Re = uL/v = 10 2 ∼10 3 and Froude number Fr = u/NL = 10 −2 ∼10 0 in which u is root mean square of velocity fluctuations, L is integral scale and N is Brunt-Vaïsälä frequency. Three sets of computation cases are designed with different initial conditions, namely isotropic turbulence, Taylor Green vortex and internal waves, to investigate the statistical properties from different origins. The computed horizontal and vertical energy spectra are consistent with observation in atmosphere and ocean when the composite parameter ReFr 2 is greater than O(1). It has also been found in this paper that the stratification turbulence can be developed under different initial velocity conditions and the internal wave energy is dominated in the developed stably stratified turbulence.

  11. Why quota trade should be restricted: The arguments behind the EU position on emissions trading

    International Nuclear Information System (INIS)

    Westskog, Hege

    2001-01-01

    In this paper I try to clarify the background and arguments behind the EU position on emissions trading in negotiating the Kyoto Protocol and their suggestions of how the supplementary cap in the Kyoto agreement can be operationalized. I discuss economic arguments for restricting quota trade with a focus on the market power issue, transaction costs, and ancillary benefits of reducing emissions of climate gases. I also address the problem of hot air as an important argument to restrict quota trade, and arguments for restrictions connected to technological innovation. Finally, I look into the ethical considerations of restrictions. (author)

  12. Are individual transferable quotas an adequate solution to overfishing and overcapacity? Evidence from Danish fisheries

    DEFF Research Database (Denmark)

    Merayo Garcia, Eugenia; Nielsen, Rasmus; Hoff, Ayoe

    2018-01-01

    Individual Transferable Quotas stand in large parts of the fisheries economic literature as the panacea that solves all problems of overfishing and overcapacity of world´s fisheries. However, they are also criticized by a number of authors based on their negative social effects. Individual...... in local fishing communities compared to the national average was found. The Danish experience proves that Individual Transferable Quotas can be an adequate solution with regards to overfishing and overcapacity with also positive effects on the environment due to reduced fuel consumption and fishing...

  13. Environmental taxes and quotas in the presence of distorting taxes in factor markets

    International Nuclear Information System (INIS)

    Parry, Ian W.H.

    1997-01-01

    Environmental quotas tend to compound the welfare cost of pre-existing tax distortions in the labor market. Under plausible parameters, this source of welfare loss can easily be large enough to outweigh the entire partial equilibrium welfare gain from the quota. Environmental taxes induce the same interaction effect, however they also raise government revenues. If the revenues are used to reduce distortionary taxes, then most of this interaction effect can be offset. Therefore, revenue-raising can be a necessary condition for environmental policies to increase welfare

  14. Why quota trade should be restricted: The arguments behind the EU position on emissions trading

    Energy Technology Data Exchange (ETDEWEB)

    Westskog, Hege

    2001-07-01

    In this paper I try to clarify the background and arguments behind the EU position on emissions trading in negotiating the Kyoto Protocol and their suggestions of how the supplementarity cap in the Kyoto agreement can be operationalized. I discuss economic arguments for restricting quota trade with a focus on the market power issue, transaction costs, and ancillary benefits of reducing emissions of climate gases. I also address the problem of hot air as an important argument to restrict quota trade, and arguments for restrictions connected to technological innovation. Finally, I look into the ethical considerations of restrictions. (author)

  15. Evidence from the 1920s U.S.Immigration Quota Acts

    DEFF Research Database (Denmark)

    Ager, Philipp; Hansen, Casper Worm

    2017-01-01

    in population growth in areas with larger pre-existing immigrant communities of affected nationalities. This effect was largely driven by the policy-restricted supply of immigrants from quota-affected nationalities and lower fertility of first- and second-generation immigrant women. In the more affected areas...... labor productivity growth in manufacturing declined substantially and native workers were pushed into lower-wage occupations. While native white workers faced sizable earnings losses, black workers benefited from the quota system and improved their relative economic status within the more affected areas....

  16. Quotas and women's substantive representation: Evidence from a content analysis of Ugandan plenary debates

    OpenAIRE

    Clayton, Amanda; Josefsson, Cecilia; Wang, Vibeke

    2017-01-01

    Despite the popularity of electoral gender quotas, the substantive impact of quotas on the plenary behavior of members of parliament (MPs) has yet to be thoroughly empirically explored, and in particular, there is a dearth of evidence from non-Western cases. Here we create a unique content analysis dataset from 14 years (1998–2011) of plenary debates, including the contents of more than 150,000 unique MP speeches recorded in some 40,000 pages of the Ugandan parliamentary Hansard to test how M...

  17. 76 FR 50285 - Fiscal Year 2012 Tariff-Rate Quota Allocations for Raw Cane Sugar, Refined and Specialty Sugar...

    Science.gov (United States)

    2011-08-12

    ... for Raw Cane Sugar, Refined and Specialty Sugar and Sugar-Containing Products AGENCY: Office of the... quantity of the tariff-rate quotas for imported raw cane sugar, refined and specialty sugar and sugar...), the United States maintains tariff-rate quotas (TRQs) for imports of raw cane sugar and refined sugar...

  18. 75 FR 39612 - Allocation of Second Additional Fiscal Year (FY) 2010 In-Quota Volume for Raw Cane Sugar

    Science.gov (United States)

    2010-07-09

    ...) 2010 In-Quota Volume for Raw Cane Sugar AGENCY: Office of the United States Trade Representative... the tariff-rate quota (TRQ) for imported raw cane sugar. DATES: Effective Date: July 9, 2010... cane and refined sugar. Section 404(d) (3) of the Uruguay Round Agreements Act (19 U.S.C. 3601(d)(3...

  19. 75 FR 60067 - Limitations of Duty- and Quota-Free Imports of Apparel Articles Assembled in Beneficiary Sub...

    Science.gov (United States)

    2010-09-29

    ... COMMITTEE FOR THE IMPLEMENTATION OF TEXTILE AGREEMENTS Limitations of Duty- and Quota-Free Imports... New 12-Month Cap on Duty- and Quota-Free Benefits. DATES: Effective Date: October 1, 2010. FOR FURTHER... 2004, Pub. L. 108-274; Division D, Title VI, section 6002 of the Tax Relief and Health Care Act of 2006...

  20. Analyse multi-échelle du comouvement entre les prix du quota carbone, du crédit carbone, et des produits énergétiques

    OpenAIRE

    Nsouadi, Clarda

    2016-01-01

    The purpose of this thesis is to contribute to the understanding of the carbon price quota structure, the analysis of its fluctuation, and the interactions that may exist between on the one hand the EU system of emission quota exchange (ETS) and the mechanism for clean development (CDM) and on the other hand between carbon quota market and the quota in the energy sector. For this study, we introduced the hypothesis of heterogeneity of agents' behavior on the carbon market where coexist multip...

  1. [Causes of emergency dizziness stratified by etiology].

    Science.gov (United States)

    Qiao, Wenying; Liu, Jianguo; Zeng, Hong; Liu, Yugeng; Jia, Weihua; Wang, Honghong; Liu, Bo; Tan, Jing; Li, Changqing

    2014-06-03

    To explore the causes of emergency dizziness stratified to improve the diagnostic efficiency. A total of 1 857 cases of dizziness at our emergency department were collected and their etiologies stratified by age and gender. The top three diagnoses were benign paroxysmal positional vertigo (BPPV, 31.7%), hypertension (24.0%) and posterior circulation ischemia (PCI, 20.5%). Stratified by age, the main causes of dizziness included BPPV (n = 6), migraine-associated vertigo (n = 2), unknown cause (n = 1) for the group of vertigo (14.5%) and neurosis (7.3%) for 18-44 years; BPPV (36.8%), hypertension (22.4%) and migraine-associated vertigo (11.2%) for 45-59 years; hypertension (30.8%), PCI (29.8%) and BPPV (22.9%) for 60-74 years; PCI (30.7%), hypertension (28.6%) and BPPV (25.5%) for 75-92 years. BPPV, migraine and neurosis were more common in females while hypertension and PCI predominated in males (all P hypertension, neurosis and migraine showed the following significant demographic features: BPPV, PCI, hypertension, neurosis and migraine may be the main causes of dizziness. BPPV should be considered initially when vertigo was triggered repeatedly by positional change, especially for young and middle-aged women. And the other common causes of dizziness were migraine-associated vertigo, neurosis and Meniere's disease.Hypertension should be screened firstly in middle-aged and elderly patients presenting mainly with head heaviness and stretching. In elders with dizziness, BPPV is second in constituent ratio to PCI and hypertension.In middle-aged and elderly patients with dizziness, psychological factors should be considered and diagnosis and treatment should be offered timely.

  2. White dwarf stars with chemically stratified atmospheres

    Science.gov (United States)

    Muchmore, D.

    1982-01-01

    Recent observations and theory suggest that some white dwarfs may have chemically stratified atmospheres - thin layers of hydrogen lying above helium-rich envelopes. Models of such atmospheres show that a discontinuous temperature inversion can occur at the boundary between the layers. Model spectra for layered atmospheres at 30,000 K and 50,000 K tend to have smaller decrements at 912 A, 504 A, and 228 A than uniform atmospheres would have. On the basis of their continuous extreme ultraviolet spectra, it is possible to distinguish observationally between uniform and layered atmospheres for hot white dwarfs.

  3. Stratified B-trees and versioning dictionaries

    OpenAIRE

    Twigg, Andy; Byde, Andrew; Milos, Grzegorz; Moreton, Tim; Wilkes, John; Wilkie, Tom

    2011-01-01

    A classic versioned data structure in storage and computer science is the copy-on-write (CoW) B-tree -- it underlies many of today's file systems and databases, including WAFL, ZFS, Btrfs and more. Unfortunately, it doesn't inherit the B-tree's optimality properties; it has poor space utilization, cannot offer fast updates, and relies on random IO to scale. Yet, nothing better has been developed since. We describe the `stratified B-tree', which beats all known semi-external memory versioned B...

  4. Large Scale Management of Physicists Personal Analysis Data Without Employing User and Group Quotas

    International Nuclear Information System (INIS)

    Norman, A.; Diesbug, M.; Gheith, M.; Illingworth, R.; Lyon, A.; Mengel, M.

    2015-01-01

    The ability of modern HEP experiments to acquire and process unprecedented amounts of data and simulation have lead to an explosion in the volume of information that individual scientists deal with on a daily basis. Explosion has resulted in a need for individuals to generate and keep large personal analysis data sets which represent the skimmed portions of official data collections, pertaining to their specific analysis. While a significant reduction in size compared to the original data, these personal analysis and simulation sets can be many terabytes or 10s of TB in size and consist of 10s of thousands of files. When this personal data is aggregated across the many physicists in a single analysis group or experiment it can represent data volumes on par or exceeding the official production samples which require special data handling techniques to deal with effectively.In this paper we explore the changes to the Fermilab computing infrastructure and computing models which have been developed to allow experimenters to effectively manage their personal analysis data and other data that falls outside of the typically centrally managed production chains. In particular we describe the models and tools that are being used to provide the modern neutrino experiments like NOvA with storage resources that are sufficient to meet their analysis needs, without imposing specific quotas on users or groups of users. We discuss the storage mechanisms and the caching algorithms that are being used as well as the toolkits are have been developed to allow the users to easily operate with terascale+ datasets. (paper)

  5. 78 FR 21584 - Atlantic Highly Migratory Species; 2013 Atlantic Bluefin Tuna Quota Specifications

    Science.gov (United States)

    2013-04-11

    ... and for 2012, inclusive of dead discards (ICCAT Recommendation 10-03--Supplemental Recommendation by... 858.4 mt, which is 185.2 mt less than the amount of quota (inclusive of dead discards) allowed under... locations will be physically accessible to people with disabilities. Requests for sign language...

  6. Looking back and moving forward: A closer look at the Dutch gender quota

    Directory of Open Access Journals (Sweden)

    Annika Galle

    2016-12-01

    Full Text Available The Dutch Civil Code stipulates that, for balanced gender representation, 30% of seats on the boards of large corporations should be occupied by women. If a company does not meet this requirement, the company is compelled to be transparent in its annual report by means of the ‘comply or explain’ principle. This article analyses the application of this rule through content analysis of the annual reports of 52 listed companies in 2012 and 49 in 2013. The article discusses whether this rule has the desired effect of creating transparency on the gender quota. The conclusion is that ‘the comply or explain’ mechanism is inadequate without further measures, including sanctions. For 2012, 21% of the companies researched made no mention in their annual report of the application of the gender quota. In 2013, 18% of the companies made no mention of it. The companies that did indicate that they did not meet the quota failed to provide the required transparency. The reasons cited for not meeting the quota are nothing more than clichéd phrases, lacking any specificity. If the Netherlands wants to achieve the European and Dutch targets with the aid of the ’comply or explain’ mechanism, the government will have to introduce additional mechanisms, including sanctions - or, alternatively, steer an entirely different course.

  7. 78 FR 30865 - Proposed Information Collection; Comment Request; Tilefish Individual Fishing Quota Program

    Science.gov (United States)

    2013-05-23

    ... Northeastern U.S. EEZ. II. Method of Collection The IFQ Allocation permit application, IFQ holder cap form, and... before July 22, 2013. ADDRESSES: Direct all written comments to Jennifer Jessup, Departmental Paperwork... applications to ensure that IFQ allocation holders are provided a statement of their annual catch quota, and...

  8. 77 FR 16209 - Proposed Information Collection; Comment Request; Tilefish Individual Fishing Quota Program

    Science.gov (United States)

    2012-03-20

    ... Northeastern U.S. EEZ. II. Method of Collection The IFQ Allocation permit application, IFQ ownership cap form... before May 21, 2012. ADDRESSES: Direct all written comments to Jennifer Jessup, Departmental Paperwork... applications to ensure that IFQ allocation owners are provided a statement of their annual catch quota, and for...

  9. 77 FR 16210 - Proposed Information Collection; Comment Request; Tilefish Individual Fishing Quota Program

    Science.gov (United States)

    2012-03-20

    ... Northeastern U.S. EEZ. II. Method of Collection The IFQ Allocation permit application, IFQ ownership cap form... before May 21, 2012. ADDRESSES: Direct all written comments to Jennifer Jessup, Departmental Paperwork... applications to ensure that IFQ allocation owners are provided a statement of their annual catch quota, and for...

  10. 75 FR 5760 - Proposed Information Collection; Comment Request; Western Alaska Community Development Quota Program

    Science.gov (United States)

    2010-02-04

    ... before April 5, 2010. ADDRESSES: Direct all written comments to Diana Hynek, Departmental Paperwork... and diversified local economies in western Alaska. CDQ and prohibited species quota (PSQ) allocations... collection. II. Method of Collection Respondents have a choice of either electronic or paper forms. Methods...

  11. 77 FR 44161 - Atlantic Highly Migratory Species; 2012 Atlantic Bluefin Tuna Quota Specifications

    Science.gov (United States)

    2012-07-27

    ... order to stay within the ICCAT-recommended U.S. quota, close directed BFT fisheries in the event that... 5, 2011) to consider information about the Deepwater Horizon/BP oil spill and alleged illegal... and use the best available science on the effects of the Deepwater Horizon/BP oil spill and the...

  12. 76 FR 39019 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Quotas and Atlantic Tuna Fisheries...

    Science.gov (United States)

    2011-07-05

    ... for the more selective, directed fishing categories, and be a de facto reallocation of quota shares... of post-release mortality received substantial attention at the 2010 ICCAT meeting and NMFS... would not help for giant BFT that may not fit in the hold. NMFS should allow the tail to be cut but...

  13. [Work quota setting and man-hour productivity estimation in pathologists].

    Science.gov (United States)

    Svistunov, V V; Makarov, S V; Makarova, A E

    The paper considers the development and current state of the regulation of work quota setting and remuneration in pathologists. Reasoning from the current staff standards for morbid anatomy departments (units), the authors present a method to calculate the load of pathologists. The essence of the proposed method is demonstrated using a specific example.

  14. 75 FR 82295 - Fisheries of the Northeastern United States; Atlantic Bluefish Fishery; Quota Transfer

    Science.gov (United States)

    2010-12-30

    .... 100204079-0199-02] RIN 0648-XA084 Fisheries of the Northeastern United States; Atlantic Bluefish Fishery... the Commonwealth of Virginia is transferring commercial bluefish quota to the State of North Carolina... INFORMATION: Regulations governing the Atlantic bluefish fishery are found at 50 CFR part 648. The regulations...

  15. 77 FR 58051 - Fisheries of the Northeastern United States; Bluefish Fishery; Commercial Quota Harvested for the...

    Science.gov (United States)

    2012-09-19

    .... 120201086-2418-02] RIN 0648-XC236 Fisheries of the Northeastern United States; Bluefish Fishery; Commercial...: NMFS announces that the 2012 bluefish commercial quota allocated to the Commonwealth of Massachusetts has been harvested. Vessels issued a commercial Federal fisheries permit for the bluefish fishery may...

  16. 76 FR 61472 - Revised Fiscal Year 2011 Tariff-Rate Quota Allocations for Refined Sugar

    Science.gov (United States)

    2011-10-04

    ... any agricultural product among supplying countries or customs areas. The President delegated this... Agriculture established the FY 2011 (October 1, 2010--September 30, 2011) refined sugar TRQ at an aggregate... 35,300 MTRV. The remaining 111,078 MTRV of the increased in-quota quantity may be supplied by any...

  17. Soil mixing of stratified contaminated sands.

    Science.gov (United States)

    Al-Tabba, A; Ayotamuno, M J; Martin, R J

    2000-02-01

    Validation of soil mixing for the treatment of contaminated ground is needed in a wide range of site conditions to widen the application of the technology and to understand the mechanisms involved. Since very limited work has been carried out in heterogeneous ground conditions, this paper investigates the effectiveness of soil mixing in stratified sands using laboratory-scale augers. This enabled a low cost investigation of factors such as grout type and form, auger design, installation procedure, mixing mode, curing period, thickness of soil layers and natural moisture content on the unconfined compressive strength, leachability and leachate pH of the soil-grout mixes. The results showed that the auger design plays a very important part in the mixing process in heterogeneous sands. The variability of the properties measured in the stratified soils and the measurable variations caused by the various factors considered, highlighted the importance of duplicating appropriate in situ conditions, the usefulness of laboratory-scale modelling of in situ conditions and the importance of modelling soil and contaminant heterogeneities at the treatability study stage.

  18. Stratified coastal ocean interactions with tropical cyclones

    Science.gov (United States)

    Glenn, S. M.; Miles, T. N.; Seroka, G. N.; Xu, Y.; Forney, R. K.; Yu, F.; Roarty, H.; Schofield, O.; Kohut, J.

    2016-01-01

    Hurricane-intensity forecast improvements currently lag the progress achieved for hurricane tracks. Integrated ocean observations and simulations during hurricane Irene (2011) reveal that the wind-forced two-layer circulation of the stratified coastal ocean, and resultant shear-induced mixing, led to significant and rapid ahead-of-eye-centre cooling (at least 6 °C and up to 11 °C) over a wide swath of the continental shelf. Atmospheric simulations establish this cooling as the missing contribution required to reproduce Irene's accelerated intensity reduction. Historical buoys from 1985 to 2015 show that ahead-of-eye-centre cooling occurred beneath all 11 tropical cyclones that traversed the Mid-Atlantic Bight continental shelf during stratified summer conditions. A Yellow Sea buoy similarly revealed significant and rapid ahead-of-eye-centre cooling during Typhoon Muifa (2011). These findings establish that including realistic coastal baroclinic processes in forecasts of storm intensity and impacts will be increasingly critical to mid-latitude population centres as sea levels rise and tropical cyclone maximum intensities migrate poleward. PMID:26953963

  19. Stratified Simulations of Collisionless Accretion Disks

    Energy Technology Data Exchange (ETDEWEB)

    Hirabayashi, Kota; Hoshino, Masahiro, E-mail: hirabayashi-k@eps.s.u-tokyo.ac.jp [Department of Earth and Planetary Science, The University of Tokyo, Tokyo, 113-0033 (Japan)

    2017-06-10

    This paper presents a series of stratified-shearing-box simulations of collisionless accretion disks in the recently developed framework of kinetic magnetohydrodynamics (MHD), which can handle finite non-gyrotropy of a pressure tensor. Although a fully kinetic simulation predicted a more efficient angular-momentum transport in collisionless disks than in the standard MHD regime, the enhanced transport has not been observed in past kinetic-MHD approaches to gyrotropic pressure anisotropy. For the purpose of investigating this missing link between the fully kinetic and MHD treatments, this paper explores the role of non-gyrotropic pressure and makes the first attempt to incorporate certain collisionless effects into disk-scale, stratified disk simulations. When the timescale of gyrotropization was longer than, or comparable to, the disk-rotation frequency of the orbit, we found that the finite non-gyrotropy selectively remaining in the vicinity of current sheets contributes to suppressing magnetic reconnection in the shearing-box system. This leads to increases both in the saturated amplitude of the MHD turbulence driven by magnetorotational instabilities and in the resultant efficiency of angular-momentum transport. Our results seem to favor the fast advection of magnetic fields toward the rotation axis of a central object, which is required to launch an ultra-relativistic jet from a black hole accretion system in, for example, a magnetically arrested disk state.

  20. Distinguishing values from science in decision making: Setting harvest quotas for mountain lions in Montana

    Science.gov (United States)

    Mitchell, Michael S.; Cooley, Hilary; Gude, Justin A.; Kolbe, Jay; Nowak, J. Joshua; Proffitt, Kelly M.; Sells, Sarah N.; Thompson, Mike

    2018-01-01

    The relative roles of science and human values can be difficult to distinguish when informal processes are used to make complex and contentious decisions in wildlife management. Structured Decision Making (SDM) offers a formal process for making such decisions, where scientific results and concepts can be disentangled from the values of differing stakeholders. We used SDM to formally integrate science and human values for a citizen working group of ungulate hunting advocates, lion hunting advocates, and outfitters convened to address the contentious allocation of harvest quotas for mountain lions (Puma concolor) in west‐central Montana, USA, during 2014. A science team consisting of mountain lion biologists and population ecologists convened to support the working group. The science team used integrated population models that incorporated 4 estimates of mountain lion density to estimate population trajectories for 5 alternative harvest quotas developed by the working group. Results of the modeling predicted that effects of each harvest quota were consistent across the 4 density estimates; harvest quotas affected predicted population trajectories for 5 years after implementation but differences were not strong. Based on these results, the focus of the working group changed to differences in values among stakeholders that were the true impediment to allocating harvest quotas. By distinguishing roles of science and human values in this process, the working group was able to collaboratively recommend a compromise solution. This solution differed little from the status quo that had been the focus of debate, but the SDM process produced understanding and buy‐in among stakeholders involved, reducing disagreements, misunderstanding, and unproductive arguments founded on informal application of scientific data and concepts. Whereas investments involved in conducting SDM may be unnecessary for many decisions in wildlife management, the investment may be beneficial for

  1. Design-based Sample and Probability Law-Assumed Sample: Their Role in Scientific Investigation.

    Science.gov (United States)

    Ojeda, Mario Miguel; Sahai, Hardeo

    2002-01-01

    Discusses some key statistical concepts in probabilistic and non-probabilistic sampling to provide an overview for understanding the inference process. Suggests a statistical model constituting the basis of statistical inference and provides a brief review of the finite population descriptive inference and a quota sampling inferential theory.…

  2. Refugee Quota Trading within the Context of EU-ENP Cooperation: Rational, Bounded Rational and Ethical Critiques

    Directory of Open Access Journals (Sweden)

    Mollie Gerver

    2013-02-01

    Full Text Available In 1997 Peter Schuck proposed a ‘refugee quota trading’ mechanism, whereby countries voluntarily form a union, each country accepting a quota of refugees and able to buy and sell the quota to other states within and even outside of the union. Today, the EU arguably has a de facto cash transfer mechanism both within the EU and between the EU and European Neighbourhood Policy countries. This article explores the question of refugee quota trading, explaining why current EU policy fails to increase refugee protection. Throughout the critique, states are treated either as rational actors or actors with present-preference bias, the latter largely ignored in current discussions on international refugee ‘burden sharing’. In addition, the ethics of refugee quota trading is presented using arguments distinct from that of Anker et al. (1998 who argue that refugee quota trading creates a ‘commodification’ of refugees. One could argue that refugees’ protection is being commodified, not refugees themselves. However, when states are provided funds not to deport refugees, this can be a type of reward for not taking an action that states ought to follow regardless of the reward. Just as there are non-utilitarian reasons not to rely on rewards alone for lowering the crime rates for heinous crimes within states, there may be non-utilitarian arguments against refugee quota trading.

  3. Health-related quality of life predictors during medical residency in a random, stratified sample of residents Preditores de qualidade de vida relacionada à saúde durante a residência médica em uma amostra randomizada e estratificada de médicos residentes

    Directory of Open Access Journals (Sweden)

    Paula Costa Mosca Macedo

    2009-06-01

    Full Text Available OBJECTIVE: To evaluate the quality of life during the first three years of training and identify its association with sociodemographicoccupational characteristics, leisure time and health habits. METHOD: A cross-sectional study with a random sample of 128 residents stratified by year of training was conducted. The Medical Outcome Study -short form 36 was administered. Mann-Whitney tests were carried out to compare percentile distributions of the eight quality of life domains, according to sociodemographic variables, and a multiple linear regression analysis was performed, followed by a validity checking for the resulting models. RESULTS: The physical component presented higher quality of life medians than the mental component. Comparisons between the three years showed that in almost all domains the quality of life scores of the second year residents were higher than the first year residents (p OBJETIVO: Avaliar a qualidade de vida do médico residente durante os três anos do treinamento e identificar sua associação com as características sociodemográficas-ocupacionais, tempo de lazer e hábitos de saúde. MÉTODO: Foi realizado um estudo transversal com amostra randomizada de 128 residentes, estratificada por ano de residência. O Medical Outcome Study-Short Form 36 foi aplicado; as distribuições percentis dos domínios de qualidade de vida de acordo com variáveis sociodemográficas foram analisadas pelo teste de Mann-Whitney e regressão linear múltipla, bem como estudo de validação pós-regressão. RESULTADOS: O componente físico da qualidade de vida apresentou medianas mais altas do que o mental. Comparações entre os três anos mostraram que quase todos os domínios de qualidade de vida tiveram escores maiores no segundo do que no primeiro ano (p < 0,01; em relação ao componente mental observamos maiores escores no terceiro ano do que nos demais (p < 0,01. Preditores de maior qualidade de vida foram: estar no segundo ou

  4. Ecosystem metabolism in a stratified lake

    DEFF Research Database (Denmark)

    Stæhr, Peter Anton; Christensen, Jesper Philip Aagaard; Batt, Ryan D.

    2012-01-01

    , differences were not significant. During stratification, daily variability in epilimnetic DO was dominated by metabolism (46%) and air-water gas exchange (44%). Fluxes related to mixed-layer deepening dominated in meta- and hypolimnic waters (49% and 64%), while eddy diffusion (1% and 14%) was less important....... Although air-water gas exchange rates differed among the three formulations of gas-transfer velocity, this had no significant effect on metabolic rates....... that integrates rates across the entire depth profile and includes DO exchange between depth layers driven by mixed-layer deepening and eddy diffusivity. During full mixing, NEP was close to zero throughout the water column, and GPP and R were reduced 2-10 times compared to stratified periods. When present...

  5. Stratified growth in Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Werner, E.; Roe, F.; Bugnicourt, A.

    2004-01-01

    In this study, stratified patterns of protein synthesis and growth were demonstrated in Pseudomonas aeruginosa biofilms. Spatial patterns of protein synthetic activity inside biofilms were characterized by the use of two green fluorescent protein (GFP) reporter gene constructs. One construct...... synthesis was restricted to a narrow band in the part of the biofilm adjacent to the source of oxygen. The zone of active GFP expression was approximately 60 Am wide in colony biofilms and 30 Am wide in flow cell biofilms. The region of the biofilm in which cells were capable of elongation was mapped...... by treating colony biofilms with carbenicillin, which blocks cell division, and then measuring individual cell lengths by transmission electron microscopy. Cell elongation was localized at the air interface of the biofilm. The heterogeneous anabolic patterns measured inside these biofilms were likely a result...

  6. Thermal instability in a stratified plasma

    International Nuclear Information System (INIS)

    Hermanns, D.F.M.; Priest, E.R.

    1989-01-01

    The thermal instability mechansism has been studied in connection to observed coronal features, like, e.g. prominences or cool cores in loops. Although these features show a lot of structure, most studies concern the thermal instability in an uniform medium. In this paper, we investigate the thermal instability and the interaction between thermal modes and the slow magneto-acoustic subspectrum for a stratified plasma slab. We fomulate the relevant system of equations and give some straightforward properties of the linear spectrum of a non-uniform plasma slab, i.e. the existence of continuous parts in the spectrum. We present a numerical scheme with which we can investigate the linear spectrum for equilibrium states with stratification. The slow and thermal subspectra of a crude coronal model are given as a preliminary result. (author). 6 refs.; 1 fig

  7. Stratified charge rotary engine combustion studies

    Science.gov (United States)

    Shock, H.; Hamady, F.; Somerton, C.; Stuecken, T.; Chouinard, E.; Rachal, T.; Kosterman, J.; Lambeth, M.; Olbrich, C.

    1989-07-01

    Analytical and experimental studies of the combustion process in a stratified charge rotary engine (SCRE) continue to be the subject of active research in recent years. Specifically to meet the demand for more sophisticated products, a detailed understanding of the engine system of interest is warranted. With this in mind the objective of this work is to develop an understanding of the controlling factors that affect the SCRE combustion process so that an efficient power dense rotary engine can be designed. The influence of the induction-exhaust systems and the rotor geometry are believed to have a significant effect on combustion chamber flow characteristics. In this report, emphasis is centered on Laser Doppler Velocimetry (LDV) measurements and on qualitative flow visualizations in the combustion chamber of the motored rotary engine assembly. This will provide a basic understanding of the flow process in the RCE and serve as a data base for verification of numerical simulations. Understanding fuel injection provisions is also important to the successful operation of the stratified charge rotary engine. Toward this end, flow visualizations depicting the development of high speed, high pressure fuel jets are described. Friction is an important consideration in an engine from the standpoint of lost work, durability and reliability. MSU Engine Research Laboratory efforts in accessing the frictional losses associated with the rotary engine are described. This includes work which describes losses in bearing, seal and auxillary components. Finally, a computer controlled mapping system under development is described. This system can be used to map shapes such as combustion chamber, intake manifolds or turbine blades accurately.

  8. Sampling in Developmental Science: Situations, Shortcomings, Solutions, and Standards

    OpenAIRE

    Bornstein, Marc H.; Jager, Justin; Putnick, Diane L.

    2013-01-01

    Sampling is a key feature of every study in developmental science. Although sampling has far-reaching implications, too little attention is paid to sampling. Here, we describe, discuss, and evaluate four prominent sampling strategies in developmental science: population-based probability sampling, convenience sampling, quota sampling, and homogeneous sampling. We then judge these sampling strategies by five criteria: whether they yield representative and generalizable estimates of a study’s t...

  9. The optimism trap: Migrants' educational choices in stratified education systems.

    Science.gov (United States)

    Tjaden, Jasper Dag; Hunkler, Christian

    2017-09-01

    Immigrant children's ambitious educational choices have often been linked to their families' high level of optimism and motivation for upward mobility. However, previous research has mostly neglected alternative explanations such as information asymmetries or anticipated discrimination. Moreover, immigrant children's higher dropout rates at the higher secondary and university level suggest that low performing migrant students could have benefitted more from pursuing less ambitious tracks, especially in countries that offer viable vocational alternatives. We examine ethnic minority's educational choices using a sample of academically low performing, lower secondary school students in Germany's highly stratified education system. We find that their families' optimism diverts migrant students from viable vocational alternatives. Information asymmetries and anticipated discrimination do not explain their high educational ambitions. While our findings further support the immigrant optimism hypothesis, we discuss how its effect may have different implications depending on the education system. Copyright © 2017. Published by Elsevier Inc.

  10. The effect of surfactant on stratified and stratifying gas-liquid flows

    Science.gov (United States)

    Heiles, Baptiste; Zadrazil, Ivan; Matar, Omar

    2013-11-01

    We consider the dynamics of a stratified/stratifying gas-liquid flow in horizontal tubes. This flow regime is characterised by the thin liquid films that drain under gravity along the pipe interior, forming a pool at the bottom of the tube, and the formation of large-amplitude waves at the gas-liquid interface. This regime is also accompanied by the detachment of droplets from the interface and their entrainment into the gas phase. We carry out an experimental study involving axial- and radial-view photography of the flow, in the presence and absence of surfactant. We show that the effect of surfactant is to reduce significantly the average diameter of the entrained droplets, through a tip-streaming mechanism. We also highlight the influence of surfactant on the characteristics of the interfacial waves, and the pressure gradient that drives the flow. EPSRC Programme Grant EP/K003976/1.

  11. Environmental policy in Norway: emission quotas to the processing industries, taxation of the oil companies

    International Nuclear Information System (INIS)

    Tjernshaugen, Andreas

    2002-01-01

    In a white paper on the climate policy, the Norwegian Government proposes a variety of political instruments. In the years 2005 to 2007, the Government will give priority to a quota system for the industrial sectors that are currently exempt from the CO 2 tax. At the same time, the tax on oil- and gas extraction and on traffic will be continued. In addition, a series of measures are evaluated against specific emission sources such as waste management and oil heating. For the years 2008 to 2012, which is the period of commitment under the Kyoto protocol, the CO 2 will be replaced by a broad quota system that will apply to all sources that can be technically included

  12. [The law of quotas for people with disabilities in Brazilian companies: the impact and possible alternatives].

    Science.gov (United States)

    Zanitelli, Leandro Martins

    2013-07-01

    This paper consists of a theoretical analysis of the impact of the Brazilian law establishing quotas for people with disabilities in companies with one hundred or more employees, as well as the possible impact of some alternative legal measures: incentives (fiscal incentives and tradable rights) and information disclosure policies. The analysis is based on work regarding the efficacy of legal norms in general, and particularly the literature concerning the cost and cognitive effects of those norms. Given its exclusively theoretical character, the paper does not affirm the superiority of any regulatory strategy over the current law, but draws attention to the likely reasons for the failure of the quota system and for the potential and inconveniences of its proposed alternatives.

  13. Resource control in ATLAS distributed data management: Rucio Accounting and Quotas

    CERN Document Server

    Barisits, Martin-Stefan; The ATLAS collaboration

    2015-01-01

    The ATLAS Distributed Data Management system stores more than 160PB of physics data across more than 130 sites globally. Rucio, the next-generation data management system of ATLAS has been introduced to cope with the anticipated workload of the coming decade. The previous data management system DQ2 pursued a rather simplistic approach for resource management, but with the increased data volume and more dynamic handling of data workflows required by the experiment, a more elaborate approach to this issue is needed. This document describes how resources, like storage, accounts and replication requests, are accounted in Rucio. Especially the measurement of used logical storage space is fundamentally different in Rucio than it’s predecessor DQ2. We introduce a new concept of declaring quota policies (limits) for accounts in Rucio. This new quota concept is based on accounts and RSE (Rucio storage element) expressions, which allows the definition of account limits in a dynamic way. This concept enables the opera...

  14. Effect of production quotas on economic and environmental values of growth rate and feed efficiency in sea cage fish farming.

    Science.gov (United States)

    Besson, M; de Boer, I J M; Vandeputte, M; van Arendonk, J A M; Quillet, E; Komen, H; Aubin, J

    2017-01-01

    In sea cage fish farming, production quotas aim to constrain the impact of fish farming on the surrounding ecosystem. It is unknown how these quotas affect economic profitability and environmental impact of genetic improvement. We combined bioeconomic modelling with life cycle assessment (LCA) to calculate the economic (EV) and environmental (ENV) values of thermal growth coefficient (TGC) and feed conversion ratio (FCR) of sea bass reared in sea cages, given four types of quota commonly used in Europe: annual production (Qprod), annual feed distributed (Qannual_feed), standing stock (Qstock), and daily feed distributed (Qdaily_feed). ENV were calculated for LCA impact categories climate change, eutrophication and acidification. ENV were expressed per ton of fish produced per year (ENV(fish)) and per farm per year (ENV(farm)). Results show that irrespective of quota used, EV of FCR as well as ENV(fish) and ENV(farm) were always positive, meaning that improving FCR increased profit and decreased environmental impacts. However, the EV and the ENV(fish) of TGC were positive only when quota was Qstock or Qdaily_feed. Moreover, the ENV(farm) of TGC was negative in Qstock and Qdaily_feed quotas, meaning that improving TGC increased the environmental impact of the farm. We conclude that Qstock quota and Qdaily_feed quota are economically favorable to a genetic improvement of TGC, a major trait for farmers. However, improving TGC increases the environmental impact of the farm. Improving FCR represents a good opportunity to balance out this increase but more information on its genetic background is needed to develop breeding programs improving FCR.

  15. Effect of production quotas on economic and environmental values of growth rate and feed efficiency in sea cage fish farming.

    Directory of Open Access Journals (Sweden)

    M Besson

    Full Text Available In sea cage fish farming, production quotas aim to constrain the impact of fish farming on the surrounding ecosystem. It is unknown how these quotas affect economic profitability and environmental impact of genetic improvement. We combined bioeconomic modelling with life cycle assessment (LCA to calculate the economic (EV and environmental (ENV values of thermal growth coefficient (TGC and feed conversion ratio (FCR of sea bass reared in sea cages, given four types of quota commonly used in Europe: annual production (Qprod, annual feed distributed (Qannual_feed, standing stock (Qstock, and daily feed distributed (Qdaily_feed. ENV were calculated for LCA impact categories climate change, eutrophication and acidification. ENV were expressed per ton of fish produced per year (ENV(fish and per farm per year (ENV(farm. Results show that irrespective of quota used, EV of FCR as well as ENV(fish and ENV(farm were always positive, meaning that improving FCR increased profit and decreased environmental impacts. However, the EV and the ENV(fish of TGC were positive only when quota was Qstock or Qdaily_feed. Moreover, the ENV(farm of TGC was negative in Qstock and Qdaily_feed quotas, meaning that improving TGC increased the environmental impact of the farm. We conclude that Qstock quota and Qdaily_feed quota are economically favorable to a genetic improvement of TGC, a major trait for farmers. However, improving TGC increases the environmental impact of the farm. Improving FCR represents a good opportunity to balance out this increase but more information on its genetic background is needed to develop breeding programs improving FCR.

  16. 77 FR 15712 - Atlantic Highly Migratory Species; 2012 Atlantic Bluefin Tuna Quota Specifications

    Science.gov (United States)

    2012-03-16

    ... annual meeting, ICCAT recommended a TAC of 1,750 mt annually for 2011 and for 2012, inclusive of dead... 868.6 mt, which is 175 mt less than the amount of quota (inclusive of dead discards) allowed under... 182.0 SUBQUOTAS: SUBQUOTAS: School 94.9 School 94.9 Reserve 17.6 Reserve 17.6 North 36.5 North 36.5...

  17. Protecting Marine Biodiversity: A Comparison of Individual Habitat Quotas (IHQs) and Marine Protected Areas

    OpenAIRE

    Kurt Schnier; Dan Holland

    2005-01-01

    Fisheries managers in the United States are required to identify and mitigate the adverse impacts of fishing activity on essential fish habitat (EFH). There are additional concerns that the viability of noncommercial species, animals that are habitat dependent and/or are themselves constituents of fishery habitat may still be threatened. We consider a cap-and-trade system for habitat conservation, individual habitat quotas for fisheries, to achieve habitat conservation and species protection ...

  18. Improved patient selection by stratified surgical intervention

    DEFF Research Database (Denmark)

    Wang, Miao; Bünger, Cody E; Li, Haisheng

    2015-01-01

    BACKGROUND CONTEXT: Choosing the best surgical treatment for patients with spinal metastases remains a significant challenge for spine surgeons. There is currently no gold standard for surgical treatments. The Aarhus Spinal Metastases Algorithm (ASMA) was established to help surgeons choose...... the most appropriate surgical intervention for patients with spinal metastases. PURPOSE: The purpose of this study was to evaluate the clinical outcome of stratified surgical interventions based on the ASMA, which combines life expectancy and the anatomical classification of patients with spinal metastases...... survival times in the five surgical groups determined by the ASMA were 2.1 (TS 0-4, TC 1-7), 5.1 (TS 5-8, TC 1-7), 12.1 (TS 9-11, TC 1-7 or TS 12-15, TC 7), 26.0 (TS 12-15, TC 4-6), and 36.0 (TS 12-15, TC 1-3) months. The 30-day mortality rate was 7.5%. Postoperative neurological function was maintained...

  19. Experimental study of unsteady thermally stratified flow

    International Nuclear Information System (INIS)

    Lee, Sang Jun; Chung, Myung Kyoon

    1985-01-01

    Unsteady thermally stratified flow caused by two-dimensional surface discharge of warm water into a oblong channel was investigated. Experimental study was focused on the rapidly developing thermal diffusion at small Richardson number. The basic objectives were to study the interfacial mixing between a flowing layer of warm water and an underlying body of cold water and to accumulate experimental data to test computational turbulence models. Mean velocity field measurements were carried out by using NMR-CT(Nuclear Magnetic Resonance-Computerized Tomography). It detects quantitative flow image of any desired section in any direction of flow in short time. Results show that at small Richardson number warm layer rapidly penetrates into the cold layer because of strong turbulent mixing and instability between the two layers. It is found that the transfer of heat across the interface is more vigorous than that of momentum. It is also proved that the NMR-CT technique is a very valuable tool to measure unsteady three dimensional flow field. (Author)

  20. Turbulent fluxes in stably stratified boundary layers

    International Nuclear Information System (INIS)

    L'vov, Victor S; Procaccia, Itamar; Rudenko, Oleksii

    2008-01-01

    We present here an extended version of an invited talk we gave at the international conference 'Turbulent Mixing and Beyond'. The dynamical and statistical description of stably stratified turbulent boundary layers with the important example of the stable atmospheric boundary layer in mind is addressed. Traditional approaches to this problem, based on the profiles of mean quantities, velocity second-order correlations and dimensional estimates of the turbulent thermal flux, run into a well-known difficulty, predicting the suppression of turbulence at a small critical value of the Richardson number, in contradiction to observations. Phenomenological attempts to overcome this problem suffer from various theoretical inconsistencies. Here, we present an approach taking into full account all the second-order statistics, which allows us to respect the conservation of total mechanical energy. The analysis culminates in an analytic solution of the profiles of all mean quantities and all second-order correlations, removing the unphysical predictions of previous theories. We propose that the approach taken here is sufficient to describe the lower parts of the atmospheric boundary layer, as long as the Richardson number does not exceed an order of unity. For much higher Richardson numbers, the physics may change qualitatively, requiring careful consideration of the potential Kelvin-Helmoholtz waves and their interaction with the vortical turbulence.

  1. The Quota-Based Compensation Plan in Fashion Retailing Industry under Asymmetric Information

    Directory of Open Access Journals (Sweden)

    Mingzhu Yu

    2014-01-01

    Full Text Available We study a compensation plan problem in the fashion retailing industry, which involves a risk-neutral fashion retailer and a risk-neutral salesperson, in a two-stage game framework with asymmetric information. In the first stage, the fashion retailer provides a menu of compensation plans to the salesperson who decides which plan to sign based on his superior market demand information. Confronted with the asymmetric demand information, the fashion retailer could observe market information from the salesperson's response by designing a menu of compensation plans rather than a single one to the salesperson. In the second stage, the fashion retailer then makes production decision and the salesperson determines his selling effort. We consider both adverse selection and moral hazard. We adopt the quota-based plan to derive the fashion retailer’s optimal compensation plan design and the salesperson's best response. We emphasize the impact of the quota level on the system outcomes. The results reveal that a higher quota level is disadvantageous to the fashion retailer but advantageous to the salespersons.

  2. Analysis of Turbulent Combustion in Simplified Stratified Charge Conditions

    Science.gov (United States)

    Moriyoshi, Yasuo; Morikawa, Hideaki; Komatsu, Eiji

    The stratified charge combustion system has been widely studied due to the significant potentials for low fuel consumption rate and low exhaust gas emissions. The fuel-air mixture formation process in a direct-injection stratified charge engine is influenced by various parameters, such as atomization, evaporation, and in-cylinder gas motion at high temperature and high pressure conditions. It is difficult to observe the in-cylinder phenomena in such conditions and also challenging to analyze the following stratified charge combustion. Therefore, the combustion phenomena in simplified stratified charge conditions aiming to analyze the fundamental stratified charge combustion are examined. That is, an experimental apparatus which can control the mixture distribution and the gas motion at ignition timing was developed, and the effects of turbulence intensity, mixture concentration distribution, and mixture composition on stratified charge combustion were examined. As a result, the effects of fuel, charge stratification, and turbulence on combustion characteristics were clarified.

  3. Modelling of vapour explosion in stratified geometrie

    International Nuclear Information System (INIS)

    Picchi, St.

    1999-01-01

    When a hot liquid comes into contact with a colder volatile liquid, one can obtain in some conditions an explosive vaporization, told vapour explosion, whose consequences can be important on neighbouring structures. This explosion needs the intimate mixing and the fine fragmentation between the two liquids. In a stratified vapour explosion, these two liquids are initially superposed and separated by a vapor film. A triggering of the explosion can induce a propagation of this along the film. A study of experimental results and existent models has allowed to retain the following main points: - the explosion propagation is due to a pressure wave propagating through the medium; - the mixing is due to the development of Kelvin-Helmholtz instabilities induced by the shear velocity between the two liquids behind the pressure wave. The presence of the vapour in the volatile liquid explains experimental propagation velocity and the velocity difference between the two fluids at the pressure wave crossing. A first model has been proposed by Brayer in 1994 in order to describe the fragmentation and the mixing of the two fluids. Results of the author do not show explosion propagation. We have therefore built a new mixing-fragmentation model based on the atomization phenomenon that develops itself during the pressure wave crossing. We have also taken into account the transient aspect of the heat transfer between fuel drops and the volatile liquid, and elaborated a model of transient heat transfer. These two models have been introduced in a multi-components, thermal, hydraulic code, MC3D. Results of calculation show a qualitative and quantitative agreement with experimental results and confirm basic options of the model. (author)

  4. THE RISE AND DECLINE OF RENT-SEEKING ACTIVITY IN THE BRAZILIAN COFFEE SECTOR: LESSONS FROM THE IMPOSITION AND REMOVAL OF COFFEE EXPORT QUOTAS

    OpenAIRE

    Jarvis, Lovell S.

    2004-01-01

    Brazil, the world's largest coffee exporter, encouraged efforts in the 1960s to form the International Coffee Agreement (ICA), which restricted total coffee exports via country export quotas. The quotas led to significant domestic quota rents in producing countries. This paper analyzes the effects of rent seeking in Brazil. The Brazilian Institute of Coffee (IBC), which was responsible for coffee policy, was the focus of rent seeking. The paper models the policy instruments used by the IB...

  5. Use of linear and areal habitat models to establish and distribute beaver Castor fiber harvest quotas in Norway

    Directory of Open Access Journals (Sweden)

    Howard Parker

    2013-12-01

    Full Text Available In Norway the Eurasian beaver Castor fiber harvest is quota-regulated. Once the annual quota for each municipality has been determined it is distributed to landowner-organized beaver management units. Municipal wildlife managers can choose between two distributional models: the traditional “areal model” whereby each management unit receives its portion of the municipal quota based on the relative area of beaver habitat within the township that it contains, or the more recently developed “linear model” based on the relative length of beaver-utilized shoreline it contains. The linear model was developed in an attempt to increase the precision of the quota distribution process and is based on the fact that beaver occupy landscapes in a linear fashion along strips of shoreline rather than exploiting extensive areas. The assumption was that the linear model would provide a more precise and just method of distributing the municipal quota among landowners. Here we test the hypothesis that the length of beaverutilized shoreline is a better predictor of beaver colony density than the area of beaver habitat on 13 beaver management units of typical size (794 – 2200 hectares in Bø Township, Norway, during 2 years. As hypothesized, the number of beaver occupied sites on management units correlated significantly (p≤ 0.001 with the length of beaver-utilized shoreline, but not with the area of beaver habitat. Therefore municipalities should employ the linear model when a precise distribution of quotas is necessary. The density of Eurasian beaver colonies at the landscape scale (>100 km2 in south-central Scandinavia averages approximately 1 occupied site per 4 km2. This figure can be employed by municipal wildlife managers to estimate the colony density in their townships, and to calculate municipal quotas, when more precise census information is lacking.

  6. Aligning the Economic Value of Companion Diagnostics and Stratified Medicines

    Directory of Open Access Journals (Sweden)

    Edward D. Blair

    2012-11-01

    Full Text Available The twin forces of payors seeking fair pricing and the rising costs of developing new medicines has driven a closer relationship between pharmaceutical companies and diagnostics companies, because stratified medicines, guided by companion diagnostics, offer better commercial, as well as clinical, outcomes. Stratified medicines have created clinical success and provided rapid product approvals, particularly in oncology, and indeed have changed the dynamic between drug and diagnostic developers. The commercial payback for such partnerships offered by stratified medicines has been less well articulated, but this has shifted as the benefits in risk management, pricing and value creation for all stakeholders become clearer. In this larger healthcare setting, stratified medicine provides both physicians and patients with greater insight on the disease and provides rationale for providers to understand cost-effectiveness of treatment. This article considers how the economic value of stratified medicine relationships can be recognized and translated into better outcomes for all healthcare stakeholders.

  7. Cotas para negros no Ensino Superior e formas de classificação racial Quotas for blacks in higher education and forms of racial classification

    Directory of Open Access Journals (Sweden)

    André Augusto Brandão

    2007-04-01

    Full Text Available Este artigo apresenta e discute dados referentes à aplicação de um questionário voltado para variáveis de classificação racial e opinião sobre a política de cotas para negros em uma amostra de 476 alunos do último ano do Ensino Médio da rede pública de um município periférico da região metropolitana do Rio de Janeiro. Buscamos compreender os elementos que informam as classificações de cor ou raça, bem como o posicionamento que esses alunos tomavam frente à política de cotas que poderia beneficiá-los no acesso a uma universidade pública. Deve-se ressaltar que os alunos entrevistados estariam em breve frente à possibilidade de disputar uma vaga no Ensino Superior em um vestibular com cotas raciais numa universidade pública que mantém um campus no próprio município onde estudam e residem. Essa problemática e esse tipo de investigação nos parecem fundamentais na atualidade, pois as cotas para negros que vêm sendo implantadas desde 2003 em várias instituições de Ensino Superior têm sofrido críticas e atravessado controvérsias jurídicas também por conta das formas de classificação propostas. Na pesquisa realizada, foi possível avançar na discussão de como as opções de classificação racial até o momento utilizadas nessas políticas se relacionam com os formatos de auto-identificação e de identificação do outro, comumente presentes no cotidiano das escolas pesquisadas, bem como verificar como a idéia de cota racial é avaliada pelos seus possíveis beneficiários.This article presents and discusses data obtained with the application of a questionnaire focused on variables for racial classification and opinion about the policy of quotas for blacks; the questionnaire was applied to a sample of 476 pupils from the last year of secondary education of the public school system of a peripheral town in the Metropolitan Area of Rio de Janeiro. We have tried to understand the elements that shape the

  8. Pricing in quota obligation schemes for renewable energy. A stochastic model with reference to the Swedish quota obligation; Preisbildung in Quotenmodellen zur Foerderung Erneuerbarer Energien. Modellierung mit stochastischem Ansatz am Beispiel des schwedischen Quotenmodells

    Energy Technology Data Exchange (ETDEWEB)

    Dees, Philipp

    2013-12-11

    The PhD thesis develops a stochastic model to explain pricing in Quota Obligation schemes for renewable energy (RE). It is based on the fact that electricity production from RE is depending on weather and other conditions, which leads to a random fluctuation. In the developed model the price for RE is depending on the probability of a lack of certificates at the end of an obligation period. In contrast to deterministic models, the stochastic model has a direct link between the price for RE and their high investment costs. Moreover, the stochastic model can be used to describe the development of prices over an obligation period. The model is adopted to the Swedish quota obligation. It is shown that the real RE prices there are much higher than the estimated prices derived from the model. This result is consistent to the fact that installed RE capacity in Sweden is much higher than necessary to fulfill the quota obligation.

  9. European Union Import Quotas on Chinese Textile and Clothing Exports in 2005

    DEFF Research Database (Denmark)

    Nedergaard, Peter

    2009-01-01

    ? The rational choice inspired model put forward in this paper assumes that the EU's political system is a partial asymmetrical political equilibrium in which decisions taken by decision makers are a product of a supply and demand. By using this model, it is explained how the lifting of quotas on Chinese textile...... and clothing exports to WTO members on 1 January, 2005 and the political situation surrounding the French referendum on the Constitutional Treaty on 29 May, 2005, constitute key events in the decision making process....

  10. The stratified H-index makes scientific impact transparent

    DEFF Research Database (Denmark)

    Würtz, Morten; Schmidt, Morten

    2017-01-01

    The H-index is widely used to quantify and standardize researchers' scientific impact. However, the H-index does not account for the fact that co-authors rarely contribute equally to a paper. Accordingly, we propose the use of a stratified H-index to measure scientific impact. The stratified H......-index supplements the conventional H-index with three separate H-indices: one for first authorships, one for second authorships and one for last authorships. The stratified H-index takes scientific output, quality and individual author contribution into account....

  11. Um modelo de otimização para alíquotas do IPTU socialmente mais justas

    Directory of Open Access Journals (Sweden)

    José Delfino Sá

    2013-02-01

    Full Text Available Este artigo apresenta um modelo de otimização matemática não linear que determina novas alíquotas para o Imposto sobre a Propriedade Predial e Territorial Urbana (IPTU incidente sobre os apartamentos residenciais no município do Salvador (BA. São considerados a progressividade das alíquotas, os valores venais dos imóveis, as rendas médias dos contribuintes e as usuais metodologias de cálculo do valor do imposto. Os resultados obtidos na aplicação desse modelo demonstram ser possível tratar de forma objetiva e socialmente mais justa a definição das alíquotas de IPTU para todos os tipos de imóveis de um município.

  12. Racial quotas in letters from readers of the “Caros Amigos” magazine: a dialogic perspective

    Directory of Open Access Journals (Sweden)

    Irene de Lima Freitas

    2013-06-01

    Full Text Available In this article we intend to demonstrate some results obtained in our dissertation, which was presented in the second semester of 2011. In the research, we analyzed texts from printed media inserted in a discursive chain of conflicts and clashes, a real platform for polemicconcerning the system of quotas in Brazil. Our purpose is to analyze the way in which the dialogic interactions are generated among the participants of the discursive event: how the author dialogues with the object of discourse and with the addressee, having as the basis for our work the Bakhtin Circle’s dialogical theory of discourse. The results highlight the fact that the positioning assumed by the interlocutors is built from the value attributed to its construction by the other; the clash among the interlocutors is constitutive of the utterances; and the dialogic analysis of the media utterances contributes to a better understanding of the social nature of discourse and of the themes which are relevant to society, in this case, the quotas.

  13. OPEC abandons quotas, more violence in Nigeria and British give away gas

    International Nuclear Information System (INIS)

    Anon

    2006-01-01

    OPEC ministers meeting in Vienna on 11th September agreed to leave the production ceiling unchanged at 28 mn bpd. The cartel, however, is to move away from formal quotas to a system of adjusting total production to world demand. The change recognizes the fact that many OPEC countries cannot produce their full quota allowances. The new policy is described by OPEC as trying ''to ensure that supply and demand (remain) in balance with prices at reasonable levels''. ''Reasonable levels'' were not defined in the communique, but most ministers agreed they should be in the region to $60-65/bbl. The oil markets were sceptical and prices fell below $60, reaching a seven-month low at the start of October. Nigeria announced a production cut of 120,000 bpd, though this may be a recognition of the difficulty of producing oil there at present. During September, the country was plagued by further violence in the Niger Delta, including attacks on oil workers, kidnappings and sabotage to oil installations. Oil workers went on strike for two days, threatening further walk-outs. By late September, nearly 875,000 bpd of production was estimated shut-in as a result of the current unrest. Shell said it had suspended plans to repair damaged facilities in the Niger Delta because of the continuing high level of violence. (author)

  14. Risks prevention and fight against the pollutions. Publication of the practical guideline of the CO{sub 2} emissions quotas market; Prevention des risques et lutte contre les pollutions. Guide pratique du marche des quotas d'emissions de CO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    Since January 2005 the directive on the emissions quotas exchange is applied in the 25 countries of the European Union. This text allocates emissions quotas to enterprises which generates many greenhouse gases. Hopeful these quotas, the European Union should decrease the emissions of 8% in 2010. This guide is devoted to the 1126 french sites concerned by the directive. It constitutes a reference for the quotas management and will help the enterprises to combine the fight against the climatic change with the economic competition. (A.L.B.)

  15. 76 FR 42160 - Allocation of Additional Fiscal Year (FY) 2011 In-Quota Volume for Raw Cane Sugar

    Science.gov (United States)

    2011-07-18

    ...-Quota Volume for Raw Cane Sugar AGENCY: Office of the United States Trade Representative. ACTION: Notice...) for imported raw cane sugar. USTR is also reallocating a portion of the unused original FY 2011 TRQ... imports of raw cane and refined sugar. Section 404(d)(3) of the Uruguay Round Agreements Act (19 U.S.C...

  16. 77 FR 57180 - Fiscal Year 2013 Tariff-rate Quota Allocations for Raw Cane Sugar, Refined and Specialty Sugar...

    Science.gov (United States)

    2012-09-17

    ... Sugar, Refined and Specialty Sugar, and Sugar-Containing Products AGENCY: Office of the United States... quantity of the tariff-rate quotas for imported raw cane sugar, refined and specialty sugar, and sugar... imports of raw cane sugar and refined sugar. Pursuant to Additional U.S. Note 8 to Chapter 17 of the HTS...

  17. 75 FR 53013 - Fiscal Year 2011 Tariff-rate Quota Allocations for Raw Cane Sugar, Refined and Specialty Sugar...

    Science.gov (United States)

    2010-08-30

    ... for Raw Cane Sugar, Refined and Specialty Sugar, and Sugar-containing Products; Revision AGENCY... August 17, 2010 concerning Fiscal Year 2011 tariff-rate quota allocations of raw cane sugar, refined and special sugar, and sugar-containing products. USTR is revising the effective date of that notice to...

  18. 75 FR 14479 - Reallocation of Unused Fiscal Year 2010 Tariff-Rate Quota Volume for Raw Cane Sugar

    Science.gov (United States)

    2010-03-25

    ...-Rate Quota Volume for Raw Cane Sugar AGENCY: Office of the United States Trade Representative. ACTION... (TRQ) for imported raw cane sugar. DATES: Effective Date: March 25, 2010. ADDRESSES: Inquiries may be... (HTS), the United States maintains TRQs for imports of raw cane and refined sugar. Section 404(d)(3) of...

  19. 75 FR 26316 - Allocation of Additional Fiscal Year (FY) 2010 In-Quota Volume for Raw Cane Sugar

    Science.gov (United States)

    2010-05-11

    ...-Quota Volume for Raw Cane Sugar AGENCY: Office of the United States Trade Representative. ACTION: Notice...) for imported raw cane sugar. DATES: Effective Date: May 11, 2010. ADDRESSES: Inquiries may be mailed... (HTS), the United States maintains TRQs for imports of raw cane and refined sugar. Section 404(d)(3) of...

  20. Estimating the Costs to Consumers of the U.S. Sugar Quota: An Exercise for Introductory Economics Classes.

    Science.gov (United States)

    Williams, Andrew T.

    1997-01-01

    Provides a classroom exercise using the restrictive tariffs on sugar to examine issues of protectionism and international trade. Discusses related issues such as the North American Free Trade Agreement and the formation of large regional trading blocks. Includes a hands-on calculation of the economic impact of the quota on consumers. (MJP)

  1. 76 FR 59663 - Limitations of Duty- and Quota-Free Imports of Apparel Articles Assembled in Beneficiary Sub...

    Science.gov (United States)

    2011-09-27

    ... of Apparel Articles Assembled in Beneficiary Sub-Saharan African Countries From Regional and Third... Acceleration Act of 2004, Pub. L. 108-274; Division D, Title VI, section 6002 of the Tax Relief and Health Care... beneficiary sub-Saharan African countries. Section 112(b)(3) of TDA 2000 provides duty- and quota-free...

  2. 75 FR 1589 - Amendment of Limitation of Duty- and Quota-Free Imports of Apparel Articles Assembled in...

    Science.gov (United States)

    2010-01-12

    ... on duty- and quota-free benefits. DATES: Effective Date: January 1, 2010. FOR FURTHER INFORMATION CONTACT: Richard Stetson, International Trade Specialist, Office of Textiles and Apparel, U.S. Department of Commerce, (202) 482-3400. SUPPLEMENTARY INFORMATION: Authority: Section 3103 of the Trade Act of...

  3. 77 FR 59913 - Limitations of Duty- and Quota-Free Imports of Apparel Articles Assembled in Beneficiary Sub...

    Science.gov (United States)

    2012-10-01

    ... the new 12-month cap on duty- and quota-free benefits. DATES: Effective October 1, 2012. FOR FURTHER INFORMATION CONTACT: Don Niewiaroski, Jr., International Trade Specialist, Office of Textiles and Apparel, U.S... the Trade and Development Act of 2000 (TDA 2000), Public Law 106-200, as amended by Division B, Title...

  4. 76 FR 66915 - Amendment of Limitation of Duty- and Quota-Free Imports of Apparel Articles Assembled in...

    Science.gov (United States)

    2011-10-28

    ... on Duty and Quota Free Benefits. DATES: Effective Date: February 13, 2011. FOR FURTHER INFORMATION CONTACT: Richard Stetson, International Trade Specialist, Office of Textiles and Apparel, U.S. Department of Commerce, (202) 482-3400. SUPPLEMENTARY INFORMATION: Authority: Section 3103 of the Trade Act of...

  5. 76 FR 66914 - Amendment of Limitation of Duty- and Quota-Free Imports of Apparel Articles Assembled in...

    Science.gov (United States)

    2011-10-28

    ... Cap on Duty and Quota Free Benefits. DATES: Effective Date: October 1, 2011. FOR FURTHER INFORMATION CONTACT: Richard Stetson, International Trade Specialist, Office of Textiles and Apparel, U.S. Department of Commerce, (202) 482-3400. SUPPLEMENTARY INFORMATION: Authority: Section 3103 of the Trade Act of...

  6. Quota regime for renewable energy sources and Green Labels trading in the electricity market of the Netherlands

    International Nuclear Information System (INIS)

    Drillisch, J.

    1998-01-01

    The renewables quota regime combined with a ''green electricity'' labelling and trading system, implemented by the Dutch association of distribution undertakings, is the first of its kind in Europe. The distribution undertakings are bound by a commitment to take and distribute ''green label'' electricity from renewables amounting to approx. 3% of their total sales to contractual customers. This is a modest percentage, but the quota regime already proved to be a promoter of close-to-the-market generation technologies. It would be too early now to make a final statement on the quota regime's influence on enhanced use of renewable energy sources. Practice so far also revealed the need for some modifications in the design of the pricing system for''green electricity''. Current debates consider integration of renewable energy sources abroad. The first accounting date for giving evidence of compliance with the commitment to green label quotas is late in the year 2000. This will be the test for the system and the efficiency of sanctions provided for in case of non-compliance. It will be a task of the future to examine whether it might be appropriate to establish a similar system for the heat market. (RHM/CB) [de

  7. 7 CFR 718.206 - Determining farms, tracts, allotments, quotas, and bases when reconstitution is made by division.

    Science.gov (United States)

    2010-01-01

    ... transferring owner and transferee shall file a signed written memorandum of understanding of the designation... allotments, quotas, and bases shall be apportioned in the manner agreed to in writing by all interested heirs... totals of the parent farm than the cropland method would; and (ii) Obtains written consent of all owners...

  8. 76 FR 1137 - Amendment of Limitation of Duty- and Quota-Free Imports of Apparel Articles Assembled in...

    Science.gov (United States)

    2011-01-07

    ... Annex to the World Trade Organization Agreement on Textiles and Clothing (ATC), and the conversion... COMMITTEE FOR THE IMPLEMENTATION OF TEXTILE AGREEMENTS Amendment of Limitation of Duty- and Quota-Free Imports of Apparel Articles Assembled in Beneficiary ATPDEA Countries From Regional Country Fabric...

  9. 75 FR 60066 - Limitations of Duty- and Quota-Free Imports of Apparel Articles Assembled in Beneficiary ATPDEA...

    Science.gov (United States)

    2010-09-29

    ... set of Harmonized System lines listed in the Annex to the World Trade Organization Agreement on... COMMITTEE FOR THE IMPLEMENTATION OF TEXTILE AGREEMENTS Limitations of Duty- and Quota-Free Imports of Apparel Articles Assembled in Beneficiary ATPDEA Countries From Regional Country Fabric AGENCY...

  10. Problemi dei contingenti all'importazione (The problem with import quotas

    Directory of Open Access Journals (Sweden)

    V. BARATTIERI

    2014-03-01

    Full Text Available Today trade policy and the politics of protectionism in Italy, for the most part carried out within the EEC, essentially rely on the Community system of customs duties on imported products and variable taxes on agricultural imports. However, there is also a set of domestic trade policy instruments, among which the system of quantitative import restrictions. The present article analyzes the economic, legal and practical aspects of the complex problem of the allocation of import licenses between national operators. In the first part the authors summarize the main differences between quotas and customs duties. The formulas adopted to date in Italy are then re-examined and the criteria used by the other CEE countries are referred to. Finally, the objectives identified as priorities in the field of Public Administration are specified, the main shortcomings of the current system highlighted and some changes proposed.  JEL: F13, F15

  11. A human-scale perspective on global warming: Zero emission year and personal quotas

    Science.gov (United States)

    Rojas, Maisa; Mac Lean, Claudia

    2017-01-01

    This article builds on the premise that human consumption of goods, food and transport are the ultimate drivers of climate change. However, the nature of the climate change problem (well described as a tragedy of the commons) makes it difficult for individuals to recognise their personal duty to implement behavioural changes to reduce greenhouse gas emissions. Consequently, this article aims to analyse the climate change issue from a human-scale perspective, in which each of us has a clearly defined personal quota of CO2 emissions that limits our activity and there is a finite time during which CO2 emissions must be eliminated to achieve the “well below 2°C” warming limit set by the Paris Agreement of 2015 (COP21). Thus, this work’s primary contribution is to connect an equal per capita fairness approach to a global carbon budget, linking personal levels with planetary levels. Here, we show that a personal quota of 5.0 tons of CO2 yr-1 p-1 is a representative value for both past and future emissions; for this level of a constant per-capita emissions and without considering any mitigation, the global accumulated emissions compatible with the “well below 2°C” and 2°C targets will be exhausted by 2030 and 2050, respectively. These are references years that provide an order of magnitude of the time that is left to reverse the global warming trend. More realistic scenarios that consider a smooth transition toward a zero-emission world show that the global accumulated emissions compatible with the “well below 2°C” and 2°C targets will be exhausted by 2040 and 2080, respectively. Implications of this paper include a return to personal responsibility following equity principles among individuals, and a definition of boundaries to the personal emissions of CO2. PMID:28628676

  12. A human-scale perspective on global warming: Zero emission year and personal quotas.

    Science.gov (United States)

    de la Fuente, Alberto; Rojas, Maisa; Mac Lean, Claudia

    2017-01-01

    This article builds on the premise that human consumption of goods, food and transport are the ultimate drivers of climate change. However, the nature of the climate change problem (well described as a tragedy of the commons) makes it difficult for individuals to recognise their personal duty to implement behavioural changes to reduce greenhouse gas emissions. Consequently, this article aims to analyse the climate change issue from a human-scale perspective, in which each of us has a clearly defined personal quota of CO2 emissions that limits our activity and there is a finite time during which CO2 emissions must be eliminated to achieve the "well below 2°C" warming limit set by the Paris Agreement of 2015 (COP21). Thus, this work's primary contribution is to connect an equal per capita fairness approach to a global carbon budget, linking personal levels with planetary levels. Here, we show that a personal quota of 5.0 tons of CO2 yr-1 p-1 is a representative value for both past and future emissions; for this level of a constant per-capita emissions and without considering any mitigation, the global accumulated emissions compatible with the "well below 2°C" and 2°C targets will be exhausted by 2030 and 2050, respectively. These are references years that provide an order of magnitude of the time that is left to reverse the global warming trend. More realistic scenarios that consider a smooth transition toward a zero-emission world show that the global accumulated emissions compatible with the "well below 2°C" and 2°C targets will be exhausted by 2040 and 2080, respectively. Implications of this paper include a return to personal responsibility following equity principles among individuals, and a definition of boundaries to the personal emissions of CO2.

  13. The effect of existing turbulence on stratified shear instability

    Science.gov (United States)

    Kaminski, Alexis; Smyth, William

    2017-11-01

    Ocean turbulence is an essential process governing, for example, heat uptake by the ocean. In the stably-stratified ocean interior, this turbulence occurs in discrete events driven by vertical variations of the horizontal velocity. Typically, these events have been modelled by assuming an initially laminar stratified shear flow which develops wavelike instabilities, becomes fully turbulent, and then relaminarizes into a stable state. However, in the real ocean there is always some level of turbulence left over from previous events, and it is not yet understood how this turbulence impacts the evolution of future mixing events. Here, we perform a series of direct numerical simulations of turbulent events developing in stratified shear flows that are already at least weakly turbulent. We do so by varying the amplitude of the initial perturbations, and examine the subsequent development of the instability and the impact on the resulting turbulent fluxes. This work is supported by NSF Grant OCE1537173.

  14. Modern survey sampling

    CERN Document Server

    Chaudhuri, Arijit

    2014-01-01

    Exposure to SamplingAbstract Introduction Concepts of Population, Sample, and SamplingInitial RamificationsAbstract Introduction Sampling Design, Sampling SchemeRandom Numbers and Their Uses in Simple RandomSampling (SRS)Drawing Simple Random Samples with and withoutReplacementEstimation of Mean, Total, Ratio of Totals/Means:Variance and Variance EstimationDetermination of Sample SizesA.2 Appendix to Chapter 2 A.More on Equal Probability Sampling A.Horvitz-Thompson EstimatorA.SufficiencyA.LikelihoodA.Non-Existence Theorem More Intricacies Abstract Introduction Unequal Probability Sampling StrategiesPPS Sampling Exploring Improved WaysAbstract Introduction Stratified Sampling Cluster SamplingMulti-Stage SamplingMulti-Phase Sampling: Ratio and RegressionEstimationviiviii ContentsControlled SamplingModeling Introduction Super-Population ModelingPrediction Approach Model-Assisted Approach Bayesian Methods Spatial SmoothingSampling on Successive Occasions: Panel Rotation Non-Response and Not-at-Homes Weighting Adj...

  15. Large eddy simulation of turbulent and stably-stratified flows

    International Nuclear Information System (INIS)

    Fallon, Benoit

    1994-01-01

    The unsteady turbulent flow over a backward-facing step is studied by mean of Large Eddy Simulations with structure function sub grid model, both in isothermal and stably-stratified configurations. Without stratification, the flow develops highly-distorted Kelvin-Helmholtz billows, undergoing to helical pairing, with A-shaped vortices shed downstream. We show that forcing injected by recirculation fluctuations governs this oblique mode instabilities development. The statistical results show good agreements with the experimental measurements. For stably-stratified configurations, the flow remains more bi-dimensional. We show with increasing stratification, how the shear layer growth is frozen by inhibition of pairing process then of Kelvin-Helmholtz instabilities, and the development of gravity waves or stable density interfaces. Eddy structures of the flow present striking analogies with the stratified mixing layer. Additional computations show the development of secondary Kelvin-Helmholtz instabilities on the vorticity layers between two primary structures. This important mechanism based on baroclinic effects (horizontal density gradients) constitutes an additional part of the turbulent mixing process. Finally, the feasibility of Large Eddy Simulation is demonstrated for industrial flows, by studying a complex stratified cavity. Temperature fluctuations are compared to experimental measurements. We also develop three-dimensional un-stationary animations, in order to understand and visualize turbulent interactions. (author) [fr

  16. Bacterial production, protozoan grazing, and mineralization in stratified Lake Vechten

    NARCIS (Netherlands)

    Bloem, J.

    1989-01-01

    The role of heterotrophic nanoflagellates (HNAN, size 2-20 μm) in grazing on bacteria and mineralization of organic matter in stratified Lake Vechten was studied.

    Quantitative effects of manipulation and fixation on HNAN were checked. Considerable losses were caused by

  17. The dynamics of small inertial particles in weakly stratified turbulence

    NARCIS (Netherlands)

    van Aartrijk, M.; Clercx, H.J.H.

    We present an overview of a numerical study on the small-scale dynamics and the large-scale dispersion of small inertial particles in stably stratified turbulence. Three types of particles are examined: fluid particles, light inertial particles (with particle-to-fluid density ratio 1Ͽp/Ͽf25) and

  18. Dispersion of (light) inertial particles in stratified turbulence

    NARCIS (Netherlands)

    van Aartrijk, M.; Clercx, H.J.H.; Armenio, Vincenzo; Geurts, Bernardus J.; Fröhlich, Jochen

    2010-01-01

    We present a brief overview of a numerical study of the dispersion of particles in stably stratified turbulence. Three types of particles arc examined: fluid particles, light inertial particles ($\\rho_p/\\rho_f = \\mathcal{O}(1)$) and heavy inertial particles ($\\rho_p/\\rho_f \\gg 1$). Stratification

  19. Stability of Miscible Displacements Across Stratified Porous Media

    Energy Technology Data Exchange (ETDEWEB)

    Shariati, Maryam; Yortsos, Yanis C.

    2000-09-11

    This report studied macro-scale heterogeneity effects. Reflecting on their importance, current simulation practices of flow and displacement in porous media were invariably based on heterogeneous permeability fields. Here, it was focused on a specific aspect of such problems, namely the stability of miscible displacements in stratified porous media, where the displacement is perpendicular to the direction of stratification.

  20. On Internal Waves in a Density-Stratified Estuary

    NARCIS (Netherlands)

    Kranenburg, C.

    1991-01-01

    In this article some field observations, made in recent years, of internal wave motions in a density-stratified estuary are presented, In order to facilitate the appreciation of the results, and to make some quantitative comparisons, the relevant theory is also summarized. Furthermore, the origins

  1. FDTD scattered field formulation for scatterers in stratified dispersive media.

    Science.gov (United States)

    Olkkonen, Juuso

    2010-03-01

    We introduce a simple scattered field (SF) technique that enables finite difference time domain (FDTD) modeling of light scattering from dispersive objects residing in stratified dispersive media. The introduced SF technique is verified against the total field scattered field (TFSF) technique. As an application example, we study surface plasmon polariton enhanced light transmission through a 100 nm wide slit in a silver film.

  2. Plane Stratified Flow in a Room Ventilated by Displacement Ventilation

    DEFF Research Database (Denmark)

    Nielsen, Peter Vilhelm; Nickel, J.; Baron, D. J. G.

    2004-01-01

    The air movement in the occupied zone of a room ventilated by displacement ventilation exists as a stratified flow along the floor. This flow can be radial or plane according to the number of wall-mounted diffusers and the room geometry. The paper addresses the situations where plane flow...

  3. Dual Spark Plugs For Stratified-Charge Rotary Engine

    Science.gov (United States)

    Abraham, John; Bracco, Frediano V.

    1996-01-01

    Fuel efficiency of stratified-charge, rotary, internal-combustion engine increased by improved design featuring dual spark plugs. Second spark plug ignites fuel on upstream side of main fuel injector; enabling faster burning and more nearly complete utilization of fuel.

  4. Prognosis research strategy (PROGRESS) 4: Stratified medicine research

    NARCIS (Netherlands)

    A. Hingorani (Aroon); D.A.W.M. van der Windt (Daniëlle); R.D. Riley (Richard); D. Abrams; K.G.M. Moons (Karel); E.W. Steyerberg (Ewout); S. Schroter (Sara); W. Sauerbrei (Willi); D.G. Altman (Douglas); H. Hemingway; A. Briggs (Andrew); N. Brunner; P. Croft (Peter); J. Hayden (Jill); P.A. Kyzas (Panayiotis); N. Malats (Núria); G. Peat; P. Perel (Pablo); I. Roberts (Ian); A. Timmis (Adam)

    2013-01-01

    textabstractIn patients with a particular disease or health condition, stratified medicine seeks to identify thosewho will have the most clinical benefit or least harm from a specific treatment. In this article, thefourth in the PROGRESS series, the authors discuss why prognosis research should form

  5. Impressions of the turbulence variability in a weakly stratified, flat-bottom deep-sea ‘boundary layer’

    NARCIS (Netherlands)

    van Haren, H.

    2015-01-01

    The character of turbulent overturns in a weakly stratified deep-sea is investigated in some detail using 144 high-resolution temperature sensors at 0.7 m intervals, starting 5 m above the bottom. A 9-day, 1 Hz sampled record from the 912 m depth flat-bottom (<0.5% bottom-slope) mooring site in the

  6. Exploring the role of wave drag in the stable stratified oceanic and atmospheric bottom boundary layer in the cnrs-toulouse (cnrm-game) large stratified water flume

    NARCIS (Netherlands)

    Kleczek, M.; Steeneveld, G.J.; Paci, A.; Calmer, R.; Belleudy, A.; Canonici, J.C.; Murguet, F.; Valette, V.

    2014-01-01

    This paper reports on a laboratory experiment in the CNRM-GAME (Toulouse) stratified water flume of a stably stratified boundary layer, in order to quantify the momentum transfer due to orographically induced gravity waves by gently undulating hills in a boundary layer flow. In a stratified fluid, a

  7. CO2 Capture Rate Sensitivity Versus Purchase of CO2 Quotas. Optimizing Investment Choice for Electricity Sector

    Directory of Open Access Journals (Sweden)

    Coussy Paula

    2014-09-01

    Full Text Available Carbon capture technology (and associated storage, applied to power plants, reduces atmospheric CO2 emissions. This article demonstrates that, in the particular case of the deployment phase of CO2 capture technology during which CO2 quota price may be low, capturing less than 90% of total CO2 emissions from power plants can be economically attractive. Indeed, for an electric power company capture technology is interesting, only if the discounted marginal cost of capture is lower than the discounted marginal cost of purchased quotas. When CO2 price is low, it is interesting to have flexibility and reduce the overall capture rate of the site, by stopping the capture system of one of the combustion trains if the site has multiple ones, or by adopting less than 90% CO2 capture rate.

  8. Incentivising selective fishing under catch quotas: using an FCube modelling approach to evaluate management options for North Sea mixed fisheries

    DEFF Research Database (Denmark)

    Condie, Harriet M.; Dolder, Paul J.; Catchpole, Thomas L.

    Reforms of EU Common Fisheries Policy will make fundamental changes to European fisheries management, including a discard ban with catch quotas for regulated species and management to achieve MSY. We evaluate the impact of these changes on revenue of North Sea demersal finfish fleets and fish...... stocks. With no change in behaviour, revenue is reduced by a mean of 31% compared to current management in the first year, but partly recovers by year 3, as fishing mortality is reduced and stocks increase. There are large differences in revenue changes between fleets, varying from -99% to +36...... in revenue create a strong incentive to avoid catching the limiting species, particularly if it is not a primary target. Selectivity changes that avoid 30% cod catch reduced the economic impact for some fleets in moving to catch quotas. Increased flexibility will therefore be important in maintaining...

  9. Simulation of steam explosion in stratified melt-coolant configuration

    International Nuclear Information System (INIS)

    Leskovar, Matjaž; Centrih, Vasilij; Uršič, Mitja

    2016-01-01

    Highlights: • Strong steam explosions may develop spontaneously in stratified configurations. • Considerable melt-coolant premixed layer formed in subcooled water with hot melts. • Analysis with MC3D code provided insight into stratified steam explosion phenomenon. • Up to 25% of poured melt was mixed with water and available for steam explosion. • Better instrumented experiments needed to determine dominant mixing process. - Abstract: A steam explosion is an energetic fuel coolant interaction process, which may occur during a severe reactor accident when the molten core comes into contact with the coolant water. In nuclear reactor safety analyses steam explosions are primarily considered in melt jet-coolant pool configurations where sufficiently deep coolant pool conditions provide complete jet breakup and efficient premixture formation. Stratified melt-coolant configurations, i.e. a molten melt layer below a coolant layer, were up to now believed as being unable to generate strong explosive interactions. Based on the hypothesis that there are no interfacial instabilities in a stratified configuration it was assumed that the amount of melt in the premixture is insufficient to produce strong explosions. However, the recently performed experiments in the PULiMS and SES (KTH, Sweden) facilities with oxidic corium simulants revealed that strong steam explosions may develop spontaneously also in stratified melt-coolant configurations, where with high temperature melts and subcooled water conditions a considerable melt-coolant premixed layer is formed. In the article, the performed study of steam explosions in a stratified melt-coolant configuration in PULiMS like conditions is presented. The goal of this analytical work is to supplement the experimental activities within the PULiMS research program by addressing the key questions, especially regarding the explosivity of the formed premixed layer and the mechanisms responsible for the melt-water mixing. To

  10. Structuring a Multiproduct Sales Quota-Bonus Plan for a Heterogeneous Sales Force: A Practical Model-Based Approach

    OpenAIRE

    Murali K. Mantrala; Prabhakant Sinha; Andris A. Zoltners

    1994-01-01

    This paper presents an agency theoretic model-based approach that assists sales managers in determining the profit-maximizing structure of a common multiproduct sales quota-bonus plan for a geographically specialized heterogeneous sales force operating in a repetitive buying environment. This approach involves estimating each salesperson's utility function for income and effort and using these models to predict individual sales achievements and the associated aggregate profit for the firm und...

  11. Gender balance on company boards: a summary from a research project about the impact of the Norwegian gender quota legislation

    OpenAIRE

    2015-01-01

    This report summarizes main findings from the research project: Effects of gender balance in corporate boards. The project is financed by the Ministry of Children, Equality and Social Inclusion. The report consists of nine chapters. The introductory chapter will provide key information about the gender quota legislation, as well as describe the policy process that led to the gender balance legislation; the second chapter will present some of the existing research on the gender balance regulat...

  12. Implementing a system of emissions trading to manage GHGs; La mise en oeuvre des systemes de quotas d'emission echangeables dans la gestion des emissions de GES

    Energy Technology Data Exchange (ETDEWEB)

    Webster, A. [Sherbrooke Univ., PQ (Canada)

    2005-06-01

    The exact geographical location of greenhouse gas (GHG) emissions has no bearing on climate change. In this context the Kyoto Protocol recognizes mechanisms of flexibility for countries to attain their GHG emissions reductions. Emission trading takes advantage of this flexibility, allowing GHGs to be sold, traded, or stockpiled. An emission quota allows the owner of an energy facility to emit a certain amount of GHGs throughout the year. If this quota is not used, it can be stockpiled for the following year or it could be traded to another enterprise and owner. If the amount of emissions exceeds the initial quotas, facilities can adopt different strategies, such as reducing their GHG purchasing quotas from national enterprises that have reduced their emissions or purchase quotas from international markets. The initial allocation of quotas is an important political decision since it determines the initial distribution of the GHG reduction effort. The establishment of a quota system can contribute to economical competition and can be used to fulfill environmental objectives regarding energy source development. It is also the most effective way to minimize greenhouse gas emissions and the associated environmental impacts. This paper reviewed the regulations regarding the design of the quota system; how the ceiling of emission levels was determined; the criteria for allocating the quotas and the rules for the exchange of emission quotas. Canada and the European countries have expressed interest in this system of emissions trading. 7 refs.

  13. Identification of major planktonic sulfur oxidizers in stratified freshwater lake.

    Directory of Open Access Journals (Sweden)

    Hisaya Kojima

    Full Text Available Planktonic sulfur oxidizers are important constituents of ecosystems in stratified water bodies, and contribute to sulfide detoxification. In contrast to marine environments, taxonomic identities of major planktonic sulfur oxidizers in freshwater lakes still remain largely unknown. Bacterioplankton community structure was analyzed in a stratified freshwater lake, Lake Mizugaki in Japan. In the clone libraries of 16S rRNA gene, clones very closely related to a sulfur oxidizer isolated from this lake, Sulfuritalea hydrogenivorans, were detected in deep anoxic water, and occupied up to 12.5% in each library of different water depth. Assemblages of planktonic sulfur oxidizers were specifically analyzed by constructing clone libraries of genes involved in sulfur oxidation, aprA, dsrA, soxB and sqr. In the libraries, clones related to betaproteobacteria were detected with high frequencies, including the close relatives of Sulfuritalea hydrogenivorans.

  14. Study of MRI in stratified viscous plasma configuration

    Science.gov (United States)

    Carlevaro, Nakia; Montani, Giovanni; Renzi, Fabrizio

    2017-02-01

    We analyze the morphology of the magneto-rotational instability (MRI) for a stratified viscous plasma disk configuration in differential rotation, taking into account the so-called corotation theorem for the background profile. In order to select the intrinsic Alfvénic nature of MRI, we deal with an incompressible plasma and we adopt a formulation of the local perturbation analysis based on the use of the magnetic flux function as a dynamical variable. Our study outlines, as consequence of the corotation condition, a marked asymmetry of the MRI with respect to the equatorial plane, particularly evident in a complete damping of the instability over a positive critical height on the equatorial plane. We also emphasize how such a feature is already present (although less pronounced) even in the ideal case, restoring a dependence of the MRI on the stratified morphology of the gravitational field.

  15. Mixing of stratified flow around bridge piers in steady current

    DEFF Research Database (Denmark)

    Jensen, Bjarne; Carstensen, Stefan; Christensen, Erik Damgaard

    2018-01-01

    This paper presents the results of an experimental and numerical investigation of the mixing of stratified flow around bridge pier structures. In this study, which was carried out in connection with the Fehmarnbelt Fixed Link environmental impact assessment, the mixing processes of two-layer stra......This paper presents the results of an experimental and numerical investigation of the mixing of stratified flow around bridge pier structures. In this study, which was carried out in connection with the Fehmarnbelt Fixed Link environmental impact assessment, the mixing processes of two......-layer stratification was studied in which the lower level had a higher salinity than the upper layer. The physical experiments investigated two different pier designs. A general study was made regarding forces on the piers in which the effect of the current angle relative to the structure was also included...

  16. Stratified charge rotary aircraft engine technology enablement program

    Science.gov (United States)

    Badgley, P. R.; Irion, C. E.; Myers, D. M.

    1985-01-01

    The multifuel stratified charge rotary engine is discussed. A single rotor, 0.7L/40 cu in displacement, research rig engine was tested. The research rig engine was designed for operation at high speeds and pressures, combustion chamber peak pressure providing margin for speed and load excursions above the design requirement for a high is advanced aircraft engine. It is indicated that the single rotor research rig engine is capable of meeting the established design requirements of 120 kW, 8,000 RPM, 1,379 KPA BMEP. The research rig engine, when fully developed, will be a valuable tool for investigating, advanced and highly advanced technology components, and provide an understanding of the stratified charge rotary engine combustion process.

  17. Analysis of photonic band-gap structures in stratified medium

    DEFF Research Database (Denmark)

    Tong, Ming-Sze; Yinchao, Chen; Lu, Yilong

    2005-01-01

    in electromagnetic and microwave applications once the Maxwell's equations are appropriately modeled. Originality/value - The method validates its values and properties through extensive studies on regular and defective 1D PBG structures in stratified medium, and it can be further extended to solving more......Purpose - To demonstrate the flexibility and advantages of a non-uniform pseudo-spectral time domain (nu-PSTD) method through studies of the wave propagation characteristics on photonic band-gap (PBG) structures in stratified medium Design/methodology/approach - A nu-PSTD method is proposed...... in solving the Maxwell's equations numerically. It expands the temporal derivatives using the finite differences, while it adopts the Fourier transform (FT) properties to expand the spatial derivatives in Maxwell's equations. In addition, the method makes use of the chain-rule property in calculus together...

  18. Community genomics among stratified microbial assemblages in the ocean's interior

    DEFF Research Database (Denmark)

    DeLong, Edward F; Preston, Christina M; Mincer, Tracy

    2006-01-01

    Microbial life predominates in the ocean, yet little is known about its genomic variability, especially along the depth continuum. We report here genomic analyses of planktonic microbial communities in the North Pacific Subtropical Gyre, from the ocean's surface to near-sea floor depths. Sequence......, and host-viral interactions. Comparative genomic analyses of stratified microbial communities have the potential to provide significant insight into higher-order community organization and dynamics....

  19. Large Eddy Simulation of stratified flows over structures

    OpenAIRE

    Brechler J.; Fuka V.

    2013-01-01

    We tested the ability of the LES model CLMM (Charles University Large-Eddy Microscale Model) to model the stratified flow around three dimensional hills. We compared the quantities, as the height of the dividing streamline, recirculation zone length or length of the lee waves with experiments by Hunt and Snyder[3] and numerical computations by Ding, Calhoun and Street[5]. The results mostly agreed with the references, but some important differences are present.

  20. Large Eddy Simulation of stratified flows over structures

    Directory of Open Access Journals (Sweden)

    Brechler J.

    2013-04-01

    Full Text Available We tested the ability of the LES model CLMM (Charles University Large-Eddy Microscale Model to model the stratified flow around three dimensional hills. We compared the quantities, as the height of the dividing streamline, recirculation zone length or length of the lee waves with experiments by Hunt and Snyder[3] and numerical computations by Ding, Calhoun and Street[5]. The results mostly agreed with the references, but some important differences are present.

  1. Large Eddy Simulation of stratified flows over structures

    Science.gov (United States)

    Fuka, V.; Brechler, J.

    2013-04-01

    We tested the ability of the LES model CLMM (Charles University Large-Eddy Microscale Model) to model the stratified flow around three dimensional hills. We compared the quantities, as the height of the dividing streamline, recirculation zone length or length of the lee waves with experiments by Hunt and Snyder[3] and numerical computations by Ding, Calhoun and Street[5]. The results mostly agreed with the references, but some important differences are present.

  2. Propagation of acoustic waves in a stratified atmosphere, 1

    Science.gov (United States)

    Kalkofen, W.; Rossi, P.; Bodo, G.; Massaglia, S.

    1994-01-01

    This work is motivated by the chromospheric 3 minute oscillations observed in the K(sub 2v) bright points. We study acoustic gravity waves in a one-dimensional, gravitationally stratified, isothermal atmosphere. The oscillations are excited either by a velocity pulse imparted to a layer in an atmosphere of infinite vertical extent, or by a piston forming the lower boundary of a semi-infinite medium. We consider both linear and non-linear waves.

  3. A statistical mechanics approach to mixing in stratified fluids

    OpenAIRE

    Venaille , Antoine; Gostiaux , Louis; Sommeria , Joël

    2016-01-01

    Accepted for the Journal of Fluid Mechanics; Predicting how much mixing occurs when a given amount of energy is injected into a Boussinesq fluid is a longstanding problem in stratified turbulence. The huge number of degrees of freedom involved in these processes renders extremely difficult a deterministic approach to the problem. Here we present a statistical mechanics approach yielding a prediction for a cumulative, global mixing efficiency as a function of a global Richard-son number and th...

  4. Sutudy on exchange flow under the unstably stratified field

    OpenAIRE

    文沢, 元雄

    2005-01-01

    This paper deals with the exchange flow under the unstably stratified field. The author developed the effective measurement system as well as the numerical analysis program. The system and the program are applied to the helium-air exchange flow in a rectangular channel with inclination. Following main features of the exchange flow were discussed based on the calculated results.(1) Time required for establishing a quasi-steady state exchange flow.(2) The relationship between the inclination an...

  5. Background stratified Poisson regression analysis of cohort data.

    Science.gov (United States)

    Richardson, David B; Langholz, Bryan

    2012-03-01

    Background stratified Poisson regression is an approach that has been used in the analysis of data derived from a variety of epidemiologically important studies of radiation-exposed populations, including uranium miners, nuclear industry workers, and atomic bomb survivors. We describe a novel approach to fit Poisson regression models that adjust for a set of covariates through background stratification while directly estimating the radiation-disease association of primary interest. The approach makes use of an expression for the Poisson likelihood that treats the coefficients for stratum-specific indicator variables as 'nuisance' variables and avoids the need to explicitly estimate the coefficients for these stratum-specific parameters. Log-linear models, as well as other general relative rate models, are accommodated. This approach is illustrated using data from the Life Span Study of Japanese atomic bomb survivors and data from a study of underground uranium miners. The point estimate and confidence interval obtained from this 'conditional' regression approach are identical to the values obtained using unconditional Poisson regression with model terms for each background stratum. Moreover, it is shown that the proposed approach allows estimation of background stratified Poisson regression models of non-standard form, such as models that parameterize latency effects, as well as regression models in which the number of strata is large, thereby overcoming the limitations of previously available statistical software for fitting background stratified Poisson regression models.

  6. Ethanol dehydration to ethylene in a stratified autothermal millisecond reactor.

    Science.gov (United States)

    Skinner, Michael J; Michor, Edward L; Fan, Wei; Tsapatsis, Michael; Bhan, Aditya; Schmidt, Lanny D

    2011-08-22

    The concurrent decomposition and deoxygenation of ethanol was accomplished in a stratified reactor with 50-80 ms contact times. The stratified reactor comprised an upstream oxidation zone that contained Pt-coated Al(2)O(3) beads and a downstream dehydration zone consisting of H-ZSM-5 zeolite films deposited on Al(2)O(3) monoliths. Ethanol conversion, product selectivity, and reactor temperature profiles were measured for a range of fuel:oxygen ratios for two autothermal reactor configurations using two different sacrificial fuel mixtures: a parallel hydrogen-ethanol feed system and a series methane-ethanol feed system. Increasing the amount of oxygen relative to the fuel resulted in a monotonic increase in ethanol conversion in both reaction zones. The majority of the converted carbon was in the form of ethylene, where the ethanol carbon-carbon bonds stayed intact while the oxygen was removed. Over 90% yield of ethylene was achieved by using methane as a sacrificial fuel. These results demonstrate that noble metals can be successfully paired with zeolites to create a stratified autothermal reactor capable of removing oxygen from biomass model compounds in a compact, continuous flow system that can be configured to have multiple feed inputs, depending on process restrictions. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Background stratified Poisson regression analysis of cohort data

    International Nuclear Information System (INIS)

    Richardson, David B.; Langholz, Bryan

    2012-01-01

    Background stratified Poisson regression is an approach that has been used in the analysis of data derived from a variety of epidemiologically important studies of radiation-exposed populations, including uranium miners, nuclear industry workers, and atomic bomb survivors. We describe a novel approach to fit Poisson regression models that adjust for a set of covariates through background stratification while directly estimating the radiation-disease association of primary interest. The approach makes use of an expression for the Poisson likelihood that treats the coefficients for stratum-specific indicator variables as 'nuisance' variables and avoids the need to explicitly estimate the coefficients for these stratum-specific parameters. Log-linear models, as well as other general relative rate models, are accommodated. This approach is illustrated using data from the Life Span Study of Japanese atomic bomb survivors and data from a study of underground uranium miners. The point estimate and confidence interval obtained from this 'conditional' regression approach are identical to the values obtained using unconditional Poisson regression with model terms for each background stratum. Moreover, it is shown that the proposed approach allows estimation of background stratified Poisson regression models of non-standard form, such as models that parameterize latency effects, as well as regression models in which the number of strata is large, thereby overcoming the limitations of previously available statistical software for fitting background stratified Poisson regression models. (orig.)

  8. Numerical simulations of the stratified oceanic bottom boundary layer

    Science.gov (United States)

    Taylor, John R.

    Numerical simulations are used to consider several problems relevant to the turbulent oceanic bottom boundary layer. In the first study, stratified open channel flow is considered with thermal boundary conditions chosen to approximate a shallow sea. Specifically, a constant heat flux is applied at the free surface and the lower wall is assumed to be adiabatic. When the surface heat flux is strong, turbulent upwellings of low speed fluid from near the lower wall are inhibited by the stable stratification. Subsequent studies consider a stratified bottom Ekman layer over a non-sloping lower wall. The influence of the free surface is removed by using an open boundary condition at the top of the computational domain. Particular attention is paid to the influence of the outer layer stratification on the boundary layer structure. When the density field is initialized with a linear profile, a turbulent mixed layer forms near the wall, which is separated from the outer layer by a strongly stable pycnocline. It is found that the bottom stress is not strongly affected by the outer layer stratification. However, stratification reduces turbulent transport to the outer layer and strongly limits the boundary layer height. The mean shear at the top of the boundary layer is enhanced when the outer layer is stratified, and this shear is strong enough to cause intermittent instabilities above the pycnocline. Turbulence-generated internal gravity waves are observed in the outer layer with a relatively narrow frequency range. An explanation for frequency content of these waves is proposed, starting with an observed broad-banded turbulent spectrum and invoking linear viscous decay to explain the preferential damping of low and high frequency waves. During the course of this work, an open-source computational fluid dynamics code has been developed with a number of advanced features including scalar advection, subgrid-scale models for large-eddy simulation, and distributed memory

  9. E25 stratified torch ignition engine emissions and combustion analysis

    International Nuclear Information System (INIS)

    Rodrigues Filho, Fernando Antonio; Baêta, José Guilherme Coelho; Teixeira, Alysson Fernandes; Valle, Ramón Molina; Fonseca de Souza, José Leôncio

    2016-01-01

    Highlights: • A stratified torch ignition (STI) engine was built and tested. • The STI engines was tested in a wide range of load and speed. • Significant reduction on emissions was achieved by means of the STI system. • Low cyclic variability characterized the lean combustion process of the torch ignition engine. • HC emission is the main drawback of the stratified torch ignition engine. - Abstract: Vehicular emissions significantly increase atmospheric air pollution and greenhouse gases (GHG). This fact associated with fast global vehicle fleet growth calls for prompt scientific community technological solutions in order to promote a significant reduction in vehicle fuel consumption and emissions, especially of fossil fuels to comply with future legislation. To meet this goal, a prototype stratified torch ignition (STI) engine was built from a commercial existing baseline engine. In this system, combustion starts in a pre-combustion chamber, where the pressure increase pushes the combustion jet flames through calibrated nozzles to be precisely targeted into the main chamber. These combustion jet flames are endowed with high thermal and kinetic energy, being able to generate a stable lean combustion process. The high kinetic and thermal energy of the combustion jet flame results from the load stratification. This is carried out through direct fuel injection in the pre-combustion chamber by means of a prototype gasoline direct injector (GDI) developed for a very low fuel flow rate. In this work the engine out-emissions of CO, NOx, HC and CO_2 of the STI engine are presented and a detailed analysis supported by the combustion parameters is conducted. The results obtained in this work show a significant decrease in the specific emissions of CO, NOx and CO_2 of the STI engine in comparison with the baseline engine. On the other hand, HC specific emission increased due to wall wetting from the fuel hitting in the pre-combustion chamber wall.

  10. Direct contact condensation induced transition from stratified to slug flow

    International Nuclear Information System (INIS)

    Strubelj, Luka; Ezsoel, Gyoergy; Tiselj, Iztok

    2010-01-01

    Selected condensation-induced water hammer experiments performed on PMK-2 device were numerically modelled with three-dimensional two-fluid models of computer codes NEPTUNE C FD and CFX. Experimental setup consists of the horizontal pipe filled with the hot steam that is being slowly flooded with cold water. In most of the experimental cases, slow flooding of the pipe was abruptly interrupted by a strong slugging and water hammer, while in the selected experimental runs performed at higher initial pressures and temperatures that are analysed in the present work, the transition from the stratified into the slug flow was not accompanied by the water hammer pressure peak. That makes these cases more suitable tests for evaluation of the various condensation models in the horizontally stratified flows and puts them in the range of the available CFD (Computational Fluid Dynamics) codes. The key models for successful simulation appear to be the condensation model of the hot vapour on the cold liquid and the interfacial momentum transfer model. The surface renewal types of condensation correlations, developed for condensation in the stratified flows, were used in the simulations and were applied also in the regions of the slug flow. The 'large interface' model for inter-phase momentum transfer model was compared to the bubble drag model. The CFD simulations quantitatively captured the main phenomena of the experiments, while the stochastic nature of the particular condensation-induced water hammer experiments did not allow detailed prediction of the time and position of the slug formation in the pipe. We have clearly shown that even the selected experiments without water hammer present a tough test for the applied CFD codes, while modelling of the water hammer pressure peaks in two-phase flow, being a strongly compressible flow phenomena, is beyond the capability of the current CFD codes.

  11. Effects of unstratified and centre-stratified randomization in multi-centre clinical trials.

    Science.gov (United States)

    Anisimov, Vladimir V

    2011-01-01

    This paper deals with the analysis of randomization effects in multi-centre clinical trials. The two randomization schemes most often used in clinical trials are considered: unstratified and centre-stratified block-permuted randomization. The prediction of the number of patients randomized to different treatment arms in different regions during the recruitment period accounting for the stochastic nature of the recruitment and effects of multiple centres is investigated. A new analytic approach using a Poisson-gamma patient recruitment model (patients arrive at different centres according to Poisson processes with rates sampled from a gamma distributed population) and its further extensions is proposed. Closed-form expressions for corresponding distributions of the predicted number of the patients randomized in different regions are derived. In the case of two treatments, the properties of the total imbalance in the number of patients on treatment arms caused by using centre-stratified randomization are investigated and for a large number of centres a normal approximation of imbalance is proved. The impact of imbalance on the power of the study is considered. It is shown that the loss of statistical power is practically negligible and can be compensated by a minor increase in sample size. The influence of patient dropout is also investigated. The impact of randomization on predicted drug supply overage is discussed. Copyright © 2010 John Wiley & Sons, Ltd.

  12. Cotistas e não-cotistas: rendimento de alunos da Universidade de Brasília Quota and non-quota system: performance of students at University of Brasília

    Directory of Open Access Journals (Sweden)

    Jacques Velloso

    2009-08-01

    Full Text Available O texto discute o rendimento no curso de três turmas de alunos que ingressaram na Universidade de Brasília em 2004, 2005 e 2006, mediante vestibulares com dois sistemas de seleção, o de reserva de 20% das vagas para negros e o tradicional, de livre competição. Compararam-se as médias das notas de dois grupos de alunos em cada carreira, cotistas e não-cotistas, considerando o nível de prestígio social do curso e sua área do conhecimento do vestibular - Humanidades, Ciências e Saúde. Em linhas gerais, no conjunto das três turmas de cada área, os resultados mostraram que em aproximadamente dois terços ou mais das carreiras não houve diferenças expressivas entre as médias dos dois grupos ou estas foram favoráveis aos cotistas - apesar de exceção num único ano, nas Ciências. A principal tendência constatada, que encontrou eco em evidências empíricas de outras instituições, foi a da ausência de diferenças sistemáticas de rendimento a favor dos não-cotistas, contrariando previsões de críticos do sistema de cotas, no sentido de que este provocaria uma queda no padrão acadêmico da universidade.The text deals with the academic achievement of three cohorts of students who entered the University of Brasília in 2004, 2005 and 2006, by means of entrance exams involving two selection processes: a 20% quota for black students and traditional evaluation procedures. Achievement was measured by the average grades obtained in courses followed by two groups of students in each career, those from the quota system and those from the non-quota system. Careers were classified according to their social prestige and their areas in the entrance exams - Humanities, Sciences and Health. Broad data trends indicated that, for the three cohorts in all areas, in approximately two thirds (or more of the careers there were no meaningful differences between the average grades of the two groups, or these were favorable to students from the quota

  13. Technetium reduction and removal in a stratified fjord

    International Nuclear Information System (INIS)

    Keith-Roach, M.; Roos, P.

    2002-01-01

    The distribution of Tc in the water columns of a stratified fjord has been measured to investigate the behaviour and fate of Tc on reaching reducing waters. Slow mixing in the water column of the fjord results in vertical transport of the dissolved Tc to the oxic/anoxic interface. Tc is reduced just below the interface and at 21 m 60% is sorbed to particulate and colloidal material. Tc is carried to the sediments sorbed to the particulate material, where there is a current inventory of approximately 3 Bq m -2 . (LN)

  14. Stability of unstably stratified shear flow between parallel plates

    Energy Technology Data Exchange (ETDEWEB)

    Fujimura, Kaoru; Kelly, R E

    1987-09-01

    The linear stability of unstably stratified shear flows between two horizontal parallel plates was investigated. Eigenvalue problems were solved numerically by making use of the expansion method in Chebyshev polynomials, and the critical Rayleigh numbers were obtained accurately in the Reynolds number range of (0.01, 100). It was found that the critical Rayleigh number increases with an increase of the Reynolds number. The result strongly supports previous stability analyses except for the analysis by Makino and Ishikawa (J. Jpn. Soc. Fluid Mech. 4 (1985) 148 - 158) in which a decrease of the critical Rayleigh number was obtained.

  15. Stability of unstably stratified shear flow between parallel plates

    International Nuclear Information System (INIS)

    Fujimura, Kaoru; Kelly, R.E.

    1987-01-01

    The linear stability of unstably stratified shear flows between two horizontal parallel plates was investigated. Eigenvalue problems were solved numerically by making use of the expansion method in Chebyshev polynomials, and the critical Rayleigh numbers were obtained accurately in the Reynolds number range of [0.01, 100]. It was found that the critical Rayleigh number increases with an increase of the Reynolds number. The result strongly supports previous stability analyses except for the analysis by Makino and Ishikawa [J. Jpn. Soc. Fluid Mech. 4 (1985) 148 - 158] in which a decrease of the critical Rayleigh number was obtained. (author)

  16. Stratifying patients with peripheral neuropathic pain based on sensory profiles

    DEFF Research Database (Denmark)

    Vollert, Jan; Maier, Christoph; Attal, Nadine

    2017-01-01

    In a recent cluster analysis, it has been shown that patients with peripheral neuropathic pain can be grouped into 3 sensory phenotypes based on quantitative sensory testing profiles, which are mainly characterized by either sensory loss, intact sensory function and mild thermal hyperalgesia and...... populations that need to be screened to reach a subpopulation large enough to conduct a phenotype-stratified study. The most common phenotype in diabetic polyneuropathy was sensory loss (83%), followed by mechanical hyperalgesia (75%) and thermal hyperalgesia (34%, note that percentages are overlapping...

  17. Technetium reduction and removal in a stratified fjord

    Energy Technology Data Exchange (ETDEWEB)

    Keith-Roach, M.; Roos, P. [Risoe National Lab., Roskilde (Denmark)

    2002-04-01

    The distribution of Tc in the water columns of a stratified fjord has been measured to investigate the behaviour and fate of Tc on reaching reducing waters. Slow mixing in the water column of the fjord results in vertical transport of the dissolved Tc to the oxic/anoxic interface. Tc is reduced just below the interface and at 21 m 60% is sorbed to particulate and colloidal material. Tc is carried to the sediments sorbed to the particulate material, where there is a current inventory of approximately 3 Bq m{sup -2}. (LN)

  18. Development of a natural gas stratified charge rotary engine

    Energy Technology Data Exchange (ETDEWEB)

    Sierens, R.; Verdonck, W.

    1985-01-01

    A water model has been used to determine the positions of separate inlet ports for a natural gas, stratified charge rotary engine. The flow inside the combustion chamber (mainly during the induction period) has been registered by a film camera. From these tests the best locations of the inlet ports have been obtained, a prototype of this engine has been built by Audi NSU and tested in the laboratories of the university of Gent. The results of these tests, for different stratification configurations, are given. These results are comparable with the best results obtained by Audi NSU for a homogeneous natural gas rotary engine.

  19. SOLUTION OF A MULTIVARIATE STRATIFIED SAMPLING PROBLEM THROUGH CHEBYSHEV GOAL PROGRAMMING

    Directory of Open Access Journals (Sweden)

    Mohd. Vaseem Ismail

    2010-12-01

    Full Text Available In this paper, we consider the problem of minimizing the variances for the various characters with fixed (given budget. Each convex objective function is first linearised at its minimal point where it meets the linear cost constraint. The resulting multiobjective linear programming problem is then solved by Chebyshev goal programming. A numerical example is given to illustrate the procedure.

  20. Model-based estimation of finite population total in stratified sampling

    African Journals Online (AJOL)

    The work presented in this paper concerns the estimation of finite population total under model – based framework. Nonparametric regression approach as a method of estimating finite population total is explored. The asymptotic properties of the estimators based on nonparametric regression are also developed under ...

  1. ENVIRONMENTALLY STRATIFIED SAMPLING DESIGN FOR THE DEVELOPMENT OF THE GREAT LAKES ENVIRONMENTAL INDICATORS

    Science.gov (United States)

    Ecological indicators must be shown to be responsive to stress. For large-scale observational studies the best way to demonstrate responsiveness is by evaluating indicators along a gradient of stress, but such gradients are often unknown for a population of sites prior to site se...

  2. Crystallization of a compositionally stratified basal magma ocean

    Science.gov (United States)

    Laneuville, Matthieu; Hernlund, John; Labrosse, Stéphane; Guttenberg, Nicholas

    2018-03-01

    Earth's ∼3.45 billion year old magnetic field is regenerated by dynamo action in its convecting liquid metal outer core. However, convection induces an isentropic thermal gradient which, coupled with a high core thermal conductivity, results in rapid conducted heat loss. In the absence of implausibly high radioactivity or alternate sources of motion to drive the geodynamo, the Earth's early core had to be significantly hotter than the melting point of the lower mantle. While the existence of a dense convecting basal magma ocean (BMO) has been proposed to account for high early core temperatures, the requisite physical and chemical properties for a BMO remain controversial. Here we relax the assumption of a well-mixed convecting BMO and instead consider a BMO that is initially gravitationally stratified owing to processes such as mixing between metals and silicates at high temperatures in the core-mantle boundary region during Earth's accretion. Using coupled models of crystallization and heat transfer through a stratified BMO, we show that very high temperatures could have been trapped inside the early core, sequestering enough heat energy to run an ancient geodynamo on cooling power alone.

  3. Dyadic Green's function of an eccentrically stratified sphere.

    Science.gov (United States)

    Moneda, Angela P; Chrissoulidis, Dimitrios P

    2014-03-01

    The electric dyadic Green's function (dGf) of an eccentrically stratified sphere is built by use of the superposition principle, dyadic algebra, and the addition theorem of vector spherical harmonics. The end result of the analytical formulation is a set of linear equations for the unknown vector wave amplitudes of the dGf. The unknowns are calculated by truncation of the infinite sums and matrix inversion. The theory is exact, as no simplifying assumptions are required in any one of the analytical steps leading to the dGf, and it is general in the sense that any number, position, size, and electrical properties can be considered for the layers of the sphere. The point source can be placed outside of or in any lossless part of the sphere. Energy conservation, reciprocity, and other checks verify that the dGf is correct. A numerical application is made to a stratified sphere made of gold and glass, which operates as a lens.

  4. Crenothrix are major methane consumers in stratified lakes.

    Science.gov (United States)

    Oswald, Kirsten; Graf, Jon S; Littmann, Sten; Tienken, Daniela; Brand, Andreas; Wehrli, Bernhard; Albertsen, Mads; Daims, Holger; Wagner, Michael; Kuypers, Marcel Mm; Schubert, Carsten J; Milucka, Jana

    2017-09-01

    Methane-oxidizing bacteria represent a major biological sink for methane and are thus Earth's natural protection against this potent greenhouse gas. Here we show that in two stratified freshwater lakes a substantial part of upward-diffusing methane was oxidized by filamentous gamma-proteobacteria related to Crenothrix polyspora. These filamentous bacteria have been known as contaminants of drinking water supplies since 1870, but their role in the environmental methane removal has remained unclear. While oxidizing methane, these organisms were assigned an 'unusual' methane monooxygenase (MMO), which was only distantly related to 'classical' MMO of gamma-proteobacterial methanotrophs. We now correct this assignment and show that Crenothrix encode a typical gamma-proteobacterial PmoA. Stable isotope labeling in combination swith single-cell imaging mass spectrometry revealed methane-dependent growth of the lacustrine Crenothrix with oxygen as well as under oxygen-deficient conditions. Crenothrix genomes encoded pathways for the respiration of oxygen as well as for the reduction of nitrate to N 2 O. The observed abundance and planktonic growth of Crenothrix suggest that these methanotrophs can act as a relevant biological sink for methane in stratified lakes and should be considered in the context of environmental removal of methane.

  5. LONGITUDINAL OSCILLATIONS IN DENSITY STRATIFIED AND EXPANDING SOLAR WAVEGUIDES

    Energy Technology Data Exchange (ETDEWEB)

    Luna-Cardozo, M. [Instituto de Astronomia y Fisica del Espacio, CONICET-UBA, CC. 67, Suc. 28, 1428 Buenos Aires (Argentina); Verth, G. [School of Computing, Engineering and Information Sciences, Northumbria University, Newcastle Upon Tyne NE1 8ST (United Kingdom); Erdelyi, R., E-mail: mluna@iafe.uba.ar, E-mail: robertus@sheffield.ac.uk, E-mail: gary.verth@northumbria.ac.uk [Solar Physics and Space Plasma Research Centre (SP2RC), University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom)

    2012-04-01

    Waves and oscillations can provide vital information about the internal structure of waveguides in which they propagate. Here, we analytically investigate the effects of density and magnetic stratification on linear longitudinal magnetohydrodynamic (MHD) waves. The focus of this paper is to study the eigenmodes of these oscillations. It is our specific aim to understand what happens to these MHD waves generated in flux tubes with non-constant (e.g., expanding or magnetic bottle) cross-sectional area and density variations. The governing equation of the longitudinal mode is derived and solved analytically and numerically. In particular, the limit of the thin flux tube approximation is examined. The general solution describing the slow longitudinal MHD waves in an expanding magnetic flux tube with constant density is found. Longitudinal MHD waves in density stratified loops with constant magnetic field are also analyzed. From analytical solutions, the frequency ratio of the first overtone and fundamental mode is investigated in stratified waveguides. For small expansion, a linear dependence between the frequency ratio and the expansion factor is found. From numerical calculations it was found that the frequency ratio strongly depends on the density profile chosen and, in general, the numerical results are in agreement with the analytical results. The relevance of these results for solar magneto-seismology is discussed.

  6. Random forcing of geostrophic motion in rotating stratified turbulence

    Science.gov (United States)

    Waite, Michael L.

    2017-12-01

    Random forcing of geostrophic motion is a common approach in idealized simulations of rotating stratified turbulence. Such forcing represents the injection of energy into large-scale balanced motion, and the resulting breakdown of quasi-geostrophic turbulence into inertia-gravity waves and stratified turbulence can shed light on the turbulent cascade processes of the atmospheric mesoscale. White noise forcing is commonly employed, which excites all frequencies equally, including frequencies much higher than the natural frequencies of large-scale vortices. In this paper, the effects of these high frequencies in the forcing are investigated. Geostrophic motion is randomly forced with red noise over a range of decorrelation time scales τ, from a few time steps to twice the large-scale vortex time scale. It is found that short τ (i.e., nearly white noise) results in about 46% more gravity wave energy than longer τ, despite the fact that waves are not directly forced. We argue that this effect is due to wave-vortex interactions, through which the high frequencies in the forcing are able to excite waves at their natural frequencies. It is concluded that white noise forcing should be avoided, even if it is only applied to the geostrophic motion, when a careful investigation of spontaneous wave generation is needed.

  7. Improvements to TRAC models of condensing stratified flow. Pt. 1

    International Nuclear Information System (INIS)

    Zhang, Q.; Leslie, D.C.

    1991-12-01

    Direct contact condensation in stratified flow is an important phenomenon in LOCA analyses. In this report, the TRAC interfacial heat transfer model for stratified condensing flow has been assessed against the Bankoff experiments. A rectangular channel option has been added to the code to represent the experimental geometry. In almost all cases the TRAC heat transfer coefficient (HTC) over-predicts the condensation rates and in some cases it is so high that the predicted steam is sucked in from the normal outlet in order to conserve mass. Based on their cocurrent and countercurrent condensing flow experiments, Bankoff and his students (Lim 1981, Kim 1985) developed HTC models from the two cases. The replacement of the TRAC HTC with either of Bankoff's models greatly improves the predictions of condensation rates in the experiment with cocurrent condensing flow. However, the Bankoff HTC for countercurrent flow is preferable because it is based only on the local quantities rather than on the quantities averaged from the inlet. (author)

  8. Designing Wood Supply Scenarios from Forest Inventories with Stratified Predictions

    Directory of Open Access Journals (Sweden)

    Philipp Kilham

    2018-02-01

    Full Text Available Forest growth and wood supply projections are increasingly used to estimate the future availability of woody biomass and the correlated effects on forests and climate. This research parameterizes an inventory-based business-as-usual wood supply scenario, with a focus on southwest Germany and the period 2002–2012 with a stratified prediction. First, the Classification and Regression Trees algorithm groups the inventory plots into strata with corresponding harvest probabilities. Second, Random Forest algorithms generate individual harvest probabilities for the plots of each stratum. Third, the plots with the highest individual probabilities are selected as harvested until the harvest probability of the stratum is fulfilled. Fourth, the harvested volume of these plots is predicted with a linear regression model trained on harvested plots only. To illustrate the pros and cons of this method, it is compared to a direct harvested volume prediction with linear regression, and a combination of logistic regression and linear regression. Direct harvested volume regression predicts comparable volume figures, but generates these volumes in a way that differs from business-as-usual. The logistic model achieves higher overall classification accuracies, but results in underestimations or overestimations of harvest shares for several subsets of the data. The stratified prediction method balances this shortcoming, and can be of general use for forest growth and timber supply projections from large-scale forest inventories.

  9. Internal circle uplifts, transversality and stratified G-structures

    Energy Technology Data Exchange (ETDEWEB)

    Babalic, Elena Mirela [Department of Theoretical Physics, National Institute of Physics and Nuclear Engineering,Str. Reactorului no.30, P.O.BOX MG-6, Postcode 077125, Bucharest-Magurele (Romania); Department of Physics, University of Craiova,13 Al. I. Cuza Str., Craiova 200585 (Romania); Lazaroiu, Calin Iuliu [Center for Geometry and Physics, Institute for Basic Science,Pohang 790-784 (Korea, Republic of)

    2015-11-24

    We study stratified G-structures in N=2 compactifications of M-theory on eight-manifolds M using the uplift to the auxiliary nine-manifold M̂=M×S{sup 1}. We show that the cosmooth generalized distribution D̂ on M̂ which arises in this formalism may have pointwise transverse or non-transverse intersection with the pull-back of the tangent bundle of M, a fact which is responsible for the subtle relation between the spinor stabilizers arising on M and M̂ and for the complicated stratified G-structure on M which we uncovered in previous work. We give a direct explanation of the latter in terms of the former and relate explicitly the defining forms of the SU(2) structure which exists on the generic locus U of M to the defining forms of the SU(3) structure which exists on an open subset Û of M̂, thus providing a dictionary between the eight- and nine-dimensional formalisms.

  10. A modified stratified model for the 3C 273 jet

    International Nuclear Information System (INIS)

    Liu Wenpo; Shen Zhiqiang

    2009-01-01

    We present a modified stratified jet model to interpret the observed spectral energy distributions of knots in the 3C 273 jet. Based on the hypothesis of the single index of the particle energy spectrum at injection and identical emission processes among all the knots, the observed difference of spectral shape among different 3C 273 knots can be understood as a manifestation of the deviation of the equivalent Doppler factor of stratified emission regions in an individual knot from a characteristic one. The summed spectral energy distributions of all ten knots in the 3C 273 jet can be well fitted by two components: a low-energy component (radio to optical) dominated by synchrotron radiation and a high-energy component (UV, X-ray and γ-ray) dominated by inverse Compton scattering of the cosmic microwave background. This gives a consistent spectral index of α = 0.88 (S v ∝ v -α ) and a characteristic Doppler factor of 7.4. Assuming the average of the summed spectrum as the characteristic spectrum of each knot in the 3C 273 jet, we further get a distribution of Doppler factors. We discuss the possible implications of these results for the physical properties in the 3C 273 jet. Future GeV observations with GLAST could separate the γ-ray emission of 3C 273 from the large scale jet and the small scale jet (i.e. the core) through measuring the GeV spectrum.

  11. STRESS DISTRIBUTION IN THE STRATIFIED MASS CONTAINING VERTICAL ALVEOLE

    Directory of Open Access Journals (Sweden)

    Bobileva Tatiana Nikolaevna

    2017-08-01

    Full Text Available Almost all subsurface rocks used as foundations for various types of structures are stratified. Such heterogeneity may cause specific behaviour of the materials under strain. Differential equations describing the behaviour of such materials contain rapidly fluctuating coefficients, in view of this, solution of such equations is more time-consuming when using today’s computers. The method of asymptotic averaging leads to getting homogeneous medium under study to averaged equations with fixed factors. The present article is concerned with stratified soil mass consisting of pair-wise alternative isotropic elastic layers. In the results of elastic modules averaging, the present soil mass with horizontal rock stratification is simulated by homogeneous transversal-isotropic half-space with isotropy plane perpendicular to the standing axis. Half-space is loosened by a vertical alveole of circular cross-section, and virgin ground is under its own weight. For horizontal parting planes of layers, the following two types of surface conditions are set: ideal contact and backlash without cleavage. For homogeneous transversal-isotropic half-space received with a vertical alveole, the analytical solution of S.G. Lekhnitsky, well known in scientific papers, is used. The author gives expressions for stress components and displacements in soil mass for different marginal conditions on the alveole surface. Such research problems arise when constructing and maintaining buildings and when composite materials are used.

  12. Measuring mixing efficiency in experiments of strongly stratified turbulence

    Science.gov (United States)

    Augier, P.; Campagne, A.; Valran, T.; Calpe Linares, M.; Mohanan, A. V.; Micard, D.; Viboud, S.; Segalini, A.; Mordant, N.; Sommeria, J.; Lindborg, E.

    2017-12-01

    Oceanic and atmospheric models need better parameterization of the mixing efficiency. Therefore, we need to measure this quantity for flows representative of geophysical flows, both in terms of types of flows (with vortices and/or waves) and of dynamical regimes. In order to reach sufficiently large Reynolds number for strongly stratified flows, experiments for which salt is used to produce the stratification have to be carried out in a large rotating platform of at least 10-meter diameter.We present new experiments done in summer 2017 to study experimentally strongly stratified turbulence and mixing efficiency in the Coriolis platform. The flow is forced by a slow periodic movement of an array of large vertical or horizontal cylinders. The velocity field is measured by 3D-2C scanned horizontal particles image velocimetry (PIV) and 2D vertical PIV. Six density-temperature probes are used to measure vertical and horizontal profiles and signals at fixed positions.We will show how we rely heavily on open-science methods for this study. Our new results on the mixing efficiency will be presented and discussed in terms of mixing parameterization.

  13. Optimal energy growth in a stably stratified shear flow

    Science.gov (United States)

    Jose, Sharath; Roy, Anubhab; Bale, Rahul; Iyer, Krithika; Govindarajan, Rama

    2018-02-01

    Transient growth of perturbations by a linear non-modal evolution is studied here in a stably stratified bounded Couette flow. The density stratification is linear. Classical inviscid stability theory states that a parallel shear flow is stable to exponentially growing disturbances if the Richardson number (Ri) is greater than 1/4 everywhere in the flow. Experiments and numerical simulations at higher Ri show however that algebraically growing disturbances can lead to transient amplification. The complexity of a stably stratified shear flow stems from its ability to combine this transient amplification with propagating internal gravity waves (IGWs). The optimal perturbations associated with maximum energy amplification are numerically obtained at intermediate Reynolds numbers. It is shown that in this wall-bounded flow, the three-dimensional optimal perturbations are oblique, unlike in unstratified flow. A partitioning of energy into kinetic and potential helps in understanding the exchange of energies and how it modifies the transient growth. We show that the apportionment between potential and kinetic energy depends, in an interesting manner, on the Richardson number, and on time, as the transient growth proceeds from an optimal perturbation. The oft-quoted stabilizing role of stratification is also probed in the non-diffusive limit in the context of disturbance energy amplification.

  14. Application of first order rate kinetics to explain changes in bloom toxicity—the importance of understanding cell toxin quotas

    Science.gov (United States)

    Orr, Philip T.; Willis, Anusuya; Burford, Michele A.

    2018-04-01

    Cyanobacteria are oxygenic photosynthetic Gram-negative bacteria that can form potentially toxic blooms in eutrophic and slow flowing aquatic ecosystems. Bloom toxicity varies spatially and temporally, but understanding the mechanisms that drive these changes remains largely a mystery. Changes in bloom toxicity may result from changes in intracellular toxin pool sizes of cyanotoxins with differing molecular toxicities, and/or from changes in the cell concentrations of toxic and non-toxic cyanobacterial species or strains within bloom populations. We show here how first-order rate kinetics at the cellular level can be used to explain how environmental conditions drive changes in bloom toxicity at the ecological level. First order rate constants can be calculated for changes in cell concentration (μ c: specific cell division rate) or the volumetric biomass concentration (μ g: specific growth rate) between short time intervals throughout the cell cycle. Similar first order rate constants can be calculated for changes in nett volumetric cyanotoxin concentration (μ tox: specific cyanotoxin production rate) over similar time intervals. How μ c (or μ g ) covaries with μ tox over the cell cycle shows conclusively when cyanotoxins are being produced and metabolised, and how the toxicity of cells change in response to environment stressors. When μ tox/μ c>1, cyanotoxin cell quotas increase and individual cells become more toxic because the nett cyanotoxin production rate is higher than the cell division rate. When μ tox/μ c=1, cell cyanotoxin quotas remains fixed because the nett cyanotoxin production rate matches the cell division rate. When μ tox/μ ccyanotoxin cell quota decreases because either the nett cyanotoxin production rate is lower than the cell division rate, or metabolic breakdown and/or secretion of cyanotoxins is occurring. These fundamental equations describe cyanotoxin metabolism dynamics at the cellular level and provide the necessary

  15. Implications of the Abolition of Milk Quota System for Polish Agriculture – Simulation Results Based on the AG MEMOD Model

    Directory of Open Access Journals (Sweden)

    Mariusz Hamulczuk

    2009-09-01

    Full Text Available The objective of the study was to asses the economics effects of the dairy policy reform sanctioned by CAP Health Check on the agricultural market in Poland. The paper presents a theoretical study of the production control program as well as a model based quantitative analysis of the implications of the reform on the agricultural markets. The partial equilibrium model AGMEMOD was used for simulation. The results obtained indicate that the expansion and subsequently the elimination of milk quota system lead to the growth of milk production and consumption in Poland which confirms the hypothesis derived from theoretical study. As a consequence, the growth of the production of most of dairy products and the decrease of their prices is expected. As the growth of dairy consumption is smaller than the growth of milk production the increase of self-sufficiency in the dairy market is predicted. The comparison of the scale of price adjustment resulting from the dairy reform to the market price changes observed recently leads to the conclusion that global market factors will probably be more important for the future development of milk production and prices in Poland than the milk quota abolition. Nevertheless, the reform constitutes a significant change in business conditions for producers and consumers of milk and dairy products. As a consequence, milk production will become more market based, as far as market prices, production costs and milk yields are concerned. Simulation results from the AGMEMOD model confirm the opinion brought by other authors that the abolition of milk quotas will lead to the decline of dairy farmer income. The main beneficiaries of the reform would become the consumers who could take advantage of the decline in prices of the dairy products.

  16. Evaluating fishery rehabilitation under uncertainty: A bioeconomic analysis of quota management for the Green Bay yellow perch fishery

    Science.gov (United States)

    Johnson, B.L.; Milliman, S.R.; Bishop, R.C.; Kitchell, J.F.

    1992-01-01

    The fishery for yellow perch Perca flavescens in Green Bay, Lake Michigan, is currently operating under a rehabilitation plan based on a commercial harvest quota. We developed a bioeconomic computer model that included links between population density and growth, recruitment, and fishing effort for this fishery. Random variability was included in the stock-recruitment relation and in a simulated population assessment. We used the model in an adaptive management framework to evaluate the effects of the rehabilitation plan on both commercial and sport fisheries and to search for ways to improve the plan. Results indicate that the current quota policy is a member of a set of policies that would meet most management goals and increase total value of the fishery. Sensitivity analyses indicate that this conclusion is robust over a wide range of biological conditions. We predict that commercial fishers will lose money relative to the baseline condition, but they may receive other benefits from the elimination of the common-property nature of the fishery. The prospect exists for managing variability in harvest and stock size and for maximizing economic returns in the fishery, but more information is required, primarily on sportfishing effort dynamics and angler preferences. Stock-recruitment relations, density dependence of growth, and dynamics of sportfishing effort are the primary sources of uncertainty limiting the precision of our predictions. The current quota policy is about as good as other policies at reducing this uncertainty and appears, overall, to be one of the best choices for this fishery. The analytical techniques used in this study were primarily simple, heuristic approaches that could be easily transferred to other studies.

  17. Analysis of the System of Racial Quotas in Brazil as Affirmative Action Combined with the General Right to Equality

    Directory of Open Access Journals (Sweden)

    Alisson Magela Moreira Damasceno

    2016-10-01

    Full Text Available This article aims to discuss the system of racial quotas in Brazil, considering them as unequal treatment, which aims to promote equality. In the light of the thought of Alexy, it has been proposed to analyze the General Equality Law, to then justify the reasons for the unequal state treatment. Such unequal treatment in such cases will be addressed from the perspective of affirmative action. These measures are promoted in order to promote social redemption of company shares historically segregated. Thus, this study proposes an analysis of the general right to equality in the construction and application of the law.

  18. Reflection and transmission of electromagnetic waves in planarly stratified media

    International Nuclear Information System (INIS)

    Caviglia, G.

    1999-01-01

    Propagation of time-harmonic electromagnetic waves in planarly stratified multilayers is investigated. Each layer is allowed to be inhomogeneous and the layers are separated by interfaces. The procedure is based on the representation of the electromagnetic field in the basis of the eigenvectors of the matrix characterizing the first-order system. Hence the local reflection and transmission matrices are defined and the corresponding differential equations, in the pertinent space variable are determined. The jump conditions at interfaces are also established. The present model incorporates dissipative materials and the procedure holds without any restrictions to material symmetries. Differential equations appeared in the literature are shown to hold in particular (one-dimensional) cases or to represent homogeneous layers only

  19. Microstructure of Turbulence in the Stably Stratified Boundary Layer

    Science.gov (United States)

    Sorbjan, Zbigniew; Balsley, Ben B.

    2008-11-01

    The microstructure of a stably stratified boundary layer, with a significant low-level nocturnal jet, is investigated based on observations from the CASES-99 campaign in Kansas, U.S.A. The reported, high-resolution vertical profiles of the temperature, wind speed, wind direction, pressure, and the turbulent dissipation rate, were collected under nocturnal conditions on October 14, 1999, using the CIRES Tethered Lifting System. Two methods for evaluating instantaneous (1-sec) background profiles are applied to the raw data. The background potential temperature is calculated using the “bubble sort” algorithm to produce a monotonically increasing potential temperature with increasing height. Other scalar quantities are smoothed using a running vertical average. The behaviour of background flow, buoyant overturns, turbulent fluctuations, and their respective histograms are presented. Ratios of the considered length scales and the Ozmidov scale are nearly constant with height, a fact that can be applied in practice for estimating instantaneous profiles of the dissipation rate.

  20. Hydrodynamics of stratified epithelium: Steady state and linearized dynamics

    Science.gov (United States)

    Yeh, Wei-Ting; Chen, Hsuan-Yi

    2016-05-01

    A theoretical model for stratified epithelium is presented. The viscoelastic properties of the tissue are assumed to be dependent on the spatial distribution of proliferative and differentiated cells. Based on this assumption, a hydrodynamic description of tissue dynamics at the long-wavelength, long-time limit is developed, and the analysis reveals important insights into the dynamics of an epithelium close to its steady state. When the proliferative cells occupy a thin region close to the basal membrane, the relaxation rate towards the steady state is enhanced by cell division and cell apoptosis. On the other hand, when the region where proliferative cells reside becomes sufficiently thick, a flow induced by cell apoptosis close to the apical surface enhances small perturbations. This destabilizing mechanism is general for continuous self-renewal multilayered tissues; it could be related to the origin of certain tissue morphology, tumor growth, and the development pattern.

  1. A study of stratified gas-liquid pipe flow

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, George W.

    2005-07-01

    This work includes both theoretical modelling and experimental observations which are relevant to the design of gas condensate transport lines. Multicomponent hydrocarbon gas mixtures are transported in pipes over long distances and at various inclinations. Under certain circumstances, the heavier hydrocarbon components and/or water vapour condense to form one or more liquid phases. Near the desired capacity, the liquid condensate and water is efficiently transported in the form of a stratified flow with a droplet field. During operating conditions however, the flow rate may be reduced allowing liquid accumulation which can create serious operational problems due to large amounts of excess liquid being expelled into the receiving facilities during production ramp-up or even in steady production in severe cases. In particular, liquid tends to accumulate in upward inclined sections due to insufficient drag on the liquid from the gas. To optimize the transport of gas condensates, a pipe diameters should be carefully chosen to account for varying flow rates and pressure levels which are determined through the knowledge of the multiphase flow present. It is desirable to have a reliable numerical simulation tool to predict liquid accumulation for various flow rates, pipe diameters and pressure levels which is not presently accounted for by industrial flow codes. A critical feature of the simulation code would include the ability to predict the transition from small liquid accumulation at high flow rates to large liquid accumulation at low flow rates. A semi-intermittent flow regime of roll waves alternating with a partly backward flowing liquid film has been observed experimentally to occur for a range of gas flow rates. Most of the liquid is transported in the roll waves. The roll wave regime is not well understood and requires fundamental modelling and experimental research. The lack of reliable models for this regime leads to inaccurate prediction of the onset of

  2. Hydromagnetic stability of rotating stratified compressible fluid flows

    Energy Technology Data Exchange (ETDEWEB)

    Srinivasan, V; Kandaswamy, P [Dept. of Mathematics, Bharathiar University, Coimbatore, Tamil Nadu, India; Debnath, L [Dept. of Mathematics, University of Central Florida, Orlando, USA

    1984-09-01

    The hydromagnetic stability of a radially stratified compressible fluid rotating between two coaxial cylinders is investigated. The stability with respect to axisymmetric disturbances is examined. The fluid system is found to be thoroughly stable to axisymmetric disturbances provided the fluid rotates very rapidly. The system is shown to be unstable to non-axisymmetric disturbances, and the slow amplifying hydromagnetic wave modes propagate against the basic rotation. The lower and upper bounds of the azimuthal phase speeds of the amplifying waves are determined. A quadrant theorem on the slow waves characteristic of a rapidly rotating fluid is derived. Special attention is given to the effects of compressibility of the fluid. Some results concerning the stability of an incompressible fluid system are obtained as special cases of the present analysis.

  3. The Risk-Stratified Osteoporosis Strategy Evaluation study (ROSE)

    DEFF Research Database (Denmark)

    Rubin, Katrine Hass; Holmberg, Teresa; Rothmann, Mette Juel

    2015-01-01

    The risk-stratified osteoporosis strategy evaluation study (ROSE) is a randomized prospective population-based study investigating the effectiveness of a two-step screening program for osteoporosis in women. This paper reports the study design and baseline characteristics of the study population....... 35,000 women aged 65-80 years were selected at random from the population in the Region of Southern Denmark and-before inclusion-randomized to either a screening group or a control group. As first step, a self-administered questionnaire regarding risk factors for osteoporosis based on FRAX......(®) was issued to both groups. As second step, subjects in the screening group with a 10-year probability of major osteoporotic fractures ≥15 % were offered a DXA scan. Patients diagnosed with osteoporosis from the DXA scan were advised to see their GP and discuss pharmaceutical treatment according to Danish...

  4. Direct numerical simulation of homogeneous stratified rotating turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Iida, O.; Tsujimura, S.; Nagano, Y. [Nagoya Institute of Technology, Department of Mech. Eng., Nagoya (Japan)

    2005-12-01

    The effects of the Prandtl number on stratified rotating turbulence have been studied in homogeneous turbulence by using direct numerical simulations and a rapid distortion theory. Fluctuations under strong stable-density stratification can be theoretically divided into the WAVE and the potential vorticity (PV) modes. In low-Prandtl-number fluids, the WAVE mode deteriorates, while the PV mode remains. Imposing rotation on a low-Prandtl-number fluid makes turbulence two-dimensional as well as geostrophic; it is found from the instantaneous turbulent structure that the vortices merge to form a few vertically-elongated vortex columns. During the period toward two-dimensionalization, the vertical vortices become asymmetric in the sense of rotation. (orig.)

  5. Advanced stratified charge rotary aircraft engine design study

    Science.gov (United States)

    Badgley, P.; Berkowitz, M.; Jones, C.; Myers, D.; Norwood, E.; Pratt, W. B.; Ellis, D. R.; Huggins, G.; Mueller, A.; Hembrey, J. H.

    1982-01-01

    A technology base of new developments which offered potential benefits to a general aviation engine was compiled and ranked. Using design approaches selected from the ranked list, conceptual design studies were performed of an advanced and a highly advanced engine sized to provide 186/250 shaft Kw/HP under cruise conditions at 7620/25,000 m/ft altitude. These are turbocharged, direct-injected stratified charge engines intended for commercial introduction in the early 1990's. The engine descriptive data includes tables, curves, and drawings depicting configuration, performance, weights and sizes, heat rejection, ignition and fuel injection system descriptions, maintenance requirements, and scaling data for varying power. An engine-airframe integration study of the resulting engines in advanced airframes was performed on a comparative basis with current production type engines. The results show airplane performance, costs, noise & installation factors. The rotary-engined airplanes display substantial improvements over the baseline, including 30 to 35% lower fuel usage.

  6. Internal combustion engine using premixed combustion of stratified charges

    Science.gov (United States)

    Marriott, Craig D [Rochester Hills, MI; Reitz, Rolf D [Madison, WI

    2003-12-30

    During a combustion cycle, a first stoichiometrically lean fuel charge is injected well prior to top dead center, preferably during the intake stroke. This first fuel charge is substantially mixed with the combustion chamber air during subsequent motion of the piston towards top dead center. A subsequent fuel charge is then injected prior to top dead center to create a stratified, locally richer mixture (but still leaner than stoichiometric) within the combustion chamber. The locally rich region within the combustion chamber has sufficient fuel density to autoignite, and its self-ignition serves to activate ignition for the lean mixture existing within the remainder of the combustion chamber. Because the mixture within the combustion chamber is overall premixed and relatively lean, NO.sub.x and soot production are significantly diminished.

  7. Visualization periodic flows in a continuously stratified fluid.

    Science.gov (United States)

    Bardakov, R.; Vasiliev, A.

    2012-04-01

    To visualize the flow pattern of viscous continuously stratified fluid both experimental and computational methods were developed. Computational procedures were based on exact solutions of set of the fundamental equations. Solutions of the problems of flows producing by periodically oscillating disk (linear and torsion oscillations) were visualized with a high resolutions to distinguish small-scale the singular components on the background of strong internal waves. Numerical algorithm of visualization allows to represent both the scalar and vector fields, such as velocity, density, pressure, vorticity, stream function. The size of the source, buoyancy and oscillation frequency, kinematic viscosity of the medium effects were traced in 2D an 3D posing problems. Precision schlieren instrument was used to visualize the flow pattern produced by linear and torsion oscillations of strip and disk in a continuously stratified fluid. Uniform stratification was created by the continuous displacement method. The buoyancy period ranged from 7.5 to 14 s. In the experiments disks with diameters from 9 to 30 cm and a thickness of 1 mm to 10 mm were used. Different schlieren methods that are conventional vertical slit - Foucault knife, vertical slit - filament (Maksoutov's method) and horizontal slit - horizontal grating (natural "rainbow" schlieren method) help to produce supplementing flow patterns. Both internal wave beams and fine flow components were visualized in vicinity and far from the source. Intensity of high gradient envelopes increased proportionally the amplitude of the source. In domains of envelopes convergence isolated small scale vortices and extended mushroom like jets were formed. Experiments have shown that in the case of torsion oscillations pattern of currents is more complicated than in case of forced linear oscillations. Comparison with known theoretical model shows that nonlinear interactions between the regular and singular flow components must be taken

  8. Longevity of Compositionally Stratified Layers in Ice Giants

    Science.gov (United States)

    Friedson, A. J.

    2017-12-01

    In the hydrogen-rich atmospheres of gas giants, a decrease with radius in the mixing ratio of a heavy species (e.g. He, CH4, H2O) has the potential to produce a density stratification that is convectively stable if the heavy species is sufficiently abundant. Formation of stable layers in the interiors of these planets has important implications for their internal structure, chemical mixing, dynamics, and thermal evolution, since vertical transport of heat and constituents in such layers is greatly reduced in comparison to that in convecting layers. Various processes have been suggested for creating compositionally stratified layers. In the interiors of Jupiter and Saturn, these include phase separation of He from metallic hydrogen and dissolution of dense core material into the surrounding metallic-H envelope. Condensation of methane and water has been proposed as a mechanism for producing stable zones in the atmospheres of Saturn and the ice giants. However, if a stably stratified layer is formed adjacent to an active region of convection, it may be susceptible to progressive erosion as the convection intrudes and entrains fluid into the unstable envelope. We discuss the principal factors that control the rate of entrainment and associated erosion and present a specific example concerning the longevity of stable layers formed by condensation of methane and water in Uranus and Neptune. We also consider whether the temporal variability of such layers may engender episodic behavior in the release of the internal heat of these planets. This research is supported by a grant from the NASA Solar System Workings Program.

  9. Investigations on flow reversal in stratified horizontal flow

    International Nuclear Information System (INIS)

    Staebler, T.; Meyer, L.; Schulenberg, T.; Laurien, E.

    2005-01-01

    The phenomena of flow reversal in stratified flows are investigated in a horizontal channel with application to the Emergency Core Cooling System (ECCS) in Pressurized Water Reactors (PWR). In case of a Loss-of-Coolant-Accident (LOCA), coolant can be injected through a secondary pipe within the feeding line of the primary circuit, the so called hot leg, counter-currently to the steam flow. It is essential that the coolant reaches the reactor core to prevent overheating. Due to high temperatures in such accident scenarios, steam is generated in the core, which escapes from the reactor vessel through the hot leg. In case of sufficiently high steam flow rates, only a reduced amount of coolant or even no coolant will be delivered to the reactor core. The WENKA test facility at the Institute for Nuclear and Energy Technologies (IKET) at Forschungszentrum Karlsruhe is capable to investigate the fluid dynamics of two-phase flows in such scenarios. Water and air flow counter-currently in a horizontal channel made of clear acrylic glass to allow full optical access. Flow rates of water and air can be varied independently within a wide range. Once flow reversal sets in, a strong hysteresis effect must be taken into account. This was quantified during the present investigations. Local experimental data are needed to expand appropriate models on flow reversal in horizontal two-phase flow and to include them into numerical codes. Investigations are carried out by means of Particle Image Velocimetry (PIV) to obtain local flow velocities without disturbing the flow. Due to the wavy character of the flow, strong reflections at the interfacial area must be taken into account. Using fluorescent particles and an optical filter allows eliminating the reflections and recording only the signals of the particles. The challenges in conducting local investigations in stratified wavy flows by applying optical measurement techniques are discussed. Results are presented and discussed allowing

  10. Stratified flow model for convective condensation in an inclined tube

    International Nuclear Information System (INIS)

    Lips, Stéphane; Meyer, Josua P.

    2012-01-01

    Highlights: ► Convective condensation in an inclined tube is modelled. ► The heat transfer coefficient is the highest for about 20° below the horizontal. ► Capillary forces have a strong effect on the liquid–vapour interface shape. ► A good agreement between the model and the experimental results was observed. - Abstract: Experimental data are reported for condensation of R134a in an 8.38 mm inner diameter smooth tube in inclined orientations with a mass flux of 200 kg/m 2 s. Under these conditions, the flow is stratified and there is an optimum inclination angle, which leads to the highest heat transfer coefficient. There is a need for a model to better understand and predict the flow behaviour. In this paper, the state of the art of existing models of stratified two-phase flows in inclined tubes is presented, whereafter a new mechanistic model is proposed. The liquid–vapour distribution in the tube is determined by taking into account the gravitational and the capillary forces. The comparison between the experimental data and the model prediction showed a good agreement in terms of heat transfer coefficients and pressure drops. The effect of the interface curvature on the heat transfer coefficient has been quantified and has been found to be significant. The optimum inclination angle is due to a balance between an increase of the void fraction and an increase in the falling liquid film thickness when the tube is inclined downwards. The effect of the mass flux and the vapour quality on the optimum inclination angle has also been studied.

  11. Stakeholder analysis. Report no. 1: Companies' overall strategies and evaluation of the effect of quota regulation; Aktoeranalysen. Repport nr. 1: Virksomhedernes overordnede strategier og vurdering af betyningen af kvotereguleringen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-03-15

    The overall aim of the project was to determine what effect the energy policy introduced through the law on CO{sub 2}-quotas would have on the development the energy sector in Denmark. The energy policy is a market-based approach where the individual stakeholders choose how they will react within the boundaries of the allocated quotas. Options include the purchasing of quotas on the open market, investment in CDM/JI activities, the implementation of energy efficiency initiatives or fuel substitution. The focus of the study was on how the affected companies reacted to the implementation of a CO{sub 2}-quota. This was done by undertaking a series of interviews that resulted in a stakeholder analysis of companies encompassed by the CO2-quota law. A series of national consequences of the law on CO{sub 2}-quotas were then determined based on the stakeholder analysis. According to the results of the stakeholder analysis the following consequences were determined for the periods 2005-2007 and 2008-2012 as a result of quota regulation: 1) In the electricity sector no additional investments will be made in energy efficiency initiatives or fuel substitution projects than were already planned before quota regulation was introduced. 2) The heating sector will carry out isolated energy efficiency projects, but generally these are not socio-economically viable. 3) Industry will carry out isolated energy efficiency initiatives and renewable energy projects. Only 1.2 million tonnes of CO2 will be reduced annually through these initiatives compared to the estimated annual shortfall of 8 13 million tonnes CO{sub 2}. The shortfall will be made up through the purchase of quotas on the open market. This study indicates, therefore, that quota regulation will make a limited contribution to further initiatives in energy efficiency and renewable energy. If further energy efficiency initiatives are desired it will be necessary to implement other regulatory incentives. With regards to the

  12. Mobilifilum chasei: morphology and ecology of a spirochete from an intertidal stratified microbial mat community

    Science.gov (United States)

    Margulis, L.; Hinkle, G.; Stolz, J.; Craft, F.; Esteve, I.; Guerrero, R.

    1990-01-01

    Spirochetes were found in the lower anoxiphototrophic layer of a stratified microbial mat (North Pond, Laguna Figueroa, Baja California, Mexico). Ultra-structural analysis of thin sections of field samples revealed spirochetes approximately 0.25 micrometer in diameter with 10 or more periplasmic flagella, leading to the interpretation that these spirochetes bear 10 flagellar insertions on each end. Morphometric study showed these free-living spirochetes greatly resemble certain symbiotic ones, i.e., Borrelia and certain termite spirochetes, the transverse sections of which are presented here. The ultrastructure of this spirochete also resembles Hollandina and Diplocalyx (spirochetes symbiotic in arthropods) more than it does Spirochaeta, the well known genus of mud-dwelling spirochetes. The new spirochete was detected in mat material collected both in 1985 and in 1987. Unique morphology (i.e., conspicuous outer coat of inner membrane, large number of periplasmic flagella) and ecology prompt us to name a new free-living spirochete.

  13. Stratified flows with variable density: mathematical modelling and numerical challenges.

    Science.gov (United States)

    Murillo, Javier; Navas-Montilla, Adrian

    2017-04-01

    Stratified flows appear in a wide variety of fundamental problems in hydrological and geophysical sciences. They may involve from hyperconcentrated floods carrying sediment causing collapse, landslides and debris flows, to suspended material in turbidity currents where turbulence is a key process. Also, in stratified flows variable horizontal density is present. Depending on the case, density varies according to the volumetric concentration of different components or species that can represent transported or suspended materials or soluble substances. Multilayer approaches based on the shallow water equations provide suitable models but are not free from difficulties when moving to the numerical resolution of the governing equations. Considering the variety of temporal and spatial scales, transfer of mass and energy among layers may strongly differ from one case to another. As a consequence, in order to provide accurate solutions, very high order methods of proved quality are demanded. Under these complex scenarios it is necessary to observe that the numerical solution provides the expected order of accuracy but also converges to the physically based solution, which is not an easy task. To this purpose, this work will focus in the use of Energy balanced augmented solvers, in particular, the Augmented Roe Flux ADER scheme. References: J. Murillo , P. García-Navarro, Wave Riemann description of friction terms in unsteady shallow flows: Application to water and mud/debris floods. J. Comput. Phys. 231 (2012) 1963-2001. J. Murillo B. Latorre, P. García-Navarro. A Riemann solver for unsteady computation of 2D shallow flows with variable density. J. Comput. Phys.231 (2012) 4775-4807. A. Navas-Montilla, J. Murillo, Energy balanced numerical schemes with very high order. The Augmented Roe Flux ADER scheme. Application to the shallow water equations, J. Comput. Phys. 290 (2015) 188-218. A. Navas-Montilla, J. Murillo, Asymptotically and exactly energy balanced augmented flux

  14. Deep silicon maxima in the stratified oligotrophic Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    Y. Crombet

    2011-02-01

    Full Text Available The silicon biogeochemical cycle has been studied in the Mediterranean Sea during late summer/early autumn 1999 and summer 2008. The distribution of nutrients, particulate carbon and silicon, fucoxanthin (Fuco, and total chlorophyll-a (TChl-a were investigated along an eastward gradient of oligotrophy during two cruises (PROSOPE and BOUM encompassing the entire Mediterranean Sea during the stratified period. At both seasons, surface waters were depleted in nutrients and the nutriclines gradually deepened towards the East, the phosphacline being the deepest in the easternmost Levantine basin. Following the nutriclines, parallel deep maxima of biogenic silica (DSM, fucoxanthin (DFM and TChl-a (DCM were evidenced during both seasons with maximal concentrations of 0.45 μmol L−1 for BSi, 0.26 μg L−1 for Fuco, and 1.70 μg L−1 for TChl-a, all measured during summer. Contrary to the DCM which was a persistent feature in the Mediterranean Sea, the DSM and DFMs were observed in discrete areas of the Alboran Sea, the Algero-Provencal basin, the Ionian sea and the Levantine basin, indicating that diatoms were able to grow at depth and dominate the DCM under specific conditions. Diatom assemblages were dominated by Chaetoceros spp., Leptocylindrus spp., Pseudonitzschia spp. and the association between large centric diatoms (Hemiaulus hauckii and Rhizosolenia styliformis and the cyanobacterium Richelia intracellularis was observed at nearly all sites. The diatom's ability to grow at depth is commonly observed in other oligotrophic regions and could play a major role in ecosystem productivity and carbon export to depth. Contrary to the common view that Si and siliceous phytoplankton are not major components of the Mediterranean biogeochemistry, we suggest here that diatoms, by persisting at depth during the stratified period, could contribute to a

  15. Experimental CFD grade data for stratified two-phase flows

    Energy Technology Data Exchange (ETDEWEB)

    Vallee, Christophe, E-mail: c.vallee@fzd.d [Forschungszentrum Dresden-Rossendorf e.V., Institute of Safety Research, D-01314 Dresden (Germany); Lucas, Dirk; Beyer, Matthias; Pietruske, Heiko; Schuetz, Peter; Carl, Helmar [Forschungszentrum Dresden-Rossendorf e.V., Institute of Safety Research, D-01314 Dresden (Germany)

    2010-09-15

    Stratified two-phase flows were investigated at two test facilities with horizontal test-sections. For both, rectangular channel cross-sections were chosen to provide optimal observation possibilities for the application of optical measurement techniques. In order to show the local flow structure, high-speed video observation was applied, which delivers the high-resolution in space and time needed for CFD code validation. The first investigations were performed in the Horizontal Air/Water Channel (HAWAC), which is made of acrylic glass and allows the investigation of air/water co-current flows at atmospheric pressure and room temperature. At the channel inlet, a special device was designed for well-defined and adjustable inlet boundary conditions. For the quantitative analysis of the optical measurements performed at the HAWAC, an algorithm was developed to recognise the stratified interface in the camera frames. This allows to make statistical treatments for comparison with CFD calculation results. As an example, the unstable wave growth leading to slug flow is shown from the test-section inlet. Moreover, the hydraulic jump as the quasi-stationary discontinuous transition between super- and subcritical flow was investigated in this closed channel. The structure of the hydraulic jump over time is revealed by the calculation of the probability density of the water level. A series of experiments show that the hydraulic jump profile and its position from the inlet vary substantially with the inlet boundary conditions due to the momentum exchange between the phases. The second channel is built in the pressure chamber of the TOPFLOW test facility, which is used to perform air/water and steam/water experiments at pressures of up to 5.0 MPa and temperatures of up to 264 {sup o}C, but under pressure equilibrium with the vessel inside. In the present experiment, the test-section represents a flat model of the hot leg of the German Konvoi pressurised water reactor scaled at

  16. Experimental CFD grade data for stratified two-phase flows

    International Nuclear Information System (INIS)

    Vallee, Christophe; Lucas, Dirk; Beyer, Matthias; Pietruske, Heiko; Schuetz, Peter; Carl, Helmar

    2010-01-01

    Stratified two-phase flows were investigated at two test facilities with horizontal test-sections. For both, rectangular channel cross-sections were chosen to provide optimal observation possibilities for the application of optical measurement techniques. In order to show the local flow structure, high-speed video observation was applied, which delivers the high-resolution in space and time needed for CFD code validation. The first investigations were performed in the Horizontal Air/Water Channel (HAWAC), which is made of acrylic glass and allows the investigation of air/water co-current flows at atmospheric pressure and room temperature. At the channel inlet, a special device was designed for well-defined and adjustable inlet boundary conditions. For the quantitative analysis of the optical measurements performed at the HAWAC, an algorithm was developed to recognise the stratified interface in the camera frames. This allows to make statistical treatments for comparison with CFD calculation results. As an example, the unstable wave growth leading to slug flow is shown from the test-section inlet. Moreover, the hydraulic jump as the quasi-stationary discontinuous transition between super- and subcritical flow was investigated in this closed channel. The structure of the hydraulic jump over time is revealed by the calculation of the probability density of the water level. A series of experiments show that the hydraulic jump profile and its position from the inlet vary substantially with the inlet boundary conditions due to the momentum exchange between the phases. The second channel is built in the pressure chamber of the TOPFLOW test facility, which is used to perform air/water and steam/water experiments at pressures of up to 5.0 MPa and temperatures of up to 264 o C, but under pressure equilibrium with the vessel inside. In the present experiment, the test-section represents a flat model of the hot leg of the German Konvoi pressurised water reactor scaled at 1

  17. Plume Splitting in a Two-layer Stratified Ambient Fluid

    Science.gov (United States)

    Ma, Yongxing; Flynn, Morris; Sutherland, Bruce

    2017-11-01

    A line-source plume descending into a two-layer stratified ambient fluid in a finite sized tank is studied experimentally. Although the total volume of ambient fluid is fixed, lower- and upper-layer fluids are respectively removed and added at a constant rate mimicking marine outfall through diffusers and natural and hybrid ventilated buildings. The influence of the plume on the ambient depends on the value of λ, defined as the ratio of the plume buoyancy to the buoyancy loss of the plume as it crosses the ambient interface. Similar to classical filling-box experiments, the plume can always reach the bottom of the tank if λ > 1 . By contrast, if λ < 1 , an intermediate layer eventually forms as a result of plume splitting. Eventually all of the plume fluid spreads within the intermediate layer. The starting time, tv, and the ending time, tt, of the transition process measured from experiments correlate with the value of λ. A three-layer ambient fluid is observed after transition, and the mean value of the measured densities of the intermediate layer fluid is well predicted using plume theory. Acknowledgments: Funding for this study was provided by NSERC.

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

    Directory of Open Access Journals (Sweden)

    Hans-Joerg eFugel

    2016-05-01

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

  19. Operations and Maintenance Cost for Stratified Buildings: A Critical Review

    Directory of Open Access Journals (Sweden)

    Che-Ghani Nor Zaimah

    2016-01-01

    Full Text Available Building maintenance is essential in preserving buildings’ appearance and performance. It needs to upkeep the building performance to prolong its value and building life cycle. Malaysia is still lacking in managing cost for building operation and maintenance. It has been found that the cost for housing maintenance is high due to poor maintenance practices. In order to get better understanding on how to manage the cost, this study reviews the contributing factors that affecting operation and maintenance cost of stratified buildings in Malaysia. The research first identified the factors through extensive literature review and scrutinize on factors that affecting and can minimize operation and maintenance cost. This literature review offers insight into building maintenance scenario in Malaysia focusing on the issues and challenges. The study also finds that operation and maintenance cost for housing in Malaysia is still in poor state. Interestingly, this paper revealed that operation and maintenance cost is also influenced by three significant factors like expectation of tenants, building characteristics and building defects. Measures to reduce the housing operation and maintenance cost are also highlighted so that this study can be a stepping stone towards proposing efficient and effective facilities management strategies for affordable housing in future.

  20. Stratified patterns of divorce: Earnings, education, and gender

    Directory of Open Access Journals (Sweden)

    Amit Kaplan

    2015-05-01

    Full Text Available Background: Despite evidence that divorce has become more prevalent among weaker socioeconomic groups, knowledge about the stratification aspects of divorce in Israel is lacking. Moreover, although scholarly debate recognizes the importance of stratificational positions with respect to divorce, less attention has been given to the interactions between them. Objective: Our aim is to examine the relationship between social inequality and divorce, focusing on how household income, education, employment stability, relative earnings, and the intersection between them affect the risk of divorce in Israel. Methods: The data is derived from combined census files for 1995-2008, annual administrative employment records from the National Insurance Institute and the Tax Authority, and data from the Civil Registry of Divorce. We used a series of discrete-time event-history analysis models for marital dissolution. Results: Couples in lower socioeconomic positions had a higher risk of divorce in Israel. Higher education in general, and homogamy in terms of higher education (both spouses have degrees in particular, decreased the risk of divorce. The wife's relative earnings had a differential effect on the likelihood of divorce, depending on household income: a wife who outearned her husband increased the log odds of divorce more in the upper tertiles than in the lower tertile. Conclusions: Our study shows that divorce indeed has a stratified pattern and that weaker socioeconomic groups experience the highest levels of divorce. Gender inequality within couples intersects with the household's economic and educational resources.

  1. Clinical research in small genomically stratified patient populations.

    Science.gov (United States)

    Martin-Liberal, J; Rodon, J

    2017-07-01

    The paradigm of early drug development in cancer is shifting from 'histology-oriented' to 'molecularly oriented' clinical trials. This change can be attributed to the vast amount of tumour biology knowledge generated by large international research initiatives such as The Cancer Genome Atlas (TCGA) and the use of next generation sequencing (NGS) techniques developed in recent years. However, targeting infrequent molecular alterations entails a series of special challenges. The optimal molecular profiling method, the lack of standardised biological thresholds, inter- and intra-tumor heterogeneity, availability of enough tumour material, correct clinical trials design, attrition rate, logistics or costs are only some of the issues that need to be taken into consideration in clinical research in small genomically stratified patient populations. This article examines the most relevant challenges inherent to clinical research in these populations. Moreover, perspectives from the Academia point of view are reviewed as well as initiatives to be taken in forthcoming years. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Stratifying the Risk of Venous Thromboembolism in Otolaryngology

    Science.gov (United States)

    Shuman, Andrew G.; Hu, Hsou Mei; Pannucci, Christopher J.; Jackson, Christopher R.; Bradford, Carol R.; Bahl, Vinita

    2015-01-01

    Objective The consequences of perioperative venous thromboembolism (VTE) are devastating; identifying patients at risk is an essential step in reducing morbidity and mortality. The utility of perioperative VTE risk assessment in otolaryngology is unknown. This study was designed to risk-stratify a diverse population of otolaryngology patients for VTE events. Study Design Retrospective cohort study. Setting Single-institution academic tertiary care medical center. Subjects and Methods Adult patients presenting for otolaryngologic surgery requiring hospital admission from 2003 to 2010 who did not receive VTE chemoprophylaxis were included. The Caprini risk assessment was retrospectively scored via a validated method of electronic chart abstraction. Primary study variables were Caprini risk scores and the incidence of perioperative venous thromboembolic outcomes. Results A total of 2016 patients were identified. The overall 30-day rate of VTE was 1.3%. The incidence of VTE in patients with a Caprini risk score of 6 or less was 0.5%. For patients with scores of 7 or 8, the incidence was 2.4%. Patients with a Caprini risk score greater than 8 had an 18.3% incidence of VTE and were significantly more likely to develop a VTE when compared to patients with a Caprini risk score less than 8 (P otolaryngology patients for 30-day VTE events and allows otolaryngologists to identify patient subgroups who have a higher risk of VTE in the absence of chemoprophylaxis. PMID:22261490

  3. Stratified charge rotary engine critical technology enablement. Volume 2: Appendixes

    Science.gov (United States)

    Irion, C. E.; Mount, R. E.

    1992-01-01

    This second volume of appendixes is a companion to Volume 1 of this report which summarizes results of a critical technology enablement effort with the stratified charge rotary engine (SCRE) focusing on a power section of 0.67 liters (40 cu. in.) per rotor in single and two rotor versions. The work is a continuation of prior NASA Contracts NAS3-23056 and NAS3-24628. Technical objectives are multi-fuel capability, including civil and military jet fuel and DF-2, fuel efficiency of 0.355 Lbs/BHP-Hr. at best cruise condition above 50 percent power, altitude capability of up to 10Km (33,000 ft.) cruise, 2000 hour TBO and reduced coolant heat rejection. Critical technologies for SCRE's that have the potential for competitive performance and cost in a representative light-aircraft environment were examined. Objectives were: the development and utilization of advanced analytical tools, i.e. higher speed and enhanced three dimensional combustion modeling; identification of critical technologies; development of improved instrumentation; and to isolate and quantitatively identify the contribution to performance and efficiency of critical components or subsystems. A family of four-stage third-order explicit Runge-Kutta schemes is derived that required only two locations and has desirable stability characteristics. Error control is achieved by embedding a second-order scheme within the four-stage procedure. Certain schemes are identified that are as efficient and accurate as conventional embedded schemes of comparable order and require fewer storage locations.

  4. Stratified Charge Rotary Engine Critical Technology Enablement, Volume 1

    Science.gov (United States)

    Irion, C. E.; Mount, R. E.

    1992-01-01

    This report summarizes results of a critical technology enablement effort with the stratified charge rotary engine (SCRE) focusing on a power section of 0.67 liters (40 cu. in.) per rotor in single and two rotor versions. The work is a continuation of prior NASA Contracts NAS3-23056 and NAS3-24628. Technical objectives are multi-fuel capability, including civil and military jet fuel and DF-2, fuel efficiency of 0.355 Lbs/BHP-Hr. at best cruise condition above 50 percent power, altitude capability of up to 10Km (33,000 ft.) cruise, 2000 hour TBO and reduced coolant heat rejection. Critical technologies for SCRE's that have the potential for competitive performance and cost in a representative light-aircraft environment were examined. Objectives were: the development and utilization of advanced analytical tools, i.e. higher speed and enhanced three dimensional combustion modeling; identification of critical technologies; development of improved instrumentation, and to isolate and quantitatively identify the contribution to performance and efficiency of critical components or subsystems.

  5. Layer contributions to the nonlinear acoustic radiation from stratified media.

    Science.gov (United States)

    Vander Meulen, François; Haumesser, Lionel

    2016-12-01

    This study presents the thorough investigation of the second harmonic generation scenario in a three fluid layer system. An emphasis is on the evaluation of the nonlinear parameter B/A in each layer from remote measurements. A theoretical approach of the propagation of a finite amplitude acoustic wave in a multilayered medium is developed. In the frame of the KZK equation, the weak nonlinearity of the media, attenuation and diffraction effects are computed for the fundamental and second harmonic waves propagating back and forth in each of the layers of the system. The model uses a gaussian expansion to describe the beam propagation in order to quantitatively evaluate the contribution of each part of the system (layers and interfaces) to its nonlinearity. The model is validated through measurements on a water/aluminum/water system. Transmission as well as reflection configurations are studied. Good agreement is found between the theoretical results and the experimental data. The analysis of the second harmonic field sources measured by the transducers from outside the stratified medium highlights the factors that favor the cumulative effects. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Local properties of countercurrent stratified steam-water flow

    International Nuclear Information System (INIS)

    Kim, H.J.

    1985-10-01

    A study of steam condensation in countercurrent stratified flow of steam and subcooled water has been carried out in a rectangular channel/flat plate geometry over a wide range of inclination angles (4 0 -87 0 ) at several aspect ratios. Variables were inlet water and steam flow rates, and inlet water temperature. Local condensation rates and pressure gradients were measured, and local condensation heat transfer coefficients and interfacial shear stress were calculated. Contact probe traverses of the surface waves were made, which allowed a statistical analysis of the wave properties. The local condensation Nusselt number was correlated in terms of local water and steam Reynolds or Froude numbers, as well as the liquid Prandtl number. A turbulence-centered model developed by Theofanous, et al. principally for gas absorption in several geometries, was modified. A correlation for the interfacial shear stress and the pressure gradient agreed with measured values. Mean water layer thicknesses were calculated. Interfacial wave parameters, such as the mean water layer thickness, liquid fraction probability distribution, wave amplitude and wave frequency, are analyzed

  7. Long-term forecasting of sales of the products of a company in International markets of enriched uranium under restrictions and quotas

    International Nuclear Information System (INIS)

    Klimanov, S.G.; Kryanev, A.V.; Rostovskij, N.S.; Sliva, D.E.; Smirnov, D.S.; Kharitonov, V.V.

    2016-01-01

    A technique of forecasting company sales in the international regional markets of enriched uranium under imposed restrictions and quotas has been developed by the authors on the basis on scenario forecasts of the demand for company products and has been implemented as a set of computer software [ru

  8. Microcystin quota, cell division and microcystin net production of precultured Microcystis aeruginosa CYA 228 (Chroococcales, Cyanophyceae) under field conditions

    DEFF Research Database (Denmark)

    Lyck, S.; Christoffersen, K.

    2003-01-01

    compared with previous data obtained from batch cultures. Growth of an easily recognizable unicellular culture alga in the field made it possible to evaluate different ways of expressing mcyst field data as the ratio of mcyst to dry weight, protein or chlorophyll a (Chl a) against the mcyst quota...

  9. 78 FR 56646 - Determination of Total Amounts of Fiscal Year 2014 WTO Tariff-Rate Quotas for Raw Cane Sugar and...

    Science.gov (United States)

    2013-09-13

    ... Secretary Determination of Total Amounts of Fiscal Year 2014 WTO Tariff- Rate Quotas for Raw Cane Sugar and Certain Sugars, Syrups and Molasses AGENCY: Office of the Secretary, USDA. ACTION: Notice. SUMMARY: The... sugar at 1,117,195 metric tons raw value (MTRV). The Secretary also announces the establishment of the...

  10. Inclusion in higher education: trajetórias acadêmicas of students with disabilities that entered state university in rio grande south by quota system

    Directory of Open Access Journals (Sweden)

    Marilú Mourão Pereira

    2008-12-01

    Full Text Available This work intends to present the results of research done in the State University of Rio Grande do Sul, where he sought to analyze the academic trajectory of students with disabilities, who joined the system of quotas in the period from 2002 to 2005. This study aimed at understanding the process of implementation of quotas from affirmative action in higher education, as a possible contribution to the inclusion of students with disabilities at the University. The methodological approach was kind of qualitative and instruments used. In addition to students with disabilities, this study was to subject some managers who were involved with the subject at the University. The study was developed from the identification and characterization of pupils who joined the university by quota systems, followed by research and analysis of the trajectories of students with disabilities, for access and during the course. We interviewed 16 students with physical disabilities, hearing and vision, and ten managers of the University. The deployment of the system of quotas for students with disabilities, this is a University as a political action and democratization of access to higher education and is in line with the Constitutional principles, guaranteeing the rights of Persons with Disabilities. This, however, has not been enough to ensure the permanence of such students at the University. The results show the occurrence of difficulties which are concentrated in the process of teaching and learning need specific actions, directed to that portion of the population academic.

  11. Energy taxes in practice. Energy tax - electricity tax - biofuel quota - energy tax compliance. 3. upd. and rev. ed.

    International Nuclear Information System (INIS)

    Stein, Roland M.; Thoms, Anahita

    2016-01-01

    You need a quick and easy overview of the legal provisions of the energy tax law? You would like to understand the relationship between the European and national regulations and their impact on the daily practice? This manual prepares the energy tax, electricity tax and biofuel quota law for you clearly on and illustrated by examples, what to look in practice in order to avoid pitfalls. It picks up especially contentious issues and problems, discusses the relevant case law and the relevant regulations and finally gives precise recommendations for daily practice. Based on practice notes, examples and diagrams you can easily identify how to transfer the legal requirements on the own workspaces or optionally can use tax breaks. This includes information on both simplified - and thus less subject to error - methods and to tax exemptions and credits. The manual is complemented by forms, extracts from the Combined Nomenclature and an online material collection with regulatory and legal texts. [de

  12. Second law characterization of stratified thermal storage tanks

    Energy Technology Data Exchange (ETDEWEB)

    Fraidenraich, N [Departamento de Energia Nuclear-UFPE (Brazil)

    2000-07-01

    It is well known that fluid stratification in thermal storage tanks improves the overall performance of solar thermal systems, when compared with systems operating with uniform fluid temperature. From the point of view of the first law of thermodynamics, no difference exists between storage tanks with the same mass and average temperature, even if they have different stratified thermal structures. Nevertheless, the useful thermal energy that can be obtained from them might differ significantly. In this work, we derive an expression able to characterize the stratified configuration of thermal fluid. Using results obtained by thermodynamics of irreversible processes, the procedure adopted consists in calculating the maximum work available from the tank's thermal layer is able to develop. We arrive, then, at a dimensionless expression, the stratification parameter (SP), which depends on the mass fraction and absolute temperature of each thermal layer as well as the thermal fluid average temperature. Numerical examples for different types of tank stratification are given and it is verified that the expression obtained is sensitive to small differences in the reservoir thermal configuration. For example a thermal storage with temperatures equal to 74 Celsius degrees, 64 Celsius degrees and 54 Celsius degrees, with its mass equally distributed along the tank yields, for the parameter SP, a figure equal to 0.000294. On the other hand a storage tank with the same average temperature but with different layer's temperatures 76 Celsius degrees, 64 and 52 Celsius degrees, also with uniform mass distribution, yields for SP a value equal to quantitative evaluation of the stratification structure of thermal reservoirs. [Spanish] Es bien conocido que la estratificacion fluida en tanques de almacenamiento termico mejora el rendimiento total de los sistemas termicos solares en comparacion con sistemas que operan con temperatura uniforme del fluido. Desde el punto de vista

  13. Mahalanobis' Contributions to Sample Surveys

    Indian Academy of Sciences (India)

    Sample Survey started its operations in October 1950 under the ... and adopted random cuts for estimating the acreage under jute ... demographic factors relating to indebtedness, unemployment, ... traffic surveys, demand for currency coins and average life of .... Mahalanobis derived the optimum allocation in stratified.

  14. Internal and vorticity waves in decaying stratified flows

    Science.gov (United States)

    Matulka, A.; Cano, D.

    2009-04-01

    Most predictive models fail when forcing at the Rossby deformation Radius is important and a large range of scales have to be taken into account. When mixing of reactants or pollutants has to be accounted, the range of scales spans from hundreds of Kilometers to the Bachelor or Kolmogorov sub milimiter scales. We present some theoretical arguments to describe the flow in terms of the three dimensional vorticity equations, using a lengthscale related to the vorticity (or enstrophy ) transport. Effect of intermittent eddies and non-homogeneity of diffusion are also key issues in the environment because both stratification and rotation body forces are important and cause anisotropy/non-homogeneity. These problems need further theoretical, numerical and observational work and one approach is to try to maximize the relevant geometrical information in order to understand and therefore predict these complex environmental dispersive flows. The importance of the study of turbulence structure and its relevance in diffusion of contaminants in environmental flows is clear when we see the effect of environmental disasters such as the Prestige oil spill or the Chernobil radioactive cloud spread in the atmosphere. A series of Experiments have been performed on a strongly stratified two layer fluid consisting of Brine in the bottom and freshwater above in a 1 square meter tank. The evolution of the vortices after the passage of a grid is video recorded and Particle tracking is applied on small pliolite particles floating at the interface. The combination of internal waves and vertical vorticity produces two separate time scales that may produce resonances. The vorticity is seen to oscilate in a complex way, where the frecuency decreases with time.

  15. Tumour vasculature immaturity, oxidative damage and systemic inflammation stratify survival of colorectal cancer patients on bevacizumab treatment

    Science.gov (United States)

    Martin, Petra; Biniecka, Monika; Ó'Meachair, Shane; Maguire, Aoife; Tosetto, Miriam; Nolan, Blathnaid; Hyland, John; Sheahan, Kieran; O'Donoghue, Diarmuid; Mulcahy, Hugh; Fennelly, David; O'Sullivan, Jacintha

    2018-01-01

    Despite treatment of patients with metastatic colorectal cancer (mCRC) with bevacizumab plus chemotherapy, response rates are modest and there are no biomarkers available that will predict response. The aim of this study was to assess if markers associated with three interconnected cancer-associated biological processes, specifically angiogenesis, inflammation and oxidative damage, could stratify the survival outcome of this cohort. Levels of angiogenesis, inflammation and oxidative damage markers were assessed in pre-bevacizumab resected tumour and serum samples of mCRC patients by dual immunofluorescence, immunohistochemistry and ELISA. This study identified that specific markers of angiogenesis, inflammation and oxidative damage stratify survival of patients on this anti-angiogenic treatment. Biomarkers of immature tumour vasculature (% IMM, p=0.026, n=80), high levels of oxidative damage in the tumour epithelium (intensity of 8-oxo-dG in nuclear and cytoplasmic compartments, p=0.042 and 0.038 respectively, n=75) and lower systemic pro-inflammatory cytokines (IL6 and IL8, p=0.053 and 0.049 respectively, n=61) significantly stratify with median overall survival (OS). In summary, screening for a panel of biomarkers for high levels of immature tumour vasculature, high levels of oxidative DNA damage and low levels of systemic pro-inflammatory cytokines may be beneficial in predicting enhanced survival outcome following bevacizumab treatment for mCRC. PMID:29535825

  16. Using the Internet to Support Exercise and Diet: A Stratified Norwegian Survey.

    Science.gov (United States)

    Wangberg, Silje C; Sørensen, Tove; Andreassen, Hege K

    2015-08-26

    Internet is used for a variety of health related purposes. Use differs and has differential effects on health according to socioeconomic status. We investigated to what extent the Norwegian population use the Internet to support exercise and diet, what kind of services they use, and whether there are social disparities in use. We expected to find differences according to educational attainment. In November 2013 we surveyed a stratified sample of 2196 persons drawn from a Web panel of about 50,000 Norwegians over 15 years of age. The questionnaire included questions about using the Internet, including social network sites (SNS), or mobile apps in relation to exercise or diet, as well as background information about education, body image, and health. The survey email was opened by 1187 respondents (54%). Of these, 89 did not click on the survey hyperlink (declined to participate), while another 70 did not complete the survey. The final sample size is thus 1028 (87% response rate). Compared to the Norwegian census the sample had a slight under-representation of respondents under the age of 30 and with low education. The data was weighted accordingly before analyses. Sixty-nine percent of women and 53% of men had read about exercise or diet on the Internet (χ(2)= 25.6, Psocial disparities in health, and continue to monitor population use. For Internet- and mobile-based interventions to support health behaviors, this study provides information relevant to tailoring of delivery media and components to user.

  17. Zooplankton structure and vertical migration: Using acoustics and biomass to compare stratified and mixed fjord systems

    Science.gov (United States)

    Díaz-Astudillo, Macarena; Cáceres, Mario A.; Landaeta, Mauricio F.

    2017-09-01

    The patterns of abundance, composition, biomass and vertical migration of zooplankton in short-time scales (ADCP device mounted on the hull of a ship were used to obtain vertical profiles of current velocity data and intensity of the backscattered acoustic signal, which was used to study the migratory strategies and to relate the echo intensity with zooplankton biomass. Repeated vertical profiles of temperature, salinity and density were obtained with a CTD instrument to describe the density patterns during both experiments. Zooplankton were sampled every 3 h using a Bongo net to determine abundance, composition and biomass. Migrations were diel in the stratified station, semi-diel in the mixed station, and controlled by light in both locations, with large and significant differences in zooplankton abundance and biomass between day and night samples. No migration pattern associated with the effect of tides was found. The depth of maximum backscatter strength showed differences of approximately 30 m between stations and was deeper in the mixed station. The relation between mean volume backscattering strength (dB) computed from echo intensity and log10 of total dry weight (mg m-3) of zooplankton biomass was moderate but significant in both locations. Biomass estimated from biological samples was higher in the mixed station and determined by euphausiids. Copepods were the most abundant group in both stations. Acoustic methods were a useful technique to understand the detailed patterns of migratory strategies of zooplankton and to help estimate zooplankton biomass and abundance in the inner waters of southern Chile.

  18. Towards Cost-efficient Sampling Methods

    OpenAIRE

    Peng, Luo; Yongli, Li; Chong, Wu

    2014-01-01

    The sampling method has been paid much attention in the field of complex network in general and statistical physics in particular. This paper presents two new sampling methods based on the perspective that a small part of vertices with high node degree can possess the most structure information of a network. The two proposed sampling methods are efficient in sampling the nodes with high degree. The first new sampling method is improved on the basis of the stratified random sampling method and...

  19. Experimental Validation of a Domestic Stratified Hot Water Tank Model in Modelica for Annual Performance Assessment

    DEFF Research Database (Denmark)

    Carmo, Carolina; Dumont, Olivier; Nielsen, Mads Pagh

    2015-01-01

    The use of stratified hot water tanks in solar energy systems - including ORC systems - as well as heat pump systems is paramount for a better performance of these systems. However, the availability of effective and reliable models to predict the annual performance of stratified hot water tanks...

  20. Properties of the endogenous post-stratified estimator using a random forests model

    Science.gov (United States)

    John Tipton; Jean Opsomer; Gretchen G. Moisen

    2012-01-01

    Post-stratification is used in survey statistics as a method to improve variance estimates. In traditional post-stratification methods, the variable on which the data is being stratified must be known at the population level. In many cases this is not possible, but it is possible to use a model to predict values using covariates, and then stratify on these predicted...

  1. Implementing content constraints in alpha-stratified adaptive testing using a shadow test approach

    NARCIS (Netherlands)

    van der Linden, Willem J.; Chang, Hua-Hua

    2001-01-01

    The methods of alpha-stratified adaptive testing and constrained adaptive testing with shadow tests are combined in this study. The advantages are twofold. First, application of the shadow test allows the researcher to implement any type of constraint on item selection in alpha-stratified adaptive

  2. Stratified turbulent Bunsen flames : flame surface analysis and flame surface density modelling

    NARCIS (Netherlands)

    Ramaekers, W.J.S.; Oijen, van J.A.; Goey, de L.P.H.

    2012-01-01

    In this paper it is investigated whether the Flame Surface Density (FSD) model, developed for turbulent premixed combustion, is also applicable to stratified flames. Direct Numerical Simulations (DNS) of turbulent stratified Bunsen flames have been carried out, using the Flamelet Generated Manifold

  3. Turbulence Statistics of a Buoyant Jet in a Stratified Environment

    Science.gov (United States)

    McCleney, Amy Brooke

    Using non-intrusive optical diagnostics, turbulence statistics for a round, incompressible, buoyant, and vertical jet discharging freely into a stably linear stratified environment is studied and compared to a reference case of a neutrally buoyant jet in a uniform environment. This is part of a validation campaign for computational fluid dynamics (CFD). Buoyancy forces are known to significantly affect the jet evolution in a stratified environment. Despite their ubiquity in numerous natural and man-made flows, available data in these jets are limited, which constrain our understanding of the underlying physical processes. In particular, there is a dearth of velocity field data, which makes it challenging to validate numerical codes, currently used for modeling these important flows. Herein, jet near- and far-field behaviors are obtained with a combination of planar laser induced fluorescence (PLIF) and multi-scale time-resolved particle image velocimetry (TR-PIV) for Reynolds number up to 20,000. Deploying non-intrusive optical diagnostics in a variable density environment is challenging in liquids. The refractive index is strongly affected by the density, which introduces optical aberrations and occlusions that prevent the resolution of the flow. One solution consists of using index matched fluids with different densities. Here a pair of water solutions - isopropanol and NaCl - are identified that satisfy these requirements. In fact, they provide a density difference up to 5%, which is the largest reported for such fluid pairs. Additionally, by design, the kinematic viscosities of the solutions are identical. This greatly simplifies the analysis and subsequent simulations of the data. The spectral and temperature dependence of the solutions are fully characterized. In the near-field, shear layer roll-up is analyzed and characterized as a function of initial velocity profile. In the far-field, turbulence statistics are reported for two different scales, one

  4. Thermal stratification built up in hot water tank with different inlet stratifiers

    DEFF Research Database (Denmark)

    Dragsted, Janne; Furbo, Simon; Dannemand, Mark

    2017-01-01

    Thermal stratification in a water storage tank can strongly increase the thermal performance of solar heating systems. Thermal stratification can be built up in a storage tank during charge, if the heated water enters through an inlet stratifier. Experiments with a test tank have been carried out...... in order to elucidate how well thermal stratification is established in the tank with differently designed inlet stratifiers under different controlled laboratory conditions. The investigated inlet stratifiers are from Solvis GmbH & Co KG and EyeCular Technologies ApS. The inlet stratifier from Solvis Gmb...... for Solvis GmbH & Co KG had a better performance at 4 l/min. In the intermediate charge test the stratifier from EyeCular Technologies ApS had a better performance in terms of maintaining the thermal stratification in the storage tank while charging with a relative low temperature. [All rights reserved...

  5. Exploring the salivary microbiome of children stratified by the oral hygiene index

    Science.gov (United States)

    Mashima, Izumi; Theodorea, Citra F.; Thaweboon, Boonyanit; Thaweboon, Sroisiri; Scannapieco, Frank A.

    2017-01-01

    Poor oral hygiene often leads to chronic diseases such as periodontitis and dental caries resulting in substantial economic costs and diminished quality of life in not only adults but also in children. In this study, the salivary microbiome was characterized in a group of children stratified by the Simplified Oral Hygiene Index (OHI-S). Illumina MiSeq high-throughput sequencing based on the 16S rRNA was utilized to analyze 90 salivary samples (24 Good, 31 Moderate and 35 Poor oral hygiene) from a cohort of Thai children. A total of 38,521 OTUs (Operational Taxonomic Units) with a 97% similarity were characterized in all of the salivary samples. Twenty taxonomic groups (Seventeen genera, two families and one class; Streptococcus, Veillonella, Gemellaceae, Prevotella, Rothia, Porphyromonas, Granulicatella, Actinomyces, TM-7-3, Leptotrichia, Haemophilus, Selenomonas, Neisseria, Megasphaera, Capnocytophaga, Oribacterium, Abiotrophia, Lachnospiraceae, Peptostreptococcus, and Atopobium) were found in all subjects and constituted 94.5–96.5% of the microbiome. Of these twenty genera, the proportion of Streptococcus decreased while Veillonella increased with poor oral hygiene status (P oral hygiene group. This is the first study demonstrating an important association between increase of Veillonella and poor oral hygiene status in children. However, further studies are required to identify the majority of Veillonella at species level in salivary microbiome of the Poor oral hygiene group. PMID:28934367

  6. Characterisation of the suspended particulate matter in a stratified estuarine environment employing complementary techniques

    Science.gov (United States)

    Thomas, Luis P.; Marino, Beatriz M.; Szupiany, Ricardo N.; Gallo, Marcos N.

    2017-09-01

    The ability to predict the sediment and nutrient circulation within estuarine waters is of significant economic and ecological importance. In these complex systems, flocculation is a dynamically active process that is directly affected by the prevalent environmental conditions. Consequently, the floc properties continuously change, which greatly complicates the characterisation of the suspended particle matter (SPM). In the present study, three different techniques are combined in a stratified estuary under quiet weather conditions and with a low river discharge to search for a solution to this problem. The challenge is to obtain the concentration, size and flux of suspended elements through selected cross-sections using the method based on the simultaneous backscatter records of 1200 and 600 kHz ADCPs, isokinetic sampling data and LISST-25X measurements. The two-ADCP method is highly effective for determining the SPM size distributions in a non-intrusive way. The isokinetic sampling and the LISST-25X diffractometer offer point measurements at specific depths, which are especially useful for calibrating the ADCP backscatter intensity as a function of the SPM concentration and size, and providing complementary information on the sites where acoustic records are not available. Limitations and potentials of the techniques applied are discussed.

  7. Yield and quality of ground water from stratified-drift aquifers, Taunton River basin, Massachusetts : executive summary

    Science.gov (United States)

    Lapham, Wayne W.; Olimpio, Julio C.

    1989-01-01

    Water shortages are a chronic problem in parts of the Taunton River basin and are caused by a combination of factors. Water use in this part of the Boston metropolitan area is likely to increase during the next decade. The Massachusetts Division of Water Resources projects that about 50% of the cities and towns within and on the perimeter of the basin may have water supply deficits by 1990 if water management projects are not pursued throughout the 1980s. Estimates of the long-term yield of the 26 regional aquifers indicate that the yields of the two most productive aquifers equal or exceed 11.9 and 11.3 cu ft/sec, 90% of the time, respectively, if minimum stream discharge is maintained at 99.5% flow duration. Eighteen of the 26 aquifers were pumped for public water supply during 1983. Further analysis of the yield characteristics of these 18 aquifers indicates that the 1983 pumping rate of each of these 18 aquifers can be sustained at least 70% of the time. Selected physical properties and concentrations of major chemical constituents in groundwater from the stratified-drift aquifers at 80 sampling sites were used to characterize general water quality in aquifers throughout the basin. The pH of the groundwater ranged from 5.4 to 7.0. Natural elevated concentrations of Fe and Mn in water in the stratified-drift aquifers are present locally in the basin. Natural concentrations of these two metals commonly exceed the limits of 0.3 mg/L for Fe and 0.05 mg/L for Mn recommended for drinking water. Fifty-one analyses of selected trace metals in groundwater samples from stratified-drift aquifers throughout the basin were used to characterize trace metal concentrations in the groundwater. Of the 10 constituents sampled that have US EPA limits recommended for drinking water, only the Pb concentration in water at one site (60 micrograms/L) exceeded the recommended limit of 50 micrograms/L. Analyses of selected organic compounds in water in the stratified-drift aquifers at 74

  8. Indications for tonsillectomy stratified by the level of evidence

    Science.gov (United States)

    Windfuhr, Jochen P.

    2016-01-01

    Background: One of the most significant clinical trials, demonstrating the efficacy of tonsillectomy (TE) for recurrent throat infection in severely affected children, was published in 1984. This systematic review was undertaken to compile various indications for TE as suggested in the literature after 1984 and to stratify the papers according to the current concept of evidence-based medicine. Material and methods: A systematic Medline research was performed using the key word of “tonsillectomy“ in combination with different filters such as “systematic reviews“, “meta-analysis“, “English“, “German“, and “from 1984/01/01 to 2015/05/31“. Further research was performed in the Cochrane Database of Systematic Reviews, National Guideline Clearinghouse, Guidelines International Network and BMJ Clinical Evidence using the same key word. Finally, data from the “Trip Database” were researched for “tonsillectomy” and “indication“ and “from: 1984 to: 2015“ in combination with either “systematic review“ or “meta-analysis“ or “metaanalysis”. Results: A total of 237 papers were retrieved but only 57 matched our inclusion criteria covering the following topics: peritonsillar abscess (3), guidelines (5), otitis media with effusion (5), psoriasis (3), PFAPA syndrome (6), evidence-based indications (5), renal diseases (7), sleep-related breathing disorders (11), and tonsillitis/pharyngitis (12), respectively. Conclusions: 1) The literature suggests, that TE is not indicated to treat otitis media with effusion. 2) It has been shown, that the PFAPA syndrome is self-limiting and responds well to steroid administration, at least in a considerable amount of children. The indication for TE therefore appears to be imbalanced but further research is required to clarify the value of surgery. 3) Abscesstonsillectomy as a routine is not justified and indicated only for cases not responding to other measures of treatment, evident complications

  9. Methylmercury speciation in the dissolved phase of a stratified lake using the diffusive gradient in thin film technique

    Energy Technology Data Exchange (ETDEWEB)

    Clarisse, Olivier [Trent University, Department of Chemistry, 1600 West Bank Drive, Peterborough, Ontario K9J 7B8 (Canada)], E-mail: olivier.clarisse@umoncton.ca; Foucher, Delphine; Hintelmann, Holger [Trent University, Department of Chemistry, 1600 West Bank Drive, Peterborough, Ontario K9J 7B8 (Canada)

    2009-03-15

    The diffusive gradient in thin film (DGT) technique was successfully used to monitor methylmercury (MeHg) speciation in the dissolved phase of a stratified boreal lake, Lake 658 of the Experimental Lakes Area (ELA) in Ontario, Canada. Water samples were conventionally analysed for MeHg, sulfides, and dissolved organic matter (DOM). MeHg accumulated by DGT devices was compared to MeHg concentration measured conventionally in water samples to establish MeHg speciation. In the epilimnion, MeHg was almost entirely bound to DOM. In the top of the hypolimnion an additional labile fraction was identified, and at the bottom of the lake a significant fraction of MeHg was potentially associated to colloidal material. As part of the METAALICUS project, isotope enriched inorganic mercury was applied to Lake 658 and its watershed for several years to establish the relationship between atmospheric Hg deposition and Hg in fish. Little or no difference in MeHg speciation in the dissolved phase was detected between ambient and spike MeHg. - Methylmercury speciation was determined in the dissolved phase of a stratified lake using the diffusive gradient in thin film technique.

  10. Methylmercury speciation in the dissolved phase of a stratified lake using the diffusive gradient in thin film technique

    International Nuclear Information System (INIS)

    Clarisse, Olivier; Foucher, Delphine; Hintelmann, Holger

    2009-01-01

    The diffusive gradient in thin film (DGT) technique was successfully used to monitor methylmercury (MeHg) speciation in the dissolved phase of a stratified boreal lake, Lake 658 of the Experimental Lakes Area (ELA) in Ontario, Canada. Water samples were conventionally analysed for MeHg, sulfides, and dissolved organic matter (DOM). MeHg accumulated by DGT devices was compared to MeHg concentration measured conventionally in water samples to establish MeHg speciation. In the epilimnion, MeHg was almost entirely bound to DOM. In the top of the hypolimnion an additional labile fraction was identified, and at the bottom of the lake a significant fraction of MeHg was potentially associated to colloidal material. As part of the METAALICUS project, isotope enriched inorganic mercury was applied to Lake 658 and its watershed for several years to establish the relationship between atmospheric Hg deposition and Hg in fish. Little or no difference in MeHg speciation in the dissolved phase was detected between ambient and spike MeHg. - Methylmercury speciation was determined in the dissolved phase of a stratified lake using the diffusive gradient in thin film technique

  11. Health service accreditation as a predictor of clinical and organisational performance: a blinded, random, stratified study.

    Science.gov (United States)

    Braithwaite, Jeffrey; Greenfield, David; Westbrook, Johanna; Pawsey, Marjorie; Westbrook, Mary; Gibberd, Robert; Naylor, Justine; Nathan, Sally; Robinson, Maureen; Runciman, Bill; Jackson, Margaret; Travaglia, Joanne; Johnston, Brian; Yen, Desmond; McDonald, Heather; Low, Lena; Redman, Sally; Johnson, Betty; Corbett, Angus; Hennessy, Darlene; Clark, John; Lancaster, Judie

    2010-02-01

    Despite the widespread use of accreditation in many countries, and prevailing beliefs that accreditation is associated with variables contributing to clinical care and organisational outcomes, little systematic research has been conducted to examine its validity as a predictor of healthcare performance. To determine whether accreditation performance is associated with self-reported clinical performance and independent ratings of four aspects of organisational performance. Independent blinded assessment of these variables in a random, stratified sample of health service organisations. Acute care: large, medium and small health-service organisations in Australia. Study participants Nineteen health service organisations employing 16 448 staff treating 321 289 inpatients and 1 971 087 non-inpatient services annually, representing approximately 5% of the Australian acute care health system. Correlations of accreditation performance with organisational culture, organisational climate, consumer involvement, leadership and clinical performance. Results Accreditation performance was significantly positively correlated with organisational culture (rho=0.618, p=0.005) and leadership (rho=0.616, p=0.005). There was a trend between accreditation and clinical performance (rho=0.450, p=0.080). Accreditation was unrelated to organisational climate (rho=0.378, p=0.110) and consumer involvement (rho=0.215, p=0.377). Accreditation results predict leadership behaviours and cultural characteristics of healthcare organisations but not organisational climate or consumer participation, and a positive trend between accreditation and clinical performance is noted.

  12. Bioenergetic evaluation of diel vertical migration by bull trout (Salvelinus confluentus) in a thermally stratified reservoir

    Science.gov (United States)

    Eckmann, Madeleine; Dunham, Jason B.; Connor, Edward J.; Welch, Carmen A.

    2018-01-01

    Many species living in deeper lentic ecosystems exhibit daily movements that cycle through the water column, generally referred to as diel vertical migration (DVM). In this study, we applied bioenergetics modelling to evaluate growth as a hypothesis to explain DVM by bull trout (Salvelinus confluentus) in a thermally stratified reservoir (Ross Lake, WA, USA) during the peak of thermal stratification in July and August. Bioenergetics model parameters were derived from observed vertical distributions of temperature, prey and bull trout. Field sampling confirmed that bull trout prey almost exclusively on recently introduced redside shiner (Richardsonius balteatus). Model predictions revealed that deeper (>25 m) DVMs commonly exhibited by bull trout during peak thermal stratification cannot be explained by maximising growth. Survival, another common explanation for DVM, may have influenced bull trout depth use, but observations suggest there may be additional drivers of DVM. We propose these deeper summertime excursions may be partly explained by an alternative hypothesis: the importance of colder water for gametogenesis. In Ross Lake, reliance of bull trout on warm water prey (redside shiner) for consumption and growth poses a potential trade-off with the need for colder water for gametogenesis.

  13. Monoplane 3D-2D registration of cerebral angiograms based on multi-objective stratified optimization

    Science.gov (United States)

    Aksoy, T.; Špiclin, Ž.; Pernuš, F.; Unal, G.

    2017-12-01

    Registration of 3D pre-interventional to 2D intra-interventional medical images has an increasingly important role in surgical planning, navigation and treatment, because it enables the physician to co-locate depth information given by pre-interventional 3D images with the live information in intra-interventional 2D images such as x-ray. Most tasks during image-guided interventions are carried out under a monoplane x-ray, which is a highly ill-posed problem for state-of-the-art 3D to 2D registration methods. To address the problem of rigid 3D-2D monoplane registration we propose a novel multi-objective stratified parameter optimization, wherein a small set of high-magnitude intensity gradients are matched between the 3D and 2D images. The stratified parameter optimization matches rotation templates to depth templates, first sampled from projected 3D gradients and second from the 2D image gradients, so as to recover 3D rigid-body rotations and out-of-plane translation. The objective for matching was the gradient magnitude correlation coefficient, which is invariant to in-plane translation. The in-plane translations are then found by locating the maximum of the gradient phase correlation between the best matching pair of rotation and depth templates. On twenty pairs of 3D and 2D images of ten patients undergoing cerebral endovascular image-guided intervention the 3D to monoplane 2D registration experiments were setup with a rather high range of initial mean target registration error from 0 to 100 mm. The proposed method effectively reduced the registration error to below 2 mm, which was further refined by a fast iterative method and resulted in a high final registration accuracy (0.40 mm) and high success rate (> 96%). Taking into account a fast execution time below 10 s, the observed performance of the proposed method shows a high potential for application into clinical image-guidance systems.

  14. Hydrogeology and water quality of the Nanticoke Creek stratified-drift aquifer, near Endicott, New York

    Science.gov (United States)

    Kreitinger, Elizabeth A.; Kappel, William M.

    2014-01-01

    The Village of Endicott, New York, is seeking an alternate source of public drinking water with the potential to supplement their current supply, which requires treatment due to legacy contamination. The southerly-draining Nanticoke Creek valley, located north of the village, was identified as a potential water source and the local stratified-drift (valley fill) aquifer was investigated to determine its hydrogeologic and water-quality characteristics. Nanticoke Creek and its aquifer extend from the hamlet of Glen Aubrey, N.Y., to the village of Endicott, a distance of about 15 miles, where it joins the Susquehanna River and its aquifer. The glacial sediments that comprise the stratified-drift aquifer vary in thickness and are generally underlain by glacial till over Devonian-aged shale and siltstone. Groundwater is more plentiful in the northern part of the aquifer where sand and gravel deposits are generally more permeable than in the southern part of the aquifer where less-permeable unconsolidated deposits are found. Generally there is enough groundwater to supply most homeowner wells and in some cases, supply small public-water systems such as schools, mobile-home parks, and small commercial/industrial facilities. The aquifer is recharged by precipitation, runoff, and tributary streams. Most tributary streams flowing across alluvial deposits lose water to the aquifer as they flow off of their bedrock-lined channels and into the more permeable alluvial deposits at the edges of the valley. The quality of both surface water and groundwater is generally good. Some water wells do have water-quality issues related to natural constituents (manganese and iron) and several homeowners noted either the smell and (or) taste of hydrogen sulfide in their drinking water. Dissolved methane concentrations from five drinking-water wells were well below the potentially explosive value of 28 milligrams per liter. Samples from surface and groundwater met nearly all State and Federal

  15. New numerical approaches for modeling thermochemical convection in a compositionally stratified fluid

    Science.gov (United States)

    Puckett, Elbridge Gerry; Turcotte, Donald L.; He, Ying; Lokavarapu, Harsha; Robey, Jonathan M.; Kellogg, Louise H.

    2018-03-01

    Geochemical observations of mantle-derived rocks favor a nearly homogeneous upper mantle, the source of mid-ocean ridge basalts (MORB), and heterogeneous lower mantle regions. Plumes that generate ocean island basalts are thought to sample the lower mantle regions and exhibit more heterogeneity than MORB. These regions have been associated with lower mantle structures known as large low shear velocity provinces (LLSVPS) below Africa and the South Pacific. The isolation of these regions is attributed to compositional differences and density stratification that, consequently, have been the subject of computational and laboratory modeling designed to determine the parameter regime in which layering is stable and understanding how layering evolves. Mathematical models of persistent compositional interfaces in the Earth's mantle may be inherently unstable, at least in some regions of the parameter space relevant to the mantle. Computing approximations to solutions of such problems presents severe challenges, even to state-of-the-art numerical methods. Some numerical algorithms for modeling the interface between distinct compositions smear the interface at the boundary between compositions, such as methods that add numerical diffusion or 'artificial viscosity' in order to stabilize the algorithm. We present two new algorithms for maintaining high-resolution and sharp computational boundaries in computations of these types of problems: a discontinuous Galerkin method with a bound preserving limiter and a Volume-of-Fluid interface tracking algorithm. We compare these new methods with two approaches widely used for modeling the advection of two distinct thermally driven compositional fields in mantle convection computations: a high-order accurate finite element advection algorithm with entropy viscosity and a particle method that carries a scalar quantity representing the location of each compositional field. All four algorithms are implemented in the open source finite

  16. Feed-in tariffs versus quotas: how to promote renewable s and stimulate technical progress for cost decrease?

    International Nuclear Information System (INIS)

    Menanteau, Ph.; Finon, D.; Lamy, M.L.

    2002-01-01

    Incentive schemes for the development of renewable energy sources may focus on quantities (defining national targets and setting up bidding systems, or quota systems providing for green certificate trading), or they may focus on prices (feed-in tariffs). Whatever the system chosen, the role of the public authorities is quite specific: to stimulate technical progress and speed up the technological learning processes so that ultimately renewable energy technologies will be able to compete with conventional technologies, once the environmental costs have been internalized. A comparison of instruments must thus take into account the characteristics of the innovation process and adoption conditions (uncertainties regarding cost curves, learning effects) which means also looking at dynamic efficiency criteria. The paper concludes that a system of feed-in tariffs is more efficient than a bidding system, but highlights the theoretical interest of green certificate trading which must be confirmed through practice, given the influence of market structures and rules on the performance of this type of approach. (author)

  17. Experimental investigation of droplet separation in a horizontal counter-current air/water stratified flow

    International Nuclear Information System (INIS)

    Gabriel, Stephan Gerhard

    2015-01-01

    ). Measurements in the gaseous phase were carried out by conventional oil-droplets as tracer particles. The volumetric phase distribution was investigated by the new OVM method, which was developed within this work. The validation of this method was done by simultaneous measurements of the new method and an electrical conductivity probe in the WENKA channel. Finally, the droplet mass flux was measured by an isokinetic sampling probe, which was also developed within this work. The functional capability of the probe and the accuracy of isokinetic conditions were demonstrated by PIV-measurements under various flow conditions. The investigations include both supercritical and subcritical, stratified flows, with partially and fully reversed conditions. The behavior of both fluids was analyzed at four measurement sites and under 31 different volumetric flux conditions. The results include sequences of images and numerical data, providing an accurate impression of the flow behavior in the channel. This dataset can now be used for the development and validation of new turbulence and phase interaction models for stratified counter-current two-phase flows.

  18. Economic viability of Stratified Medicine concepts : An investor perspective on drivers and conditions that favour using Stratified Medicine approaches in a cost-contained healthcare environment

    NARCIS (Netherlands)

    Fugel, Hans-Joerg; Nuijten, Mark; Postma, Maarten

    2016-01-01

    RATIONALE: Stratified Medicine (SM) is becoming a natural result of advances in biomedical science and a promising path for the innovation-based biopharmaceutical industry to create new investment opportunities. While the use of biomarkers to improve R&D efficiency and productivity is very much

  19. Theoretical study of evaporation heat transfer in horizontal microfin tubes: stratified flow model

    Energy Technology Data Exchange (ETDEWEB)

    Honda, H; Wang, Y S [Kyushu Univ., Inst. for Materials Chemistry and Engineering, Kasuga, Fukuoka (Japan)

    2004-08-01

    The stratified flow model of evaporation heat transfer in helically grooved, horizontal microfin tubes has been developed. The profile of stratified liquid was determined by a theoretical model previously developed for condensation in horizontal microfin tubes. For the region above the stratified liquid, the meniscus profile in the groove between adjacent fins was determined by a force balance between the gravity and surface tension forces. The thin film evaporation model was applied to predict heat transfer in the thin film region of the meniscus. Heat transfer through the stratified liquid was estimated by using an empirical correlation proposed by Mori et al. The theoretical predictions of the circumferential average heat transfer coefficient were compared with available experimental data for four tubes and three refrigerants. A good agreement was obtained for the region of Fr{sub 0}<2.5 as long as partial dry out of tube surface did not occur. (Author)

  20. Mechanisms and Variability of Salt Transport in Partially-Stratified Estuaries

    National Research Council Canada - National Science Library

    Bowen, Melissa

    2000-01-01

    .... Analysis of salt transport from observations in the Hudson Estuary show that stratified periods with elevated estuarine salt transport occur in five-day intervals once a month during apogean neap tides...

  1. Visualization of mole fraction distribution of slow jet forming stably stratified field

    International Nuclear Information System (INIS)

    Fumizawa, Motoo; Hishida, Makoto

    1990-01-01

    An experimental study has been performed to investigate the behavior of flow and mass transfer in gaseous slow jet in which buoyancy force opposed the flow forming stably stratified field. The study has been performed to understand the basic features of air ingress phenomena at pipe rupture accident of the high temperature gas-cooled reactor. A displacement fringe technique was adopted in Mach-Zehnder interferometer to visualize the mole fraction distribution. As the result, the followings were obtained: (1) The stably stratified fields were formed in the vicinity of the outlet of the slow jet. The penetration distance of the stably stratified fields increased with Froude number. (2) Mass fraction distributions in the stably stratified fields were well correlated with the present model using the ramp mole velocity profile. (author)

  2. Stratifying a Risk for an Increased Variation of Airway Caliber among the Clinically Stable Asthma

    Directory of Open Access Journals (Sweden)

    Atsushi Hayata

    2013-01-01

    Conclusions: These results indicate that ACQ, %FEV1 and FENO can stratify the risk for increased variation in airway caliber among patients with stable asthma. This may help identify subjects in whom further monitoring of lung function fluctuations is indicated.

  3. Dipole formation by two interacting shielded monopoles in a stratified fluid

    NARCIS (Netherlands)

    Beckers, M.; Clercx, H.J.H.; Heijst, van G.J.F.; Verzicco, R.

    2002-01-01

    The interaction between two shielded monopolar vortices has been investigated experimentally in a nonrotating linearly stratified fluid and by full three-dimensional (3D) numerical simulations. The characteristic Reynolds and Froude numbers in the experiments are approximately Re [[approximate

  4. Molecular polymorphism of a cell surface proteoglycan: distinct structures on simple and stratified epithelia.

    Science.gov (United States)

    Sanderson, R D; Bernfield, M

    1988-12-01

    Epithelial cells are organized into either a single layer (simple epithelia) or multiple layers (stratified epithelia). Maintenance of these cellular organizations requires distinct adhesive mechanisms involving many cell surface molecules. One such molecule is a cell surface proteoglycan, named syndecan, that contains both heparan sulfate and chondroitin sulfate chains. This proteoglycan binds cells to fibrillar collagens and fibronectin and thus acts as a receptor for interstitial matrix. The proteoglycan is restricted to the basolateral surface of simple epithelial cells, but is located over the entire surface of stratified epithelial cells, even those surfaces not contacting matrix. We now show that the distinct localization in simple and stratified epithelia correlates with a distinct proteoglycan structure. The proteoglycan from simple epithelia (modal molecular size, 160 kDa) is larger than that from stratified epithelia (modal molecular size, 92 kDa), but their core proteins are identical in size and immunoreactivity. The proteoglycan from simple epithelia has more and larger heparan sulfate and chondroitin sulfate chains than the proteoglycan from stratified epithelia. Thus, the cell surface proteoglycan shows a tissue-specific structural polymorphism due to distinct posttranslational modifications. This polymorphism likely reflects distinct proteoglycan functions in simple and stratified epithelia, potentially meeting the different adhesive requirements of the cells in these different organizations.

  5. Geohydrology and water quality of stratified-drift aquifers in the lower Merrimack and coastal river basins, southeastern New Hampshire

    Science.gov (United States)

    Stekl, Peter J.; Flanagan, Sarah M.

    1992-01-01

    -water-level measurements and collect ground-water-quality samples. Surface-water-discharge measurements were made at 16 sites during low flow when the surface water is primarily ground-water discharge . These low-flow measurements indicate quantities of ground water potentially available from aquifers. Hydraulic conductivities of aquifer materials were estimated from grain-size-distribution data from 61 samples of stratified drift . Transmissivity was estimated from well logs by assigning hydraulic conductivity to specific well-log intervals, multiplying by the saturated thickness of the interval, and summing the results . Additional transmissivity values were obtained from an analysis of specific capacity and aquifer-test data. Long-term aquifer yields and contributing areas to hypothetical supply wells were estimated by application of a method that is analogous to super position and incorporates a ground-water-flow model developed by McDonald and Harbaugh (1988) . This method was applied to two aquifers judged to have the best potential for providing additional ground-water supplies. Samples of ground water from 26 test wells and 4 municipal wells were collected in March and August 1987 for analysis of common inorganic, organic, and volatile organic constituents. Methods for collecting and analyzing the samples are described by Fishman and Freidman (1989) . The water-quality results from the well samples were used to characterize background water quality in the stratified-drift aquifers.

  6. Nitrogen Isotopes and Chemocline Depth in Stratified Basins

    Science.gov (United States)

    Fulton, J. M.; Arthur, M. A.

    2006-12-01

    Black shale samples commonly have bulk δ15N values below 0‰, previously interpreted as the result of bacterial nitrogen fixation. In this study we examine the effect of chemocline depth on the δ15N values of water column particulate matter and sediments of two meromictic basins. In particular, we produced δ15N profiles of bulk Black Sea sediments, bulk sediments from Fayetteville Green Lake (FGL), and nutrients and particulates from FGL. We also analyzed pigments from FGL samples to trace the occurrences of deep-dwelling bacteria. Our results suggest that a shallow chemocline leads to relatively 15N-depleted sediments in the absence of nitrogen fixation, probably due to increased availability of ammonium for growth near the chemocline. FGL is meromictic with a shallow chemocline at 20 meters. Ammonium released in the monimolimnion and sediments supports productivity of cyanobacteria and purple (PSB) and green sulfur bacteria near and below the chemocline. The PSB at 20m generate 15N-depleted biomass (δ15N = -3‰), compared with 0 to 3‰ for deep water ammonium. High concentrations of Bchl a extracted from particulate matter at deeper depths, where high sulfide concentrations inhibit PSB growth, suggest that sinking particulate matter contains PSB biomass, transmitting the 15N-depleted signal to the sediments. The Black Sea chemocline depth has varied over the past 7500 years. Published biomarker and pyrite framboid size data suggest that a shallow chemocline persisted through much of the past 7500 years, except for three intervals when the chemocline was deeper than 205 meters. We have measured bulk δ15N on six cores spanning depths from 205 to 2088 meters. Each of the deep chemocline intervals coincides with basin-wide sedimentary δ15N values between 2 and 4‰, compared with values near or below 0‰ for periods characterized by a shallower chemocline. The most 15N-depleted values probably result from a much shallower chemocline than that at present

  7. Simulation model of stratified thermal energy storage tank using finite difference method

    Science.gov (United States)

    Waluyo, Joko

    2016-06-01

    Stratified TES tank is normally used in the cogeneration plant. The stratified TES tanks are simple, low cost, and equal or superior in thermal performance. The advantage of TES tank is that it enables shifting of energy usage from off-peak demand for on-peak demand requirement. To increase energy utilization in a stratified TES tank, it is required to build a simulation model which capable to simulate the charging phenomenon in the stratified TES tank precisely. This paper is aimed to develop a novel model in addressing the aforementioned problem. The model incorporated chiller into the charging of stratified TES tank system in a closed system. The model was developed in one-dimensional type involve with heat transfer aspect. The model covers the main factors affect to degradation of temperature distribution namely conduction through the tank wall, conduction between cool and warm water, mixing effect on the initial flow of the charging as well as heat loss to surrounding. The simulation model is developed based on finite difference method utilizing buffer concept theory and solved in explicit method. Validation of the simulation model is carried out using observed data obtained from operating stratified TES tank in cogeneration plant. The temperature distribution of the model capable of representing S-curve pattern as well as simulating decreased charging temperature after reaching full condition. The coefficient of determination values between the observed data and model obtained higher than 0.88. Meaning that the model has capability in simulating the charging phenomenon in the stratified TES tank. The model is not only capable of generating temperature distribution but also can be enhanced for representing transient condition during the charging of stratified TES tank. This successful model can be addressed for solving the limitation temperature occurs in charging of the stratified TES tank with the absorption chiller. Further, the stratified TES tank can be

  8. Relationships of the phase velocity with the microarchitectural parameters in bovine trabecular bone in vitro: Application of a stratified model

    Science.gov (United States)

    Lee, Kang Il

    2012-08-01

    The present study aims to provide insight into the relationships of the phase velocity with the microarchitectural parameters in bovine trabecular bone in vitro. The frequency-dependent phase velocity was measured in 22 bovine femoral trabecular bone samples by using a pair of transducers with a diameter of 25.4 mm and a center frequency of 0.5 MHz. The phase velocity exhibited positive correlation coefficients of 0.48 and 0.32 with the ratio of bone volume to total volume and the trabecular thickness, respectively, but a negative correlation coefficient of -0.62 with the trabecular separation. The best univariate predictor of the phase velocity was the trabecular separation, yielding an adjusted squared correlation coefficient of 0.36. The multivariate regression models yielded adjusted squared correlation coefficients of 0.21-0.36. The theoretical phase velocity predicted by using a stratified model for wave propagation in periodically stratified media consisting of alternating parallel solid-fluid layers showed reasonable agreements with the experimental measurements.

  9. Reliability of impingement sampling designs: An example from the Indian Point station

    International Nuclear Information System (INIS)

    Mattson, M.T.; Waxman, J.B.; Watson, D.A.

    1988-01-01

    A 4-year data base (1976-1979) of daily fish impingement counts at the Indian Point electric power station on the Hudson River was used to compare the precision and reliability of three random-sampling designs: (1) simple random, (2) seasonally stratified, and (3) empirically stratified. The precision of daily impingement estimates improved logarithmically for each design as more days in the year were sampled. Simple random sampling was the least, and empirically stratified sampling was the most precise design, and the difference in precision between the two stratified designs was small. Computer-simulated sampling was used to estimate the reliability of the two stratified-random-sampling designs. A seasonally stratified sampling design was selected as the most appropriate reduced-sampling program for Indian Point station because: (1) reasonably precise and reliable impingement estimates were obtained using this design for all species combined and for eight common Hudson River fish by sampling only 30% of the days in a year (110 d); and (2) seasonal strata may be more precise and reliable than empirical strata if future changes in annual impingement patterns occur. The seasonally stratified design applied to the 1976-1983 Indian Point impingement data showed that selection of sampling dates based on daily species-specific impingement variability gave results that were more precise, but not more consistently reliable, than sampling allocations based on the variability of all fish species combined. 14 refs., 1 fig., 6 tabs

  10. Hydrogeology and water quality of the stratified-drift aquifer in the Pony Hollow Creek Valley, Tompkins County, New York

    Science.gov (United States)

    Bugliosi, Edward F.; Miller, Todd S.; Reynolds, Richard J.

    2014-01-01

    The lithology, areal extent, and the water-table configuration in stratified-drift aquifers in the northern part of the Pony Hollow Creek valley in the Town of Newfield, New York, were mapped as part of an ongoing aquifer mapping program in Tompkins County. Surficial geologic and soil maps, well and test-boring records, light detection and ranging (lidar) data, water-level measurements, and passive-seismic surveys were used to map the aquifer geometry, construct geologic sections, and determine the depth to bedrock at selected locations throughout the valley. Additionally, water-quality samples were collected from selected streams and wells to characterize the quality of surface and groundwater in the study area. Sedimentary bedrock underlies the study area and is overlain by unstratified drift (till), stratified drift (glaciolacustrine and glaciofluvial deposits), and recent post glacial alluvium. The major type of unconsolidated, water-yielding material in the study area is stratified drift, which consists of glaciofluvial sand and gravel, and is present in sufficient amounts in most places to form an extensive unconfined aquifer throughout the study area, which is the source of water for most residents, farms, and businesses in the valleys. A map of the water table in the unconfined aquifer was constructed by using (1) measurements made between the mid-1960s through 2010, (2) control on the altitudes of perennial streams at 10-foot contour intervals from lidar data collected by Tompkins County, and (3) water surfaces of ponds and wetlands that are hydraulically connected to the unconfined aquifer. Water-table contours indicate that the direction of groundwater flow within the stratified-drift aquifer is predominantly from the valley walls toward the streams and ponds in the central part of the valley where groundwater then flows southwestward (down valley) toward the confluence with the Cayuta Creek valley. Locally, the direction of groundwater flow is radially

  11. Pedestrian-vehicle crashes and analytical techniques for stratified contingency tables.

    Science.gov (United States)

    Al-Ghamdi, Ali S

    2002-03-01

    In 1999 there were 450 fatalities due to road crashes in Riyadh, the capital of Saudi Arabia, of which 130 were pedestrians. Hence, every fourth person killed on the roads is a pedestrian. The aim of this study is to investigate pedestrian-vehicle crashes in this fast-growing city with two objectives in mind: to analyze pedestrian collisions with regard to their causes, characteristics, location of injury on the victim's body, and most common patterns and to determine the potential for use of the odds ratio technique in the analysis of stratified contingency tables. Data from 638 pedestrian-vehicle crashes reported by police, during the period 1997-1999, were used. A systematic sampling technique was followed in which every third record was used. The analysis showed that the pedestrian fatality rate per 10(5) population is 2.8. The rates were relatively high within the childhood (1-9 years) and young adult (10-19 years) groups, and the old-age groups (60 - > 80 years), which indicate that young as well as the elderly people in this city are more likely to be involved in fatal accidents of this type than are those in other age groups. The analysis revealed that 77.1% of pedestrians were probably struck while crossing a roadway either not in a crosswalk or where no crosswalk existed. In addition, the distribution of injuries on the victims' bodies was determined from hospital records. More than one-third of the fatal injuries were located on the head and chest. An attempt was made to conduct an association analysis between crash severity (i.e. injury or fatal) and some of the study variables using chi-square and odds ratio techniques. The categorical nature of the data helped in using these analytical techniques.

  12. A política de cotas na América Latina Evaluating the Results of Quota Systems in Politics in Latin America

    Directory of Open Access Journals (Sweden)

    MALA HTUN

    2001-01-01

    Full Text Available Tendo como pano de fundo o avanço na liderança das mulheres na América Latina, marcado pelo aumento do número de mulheres em cargos eletivos, pela adoção da política de cotas em muitos países e pelo crescimento do tema da igualdade entre mulheres e homens nos programas políticos, analisa-se a variação dos efeitos das políticas de cotas. Entre os fatores determinantes para os resultados destas políticas estão: a natureza do sistema eleitoral, com base em listas abertas ou listas fechadas; a existência ou não da norma de obrigatoriedade de posição competitiva das mulheres na lista partidária; e, finalmente, o compromisso partidário, no qual as políticas de cotas estão inseridas.This article discusses the varying effects of quota systems, as they emerge from a scenario of women's increased inroads into politics in Latin America, expressed in the increased number of women in elected offices, the implementation of quota systems and increased presence of the issue of gender equality in political agendas. The character of the electoral system, as based on "open" or "closed" lists; the absence or presence of a norm of a compulsory competitive position for women within political parties and political parties' commitment to quota policies are the crucial factors that determine variation.

  13. Spinning phenomena and energetics of spherically pulsating patterns in stratified fluids

    International Nuclear Information System (INIS)

    Ibragimov, Ranis N; Dameron, Michael

    2011-01-01

    The nonlinear solutions of the two-dimensional Boussinesq equations describing internal waves in rotating stratified fluids were obtained as group invariant solutions. The latter nonlinear solutions correspond to the rotation transformation preserving the form of the original nonlinear equations of motion. It is shown that the obtained class of exact solutions can be associated with the spherically pulsating patterns observed in uniformly stratified fluids. It is also shown that the obtained rotationally symmetric solutions are bounded functions that can be visualized as spinning patterns in stratified fluids. It is also shown that the rotational transformation provides the energy conservation law together with other conservation laws for which the spinning phenomena is observed. The effects of nonlinearity and the Earth's rotation on such a phenomenon are also discussed.

  14. Two-phase air-water stratified flow measurement using ultrasonic techniques

    International Nuclear Information System (INIS)

    Fan, Shiwei; Yan, Tinghu; Yeung, Hoi

    2014-01-01

    In this paper, a time resolved ultrasound system was developed for investigating two-phase air-water stratified flow. The hardware of the system includes a pulsed wave transducer, a pulser/receiver, and a digital oscilloscope. The time domain cross correlation method is used to calculate the velocity profile along ultrasonic beam. The system is able to provide velocities with spatial resolution of around 1mm and the temporal resolution of 200μs. Experiments were carried out on single phase water flow and two-phase air-water stratified flow. For single phase water flow, the flow rates from ultrasound system were compared with those from electromagnetic flow (EM) meter, which showed good agreement. Then, the experiments were conducted on two-phase air-water stratified flow and the results were given. Compared with liquid height measurement from conductance probe, it indicated that the measured velocities were explainable

  15. A criterion for the onset of slugging in horizontal stratified air-water countercurrent flow

    International Nuclear Information System (INIS)

    Chun, Moon-Hyun; Lee, Byung-Ryung; Kim, Yang-Seok

    1995-01-01

    This paper presents an experimental and theoretical investigation of wave height and transition criterion from wavy to slug flow in horizontal air-water countercurrent stratified flow conditions. A theoretical formula for the wave height in a stratified wavy flow regime has been developed using the concept of total energy balance over a wave crest to consider the shear stress acting on the interface of two fluids. From the limiting condition of the formula for the wave height, a necessary criterion for transition from a stratified wavy flow to a slug flow has been derived. A series of experiments have been conducted changing the non-dimensional water depth and the flow rates of air in a horizontal pipe and a duct. Comparisons between the measured data and the predictions of the present theory show that the agreement is within ±8%

  16. A criterion for the onset of slugging in horizontal stratified air-water countercurrent flow

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Moon-Hyun; Lee, Byung-Ryung; Kim, Yang-Seok [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)] [and others

    1995-09-01

    This paper presents an experimental and theoretical investigation of wave height and transition criterion from wavy to slug flow in horizontal air-water countercurrent stratified flow conditions. A theoretical formula for the wave height in a stratified wavy flow regime has been developed using the concept of total energy balance over a wave crest to consider the shear stress acting on the interface of two fluids. From the limiting condition of the formula for the wave height, a necessary criterion for transition from a stratified wavy flow to a slug flow has been derived. A series of experiments have been conducted changing the non-dimensional water depth and the flow rates of air in a horizontal pipe and a duct. Comparisons between the measured data and the predictions of the present theory show that the agreement is within {plus_minus}8%.

  17. Inhibition of Rho-associated kinases disturbs the collective cell migration of stratified TE-10 cells

    Directory of Open Access Journals (Sweden)

    Taro Mikami

    2015-01-01

    Full Text Available BACKGROUND: The collective cell migration of stratified epithelial cells is considered to be an important phenomenon in wound healing, development, and cancer invasion; however, little is known about the mechanisms involved. Furthermore, whereas Rho family proteins, including RhoA, play important roles in cell migration, the exact role of Rho-associated coiled coil-containing protein kinases (ROCKs in cell migration is controversial and might be cell-type dependent. Here, we report the development of a novel modified scratch assay that was used to observe the collective cell migration of stratified TE-10 cells derived from a human esophageal cancer specimen. RESULTS: Desmosomes were found between the TE-10 cells and microvilli of the surface of the cell sheet. The leading edge of cells in the cell sheet formed a simple layer and moved forward regularly; these rows were followed by the stratified epithelium. ROCK inhibitors and ROCK small interfering RNAs (siRNAs disturbed not only the collective migration of the leading edge of this cell sheet, but also the stratified layer in the rear. In contrast, RhoA siRNA treatment resulted in more rapid migration of the leading rows and disturbed movement of the stratified portion. CONCLUSIONS: The data presented in this study suggest that ROCKs play an important role in mediating the collective migration of TE-10 cell sheets. In addition, differences between the effects of siRNAs targeting either RhoA or ROCKs suggested that distinct mechanisms regulate the collective cell migration in the simple epithelium of the wound edge versus the stratified layer of the epithelium.

  18. Numerical simulation of stratified flows with different k-ε turbulence models

    International Nuclear Information System (INIS)

    Dagestad, S.

    1991-01-01

    The thesis comprises the numerical simulation of stratified flows with different k-ε models. When using the k-ε model, two equations are solved to describe the turbulence. The k-equation represents the turbulent kinetic energy of the turbulence and the ε-equation is the turbulent dissipation. Different k-ε models predict stratified flows differently. The standard k-ε model leads to higher turbulent mixing than the low-Reynolds model does. For lower Froude numbers, F 0 , this effect becomes enhanced. Buoyancy extension of the k-ε model also leads to less vertical mixing in cases with strong stratification. When the stratification increases, buoyancy-extension becomes larger influence. The turbulent Prandtl number effects have large impact on the transport of heat and the development of the flow. Two different formulae which express the turbulent Prandtl effects have been tested. For unstably stratified flows, the rapid mixing and three-dimensionality of the flow can in fact be computed using a k-ε model when buoyancy-extended is employed. The turbulent heat transfer and thus turbulent production in unstable stratified flows depends strongly upon the turbulent Prandtl number effect. The main conclusions are: Stable stratified flows should be computed with a buoyancy-extended low-Reynolds k-ε model; Unstable stratified flows should be computed with a buoyancy-extended standard k-ε model; The turbulent Prandtl number effects should be included in the computations; Buoyancy-extension has lead to more correct description of the physics for all of the investigated flows. 78 refs., 128 figs., 17 tabs

  19. Experimental observation of the stratified electrothermal instability on aluminum with thickness greater than a skin depth

    Science.gov (United States)

    Hutchinson, T. M.; Awe, T. J.; Bauer, B. S.; Yates, K. C.; Yu, E. P.; Yelton, W. G.; Fuelling, S.

    2018-05-01

    A direct observation of the stratified electrothermal instability on the surface of thick metal is reported. Aluminum rods coated with 70 μ m Parylene-N were driven to 1 MA in 100 ns , with the metal thicker than the skin depth. The dielectric coating suppressed plasma formation, enabling persistent observation of discrete azimuthally correlated stratified thermal perturbations perpendicular to the current whose wave numbers, k , grew exponentially with rate γ (k ) =0.06 n s-1-(0.4 n s-1μ m2ra d-2 ) k2 in ˜1 g /c m3 , ˜7000 K aluminum.

  20. Stereo imaging and random array stratified imaging for cargo radiation inspecting

    International Nuclear Information System (INIS)

    Wang Jingjin; Zeng Yu

    2003-01-01

    This paper presents a Stereo Imaging and Random Array Stratified Imaging for cargo container radiation Inspecting. By using dual-line vertical detector array scan, a stereo image of inspected cargo can be obtained and watched with virtual reality view. The random detector array has only one-row of detectors but distributed in a certain horizontal dimension randomly. To scan a cargo container with this random array detector, a 'defocused' image is obtained. By using 'anti-random focusing', one layer of the image can be focused on the background of all defocused images from other layers. A stratified X-ray image of overlapped bike wheels is presented

  1. Experimental Observation of the Stratified Electrothermal Instability on Aluminum with Thickness Greater than a Skin Depth

    Energy Technology Data Exchange (ETDEWEB)

    Hutchinson, Trevor M. [Univ. of Nevada, Reno, NV (United States); Hutchinson, Trevor M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Awe, Thomas James [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bauer, Bruno S. [Univ. of Nevada, Reno, NV (United States); Yates, Kevin [Univ. of New Mexico, Albuquerque, NM (United States); Yu, Edmund p. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Yelton, William G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Fuelling, Stephan [Univ. of Nevada, Reno, NV (United States)

    2017-07-01

    The first direct observation of the stratified electrothermal instability on the surface of thick metal is reported. Aluminum rods coated with 70 μm Parylene-N were driven to 1 MA in approximately 100 ns, with the metal thicker than the skin depth. The dielectric coating suppressed plasma formation, enabling persistent observation of discrete azimuthally-correlated stratified structures perpendicular to the current. Strata amplitudes grow rapidly, while their Fourier spectrum shifts toward longer wavelength. Assuming blackbody emission, radiometric calculations indicate strata are temperature perturbations that grow exponentially with rate γ = 0.04 ns -1 in 3000- 10,000 K aluminum.

  2. An analysis direct-contact condensation in horizontal cocurrent stratified flow of steam and cold water

    International Nuclear Information System (INIS)

    Lee, Suk Ho; Kim, Hho Jung

    1992-01-01

    The physical benchmark problem on the direct-contact condensation under the horizontal cocurrent stratified flow was analyzed using the RELAP5/MOD2 and /MOD3 one-dimensional model. Analysis was performed for the Northwestern experiments, which involved condensing steam/water flow in a rectangular channel. The study showed that the RELAP5 interfacial heat transfer model, under the horizontal stratified flow regime, predicted the condensation rate well though the interfacial heat transfer area was underpredicted. However, some discrepancies in water layer thickness and local heat transfer coefficient with experimental results were found especially when there is a wavy interface, and those were satisfied only within the range. (Author)

  3. Knowledge, attitudes, and perceptions of autism spectrum disorder in a stratified sampling of preschool teachers in China.

    Science.gov (United States)

    Liu, Yingna; Li, Jialing; Zheng, Qiaolan; Zaroff, Charles M; Hall, Brian J; Li, Xiuhong; Hao, Yuantao

    2016-05-13

    In China, children with Autism Spectrum Disorder (ASD) can potentially benefit from universal education policies and recent initiatives designed to address the needs of children with developmental disorders. However, adequate schooling is often unavailable for children with ASD, in part because teachers lack the knowledge and skills needed to work with this population. To better understand the current state of knowledge of ASD in China, we surveyed knowledge and attitudes regarding the disorder in preschool teachers. A total of 471 preschool teachers in the cities of Guangzhou and Foshan, China completed questionnaires assessing participant demographics, knowledge of typical child development and knowledge of ASD, attitudes towards ASD, practices and self-perceptions of efficacy in the education of children with ASD, and awareness of organizations and intervention approaches devoted to the care of individuals with ASD. The correlation between individual- and school-level variables with current knowledge of typical child development and ASD was examined using univariate and multivariate analyses. The majority (84%) of participants answered correctly more than half of the questionnaire items assessing understanding of typical child development. In contrast, 83% provided inaccurate responses to more than half of the questionnaire items assessing knowledge of ASD. Knowledge of typical child development and knowledge of ASD were both associated with geographic region (teachers in Guangzhou had greater knowledge than those in Foshan, p teachers in China, and greater teacher training and instruction is needed. Nonetheless, teachers report a willingness and motivation to gain the skills needed to maximize the educational experiences of children with ASD.

  4. Sample size estimation and sampling techniques for selecting a representative sample

    Directory of Open Access Journals (Sweden)

    Aamir Omair

    2014-01-01

    Full Text Available Introduction: The purpose of this article is to provide a general understanding of the concepts of sampling as applied to health-related research. Sample Size Estimation: It is important to select a representative sample in quantitative research in order to be able to generalize the results to the target population. The sample should be of the required sample size and must be selected using an appropriate probability sampling technique. There are many hidden biases which can adversely affect the outcome of the study. Important factors to consider for estimating the sample size include the size of the study population, confidence level, expected proportion of the outcome variable (for categorical variables/standard deviation of the outcome variable (for numerical variables, and the required precision (margin of accuracy from the study. The more the precision required, the greater is the required sample size. Sampling Techniques: The probability sampling techniques applied for health related research include simple random sampling, systematic random sampling, stratified random sampling, cluster sampling, and multistage sampling. These are more recommended than the nonprobability sampling techniques, because the results of the study can be generalized to the target population.

  5. Gender Stratified Monopoly: Why Do I Earn Less and Pay More?

    Science.gov (United States)

    Smith, Stacy L.

    2017-01-01

    A modified version of Monopoly has long been used as a simulation exercise to teach inequality. Versions of Modified Monopoly (MM) have touched on minority status relative to inequality but without an exploration of the complex interaction between minority status and class. This article introduces Gender Stratified Monopoly (GSM), an adaptation…

  6. Modeling the Conducting Stably-Stratified Layer of the Earth's Core

    Science.gov (United States)

    Petitdemange, L.; Philidet, J.; Gissinger, C.

    2017-12-01

    Observations of the Earth magnetic field as well as recent theoretical works tend to show that the Earth's outer liquid core is mostly comprised of a convective zone in which the Earth's magnetic field is generated - likely by dynamo action -, but also features a thin, stably stratified layer at the top of the core.We carry out direct numerical simulations by modeling this thin layer as an axisymmetric spherical Couette flow for a stably stratified fluid embedded in a dipolar magnetic field. The dynamo region is modeled by a conducting inner core rotating slightly faster than the insulating mantle due to magnetic torques acting on it, such that a weak differential rotation (low Rossby limit) can develop in the stably stratified layer.In the case of a non-stratified fluid, the combined action of the differential rotation and the magnetic field leads to the well known regime of `super-rotation', in which the fluid rotates faster than the inner core. Whereas in the classical case, this super-rotation is known to vanish in the magnetostrophic limit, we show here that the fluid stratification significantly extends the magnitude of the super-rotation, keeping this phenomenon relevant for the Earth core. Finally, we study how the shear layers generated by this new state might give birth to magnetohydrodynamic instabilities or waves impacting the secular variations or jerks of the Earth's magnetic field.

  7. Modification of Measures of Acute Kidney Injury to Risk Stratify Combat Casualties

    Science.gov (United States)

    2017-08-26

    REPORT TYPE 08/26/2017 Poster 4. TJTLE AND SUBTITLE t\\.1odification of l’vfeasures,of Acute Kidney Injury to Risk Stratify Cotnbat Casualties 6...profiles and potential future conflicts , identifying acute kidney injury (AKI) early can help us determine the need for rapidity of evacuation

  8. Dominance of a clonal green sulfur bacterial population in a stratified lake

    DEFF Research Database (Denmark)

    Gregersen, Lea H; Habicht, Kirsten S; Peduzzi, Sandro

    2009-01-01

    surveys using FISH cell counting and population multilocus sequence typing [clone library sequence analysis of the small subunit (SSU) rRNA locus and two loci involved in photosynthesis in GSB: fmoA and csmCA]. All bacterial populations clearly stratified according to water column chemistry. The GSB...

  9. Measures to assess the prognostic ability of the stratified Cox proportional hazards model

    DEFF Research Database (Denmark)

    (Tybjaerg-Hansen, A.) The Fibrinogen Studies Collaboration.The Copenhagen City Heart Study; Tybjærg-Hansen, Anne

    2009-01-01

    Many measures have been proposed to summarize the prognostic ability of the Cox proportional hazards (CPH) survival model, although none is universally accepted for general use. By contrast, little work has been done to summarize the prognostic ability of the stratified CPH model; such measures...

  10. Analysing stratified medicine business models and value systems: innovation-regulation interactions.

    Science.gov (United States)

    Mittra, James; Tait, Joyce

    2012-09-15

    Stratified medicine offers both opportunities and challenges to the conventional business models that drive pharmaceutical R&D. Given the increasingly unsustainable blockbuster model of drug development, due in part to maturing product pipelines, alongside increasing demands from regulators, healthcare providers and patients for higher standards of safety, efficacy and cost-effectiveness of new therapies, stratified medicine promises a range of benefits to pharmaceutical and diagnostic firms as well as healthcare providers and patients. However, the transition from 'blockbusters' to what might now be termed 'niche-busters' will require the adoption of new, innovative business models, the identification of different and perhaps novel types of value along the R&D pathway, and a smarter approach to regulation to facilitate innovation in this area. In this paper we apply the Innogen Centre's interdisciplinary ALSIS methodology, which we have developed for the analysis of life science innovation systems in contexts where the value creation process is lengthy, expensive and highly uncertain, to this emerging field of stratified medicine. In doing so, we consider the complex collaboration, timing, coordination and regulatory interactions that shape business models, value chains and value systems relevant to stratified medicine. More specifically, we explore in some depth two convergence models for co-development of a therapy and diagnostic before market authorisation, highlighting the regulatory requirements and policy initiatives within the broader value system environment that have a key role in determining the probable success and sustainability of these models. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Experimental investigation on isothermal stratified flow mixing in a horizontal T-junction

    Energy Technology Data Exchange (ETDEWEB)

    Isaev, Alexander; Kulenovic, Rudi; Laurien, Eckart [Stuttgart Univ. (Germany). Inst. fuer Kernenergetik und Energiesysteme (IKE)

    2016-10-15

    Turbulent and stratified flows can lead to thermal fatigue in piping systems of nuclear power plants (NPP). Such flows can be investigated in the University of Stuttgart Fluid-Structure-Interaction (FSI) facility with a T-Junction at thermal conditions with temperature differences of up to 255 K and at pressures of maximum 75 bars.

  12. Mathematical modeling of turbulent stratified flows. Application of liquid metal fast breeders

    Energy Technology Data Exchange (ETDEWEB)

    Villand, M; Grand, D [CEA-Service des Transferts Thermiques, Grenoble (France)

    1983-07-01

    Mathematical model of turbulent stratified flow was proposed under the following assumptions: Newtonian fluid; incompressible fluid; coupling between temperature and momentum fields according to Boussinesq approximation; two-dimensional invariance for translation or rotation; coordinates cartesian or curvilinear. Solutions obtained by the proposed method are presented.

  13. The Fokker-Planck equation for ray dispersion in gyrotropic stratified media

    NARCIS (Netherlands)

    Golynski, S.M.

    1984-01-01

    The Hamilton equations of geometrical optics determine the rays of the relevant wave field in the short wavelength. We give a systematic derivation of the Fokker-Planck equation for the joint probability density of the position and unit direction vector of rays propagating in a gyrotropic stratified

  14. Design and simulation of stratified probability digital receiver with application to the multipath communication

    Science.gov (United States)

    Deal, J. H.

    1975-01-01

    One approach to the problem of simplifying complex nonlinear filtering algorithms is through using stratified probability approximations where the continuous probability density functions of certain random variables are represented by discrete mass approximations. This technique is developed in this paper and used to simplify the filtering algorithms developed for the optimum receiver for signals corrupted by both additive and multiplicative noise.

  15. Computational Fluid Dynamics model of stratified atmospheric boundary-layer flow

    DEFF Research Database (Denmark)

    Koblitz, Tilman; Bechmann, Andreas; Sogachev, Andrey

    2015-01-01

    For wind resource assessment, the wind industry is increasingly relying on computational fluid dynamics models of the neutrally stratified surface-layer. So far, physical processes that are important to the whole atmospheric boundary-layer, such as the Coriolis effect, buoyancy forces and heat...

  16. Internal wave patterns in enclosed density-stratified and rotating fluids

    NARCIS (Netherlands)

    Manders, A.M.A.

    2003-01-01

    Stratified fluids support internal waves, which propagate obliquely through the fluid. The angle with respectto the stratification direction is contrained: it is purely determined by the wave frequency and the strength of the density stratification (internal gravity waves) or the rotation rate

  17. Seasonal cyclogenesis and the role of near-surface stratified layer in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Murty, V.S.N.; Sarma, M.S.S.; Tilvi, V.

    The role of the near-surface stratified layer developed due to the spread of low salinity waters under the influence of freshwater influx on the cyclogenesis over the Bay of Bengal is addressed. The seasonal variation of the Effective Oceanic Layer...

  18. A review of recent developments on turbulent entrainment in stratified flows

    International Nuclear Information System (INIS)

    Cotel, Aline J

    2010-01-01

    Stratified interfaces are present in many geophysical flow situations, and transport across such an interface is an essential factor for correctly evaluating the physical processes taking place at many spatial and temporal scales in such flows. In order to accurately evaluate vertical and lateral transport occurring when a turbulent flow impinges on a stratified interface, the turbulent entrainment and vorticity generation mechanisms near the interface must be understood and quantified. Laboratory experiments were performed for three flow configurations: a vertical thermal, a sloping gravity current and a vertical turbulent jet with various tilt angles and precession speeds. All three flows impinged on an interface separating a two-layer stably stratified environment. The entrainment rate is quantified for each flow using laser-induced fluorescence and compared to predictions of Cotel and Breidenthal (1997 Appl. Sci. Res. 57 349-66). The possible applications of transport across stratified interfaces include the contribution of hydrothermal plumes to the global ocean energy budget, turbidity currents on the ocean floor, the design of lake de-stratification systems, modeling gas leaks from storage reservoirs, weather forecasting and global climate change.

  19. A random spatial sampling method in a rural developing nation

    Science.gov (United States)

    Michelle C. Kondo; Kent D.W. Bream; Frances K. Barg; Charles C. Branas

    2014-01-01

    Nonrandom sampling of populations in developing nations has limitations and can inaccurately estimate health phenomena, especially among hard-to-reach populations such as rural residents. However, random sampling of rural populations in developing nations can be challenged by incomplete enumeration of the base population. We describe a stratified random sampling method...

  20. Economic viability of Stratified Medicine concepts: An investor perspective on drivers and conditions that favour using Stratified Medicine approaches in a cost-contained healthcare environment.

    Science.gov (United States)

    Fugel, Hans-Joerg; Nuijten, Mark; Postma, Maarten

    2016-12-25

    Stratified Medicine (SM) is becoming a natural result of advances in biomedical science and a promising path for the innovation-based biopharmaceutical industry to create new investment opportunities. While the use of biomarkers to improve R&D efficiency and productivity is very much acknowledged by industry, much work remains to be done to understand the drivers and conditions that favour using a stratified approach to create economically viable products and to justify the investment in SM interventions as a stratification option. In this paper we apply a decision analytical methodology to address the economic attractiveness of different SM development options in a cost-contained healthcare environment. For this purpose, a hypothetical business case in the oncology market has been developed considering four feasible development scenarios. The article outlines the effects of development time and time to peak sales as key economic value drivers influencing profitability of SM interventions under specific conditions. If regulatory and reimbursement challenges can be solved, decreasing development time and enhancing early market penetration would most directly improve the economic attractiveness of SM interventions. Appropriate tailoring of highly differentiated patient subgroups is the prerequisite to leverage potential efficiency gains in the R&D process. Also, offering a better targeted and hence ultimately more cost-effective therapy at reimbursable prices will facilitate time to market access and allow increasing market share gains within the targeted populations. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. General Practitioners' and patients' perceptions towards stratified care: a theory informed investigation.

    Science.gov (United States)

    Saunders, Benjamin; Bartlam, Bernadette; Foster, Nadine E; Hill, Jonathan C; Cooper, Vince; Protheroe, Joanne

    2016-08-31

    Stratified primary care involves changing General Practitioners' (GPs) clinical behaviour in treating patients, away from the current stepped care approach to instead identifying early treatment options that are matched to patients' risk of persistent disabling pain. This article explores the perspectives of UK-based GPs and patients about a prognostic stratified care model being developed for patients with the five most common primary care musculoskeletal pain presentations. The focus was on views about acceptability, and anticipated barriers and facilitators to the use of stratified care in routine practice. Four focus groups and six semi-structured telephone interviews were conducted with GPs (n = 23), and three focus groups with patients (n = 20). Data were analysed thematically; and identified themes examined in relation to the Theoretical Domains Framework (TDF), which facilitates comprehensive identification of behaviour change determinants. A critical approach was taken in using the TDF, examining the nuanced interrelationships between theoretical domains. Four key themes were identified: Acceptability of clinical decision-making guided by stratified care; impact on the therapeutic relationship; embedding a prognostic approach within a biomedical model; and practical issues in using stratified care. Whilst within each theme specific findings are reported, common across themes was the identified relationships between the theoretical domains of knowledge, skills, professional role and identity, environmental context and resources, and goals. Through analysis of these identified relationships it was found that, for GPs and patients to perceive stratified care as being acceptable, it must be seen to enhance GPs' knowledge and skills, not undermine GPs' and patients' respective identities and be integrated within the environmental context of the consultation with minimal disruption. Findings highlight the importance of taking into account the context of

  2. Evaluation of electrophoretic profile and albumin quota in the cerebrospinal fluid of dogs with distemper showing or not neurvous signs Avaliação do perfil eletroforético e da cota de albumina do líquido cerebrospinal de cães acometidos pela cinomose apresentando ou não sinais neurológicos

    Directory of Open Access Journals (Sweden)

    F.G.V. Gama

    2007-02-01

    Full Text Available The electrophoretic profile of cerebrospinal fluid proteins and albumin quota was studied in healthy dogs and dogs with distemper in either nervous or non-nervous phases. Cerebrospinal fluid (CSF samples from 30 dogs were collected by puncture of the cisterna magna. The total protein content, the albumin quota, and the electrophoretic fraction of CSF proteins in agarose gel plates were evaluated. Results were similar in healthy dogs and dogs with distemper and no nervous signs, but were significantly increased in the group of dogs with distemper showing nervous signs. The study of CSF protein profile proved useful and contributed significantly on the detection of central nervous system disorders and damages to the blood-brain barrier during the nervous phase of distemper.Estudaram-se o perfil eletroforético das proteínas liquóricas e a cota de albumina em cães sem e com cinomose na fase neurológica e não-neurológica. A punção da cisterna magna para a obtenção de amostras de liquor realizou-se em 30 cães. Analisaram-se teores de proteínas totais, cota de albumina e fracionamento eletroforético das proteínas liquóricas em gel de agarose. Os resultados foram semelhantes nos cães normais e nos cães com cinomose sem sinais neurológicos e significativamente elevados no grupo de cães com cinomose apresentando sinais neurológicos. O estudo do quadro protéico do líquido cérebroespinhal foi útil e contribuiu significativamente na detecção de lesões ao sistema nervoso central e de danos à barreira hematoencefálica durante a fase neurológica da cinomose.

  3. Boat sampling

    International Nuclear Information System (INIS)

    Citanovic, M.; Bezlaj, H.

    1994-01-01

    This presentation describes essential boat sampling activities: on site boat sampling process optimization and qualification; boat sampling of base material (beltline region); boat sampling of weld material (weld No. 4); problems accompanied with weld crown varieties, RPV shell inner radius tolerance, local corrosion pitting and water clarity. The equipment used for boat sampling is described too. 7 pictures

  4. Graph sampling

    OpenAIRE

    Zhang, L.-C.; Patone, M.

    2017-01-01

    We synthesise the existing theory of graph sampling. We propose a formal definition of sampling in finite graphs, and provide a classification of potential graph parameters. We develop a general approach of Horvitz–Thompson estimation to T-stage snowball sampling, and present various reformulations of some common network sampling methods in the literature in terms of the outlined graph sampling theory.

  5. Seasonal variability of Dinophysis spp. and Protoceratium reticulatum associated to lipophilic shellfish toxins in a strongly stratified Chilean fjord

    Science.gov (United States)

    Alves-de-Souza, Catharina; Varela, Daniel; Contreras, Cristóbal; de La Iglesia, Pablo; Fernández, Pamela; Hipp, Byron; Hernández, Cristina; Riobó, Pilar; Reguera, Beatriz; Franco, José M.; Diogène, Jorge; García, Carlos; Lagos, Néstor

    2014-03-01

    The fine scale vertical distribution of Dinophysis spp. and Protoceratium reticulatum (potential producers of lipophilic shellfish toxins, LSTs) and its relation with LSTs in shellfish was studied in Reloncaví fjord, a strongly stratified system in Southern Chile. Samples were taken over two years from late spring to early autumn (2007-2008 period) and from early spring to late summer (2008-2009 period). Dinophysis spp., in particular Dinophysis acuminata, were always detected, often forming thin layers in the region of the salinity driven pycnocline, with cell maxima for D. acuminata of 28.5×103 cells L-1 in March 2008 and 17.1×103 cells L-1 in November 2008. During the 2008-2009 sampling period, blooms of D. acuminata co-occurred with high densities of cryptophyceans and the ciliate Mesodinium spp. The highest levels of pectenotoxin-2 (PTX-2; 2.2 ng L-1) were found in the plankton in February 2009, associated with moderate densities of D. acuminata, Dinophysis tripos and Dinophysis subcircularis (0.1-0.6×103 cells L-1). However, only trace levels of PTX-2 were observed in bivalves at that time. Dinophysistoxin (DTX-1 and DTX-3) levels in bivalves and densities of Dinophysis spp. were not well correlated. Low DTX levels in bivalves observed during a major bloom of D. acuminata in March 2008 suggested that there is a large seasonal intraspecific variability in toxin content of Dinophysis spp. driven by changes in population structure associated with distinct LST toxin profiles in Reloncaví fjord during the study period. A heterogeneous vertical distribution was also observed for P. reticulatum, whose presence was restricted to summer months. A bloom of this species of 2.2×103 cells L-1 at 14 m depth in February 2009 was positively correlated with high concentrations of yessotoxins in bivalves (51-496 ng g-1) and plankton samples (3.2 ng L-1). Our results suggest that a review of monitoring strategies for Dinophysis spp. in strongly stratified fjord systems

  6. Mixed Convection Flow along a Stretching Cylinder in a Thermally Stratified Medium

    Directory of Open Access Journals (Sweden)

    Swati Mukhopadhyay

    2012-01-01

    Full Text Available An analysis for the axisymmetric laminar boundary layer mixed convection flow of a viscous and incompressible fluid towards a stretching cylinder immersed in a thermally stratified medium is presented in this paper. Similarity transformation is employed to convert the governing partial differential equations into highly nonlinear ordinary differential equations. Numerical solutions of these equations are obtained by a shooting method. It is found that the heat transfer rate at the surface is lower for flow in a thermally stratified medium compared to that of an unstratified medium. Moreover, both the skin friction coefficient and the heat transfer rate at the surface are larger for a cylinder compared to that for a flat plate.

  7. Doubly stratified mixed convection flow of Maxwell nanofluid with heat generation/absorption

    Energy Technology Data Exchange (ETDEWEB)

    Abbasi, F.M., E-mail: abbasisarkar@gmail.com [Department of Mathematics, Comsats Institute of Information Technology, Islamabad 44000 (Pakistan); Shehzad, S.A. [Department of Mathematics, Comsats Institute of Information Technology, Sahiwal 57000 (Pakistan); Hayat, T. [Department of Mathematics, Quaid-i-Azam University, 45320, Islamabad 44000 (Pakistan); NAAM Research Group, Department of Mathematics, Faculty of Science, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Ahmad, B. [NAAM Research Group, Department of Mathematics, Faculty of Science, King Abdulaziz University, Jeddah 21589 (Saudi Arabia)

    2016-04-15

    Magnetohydrodynamic (MHD) doubly stratified flow of Maxwell nanofluid in presence of mixed convection is analyzed in this article. Effects of thermophoresis, Brownian motion and heat generation/absorption are present. The flow is induced due to linear stretching of sheet. Mathematical formulation is made under boundary layer approach. Expressions of velocity, temperature and nanoparticles concentration are developed. The obtained results are plotted and discussed to examine the variations in temperature and nanoparticles concentration due to different physical parameters. Numerical computations are made to obtain the values of local Nusselt and Sherwood numbers. Impact of sundry parameters on the flow quantities is analyzed graphically. - Highlights: • Double stratified flow of Maxwell nanofluid with mixed convection is modeled. • Thermophoresis and Brownian motion effects are encountered. • Computations are made to obtain the solution expressions. • Numerical values of local Nusselt and Sherwood numbers are computed and examined.

  8. Experimental and numerical investigation of stratified gas-liquid flow in inclined circular pipes

    International Nuclear Information System (INIS)

    Faccini, J.L.H.; Sampaio, P.A.B. de; Botelho, M.H.D.S.; Cunha, M.V.; Cunha Filho, J.S.; Su, J.

    2012-01-01

    In this paper, a stratified gas-liquid flow is experimentally and numerically investigated. Two measurement techniques, namely an ultrasonic technique and a visualization technique, are applied on an inclined circular test section using a fast single transducer pulse-echo technique and a high-speed camera. A numerical model is employed to simulate the stratified gas-liquid flow, formed by a system of non-linear differential equations consisting of the Reynolds averaged Navier-Stokes equations with the κ-ω turbulence model. The test section used in this work is comprised mainly of a transparent circular pipe with inner diameter 1 inch, and inclination angles varying from -2.5 to -10.0 degrees. Numerical solutions are obtained for the liquid height as a function of inclination angles, and compared with our own experimental data. (author)

  9. Analysis of natural convection heat transfer and flows in internally heated stratified liquid pools

    International Nuclear Information System (INIS)

    Gubaidullin, A.A. Jr.; Dinh, T.N.; Sehgal, B.R.

    1999-01-01

    In this paper, natural convection flows and heat transfer in a liquid pool, with two superposed immiscible fluid layers, are analyzed. The objective of the study is to examine the effect of interfacial hydrodynamics and to develop a method which enables energy splitting to be evaluated in a stratified liquid pool. The thermal convection, with and without an internal heat source, in a rectangular cavity with different pairs of fluids was numerically simulated by a CFD code FLOW-3D. It was found that the code performs very well for prediction of heat transfer coefficients for different conditions. The hydrodynamic coupling between immiscible layers was found to have minor, if any, impact on the natural convection heat transfer for the conditions examined. Calculated results were used to develop, and validate, a new correlation for energy splitting and for heat transfer in stratified liquid pools

  10. Numerical simulation of stratified shear flow using a higher order Taylor series expansion method

    Energy Technology Data Exchange (ETDEWEB)

    Iwashige, Kengo; Ikeda, Takashi [Hitachi, Ltd. (Japan)

    1995-09-01

    A higher order Taylor series expansion method is applied to two-dimensional numerical simulation of stratified shear flow. In the present study, central difference scheme-like method is adopted for an even expansion order, and upwind difference scheme-like method is adopted for an odd order, and the expansion order is variable. To evaluate the effects of expansion order upon the numerical results, a stratified shear flow test in a rectangular channel (Reynolds number = 1.7x10{sup 4}) is carried out, and the numerical velocity and temperature fields are compared with experimental results measured by laser Doppler velocimetry thermocouples. The results confirm that the higher and odd order methods can simulate mean velocity distributions, root-mean-square velocity fluctuations, Reynolds stress, temperature distributions, and root-mean-square temperature fluctuations.

  11. Stratified polymer brushes from microcontact printing of polydopamine initiator on polymer brush surfaces.

    Science.gov (United States)

    Wei, Qiangbing; Yu, Bo; Wang, Xiaolong; Zhou, Feng

    2014-06-01

    Stratified polymer brushes are fabricated using microcontact printing (μCP) of initiator integrated polydopamine (PDOPBr) on polymer brush surfaces and the following surface initiated atom transfer radical polymerization (SI-ATRP). It is found that the surface energy, chemically active groups, and the antifouling ability of the polymer brushes affect transfer efficiency and adhesive stability of the polydopamine film. The stickiness of the PDOPBr pattern on polymer brush surfaces is stable enough to perform continuous μCP and SI-ATRP to prepare stratified polymer brushes with a 3D topography, which have broad applications in cell and protein patterning, biosensors, and hybrid surfaces. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Turbulent transport of passive scalar behind line sources in an unstably stratified open channel flow

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chun-Ho [The Hong Kong Polytechnic University, Kowloon (Hong Kong). Department of Building and Real Estate; Leung, Dennis Y.C. [The University of Hong Kong (Hong Kong). Department of Mechanical Engineering

    2006-11-15

    This study employs a direct numerical simulation (DNS) technique to study the flow, turbulence structure, and passive scalar plume transport behind line sources in an unstably stratified open channel flow. The scalar transport behaviors for five emission heights (z{sub s}=0, 0.25H, 0.5H, 0.75H, and H, where H is the channel height) at a Reynolds number of 3000, a Prandtl number and a Schmidt number of 0.72, and a Richardson number of -0.2 are investigated. The vertically meandering mean plume heights and dispersion coefficients calculated by the current DNS model agree well with laboratory results and field measurements in literature. It is found that the plume meandering is due to the movement of the positive and negative vertical turbulent scalar fluxes above and below the mean plume heights, respectively. These findings help explaining the plume meandering mechanism in the unstably stratified atmospheric boundary layer. (author)

  13. Quantum image pseudocolor coding based on the density-stratified method

    Science.gov (United States)

    Jiang, Nan; Wu, Wenya; Wang, Luo; Zhao, Na

    2015-05-01

    Pseudocolor processing is a branch of image enhancement. It dyes grayscale images to color images to make the images more beautiful or to highlight some parts on the images. This paper proposes a quantum image pseudocolor coding scheme based on the density-stratified method which defines a colormap and changes the density value from gray to color parallel according to the colormap. Firstly, two data structures: quantum image GQIR and quantum colormap QCR are reviewed or proposed. Then, the quantum density-stratified algorithm is presented. Based on them, the quantum realization in the form of circuits is given. The main advantages of the quantum version for pseudocolor processing over the classical approach are that it needs less memory and can speed up the computation. Two kinds of examples help us to describe the scheme further. Finally, the future work are analyzed.

  14. The New Rich and Their Unplanned Births: Stratified Reproduction under China's Birth-planning Policy.

    Science.gov (United States)

    Shi, Lihong

    2017-12-01

    This article explores the creation and ramifications of a stratified reproductive system under China's state control of reproduction. Within this system, an emerging group of "new rich" are able to circumvent birth regulations and have unplanned births because of their financial capabilities and social networks. While China's birth-planning policy is meant to be enforced equally for all couples, the unequal access to wealth and bureaucratic power as a result of China's widening social polarization has created disparate reproductive rights and experiences. This article identifies three ways in which reproductive privileges are created. It further explores how a stratified reproductive system under state population control reinforces social polarization. While many socially marginalized couples are unable to register their unplanned children for citizenship status and social benefits, the new rich are able to legitimate their births and transfer their privilege and status to their children, thus reproducing a new generation of elites. © 2016 by the American Anthropological Association.

  15. The effect of sediments on turbulent plume dynamics in a stratified fluid

    Science.gov (United States)

    Stenberg, Erik; Ezhova, Ekaterina; Brandt, Luca

    2017-11-01

    We report large eddy simulation results of sediment-loaded turbulent plumes in a stratified fluid. The configuration, where the plume is discharged from a round source, provides an idealized model of subglacial discharge from a submarine tidewater glacier and is a starting point for understanding the effect of sediments on the dynamics of the rising plume. The transport of sediments is modeled by means of an advection-diffusion equation where sediment settling velocity is taken into account. We initially follow the experimental setup of Sutherland (Phys. Rev. Fluids, 2016), considering uniformly stratified ambients and further extend the work to pycnocline-type stratifications typical of Greenland fjords. Apart from examining the rise height, radial spread and intrusion of the rising plume, we gain further insights of the plume dynamics by extracting turbulent characteristics and the distribution of the sediments inside the plume.

  16. Emerging Techniques in Stratified Designs and Continuous Gradients for Tissue Engineering of Interfaces

    Science.gov (United States)

    Dormer, Nathan H.; Berkland, Cory J.; Detamore, Michael S.

    2013-01-01

    Interfacial tissue engineering is an emerging branch of regenerative medicine, where engineers are faced with developing methods for the repair of one or many functional tissue systems simultaneously. Early and recent solutions for complex tissue formation have utilized stratified designs, where scaffold formulations are segregated into two or more layers, with discrete changes in physical or chemical properties, mimicking a corresponding number of interfacing tissue types. This method has brought forth promising results, along with a myriad of regenerative techniques. The latest designs, however, are employing “continuous gradients” in properties, where there is no discrete segregation between scaffold layers. This review compares the methods and applications of recent stratified approaches to emerging continuously graded methods. PMID:20411333

  17. Scattering by multiple parallel radially stratified infinite cylinders buried in a lossy half space.

    Science.gov (United States)

    Lee, Siu-Chun

    2013-07-01

    The theoretical solution for scattering by an arbitrary configuration of closely spaced parallel infinite cylinders buried in a lossy half space is presented in this paper. The refractive index and permeability of the half space and cylinders are complex in general. Each cylinder is radially stratified with a distinct complex refractive index and permeability. The incident radiation is an arbitrarily polarized plane wave propagating in the plane normal to the axes of the cylinders. Analytic solutions are derived for the electric and magnetic fields and the Poynting vector of backscattered radiation emerging from the half space. Numerical examples are presented to illustrate the application of the scattering solution to calculate backscattering from a lossy half space containing multiple homogeneous and radially stratified cylinders at various depths and different angles of incidence.

  18. 3D elastic inversion of vertical seismic profiles in horizontally stratified media; Inversion elastique 3D de profils sismiques verticaux en milieux stratifies horizontalement

    Energy Technology Data Exchange (ETDEWEB)

    Petit, J.L.

    1997-07-21

    This thesis is devoted to the inversion of VSP (vertical seismic profile) seismic data in order to determine the elastic properties of horizontally stratified media. The VSP records are computed using the full wave elastic modelling in isotropic and transversely isotropic media using Hankel transform, a finite difference scheme and an inverse Hankel transform algorithm, and the propagation equations are determined and numerically solved; the importance of considering a 3D wave propagation model instead of a 1 D one is emphasized. The theoretical VSP inverse problem is then considered, with the seismic waveform inversion set as a least-squares problem, consisting in recovering the distribution of physical parameters which minimize the misfit between calculated and observed VSP. The corresponding problem requires the knowledge of the source function

  19. Sensitivity of the Geomagnetic Octupole to a Stably Stratified Layer in the Earth's Core

    Science.gov (United States)

    Yan, C.; Stanley, S.

    2017-12-01

    The presence of a stably stratified layer at the top of the core has long been proposed for Earth, based on evidence from seismology and geomagnetic secular variation. Geodynamo modeling offers a unique window to inspect the properties and dynamics in Earth's core. For example, numerical simulations have shown that magnetic field morphology is sensitive to the presence of stably stratified layers in a planet's core. Here we use the mMoSST numerical dynamo model to investigate the effects of a thin stably stratified layer at the top of the fluid outer core in Earth on the resulting large-scale geomagnetic field morphology. We find that the existence of a stable layer has significant influence on the octupolar component of the magnetic field in our models, whereas the quadrupole doesn't show an obvious trend. This suggests that observations of the geomagnetic field can be applied to provide information of the properties of this plausible stable layer, such as how thick and how stable this layer could be. Furthermore, we have examined whether the dominant thermal signature from mantle tomography at the core-mantle boundary (CMB) (a degree & order 2 spherical harmonic) can influence our results. We found that this heat flux pattern at the CMB has no outstanding effects on the quadrupole and octupole magnetic field components. Our studies suggest that if there is a stably stratified layer at the top of the Earth's core, it must be limited in terms of stability and thickness, in order to be compatible with the observed paleomagnetic record.

  20. A Case Study on Stratified Settlement and Rebound Characteristics due to Dewatering in Shanghai Subway Station

    OpenAIRE

    Wang, Jianxiu; Huang, Tianrong; Sui, Dongchang

    2013-01-01

    Based on the Yishan Metro Station Project of Shanghai Metro Line number 9, a centrifugal model test was conducted to investigate the behavior of stratified settlement and rebound (SSR) of Shanghai soft clay caused by dewatering in deep subway station pit. The soil model was composed of three layers, and the dewatering process was simulated by self-invention of decompressing devise. The results indicate that SSR occurs when the decompression was carried out, and only negative rebound was found...

  1. Advanced liquid-cooled, turbocharged and intercooled stratified charge rotary engines for aircraft

    Science.gov (United States)

    Mount, Robert E.; Bartel, John; Hady, William F.

    1987-01-01

    Developments concerning stratified-charge rotary (SCR) engines over the past 10 years are reviewed. Aircraft engines being developed using SCR technology are shown and described, and the ability of such technology to meet general aviation engine needs is considered. Production timing and availability of SCR technology for the development of aviation rotary engines are discussed, and continuing efforts toward improving this technology, including NASA efforts, are described.

  2. Generation of stratified squamous epithelial progenitor cells from mouse induced pluripotent stem cells.

    Directory of Open Access Journals (Sweden)

    Satoru Yoshida

    Full Text Available BACKGROUND: Application of induced pluripotent stem (iPS cells in regenerative medicine will bypass ethical issues associated with use of embryonic stem cells. In addition, patient-specific IPS cells can be useful to elucidate the pathophysiology of genetic disorders, drug screening, and tailor-made medicine. However, in order to apply iPS cells to mitotic tissue, induction of tissue stem cells that give rise to progeny of the target organ is required. METHODOLOGY/PRINCIPAL FINDINGS: We induced stratified epithelial cells from mouse iPS cells by co-culture with PA6 feeder cells (SDIA-method with use of BMP4. Clusters of cells positive for the differentiation markers KRT1 or KRT12 were observed in KRT14-positive colonies. We successfully cloned KRT14 and p63 double-positive stratified epithelial progenitor cells from iPS-derived epithelial cells, which formed stratified epithelial sheets consisting of five- to six-polarized epithelial cells in vitro. When these clonal cells were cultured on denuded mouse corneas, a robust stratified epithelial layer was observed with physiological cell polarity including high levels of E-cadherin, p63 and K15 expression in the basal layer and ZO-1 in the superficial layer, recapitulating the apico-basal polarity of the epithelium in vivo. CONCLUSIONS/SIGNIFICANCE: These results suggest that KRT14 and p63 double-positive epithelial progenitor cells can be cloned from iPS cells in order to produce polarized multilayer epithelial cell sheets.

  3. Spatial Analysis of Geothermal Resource Potential in New York and Pennsylvania: A Stratified Kriging Approach

    Science.gov (United States)

    Smith, J. D.; Whealton, C. A.; Stedinger, J. R.

    2014-12-01

    Resource assessments for low-grade geothermal applications employ available well temperature measurements to determine if the resource potential is sufficient for supporting district heating opportunities. This study used a compilation of bottomhole temperature (BHT) data from recent unconventional shale oil and gas wells, along with legacy oil, gas, and storage wells, in Pennsylvania (PA) and New York (NY). Our study's goal was to predict the geothermal resource potential and associated uncertainty for the NY-PA region using kriging interpolation. The dataset was scanned for outliers, and some observations were removed. Because these wells were drilled for reasons other than geothermal resource assessment, their spatial density varied widely. An exploratory spatial statistical analysis revealed differences in the spatial structure of the geothermal gradient data (the kriging semi-variogram and its nugget variance, shape, sill, and the degree of anisotropy). As a result, a stratified kriging procedure was adopted to better capture the statistical structure of the data, to generate an interpolated surface, and to quantify the uncertainty of the computed surface. The area was stratified reflecting different physiographic provinces in NY and PA that have geologic properties likely related to variations in the value of the geothermal gradient. The kriging prediction and the variance-of-prediction were determined for each province by the generation of a semi-variogram using only the wells that were located within that province. A leave-one-out cross validation (LOOCV) was conducted as a diagnostic tool. The results of stratified kriging were compared to kriging using the whole region to determine the impact of stratification. The two approaches provided similar predictions of the geothermal gradient. However, the variance-of-prediction was different. The stratified approach is recommended because it gave a more appropriate site-specific characterization of uncertainty

  4. Experiments on the Microenvironment and Breathing of a Person in Isothermal and Stratified Surroundings

    DEFF Research Database (Denmark)

    Nielsen, Peter V.; Jensen, Rasmus Lund; Litewnicki, Michal

    2009-01-01

    This study investigates the characteristics of human exhalation. Experiments are performed on a breathing thermal manikin in a test room. The manikin is heated, and an artificial lung is used to generate varying air flows with specific flow rates and temperatures for breathing. Smoke visualisation...... is used to show the formation, movement and disappearance of the exhalation jets from both nose and mouth. The exhalation of breathing without ventilation in the room, and with stratified surroundings (displacement ventilation) is analysed....

  5. Stratified prevention: opportunities and limitations. Report on the 1st interdisciplinary cardiovascular workshop in Augsburg.

    Science.gov (United States)

    Kirchhof, Gregor; Lindner, Josef Franz; Achenbach, Stephan; Berger, Klaus; Blankenberg, Stefan; Fangerau, Heiner; Gimpel, Henner; Gassner, Ulrich M; Kersten, Jens; Magnus, Dorothea; Rebscher, Herbert; Schunkert, Heribert; Rixen, Stephan; Kirchhof, Paulus

    2018-03-01

    Sufficient exercise and sleep, a balanced diet, moderate alcohol consumption and a good approach to handle stress have been known as lifestyles that protect health and longevity since the Middle Age. This traditional prevention quintet, turned into a sextet by smoking cessation, has been the basis of the "preventive personality" that formed in the twentieth century. Recent analyses of big data sets including genomic and physiological measurements have unleashed novel opportunities to estimate individual health risks with unprecedented accuracy, allowing to target preventive interventions to persons at high risk and at the same time to spare those in whom preventive measures may not be needed or even be harmful. To fully grasp these opportunities for modern preventive medicine, the established healthy life styles require supplementation by stratified prevention. The opportunities of these developments for life and health contrast with justified concerns: A "surveillance society", able to predict individual behaviour based on big data, threatens individual freedom and jeopardises equality. Social insurance law and the new German Disease Prevention Act (Präventionsgesetz) rightly stress the need for research to underpin stratified prevention which is accessible to all, ethical, effective, and evidence based. An ethical and acceptable development of stratified prevention needs to start with autonomous individuals who control and understand all information pertaining to their health. This creates a mandate for lifelong health education, enabled in an individualised form by digital technology. Stratified prevention furthermore requires the evidence-based development of a new taxonomy of cardiovascular diseases that reflects disease mechanisms. Such interdisciplinary research needs broad support from society and a better use of biosamples and data sets within an updated research governance framework.

  6. Sampling in Developmental Science: Situations, Shortcomings, Solutions, and Standards.

    Science.gov (United States)

    Bornstein, Marc H; Jager, Justin; Putnick, Diane L

    2013-12-01

    Sampling is a key feature of every study in developmental science. Although sampling has far-reaching implications, too little attention is paid to sampling. Here, we describe, discuss, and evaluate four prominent sampling strategies in developmental science: population-based probability sampling, convenience sampling, quota sampling, and homogeneous sampling. We then judge these sampling strategies by five criteria: whether they yield representative and generalizable estimates of a study's target population, whether they yield representative and generalizable estimates of subsamples within a study's target population, the recruitment efforts and costs they entail, whether they yield sufficient power to detect subsample differences, and whether they introduce "noise" related to variation in subsamples and whether that "noise" can be accounted for statistically. We use sample composition of gender, ethnicity, and socioeconomic status to illustrate and assess the four sampling strategies. Finally, we tally the use of the four sampling strategies in five prominent developmental science journals and make recommendations about best practices for sample selection and reporting.

  7. Sampling in Developmental Science: Situations, Shortcomings, Solutions, and Standards

    Science.gov (United States)

    Bornstein, Marc H.; Jager, Justin; Putnick, Diane L.

    2014-01-01

    Sampling is a key feature of every study in developmental science. Although sampling has far-reaching implications, too little attention is paid to sampling. Here, we describe, discuss, and evaluate four prominent sampling strategies in developmental science: population-based probability sampling, convenience sampling, quota sampling, and homogeneous sampling. We then judge these sampling strategies by five criteria: whether they yield representative and generalizable estimates of a study’s target population, whether they yield representative and generalizable estimates of subsamples within a study’s target population, the recruitment efforts and costs they entail, whether they yield sufficient power to detect subsample differences, and whether they introduce “noise” related to variation in subsamples and whether that “noise” can be accounted for statistically. We use sample composition of gender, ethnicity, and socioeconomic status to illustrate and assess the four sampling strategies. Finally, we tally the use of the four sampling strategies in five prominent developmental science journals and make recommendations about best practices for sample selection and reporting. PMID:25580049

  8. Effect of stratified inequality of blood flow on gas exchange in liquid-filled lungs.

    Science.gov (United States)

    West, J. B.; Maloney, J. E.; Castle, B. L.

    1972-01-01

    This investigation set out to answer two questions: (1) are the distal alveoli in the terminal lung units less well perfused than the proximal alveoli, i.e., is there stratification of blood flow; and (2) if so, does this enhance gas exchange in the presence of stratified inequality of ventilation. Excised dog lungs were ventilated with saline and perfused with blood. Following single inspirations of xenon 133 in saline and various periods of breath holding, the expired xenon concentration against volume was measured and it confirmed marked stratified inequality of ventilation under these conditions. By measuring the rate of depletion of xenon from alveoli during a period of blood flow, we showed that the alveoli which emptied at the end of expiration had 16% less blood flow than those exhaling earlier. However, by measuring the xenon concentration in pulmonary venous blood, we found that about 10% less tracer was transferred from the alveoli into the blood when the inspired xenon was stratified within the respiratory zone. Thus while stratification of blood flow was confirmed, it was shown to impair rather than enhance the efficiency of gas transfer.

  9. Energy Cascade from Internal Modes in Non-uniformly Stratified Fluid through Excitation of Superharmonic Disturbances

    Science.gov (United States)

    Sutherland, B. R.

    2016-02-01

    It is well established that two-dimensional internal plane waves and modes in uniformly stratified fluid efficiently transfer energy to smaller scale waves and ultimately turbulent mixing through parametric subharmonic instability (PSI). The numerical simulations of MacKinnon & Winters (GRL 2005) predicted PSI should act efficiently to disrupt the internal tide. However, while in situ observations showed the presence of PSI, it was not found to be appreciable. One reason for the discrepancy between simulations and observations is that the former examined an internal mode in uniformly stratified fluid whereas, in reality, the internal tide exists in non-uniform stratification and is manifest as sinusoidal oscillations of the thermocline. Through theory supported by numerical simulations, it is shown that internal modes in non-uniform stratification immediately excite superharmonics, not subharmonic disturbances. These have double the horizontal wavenumber and double the frequency of the parent mode and hence move with the same horizontal phase speed of the parent mode. As the disturbances grow in amplitude, however, they interact with the parent mode generating small-scale vertically propagating internal waves within the strongly stratified layer. The occurrence of PSI over very long times can occur, as in the simulations of Hazewinkel and Winters (JPO 2011). However, a comprehensive understanding of the energy cascade from the internal tide to small scales must consider the evolution of excited superharmonic disturbances.

  10. Theory of hyperbolic stratified nanostructures for surface-enhanced Raman scattering

    Science.gov (United States)

    Wong, Herman M. K.; Dezfouli, Mohsen Kamandar; Axelrod, Simon; Hughes, Stephen; Helmy, Amr S.

    2017-11-01

    We theoretically investigate the enhancement of surface enhanced Raman spectroscopy (SERS) using hyperbolic stratified nanostructures and compare to metal nanoresonators. The photon Green function of each nanostructure within its environment is first obtained from a semianalytical modal theory, which is used in a quantum optics formalism of the molecule-nanostructure interaction to model the SERS spectrum. An intuitive methodology is presented for calculating the single-molecule enhancement factor (SMEF), which is also able to predict known experimental SERS enhancement factors of a gold nanodimer. We elucidate the important figures-of-merit of the enhancement and explore these for different designs. We find that the use of hyperbolic stratified materials can enhance the photonic local density of states (LDOS) by close to two times in comparison to pure metal nanostructures, when both designed to work at the same operating wavelengths. However, the increased LDOS is accompanied by higher electric field concentration within the lossy hyperbolic material, which leads to increased quenching that serves to reduce the overall detected SERS enhancement in the far field. For nanoresonators with resonant localized surface plasmon wavelengths in the near-infrared, the SMEF for the hyperbolic stratified nanostructure is approximately one order of magnitude lower than the pure metal counterpart. Conversely, we show that by detecting the Raman signal using a near-field probe, hyperbolic materials can provide an improvement in SERS enhancement compared to using pure metal nanostructures when the probe is sufficiently close (<50 nm ) to the Raman active molecule at the plasmonic hotspot.

  11. Interfacial transport characteristics in a gas-liquid or an immiscible liquid-liquid stratified flow

    International Nuclear Information System (INIS)

    Inoue, A.; Aoki, S.; Aritomi, M.; Kozawa, Y.

    1982-01-01

    This paper is a review for an interfacial transport characteristics of mass, momentum and energy in a gas-liquid or a immiscible liquid-liquid stratified flow with wavy interface which have been studied in our division. In the experiment, a characteristic of wave motion and its effect to the turbulence near the interface as well as overall flow characteristics like pressure drop, position of the interface were investigated in an air-water, an air-mercury and a water-liquid metal stratified flow. On the other hand, several models based on the mixing length model and a two-equation model of turbulence, with special interfacial boundary conditions in which the wavy surface was regarded as a rough surface correspond to the wavy height, a source of turbulent energy equal to the wave energy and a damped-turbulence due to the surface tension, were proposed to predict the flow characteristics and the interfacial heat transfer in a fully developed and an undeveloped stratified flow and examined by the experimental data. (author)

  12. Experimental analysis of an oblique turbulent flame front propagating in a stratified flow

    Energy Technology Data Exchange (ETDEWEB)

    Galizzi, C.; Escudie, D. [Universite de Lyon, CNRS, CETHIL, INSA-Lyon, UMR5008, F-69621 Cedex (France)

    2010-12-15

    This paper details the experimental study of a turbulent V-shaped flame expanding in a nonhomogeneous premixed flow. Its aim is to characterize the effects of stratification on turbulent flame characteristics. The setup consists of a stationary V-shaped flame stabilized on a rod and expanding freely in a lean premixed methane-air flow. One of the two oblique fronts interacts with a stratified slice, which has an equivalence ratio close to one and a thickness greater than that of the flame front. Several techniques such as PIV and CH{sup *} chemiluminescence are used to investigate the instantaneous fields, while laser Doppler anemometry and thermocouples are combined with a concentration probe to provide information on the mean fields. First, in order to provide a reference, the homogeneous turbulent case is studied. Next, the stratified turbulent premixed flame is investigated. Results show significant modifications of the whole flame and of the velocity field upstream of the flame front. The analysis of the geometric properties of the stratified flame indicates an increase in flame brush thickness, closely related to the local equivalence ratio. (author)

  13. RANS Modeling of Stably Stratified Turbulent Boundary Layer Flows in OpenFOAM®

    Directory of Open Access Journals (Sweden)

    Wilson Jordan M.

    2015-01-01

    Full Text Available Quantifying mixing processes relating to the transport of heat, momentum, and scalar quantities of stably stratified turbulent geophysical flows remains a substantial task. In a stably stratified flow, such as the stable atmospheric boundary layer (SABL, buoyancy forces have a significant impact on the flow characteristics. This study investigates constant and stability-dependent turbulent Prandtl number (Prt formulations linking the turbulent viscosity (νt and diffusivity (κt for modeling applications of boundary layer flows. Numerical simulations of plane Couette flow and pressure-driven channel flow are performed using the Reynolds-averaged Navier-Stokes (RANS framework with the standard k-ε turbulence model. Results are compared with DNS data to evaluate model efficacy for predicting mean velocity and density fields. In channel flow simulations, a Prandtl number formulation for wall-bounded flows is introduced to alleviate overmixing of the mean density field. This research reveals that appropriate specification of Prt can improve predictions of stably stratified turbulent boundary layer flows.

  14. Stratified flows and internal waves in the Vema Fracture Zone of the Mid Atlantic Ridge

    Science.gov (United States)

    Makarenko, Nikolay; Morozov, Eugene; Tarakanov, Roman; Demidova, Tatiana; Frey, Dmitri; Grigorenko, Klim

    2017-04-01

    In this paper, we study stratified flows and internal waves in the Vema fracture zone of the Mid Atlantic Ridge. This fracture provides intense transportation of cold abyssal waters from the West Atlantic to the equatorial region of the East Atlantic [1]. The results of measurements [2,3] carried out in the cruises of RV Akademik Sergey Vavilov in 2014-2016 are presented. The structure of the near-bottom flow is studied experimentally on the basis of CTD- and LADCP profiling. Theoretical analysis involves mathematical formulation of stratified fluid flow which uses CTD-data obtained from field observation. Spectral properties and kinematic characteristics of internal waves are calculated and discussed. This work was supported by RFBR (grants No 15-01-03942, 16-35-50158). References [1] Morozov E., Demidov A., Tarakanov R. and Zenk W. Abyssal Channels in the Atlantic Ocean: Water Structure and Flows, Springer, Dordrecht, 2010. [2] Morozov E.G., Tarakanov R.Yu., and Makarenko N.I. Flows of Antarctic Bottom Water through fractures in the southern part of the North Mid Atlantic Ridge, Oceanology, 2015, 55, 796-800. [3] Grigorenko K.S., Makarenko N.I., Morozov E.G., Tarakanov R.Yu., and Frey D.I. Stratified flows and internal waves in the Central West Atlantic, J. Physics: Conf. Series, 2016, 722, 012011.

  15. Turbulent circulation above the surface heat source in stably stratified atmosphere

    Science.gov (United States)

    Kurbatskii, A. F.; Kurbatskaya, L. I.

    2016-10-01

    The 3-level RANS approach for simulating a turbulent circulation over the heat island in a stably stratified environment under nearly calm conditions is formulated. The turbulent kinetic energy its spectral consumption (dissipation) and the dispersion of turbulent fluctuations of temperature are found from differential equations, thus the correct modeling of transport processes in the interface layer with the counter-gradient heat flux is assured. The three-parameter turbulence RANS approach minimizes difficulties in simulating the turbulent transport in a stably stratified environment and reduces efforts needed for the numerical implementation of the 3-level RANS approach. Numerical simulation of the turbulent structure of the penetrative convection over the heat island under conditions of stably stratified atmosphere demonstrates that the three-equation model is able to predict the thermal circulation induced by the heat island. The temperature distribution, root-mean-square fluctuations of the turbulent velocity and temperature fields and spectral turbulent kinetic energy flux are in good agreement with the experimental data. The model describes such thin physical effects, as a crossing of vertical profiles of temperature of a thermal plume with the formation of the negative buoyancy area testifying to development of the dome-shaped form at the top part of a plume in the form of "hat".

  16. VENDOR SELECTION AND DETERMINING PROCUREMENT QUOTAS IN CONDITIONS WHEN DISCOUNTS ARE OFFERED ON THE TOTAL VALUE OF THE CONTRACTED PROCUREMENT OF MANY DIFFERENT PRODUCTS

    Directory of Open Access Journals (Sweden)

    Zoran Babic

    2012-04-01

    Full Text Available Vendor selection is a very significant business problem for ensuring the competitiveness on the market. That is why companies pay great attention to this problem. To solve the vendor selection problems can be applied to a number of quantitative methods. Depending on the goals of the company the vendor selection can be a mono-criterion or multi-criterion programming problem. This paper deals with the problem of vendor selection and determining procurement quotas from selected vendors under conditions where vendors offer discounts to the total order value within a specified period where the buyer buys more products from the vendors. The total value of procurement costs in a given period is taken as an optimization criterion. In this paper the specific flour purchase problem is solved for a company that manufactures bakery products

  17. VENDOR SELECTION AND DETERMINING PROCUREMENT QUOTAS IN CONDITIONS WHEN DISCOUNTS ARE OFFERED ON THE TOTAL VALUE OF THE CONTRACTED PROCUREMENT OF MANY DIFFERENT PRODUCTS

    Directory of Open Access Journals (Sweden)

    Zoran Babić

    2012-04-01

    Full Text Available Vendor selection is a very significant business problem for ensuring the competitiveness on the market. That is why companies pay great attention to this problem. To solve the vendor selection problems can be applied to a number of quantitative methods. Depending on the goals of the company the vendor selection can be a mono-criterion or multi-criterion programming problem. This paper deals with the problem of vendor selection and determining procurement quotas from selected vendors under conditions where vendors offer discounts to the total order value within a specified period where the buyer buys more products from the vendors. The total value of procurement costs in a given period is taken as an optimization criterion. In this paper the specific flour purchase problem is solved for a company that manufactures bakery products.

  18. Implementing the Keele stratified care model for patients with low back pain: an observational impact study.

    Science.gov (United States)

    Bamford, Adrian; Nation, Andy; Durrell, Susie; Andronis, Lazaros; Rule, Ellen; McLeod, Hugh

    2017-02-03

    The Keele stratified care model for management of low back pain comprises use of the prognostic STarT Back Screening Tool to allocate patients into one of three risk-defined categories leading to associated risk-specific treatment pathways, such that high-risk patients receive enhanced treatment and more sessions than medium- and low-risk patients. The Keele model is associated with economic benefits and is being widely implemented. The objective was to assess the use of the stratified model following its introduction in an acute hospital physiotherapy department setting in Gloucestershire, England. Physiotherapists recorded data on 201 patients treated using the Keele model in two audits in 2013 and 2014. To assess whether implementation of the stratified model was associated with the anticipated range of treatment sessions, regression analysis of the audit data was used to determine whether high- or medium-risk patients received significantly more treatment sessions than low-risk patients. The analysis controlled for patient characteristics, year, physiotherapists' seniority and physiotherapist. To assess the physiotherapists' views on the usefulness of the stratified model, audit data on this were analysed using framework methods. To assess the potential economic consequences of introducing the stratified care model in Gloucestershire, published economic evaluation findings on back-related National Health Service (NHS) costs, quality-adjusted life years (QALYs) and societal productivity losses were applied to audit data on the proportion of patients by risk classification and estimates of local incidence. When the Keele model was implemented, patients received significantly more treatment sessions as the risk-rating increased, in line with the anticipated impact of targeted treatment pathways. Physiotherapists were largely positive about using the model. The potential annual impact of rolling out the model across Gloucestershire is a gain in approximately 30

  19. Direct numerical simulation of thermally-stratified turbulent boundary layer subjected to adverse pressure gradient

    International Nuclear Information System (INIS)

    Hattori, Hirofumi; Kono, Amane; Houra, Tomoya

    2016-01-01

    Highlights: • We study various thermally-stratified turbulent boundary layers having adverse pressure gradient (APG) by means of DNS. • The detailed turbulent statistics and structures in various thermally-stratified turbulent boundary layers having APG are discussed. • It is found that the friction coefficient and Stanton number decrease along the streamwise direction due to the effects of stable thermal stratification and APG, but those again increase due to the APG effect in the case of weak stable thermal stratification. • In the case of strong stable stratification with or without APG, the flow separation is observed in the downstream region. - Abstract: The objective of this study is to investigate and observe turbulent heat transfer structures and statistics in thermally-stratified turbulent boundary layers subjected to a non-equilibrium adverse pressure gradient (APG) by means of direct numerical simulation (DNS). DNSs are carried out under conditions of neutral, stable and unstable thermal stratifications with a non-equilibrium APG, in which DNS results reveal heat transfer characteristics of thermally-stratified non-equilibrium APG turbulent boundary layers. In cases of thermally-stratified turbulent boundary layers affected by APG, heat transfer performances increase in comparison with a turbulent boundary layer with neutral thermal stratification and zero pressure gradient (ZPG). Especially, it is found that the friction coefficient and Stanton number decrease along the streamwise direction due to the effects of stable thermal stratification and APG, but those again increase due to the APG effect in the case of weak stable thermal stratification (WSBL). Thus, the analysis for both the friction coefficient and Stanton number in the case of WSBL with/without APG is conducted using the FIK identity in order to investigate contributions from the transport equations, in which it is found that both Reynolds-shear-stress and the mean convection terms

  20. Coordinación de canales de suministro en un modelo tipo Supply channel coordination in a newsvendor model with two allocation quotas

    Directory of Open Access Journals (Sweden)

    César Escalante Coterio

    2011-06-01

    Full Text Available La motivación para este trabajo proviene de un artículo escrito en 2007 por Jianli Li and Liwen Liu , quienes extienden el problema clásico del vendedor de periódicos conformando una cadena simple de suministros en el que el minorista realiza un pedido al fabricante, y si éste no satisface la demanda, tiene la posibilidad de realizar un segundo pedido dentro de un cupo limitado y condicionado por el fabricante. Ellos analizan cómo establecer un mecanismo de coordinaci´on entre las dos partes para que la ganancia esperada del sistema sea máxima. En este trabajo se amplia el modelo descrito, permitiendo que el minorista pueda recurrir a un segundo cupo de reserva al final del periodo, bajo condiciones similares, buscando optimizar la ganancia esperada del sistema. Se estudian la posibilidad de coordinaci´on del canal y el mecanismo para lograrla.The motivation for this paper arises from an article written by Jianli Li and Liwen Liu in 2007, extending the classical newsvendor model to a supply chain where the dealer, after depletion of an initial order, is given the option of a second order within an allocation quota prescribed and conditioned by the manufacturer. The paper analyzes coordination of the channel in order to improve the expected benefits of the system.This paper extends the model to allow the newsvendor a second allocation quota at the end of the period, under similar conditions. The possibilities andincentives for channel coordination are studied.

  1. Cota racial e estado: abolição do racismo ou direitos de raça? Racial quota and government: racism erradication or race rights?

    Directory of Open Access Journals (Sweden)

    Celia Maria Marinho de Azevedo

    2004-04-01

    Full Text Available O objetivo deste artigo é examinar a proposta corrente de racialização da população brasileira pelo Estado, com vistas a amparar programas de ação afirmativa para o atendimento específico daqueles que se autodenominarem negros. Analisa-se, inicialmente, o ressurgimento da noção de raça entre acadêmicos, políticos e militantes do anti-racismo, bem como as dificuldades de se delimitar quem é negro no Brasil. Em seguida, examina-se o modelo de cota racial dos Estados Unidos e seu apregoado sucesso. Por fim, busca-se avaliar até que ponto a instituição de cota racial no emprego e na universidade deveria se impor como a única opção política para aqueles que pretendem a abolição do racismo na sociedade brasileira.The objective of this article is to examine the current government proposal of "racialization" in the Brazilian population, in order to offer support to affirmative action programs that meet the specific needs of those who classify themselves as black. Firstly we focused on the revival of the notion of race among scholars, politicians, and anti-racism activists, as well as on the difficulty in determining who is black in Brazil. Next we examined the racial quota system in the United States and its proclaimed success. Finally, we assessed the extent to which the introduction of racial quota in employment and university enrollment should be imposed as the sole political option for those intending to eliminate racism in Brazilian society.

  2. Balanced sampling

    NARCIS (Netherlands)

    Brus, D.J.

    2015-01-01

    In balanced sampling a linear relation between the soil property of interest and one or more covariates with known means is exploited in selecting the sampling locations. Recent developments make this sampling design attractive for statistical soil surveys. This paper introduces balanced sampling

  3. Ensemble Sampling

    OpenAIRE

    Lu, Xiuyuan; Van Roy, Benjamin

    2017-01-01

    Thompson sampling has emerged as an effective heuristic for a broad range of online decision problems. In its basic form, the algorithm requires computing and sampling from a posterior distribution over models, which is tractable only for simple special cases. This paper develops ensemble sampling, which aims to approximate Thompson sampling while maintaining tractability even in the face of complex models such as neural networks. Ensemble sampling dramatically expands on the range of applica...

  4. Sampling designs and methods for estimating fish-impingement losses at cooling-water intakes

    International Nuclear Information System (INIS)

    Murarka, I.P.; Bodeau, D.J.

    1977-01-01

    Several systems for estimating fish impingement at power plant cooling-water intakes are compared to determine the most statistically efficient sampling designs and methods. Compared to a simple random sampling scheme the stratified systematic random sampling scheme, the systematic random sampling scheme, and the stratified random sampling scheme yield higher efficiencies and better estimators for the parameters in two models of fish impingement as a time-series process. Mathematical results and illustrative examples of the applications of the sampling schemes to simulated and real data are given. Some sampling designs applicable to fish-impingement studies are presented in appendixes

  5. Degradation of organic dyes using spray deposited nanocrystalline stratified WO3/TiO2 photoelectrodes under sunlight illumination

    Science.gov (United States)

    Hunge, Y. M.; Yadav, A. A.; Mahadik, M. A.; Bulakhe, R. N.; Shim, J. J.; Mathe, V. L.; Bhosale, C. H.

    2018-02-01

    The need to utilize TiO2 based metal oxide hetero nanostructures for the degradation of environmental pollutants like Rhodamine B and reactive red 152 from the wastewater using stratified WO3/TiO2 catalyst under sunlight illumination. WO3, TiO2 and stratified WO3/TiO2 catalysts were prepared by a spray pyrolysis method. It was found that the stratified WO3/TiO2 heterostructure has high crystallinity, no mixed phase formation occurs, strong optical absorption in the visible region of the solar spectrum, and large surface area. The photocatalytic activity was tested for degradation of Rhodamine B (Rh B) and reactive red 152 in an aqueous medium. TiO2 layer in stratified WO3/TiO2 catalyst helps to extend its absorption spectrum in the solar light region. Rh B and Reactive red 152is eliminated up to 98 and 94% within the 30 and 40 min respectively at optimum experimental condition by stratified WO3/TiO2. Moreover, stratified WO3/TiO2 photoelectrode has good stability and reusability than individual TiO2 and WO3 thin film in the degradation of Rh B and reactive red 152. The photoelectrocatalytic experimental results indicate that stratified WO3/TiO2 photoelectrode is a promising material for dye removal.

  6. Spatial Sampling of Weather Data for Regional Crop Yield Simulations

    Science.gov (United States)

    Van Bussel, Lenny G. J.; Ewert, Frank; Zhao, Gang; Hoffmann, Holger; Enders, Andreas; Wallach, Daniel; Asseng, Senthold; Baigorria, Guillermo A.; Basso, Bruno; Biernath, Christian; hide

    2016-01-01

    Field-scale crop models are increasingly applied at spatio-temporal scales that range from regions to the globe and from decades up to 100 years. Sufficiently detailed data to capture the prevailing spatio-temporal heterogeneity in weather, soil, and management conditions as needed by crop models are rarely available. Effective sampling may overcome the problem of missing data but has rarely been investigated. In this study the effect of sampling weather data has been evaluated for simulating yields of winter wheat in a region in Germany over a 30-year period (1982-2011) using 12 process-based crop models. A stratified sampling was applied to compare the effect of different sizes of spatially sampled weather data (10, 30, 50, 100, 500, 1000 and full coverage of 34,078 sampling points) on simulated wheat yields. Stratified sampling was further compared with random sampling. Possible interactions between sample size and crop model were evaluated. The results showed differences in simulated yields among crop models but all models reproduced well the pattern of the stratification. Importantly, the regional mean of simulated yields based on full coverage could already be reproduced by a small sample of 10 points. This was also true for reproducing the temporal variability in simulated yields but more sampling points (about 100) were required to accurately reproduce spatial yield variability. The number of sampling points can be smaller when a stratified sampling is applied as compared to a random sampling. However, differences between crop models were observed including some interaction between the effect of sampling on simulated yields and the model used. We concluded that stratified sampling can considerably reduce the number of required simulations. But, differences between crop models must be considered as the choice for a specific model can have larger effects on simulated yields than the sampling strategy. Assessing the impact of sampling soil and crop management

  7. The Values of Combined and Sub-Stratified Imaging Scores with Ultrasonography and Mammography in Breast Cancer Subtypes.

    Directory of Open Access Journals (Sweden)

    Tsun-Hou Chang

    Full Text Available The Breast Imaging Reporting and Data System (BI-RADS of Mammography (MG and Ultrasonography (US were equivalent to the "5-point score" and applied for combined and sub-stratified imaging assessments. This study evaluated the value of combined and sub-stratified imaging assessments with MG and US over breast cancer subtypes (BCS.Medical records of 5,037 cases having imaging-guided core biopsy, performed from 2009 to 2012, were retrospectively reviewed. This study selected 1,995 cases (1,457 benign and 538 invasive cancer having both MG and US before biopsy. These cases were categorized with the "5-point score" for their MG and US, and applied for combined and sub-stratified imaging assessments. Invasive cancers were classified on the basis of BCS, and correlated with combined and sub-stratified imaging assessments.These selected cases were evaluated by the "5-point score." MG, US, and combined and sub-stratified imaging assessments all revealed statistically significant (P < 0.001 incidence of malignancy. The sensitivity was increased in the combined imaging score (99.8%, and the specificity was increased in the sub-stratified combined score (75.4%. In the sub-stratified combined imaging assessment, all BCS can be classified with higher scores (abnormality hierarchy, and luminal B subtype showed the most salient result (hierarchy: higher, 95%; lower, 5%.Combined and sub-stratified imaging assessments can increase sensitivity and specificity of breast cancer diagnosis, respectively, and Luminal B subtype shows the best identification by sub-stratified combined imaging scoring.

  8. Analysis of flame propagation phenomenon in simplified stratified charge conditions; Tanjunkasareta sojo kyukiba ni okeru kaen denpa gensho no kansatsu

    Energy Technology Data Exchange (ETDEWEB)

    Moriyoshi, Y; Morikawa, H [Chiba University, Chiba (Japan); Kamimoto, T [Tokyo Institute of Technology, Tokyo (Japan)

    1997-10-01

    Since the local inhomogeneity of mixture concentration inside the cylinder affects the combustion characteristics, a basic research on combustion phenomenon in stratified charge conditions is required. The authors have made experiments with a constant-volume chamber, which can simulate an idealized stratified charge field by using a removable partition, to obtain the combustion characteristics. Also, numerical calculations are made using some combustion models. As a result, the important feature that the combustion speed is faster in stratified condition than in homogeneous condition can be predicted by the two-step reaction model. 4 refs., 8 figs.

  9. Rapid shelf-wide cooling response of a stratified coastal ocean to hurricanes.

    Science.gov (United States)

    Seroka, Greg; Miles, Travis; Xu, Yi; Kohut, Josh; Schofield, Oscar; Glenn, Scott

    2017-06-01

    Large uncertainty in the predicted intensity of tropical cyclones (TCs) persists compared to the steadily improving skill in the predicted TC tracks. This intensity uncertainty has its most significant implications in the coastal zone, where TC impacts to populated shorelines are greatest. Recent studies have demonstrated that rapid ahead-of-eye-center cooling of a stratified coastal ocean can have a significant impact on hurricane intensity forecasts. Using observation-validated, high-resolution ocean modeling, the stratified coastal ocean cooling processes observed in two U.S. Mid-Atlantic hurricanes were investigated: Hurricane Irene (2011)-with an inshore Mid-Atlantic Bight (MAB) track during the late summer stratified coastal ocean season-and Tropical Storm Barry (2007)-with an offshore track during early summer. For both storms, the critical ahead-of-eye-center depth-averaged force balance across the entire MAB shelf included an onshore wind stress balanced by an offshore pressure gradient. This resulted in onshore surface currents opposing offshore bottom currents that enhanced surface to bottom current shear and turbulent mixing across the thermocline, resulting in the rapid cooling of the surface layer ahead-of-eye-center. Because the same baroclinic and mixing processes occurred for two storms on opposite ends of the track and seasonal stratification envelope, the response appears robust. It will be critical to forecast these processes and their implications for a wide range of future storms using realistic 3-D coupled atmosphere-ocean models to lower the uncertainty in predictions of TC intensities and impacts and enable coastal populations to better respond to increasing rapid intensification threats in an era of rising sea levels.

  10. Identification of distinct layers within the stratified squamous epithelium of the adult human true vocal fold.

    Science.gov (United States)

    Dowdall, Jayme R; Sadow, Peter M; Hartnick, Christopher; Vinarsky, Vladimir; Mou, Hongmei; Zhao, Rui; Song, Phillip C; Franco, Ramon A; Rajagopal, Jayaraj

    2015-09-01

    A precise molecular schema for classifying the different cell types of the normal human vocal fold epithelium is lacking. We hypothesize that the true vocal fold epithelium has a cellular architecture and organization similar to that of other stratified squamous epithelia including the skin, cornea, oral mucosa, and esophagus. In analogy to disorders of the skin and gastrointestinal tract, a molecular definition of the normal cell types within the human vocal fold epithelium and a description of their geometric relationships should serve as a foundation for characterizing cellular changes associated with metaplasia, dysplasia, and cancer. Qualitative study with adult human larynges. Histologic sections of normal human laryngeal tissue were analyzed for morphology (hematoxylin and eosin) and immunohistochemical protein expression profile, including cytokeratins (CK13 and CK14), cornified envelope proteins (involucrin), basal cells (NGFR/p75), and proliferation markers (Ki67). We demonstrated that three distinct cell strata with unique marker profiles are present within the stratified squamous epithelium of the true vocal fold. We used these definitions to establish that cell proliferation is restricted to certain cell types and layers within the epithelium. These distinct cell types are reproducible across five normal adult larynges. We have established that three layers of cells are present within the normal adult stratified squamous epithelium of the true vocal fold. Furthermore, replicating cell populations are largely restricted to the parabasal strata within the epithelium. This delineation of distinct cell populations will facilitate future studies of vocal fold regeneration and cancer. N/A. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

  11. Mortality in perforated peptic ulcer patients after selective management of stratified poor risk cases.

    Science.gov (United States)

    Rahman, M Mizanur; Islam, M Saiful; Flora, Sabrina; Akhter, S Fariduddin; Hossain, Shahid; Karim, Fazlul

    2007-12-01

    Perforated peptic ulcer disease continues to inflict high morbidity and mortality. Although patients can be stratified according to their surgical risk, optimal management has yet to be described. In this study we demonstrate a treatment option that improves the mortality among critically ill, poor risk patients with perforated peptic ulcer disease. In our study, two series were retrospectively reviewed: group A patients (n = 522) were treated in a single surgical unit at the Dhaka Medical College Hospital, Dhaka, Bangladesh during the 1980s. Among them, 124 patients were stratified as poor risk based on age, delayed presentation, peritoneal contamination, and coexisting medical problems. These criteria were the basis for selecting a group of poor risk patients (n = 84) for minimal surgical intervention (percutaneous peritoneal drainage) out of a larger group of patients, group B (n = 785) treated at Khulna Medical College Hospital during the 1990s. In group A, 479 patients underwent conventional operative management with an operative mortality of 8.97%. Among the 43 deaths, 24 patients were >60 years of age (55.8%), 12 patients had delayed presentation (27.9%), and 7 patients were in shock or had multiple coexisting medical problems (16.2%). In group B, 626 underwent conventional operative management, with 26 deaths at a mortality rate of 4.15%. Altogether, 84 patients were stratified as poor risk and were managed with minimal surgical intervention (percutaneous peritoneal drainage) followed by conservative treatment. Three of these patients died with an operative mortality of 3.5%. Minimal surgical intervention (percutaneous peritoneal drainage) can significantly lower the mortality rate among a selected group of critically ill, poor risk patients with perforated peptic ulcer disease.

  12. Stratified premedication strategy for the prevention of contrast media hypersensitivity in high-risk patients.

    Science.gov (United States)

    Lee, Suh-Young; Yang, Min Suk; Choi, Young-Hoon; Park, Chang Min; Park, Heung-Woo; Cho, Sang Heon; Kang, Hye-Ryun

    2017-03-01

    Although the severity of hypersensitivity reactions to iodinated contrast media varies, it is well correlated with the severity of recurrent reactions; however, prophylaxis protocols are not severity-stratified. To assess the outcomes of tailored prophylaxis according to the severity of hypersensitivity reactions to iodinated contrast media. Our premedication protocols were stratified based on the severity of previous reactions: (1) 4 mg of chlorpheniramine for mild reactions, (2) adding 40 mg of methylprednisolone for moderate reactions, and (3) adding multiple doses of 40 mg of methylprednisolone for severe index reactions. Cases of reexposure in patients with a history of hypersensitivity reactions were routinely monitored and mandatorily recorded. Among a total of 850 patients who underwent enhanced computed tomography after severity-tailored prophylaxis, breakthrough reactions occurred in 17.1%, but most breakthrough reactions (89.0%) were mild and did not require medical treatment. Additional corticosteroid use did not reduce the breakthrough reaction rate in cases with a mild index reaction (16.8% vs 17.2%, P = .70). However, underpremedication with a single dose of corticosteroid revealed significantly higher rates of breakthrough reaction than did double doses of corticosteroid in cases with a severe index reaction (55.6% vs 17.4%, P = .02). Changing the iodinated contrast media resulted in an additional reduction of the breakthrough reaction rate overall (14.9% vs 32.1%, P = .001). In a total severity-based stratified prophylaxis regimens and changing iodinated contrast media can be considered in patients with a history of previous hypersensitivity reaction to iodinated contrast media to reduce the risk of breakthrough reactions. Copyright © 2016 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  13. Assessment of horizontal in-tube condensation models using MARS code. Part I: Stratified flow condensation

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Seong-Su [Department of Engineering Project, FNC Technology Co., Ltd., Bldg. 135-308, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Department of Nuclear Engineering, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Hong, Soon-Joon, E-mail: sjhong90@fnctech.com [Department of Engineering Project, FNC Technology Co., Ltd., Bldg. 135-308, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Park, Ju-Yeop; Seul, Kwang-Won [Korea Institute of Nuclear Safety, 19 Kuseong-dong, Yuseong-gu, Daejon (Korea, Republic of); Park, Goon-Cherl [Department of Nuclear Engineering, Seoul National University, Gwanak-gu, Seoul 151-744 (Korea, Republic of)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer This study collected 11 horizontal in-tube condensation models for stratified flow. Black-Right-Pointing-Pointer This study assessed the predictive capability of the models for steam condensation. Black-Right-Pointing-Pointer Purdue-PCCS experiments were simulated using MARS code incorporated with models. Black-Right-Pointing-Pointer Cavallini et al. (2006) model predicts well the data for stratified flow condition. Black-Right-Pointing-Pointer Results of this study can be used to improve condensation model in RELAP5 or MARS. - Abstract: The accurate prediction of the horizontal in-tube condensation heat transfer is a primary concern in the optimum design and safety analysis of horizontal heat exchangers of passive safety systems such as the passive containment cooling system (PCCS), the emergency condenser system (ECS) and the passive auxiliary feed-water system (PAFS). It is essential to analyze and assess the predictive capability of the previous horizontal in-tube condensation models for each flow regime using various experimental data. This study assessed totally 11 condensation models for the stratified flow, one of the main flow regime encountered in the horizontal condenser, with the heat transfer data from the Purdue-PCCS experiment using the multi-dimensional analysis of reactor safety (MARS) code. From the assessments, it was found that the models by Akers and Rosson, Chato, Tandon et al., Sweeney and Chato, and Cavallini et al. (2002) under-predicted the data in the main condensation heat transfer region, on the contrary to this, the models by Rosson and Meyers, Jaster and Kosky, Fujii, Dobson and Chato, and Thome et al. similarly- or over-predicted the data, and especially, Cavallini et al. (2006) model shows good predictive capability for all test conditions. The results of this study can be used importantly to improve the condensation models in thermal hydraulic code, such as RELAP5 or MARS code.

  14. Rapid shelf‐wide cooling response of a stratified coastal ocean to hurricanes

    Science.gov (United States)

    Miles, Travis; Xu, Yi; Kohut, Josh; Schofield, Oscar; Glenn, Scott

    2017-01-01

    Abstract Large uncertainty in the predicted intensity of tropical cyclones (TCs) persists compared to the steadily improving skill in the predicted TC tracks. This intensity uncertainty has its most significant implications in the coastal zone, where TC impacts to populated shorelines are greatest. Recent studies have demonstrated that rapid ahead‐of‐eye‐center cooling of a stratified coastal ocean can have a significant impact on hurricane intensity forecasts. Using observation‐validated, high‐resolution ocean modeling, the stratified coastal ocean cooling processes observed in two U.S. Mid‐Atlantic hurricanes were investigated: Hurricane Irene (2011)—with an inshore Mid‐Atlantic Bight (MAB) track during the late summer stratified coastal ocean season—and Tropical Storm Barry (2007)—with an offshore track during early summer. For both storms, the critical ahead‐of‐eye‐center depth‐averaged force balance across the entire MAB shelf included an onshore wind stress balanced by an offshore pressure gradient. This resulted in onshore surface currents opposing offshore bottom currents that enhanced surface to bottom current shear and turbulent mixing across the thermocline, resulting in the rapid cooling of the surface layer ahead‐of‐eye‐center. Because the same baroclinic and mixing processes occurred for two storms on opposite ends of the track and seasonal stratification envelope, the response appears robust. It will be critical to forecast these processes and their implications for a wide range of future storms using realistic 3‐D coupled atmosphere‐ocean models to lower the uncertainty in predictions of TC intensities and impacts and enable coastal populations to better respond to increasing rapid intensification threats in an era of rising sea levels. PMID:28944132

  15. Laser sampling

    International Nuclear Information System (INIS)

    Gorbatenko, A A; Revina, E I

    2015-01-01

    The review is devoted to the major advances in laser sampling. The advantages and drawbacks of the technique are considered. Specific features of combinations of laser sampling with various instrumental analytical methods, primarily inductively coupled plasma mass spectrometry, are discussed. Examples of practical implementation of hybrid methods involving laser sampling as well as corresponding analytical characteristics are presented. The bibliography includes 78 references

  16. Suspected survivor bias in case-control studies: stratify on survival time and use a negative control.

    Science.gov (United States)

    van Rein, Nienke; Cannegieter, Suzanne C; Rosendaal, Frits R; Reitsma, Pieter H; Lijfering, Willem M

    2014-02-01

    Selection bias in case-control studies occurs when control selection is inappropriate. However, selection bias due to improper case sampling is less well recognized. We describe how to recognize survivor bias (i.e., selection on exposed cases) and illustrate this with an example study. A case-control study was used to analyze the effect of statins on major bleedings during treatment with vitamin K antagonists. A total of 110 patients who experienced such bleedings were included 18-1,018 days after the bleeding complication and matched to 220 controls. A protective association of major bleeding for exposure to statins (odds ratio [OR]: 0.56; 95% confidence interval: 0.29-1.08) was found, which did not become stronger after adjustment for confounding factors. These observations lead us to suspect survivor bias. To identify this bias, results were stratified on time between bleeding event and inclusion, and repeated for a negative control (an exposure not related to survival): blood group non-O. The ORs for exposure to statins increased gradually to 1.37 with shorter time between outcome and inclusion, whereas ORs for the negative control remained constant, confirming our hypothesis. We recommend the presented method to check for overoptimistic results, that is, survivor bias in case-control studies. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. A comparison of dental caries levels in two communities with different oral health prevention strategies stratified in different social classes.

    Science.gov (United States)

    Sagheri, Darius; McLoughlin, Jacinta; Clarkson, John J

    2007-01-01

    To compare dental caries levels of schoolchildren stratified in different social classes whose domestic water supply had been fluoridated since birth (Dublin) with those living in an area where fluoridated salt was available (Freiburg). A representative, random sample of twelve-year-old children was examined and dental caries was recorded using World Health Organization criteria. A total of 699 twelve-year-old children were examined, 377 were children in Dublin and 322 in Freiburg. In Dublin the mean decayed, missing, and filled permanent teeth (DMFT) was 0.80 and in Freiburg it was 0.69. An examination of the distribution of the DMFT score revealed that its distribution is highly positively skewed. For this reason this study provides summary analyses based on medians and inter-quartile range and nonparametric rank sum tests. In both cities caries levels of children in social class 1 (highest) were considerably lower when compared with the other social classes regardless of the fluoride intervention model used. The caries levels showed a reduced disparity between children in social class 2 (medium) and 3 (lowest) in Dublin compared with those in social class 2 and 3 in Freiburg. The evidence from this study confirmed that water fluoridation has reduced the gap in dental caries experience between medium and lower social classes in Dublin compared with the greater difference in caries experience between the equivalent social classes in Freiburg. The results from this study established the important role of salt fluoridation where water fluoridation is not feasible.

  18. Quality of life in survivors of hematological malignancies stratified by cancer type, time since diagnosis and stem cell transplantation.

    Science.gov (United States)

    Esser, Peter; Kuba, Katharina; Mehnert, Anja; Johansen, Christoffer; Hinz, Andreas; Lordick, Florian; Götze, Heide

    2018-06-01

    Quality of life (QoL) has become an important tool to guide decision making in oncology. Given the heterogeneity among hematological cancer survivors, however, clinicians need comparative data across different subsets. This study recruited survivors of hematological malignancies (≥ 2.5 years after diagnosis) from two German cancer registries. QoL was assessed with the EORTC QLQ-C30. The sample was stratified by cancer type, time since diagnosis, treatment with stem cell transplantation (SCT) and type of SCT. First, levels of QoL were compared across subsamples when controlling for several covariates. Second, we contrasted subsamples with gender- and age-matched population controls obtained from the general population. Of 2001 survivors contacted by mail, 922 (46%) participated in the study. QoL did not significantly differ between the subsamples. All subsamples scored significantly lower in functioning and significantly higher in symptom burden compared to population controls (all p < .001). Almost all of these group effects reached clinically meaningful sizes (Cohen's d ≥ .5). Group differences in global health/QoL were mostly non-significant. Hematological cancer survivors are associated with practically relevant impairments irrespective of differences in central medical characteristics. Nevertheless, survivors seem to evaluate their overall situation as relatively well. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  19. Approximate solutions and error bounds for the wave equation in a stratified ionosphere with turning points

    International Nuclear Information System (INIS)

    Nalesso, G.F.; Jacobson, A.R.

    1991-01-01

    A solution to the problem of a plane electromagnetic wave traveling parallel to a constant magnetic field in a horizontally stratified ionosphere was developed assuming that the permittivity of the medium can be represented as the sum of an unperturbed component and a perturbed component. The method is successfully applied to the case of a linearly varying permittivity of a lossless ionosphere with a superimposed Gaussian perturbing term. The feasibility of applying the method in the presence of an odd number of turning points is discussed. 13 refs

  20. Design of a high-performance rotary stratified-charge research aircraft engine

    Science.gov (United States)

    Jones, C.; Mount, R. E.

    1984-01-01

    The power section for an advanced rotary stratified-charge general aviation engine has been designed under contract to NASA. The single-rotor research engine of 40 cubic-inches displacement (RCI-40), now being procured for test initiation this summer, is targeted for 320 T.O. horse-power in a two-rotor production engine. The research engine is designed for operating on jet-fuel, gasoline or diesel fuel and will be used to explore applicable advanced technologies and to optimize high output performance variables. Design of major components of the engine is described in this paper.