The regional impacts of ozone on corn, wheat, soybean, and peanut crops are estimated by using dose-response functions to relate ambient maximum 7 h/d seasonal ozone concentrations to crop productivity data. Linear dose-response functions were developed from open-top field chamber studies. It was assumed that the limited number of cultivars and growing conditions available for the analysis were representative of major agricultural regions. Hourly ozone data were selected to represent rural concentrations and used to calculate maximum 7-h/d average values. Seasonal ozone averages for counties were extrapolated from approximately 300 monitoring sites. Results must be interpreted with knowledge of these assumptions and sources of uncertainty. Impacts are calculated for county units for the conterminous United States with maps showing patterns and tables summarizing the potential magnitude of ozone effects ...
This document deals with the couplings between the W boson and Z and gamma particles. WWZ and WW{gamma} vertex are predicted by the electroweak theory based on the symmetry group SU(2){sub L}*U(1){sub Y}, their existence is confirmed by the measurement of the production cross-section of W pairs at LEP. The effective values of the couplings are modified by the introduction of standard model particle loops at the vertex level, the impact on the coupling value is assessed to reach 10{sup -3}. These loops can also include beyond-the-standard-model particles, their impact is in the magnitude order of 10{sup -3} for most models. The fully description of these loops requires the values of 14 complex parameters whose measurement will give information about the existence of new particles. Nevertheless the number of events at LEP is not sufficient to measure all the parameters simultaneously. As a consequence the analysis is limited ...
High and volatile natural gas prices have increasingly led to calls for investments in renewable energy. One line of argument is that deployment of these resources may lead to reductions in the demand for and price of natural gas. Many recent US-based modeling studies have demonstrated that this effect could provide significant consumer savings. In this article we evaluate these studies, and benchmark their findings against economic theory, other modeling results, and a limited empirical literature. We find that many uncertainties remain regarding the absolute magnitude of this effect, and that the reduction in natural gas prices may not represent an increase in aggregate economic wealth. Nonetheless, we conclude that many of the studies of the impact of renewable energy on natural gas prices appear to have represented this effect within reason, given current knowledge. These studies specifically suggest that a 1% reduction ...
High and volatile natural gas prices have increasingly led to calls for investments in renewable energy. One line of argument is that deployment of these resources may lead to reductions in the demand for and price of natural gas. Many recent US-based modeling studies have demonstrated that this effect could provide significant consumer savings. In this article we evaluate these studies, and benchmark their findings against economic theory, other modeling results, and a limited empirical literature. We find that many uncertainties remain regarding the absolute magnitude of this effect, and that the reduction in natural gas prices may not represent an increase in aggregate economic wealth. Nonetheless, we conclude that many of the studies of the impact of renewable energy on natural gas prices appear to have represented this effect within reason, given current knowledge. These studies specifically suggest that a 1% reduction ...
Estimates of climate change impacts are plague with uncertainties from many physical, biological, and social-economic processes. Among the urgent research priorities, more comprehensive assessments of impacts that better represent the uncertainties are needed. Here, we develop a new super-ensemble-based probabilistic projection approach to account for the uncertainties from CO2 emission scenarios, climate change scenarios, and biophysical processes in impact assessment model. We demonstrate the approach in addressing the probabilistic changes of maize production in the North China Plain in future. The new process-based general crop model, MCWLA [Tao, F., Yokozawa, M. Zhang, Z., 2009. Modelling the impacts of weather and climate variability on crop productivity over a large area: a new proc...
Technologies and practices that recover energy and materials from municipal solid waste present a technically and economically viable alternative to sanitary landfills and other solid waste disposal methods. However, community planners considering resource recovery should be aware of the potential environmental impacts of proposed projects. To assess these impacts, a planner should: identify the most significant types of impacts; establish boundaries beyond which impacts are not significant; characterize the environment as it would exist without the proposed project over the project's lifetime; predict the magnitude, and the distribution over time and space, of potential impacts; and relate the magnitude of predicted impacts to a scale of significance that will allow environmental values to be considered in ...
The impacts of climate change on crop productivity are often assessed using simulations from a numerical climate model as an input to a crop simulation model. The precision of these predictions reflects...Full Text Available
BackgroundInsurance coverage of tobacco cessation medications increases their use and reduces smoking prevalence in a population. However, uncertainty about the impact of this coverage...Full Text Available
This paper presents the results of a model for the impact of potential contamination produced by radionuclide leaking due to long-term physical, chemical and hydrogeological processes occurring in a LILW repository and in the natural environment. The analysis contains a deterministic and also a probabilistic approach for uncertainty assessment. The input function, i.e., the source term was evaluated by using AMBER code and the entire analysis was accomplished by using GOLDSIM, a powerful tool to support probabilistic simulation in management and decision-making in engineering and science. The results obtained were compared to previous simulations and uncertainty analyses (FEHM). (authors)
We combine a limited number of accurately measured transition frequencies in hydrogen and deuterium, recent quantum electrodynamics (QED) calculations, and, as an essential additional ingredient, a generalized least-squares analysis, to obtain precise and optimal predictions for hydrogen and deuterium transition frequencies. Some of the predicted transition frequencies have relative uncertainties more than an order of magnitude smaller than that of the g-factor of the electron, which was previously the most accurate prediction of QED.
To assist in attaining the HSE's objective of providing perspective and focus for Safety Case Assessment, a generic model of the structural design process for the foundations of pile supported fixed steel structures has been developed. Interfaces between the foundation design team and other stakeholders have been identified and assessments made of both the magnitude and the potential significance of the uncertainties associated with key elements of the design process. (author)
Thirty years ago, in 1967, the new definition of the second based on a quantum phenomenon, the hyperfine splitting of the groundstate of the "1"3"3Cs atom, was passed by the 13th General Conference on Weight and Measure. What followed was a fascinating improvement of the performance of caesium clocks which is still pursued. Their total uncertainty could be reduced, until 1995, by 4 orders of magnitude. With the development of the so-called fountain clocks, another factor of ten is within reach. (orig.)
A reliability approach for probabilistic modeling of one-dimensional non-reactive and reactive transport in porous media provides two important quantitative results: (1) an estimate of the probability that dimensionless concentration equals or exceeds some specified level and, (2) the sensitivity of the probabilistic outcome to likely changes in each uncertain variable. The reliability approach is particularly attractive because it can incorporate various marginal probability density functions (PDF) for any of the uncertain variables. In this work uncertain variables include: groundwater flow velocity, diffusion coefficient, dispersivity, distribution coefficient, porosity and bulk density. The primary objective is to examine how the probabilistic outcome is influenced by choice of marginal PDF, correlation and magnitude of uncertainty for the variables. Because little information exists concerning the statistical characteristics of these ...
Potential maximum radiation dose rates over a 1,000-year time horizon were calculated for exposure to the decontaminated concrete removed from the 183-H Solar Evaporation Basins at the Hanford Site, Richland, Washington. The RESRAD computer code, Version 5.62, which implements the methodology described in the US Department of Energy`s manual for developing residual radioactive material guidelines, was used in this evaluation. Currently, the concrete is not being used. Four potential exposure scenarios were developed for the land area where the decontaminated concrete will be stored. In Scenario A industrial use of the land is assumed; in Scenario B recreational use of the land is assumed; in Scenario C residential use of the land is assumed; and in Scenario D (a plausible but unlikely land-use scenario), the presence of a subsistence farmer in the immediate vicinity of the land is assumed. For Scenarios A and B, water used for drinking is assumed to be surface water from the Columbia ...
This report to the Nuclear Regulatory Commission (NRC) describes the development and application of a methodology to systematically and quantitatively assess predictive uncertainty in groundwater flow and transport modeling that considers the combined impact of hydrogeologic uncertainties associated with the conceptual-mathematical basis of a model, model parameters, and the scenario to which the model is applied. The methodology is based on a n extension of a Maximum Likelihood implementation of Bayesian Model Averaging. Model uncertainty is represented by postulating a discrete set of alternative conceptual models for a site with associated prior model probabilities that reflect a belief about the relative plausibility of each model based on its apparent consistency with available knowledge and data. Posterior model probabilities are computed and parameter uncertainty is estimated ...
We examine the short-term price behaviour of three, size-conditioned Indian stock market indices, in response to informational shocks. A standard mean-adjusted returns model as well as the GJR-GARCH specification point towards underreaction to negative events in the medium and small capitalization indices. Also, the pre-event coefficients are generally negative and statistically significant, regardless of the sign of the shock, thus ruling out information leaks. We uncover a stable abnormal volatility pattern which increases monotonically a few days before the shock before suddenly decreasing in magnitude on the event day and beyond. We suggest uncertainty avoidance as a potential explanation of these features. The results are fairly robust across alternative event selection procedures, ti...
Dark Matter annihilation (DMA) may yield an excess of gamma rays and antimatter particles, like antiprotons and positrons, above the background from cosmic ray interactions. Several signatures, ranging from the positron excess, as observed by HEAT, AMS-01 and PAMELA, the gamma ray excess, as observed by the EGRET spectrometer, the WMAP-haze, and constraints from antiprotons, as observed by CAPRICE, BESS and PAMELA, have been discussed in the literature. Unfortunately, the different signatures all lead to different WIMP masses, indicating that at least some of these interpretations are likely to be incorrect. Here we review them and discuss their relative merits and uncertainties. New x-ray data from ROSAT suggests non-negligible convection in our Galaxy, which leads to an order of magnitudeuncertainty in the yield of charged particles from DMA, since even a rather small convection will let drift the charged particles in ...
There is now a scientific consensus that current rates of accumulation of greenhouses gases in the atmosphere will result in significant global warming and climate change. These changes are likely to have important impacts on a wide range of human activities and the natural environment. There has now been a considerable weight of literature published on the impacts of global warming, much of it very recent. This report seeks to summarise the important results, to analyse the uncertainties and to make a preliminary analysis of the feasibility of monetarising these environmental costs. The impacts of global warming are divided into ten major categories: agriculture, forests and forestry, terrestrial ecosystems and biodiversity, hydrology and water resources, sea level rise and coastal zones, energy, infrastructure/transport/industry, human health and air quality, oceans, and cryospheric ...
A probability-based approach is presented as the integration of probabilistic methods and deterministic modelling based on the finite element method. An existing finite element software package was linked to an existing probabilistic package to analyse the complex mechanics that occur during the transient non-linear analysis of impact problems. This methodology is applied to a pipe whip analysis of a group-distribution-header, which results from a guillotine break, and subsequent impact with the adjacent building wall; this is a postulated accident for the Ignalina Nuclear Power Plant RBMK-1500 reactors. The uncertainties of material properties, component geometry data and loads were taken into consideration. The probabilities of failure of the impacted header and of the header support-wall were estimated given uncertainties in material properties, geometrical parameters and ...
The objective of this work is to study greenhouse gas emissions and sinks and their greenhouse impact as a function of time. The greenhouse impact is expressed in terms of global average radiative forcing, which measures the perturbation in the Earth`s radiation budget. Radiative forcing is calculated on the basis of the concentration changes of the greenhouse gases and the radiation absorption properties of the gases. It takes into account the relatively slow changes in the concentrations due to natural removal and transformation processes and also allows a comparison of the impact of various greenhouse gases and their possible control options as a function of time. In addition to the applications mentioned above, the anthropogenic greenhouse gas emission histories of Nordic countries have been estimated, and the radiative forcing caused by them has been calculated with REFUGE. The dynamic impact of ...
Synthetic fuels differ in the nature and order of magnitude of the environmental impacts associated with their production. Some types pose much more intractable problems, with oil shale leading the list. Perceptions of the difficulty of these environmental problems will continue to shift over time as more research and experimentation is done. It is critical that the development of synthetic fuels move slowly and deliberately so as not to get ahead of researched solutions nor to create environmental burdens that outweigh the social benefits of increased energy production. The Synthetic Fuels Corporation is taking the opposite approach in dispensing funds to all takers. 65 references.
First results on the effects of strain on transient enhanced diffusion and deactivation of As-implanted ultrashallow junctions are presented. A significant effect of strain on the magnitude and timescale of transient enhanced diffusion is observed, which is consistent with the stabilization of interstitial-type defects by tensile strain. Our results show no significant impact of strain on As electrical activity during the deactivation timescale accessed in this study.
The probability of damage and the potential resulting hazards are analyzed for a representative rail shipping container for three severe rail accident scenarios. The scenarios are: (1) the rupture of closure bolts and resulting opening of closure lid due to a severe impact, (2) the puncture of container by an impacting rail-car coupler, and (3) the yielding of container due to side impact on a rigid uneven surface. The analysis results indicate that scenario 2 is a physically unreasonable event while the probabilities of a significant loss of containment in scenarios 1 and 3 are extremely small. Before assessing the potential risk for the last two scenarios, the uncertainties in predicting complex phenomena for rare, high- consequence hazards needs to be addressed using a rigorous methodology.
The main purpose of the study on the title subject is to gain insight into the strategic options to optimize energy production from waste processing in the Netherlands in the long term. The developed optimization model will be used by the Dutch Ministry of Public Health, Spatial Planning en Environment (VROM) for scenarios to calculate and determine expectations and uncertainties in the development of waste processing in the Netherlands. Attention is paid to (1) the impact of present and future technology on the costs and energetic efficiency of waste processing, (2) several techniques for the generation of electricity and heat, the production of fuels, and recycling, (3) the impact of scale (capacity) on costs and energetic efficiency of waste processing installations, and (4) the impact of transport and heat distribution. The time frame is the year 2020. 66 refs.
The Office of Environmental Management's (EM) Roadmap, U.S. Department of Energy--Office of Environmental Management Engineering & Technology Roadmap (Roadmap), defines the Department's intent to reduce the technical risk and uncertainty in its cleanup programs. The unique nature of many of the remaining facilities will require a strong and responsive engineering and technology program to improve worker and public safety, and reduce costs and environmental impacts while completing the cleanup program. The technical risks and uncertainties associated with cleanup program were identified through: (1) project risk assessments, (2) programmatic external technical reviews and technology readiness assessments, and (3) direct site input. In order to address these needs, the technical risks and uncertainties were compiled and divided into the program areas of: Waste Processing, Groundwater ...
In this paper, the performance of customer-owned distributed generation (DG) units is quantified from different perspectives through an uncertainty study. A Monte Carlo-based method is applied to assess the stochastic operation of the customer-owned DG units in the power distribution system. Several cases are studied to analyze the impact on system performance of using such generators, with the emphasis on benefits. The results of the studied cases show that proper operation of customer-owned DG units placed close to significant consumption centers offers several benefits which lead to significant energy savings and improvement in the performance indices while maintaining the cost-effectiveness. Furthermore, based on the energy demand, different electricity price scenarios considering a co...
In this article we evaluate a US Forest Service plan to mitigate damages from an invasive insect on public, forested land. We develop a dynamic model of infestation and control to explicitly account for biological interactions, baseline conditions, and uncertainty, thus creating a more complete picture of policy impacts than a static cost benefit analysis could provide. We combine the results of the dynamic model with an empirical study of nonmarket forest benefits to create a bioeconomic model of ecosystem management. Estimating the empirical model in a Bayesian framework allows us to treat the economic coefficients of the dynamic model as random variables. We specify distributions for the biological parameters and examine the effects of both biological and economic uncertainty on the pre...
Existing test procedures for measuring and rating thermal performance require the determination of the angular response of collectors in order to account for nonnormal incident beam irradiance. Angular response measurements for four different types of collectors, each type tested by three different laboratories, are presented and analyzed. Substantial differences, both within and between laboratories, are reported for the same type collectors. An analysis of the measurement procedure shows that experimentally determined angular response parameters are subject to relatively large uncertainties. The problem results to a large extent from measuring collector efficiencies at non-normal incident angles where measurement uncertainty is of the same order of magnitude as the efficiency reduction attributable to these off-normal angles. Other factors which can affect angular response measurements and the method of correlating ...
One of inherent characteristics of CANDU reactor is positive void reactivity in contrast to other pressurized light water reactors. During the large break loss of coolant accident, power pulse will be occurred during short time of early phase of accident due to positive void reactivity. However the duration of this power pulse is short, energy due to power pulse would be accumulated in the cladding material and will affect the peak cladding temperature or number of failed fuel elements. Recently, Canadian Nuclear Safety Commission (CNSC) indicated that the amount of void reactivity might be larger than the assumed values in safety analysis and this indication was based on the experimental data from ZED-2 facility. Based on that, the estimation of uncertainties due to the void reactivity during LBLOCA is the most important issue for CANDU safety analysis. In this study, a framework of uncertainty evaluation methodology for CANDU void reactivity ...
The long-lived nuclides of the americium curium elements are of interest for their use in certain safeguard applications and for nuclear reactor burnup studies in waste management. Recommended values are presented for /sup 241,242m,243/Am, and for /sup 242,243,244,245,246,247,248,250/Cm. These values result from a consistent evaluation of all these half-lives. These preliminary estimates were presented earlier. The uncertainties are provided at the 95% confidence limit for each of the recommended values. It will be noted that many of the recommended errors considerably exceed errors quoted by individual authors in their publication, by up to an order of magnitude, e.g., the total half-life of /sup 242,246,248/Cm and the spontaneous fission half-life of /sup 244/Cm. 65 refs., 18 tabs.
Dark Matter annihilation (DMA) may yield an excess of gamma rays and antimatter particles, like antiprotons and positrons, above the background from cosmic ray interactions. The excess of diffuse Galactic Gamma Rays from EGRET shows all the features expected from DMA. The new precise measurements of the antiproton and positron fractions from PAMELA are compared with the EGRET excess. It is shown that the charged particles are strongly dependent on the propagation model used. The usual propagation models with isotropic propagation models are incompatible with the recently observed convection in our Galaxy. Convection leads to an order of magnitudeuncertainty in the yield of charged particles from DMA, since even a rather small convection will let drift the charged particles in the halo to outer space. It is shown that such anisotropic propagation models including convection prefer a contribution from DMA for the antiprotons, but the rise in the ...
This paper discusses the link between R&D and productivity across the European industrial and service sectors. The empirical analysis is based on both the European sectoral OECD data and on a unique micro-longitudinal database consisting of 532 top European R&D investors. The main conclusions are as follows. First, the R&D stock has a significant positive impact on labor productivity; this general result is largely consistent with previous literature in terms of the sign, the significance, and the magnitude of the estimated coefficients. More interestingly, both at sectoral and firm levels the R&D coefficient increases monotonically (both in significance and magnitude) when we move from the low-tech to the medium- and high-tech sectors. This outcome means that corporate R&D investment is m...
The present study treats only the collective risk of ex-utero leukaemia associated with the routine releases of the nuclear industrial installations of the North Cotentin (0.0009 cases over the considered period) the uncertainty on the contribution to the collective risk of the incidents and the accidents of the nuclear installations (notably the drilling of the pipe of release in sea arisen in 1979-1980 and the fire of the waste silo on January 6. 1981, for the reprocessing plant of La Hague has not been considered. Only 45% of the risk are taken into account by the study. Every calculated value remains very inferior to the number of leukemia cases observed (4 cases observed for two expected cases) and to the risk of radioinduced leukemia any merged exposure sources, that is to say 0.84 cases. It appears thus not very probable that the nuclear installations of the North - Cotentin can explain the tendency to the excess of observed leukaemia. The limits of the ...
The objective of this paper is to analyze the implications of varying degrees of financial openness for the impact of technology shocks on a real, small open economy with financial and informational frictions. Aggregate fluctuations and propagation mechanisms under increasing financial openness are investigated in a dynamic, stochastic, general equilibrium framework in the case of positive technology shocks. The imperfections in the economy in the form of informational asymmetries among the agents and uncertainty in the production process necessitate financial intermediation and collateralized borrowing in the economy. The reason to abstract from money in the setup of the framework is to be able to concentrate on the real implications of increasing financial openness for the effect of tech...
This research investigates the impact of national culture and several institutional factors on the safety performance of society and establishes statistically significant relationships between those variables. As expected, the research results reveal that some cultural variables such as uncertainty avoidance, gender orientation and institutional variables such as the degree of law avoidance can directly influence the safety performance of the society. The findings also support the inverted u-curve (Safety Kuznet curve) hypothesis indicating even if we expect a negative trend at the beginning stage of industrialization, we can expect a positive trend in safety performance as their income level continues to improve beyond a certain point.
The aim of the safety calculation is to quantify through numerical modelling the radiological impact (molar flow, human dose) of a potential repository for radioactive waste on the Meuse/Haute Marne site at Bure. A selection process is underway for safety scenarios and their phenomenological and numerical conceptual models upstream from the safety calculation. This involves defining and quantifying the geometric and dimensional representations of the repository for each scenario plus the physical, mathematical and numerical models that reflect its behaviour and the uncertainties associated with all the parameters required to quantify the impact. A summary will be given of these various aspects. The numerical simulations are then performed on the Alliances platform which integrates the various computer codes required for the physical representation of the system. (authors)
During the 1990's, natural gas was the energy source with the fastest rate of growth in the world energy balance. Nevertheless, recent evolutions of the energy context, in particular in terms of prices, have had a rather strong impact on the progress of the different energy sources penalizing gas a little. Beyond this competition between energies, which may increase, the medium-term perspectives of natural gas development is in keeping with an environment full of uncertainties. This article presents: the world supply and demand prospects for 2010-2015 (impact of high gas prices on other energy sources, occurrence of production constraints, political decisions of producing countries and world gas industry balance), trends on main markets (North America, Europe, Asia-Oceania), and international trade. (J.S.)
This report is a scoping study to examine research opportunities to improve the accuracy of the system dynamic load and generator models, data and performance assessment tools used by CAISO operations engineers and planning engineers, as well as those used by their counterparts at the California utilities, to establish safe operating margins. Model-based simulations are commonly used to assess the impact of credible contingencies in order to determine system operating limits (path ratings, etc.) to ensure compliance with NERC and WECC reliability requirements. Improved models and a better understanding of the impact of uncertainties in these models will increase the reliability of grid operations by allowing operators to more accurately study system voltage problems and the dynamic stability response of the system to disturbances.
Abstract The potential impact of climate change on areas of strategic importance for water resources remains a concern. Here, river flow projections for the River Medway, above Teston in southeast England are presented, which is just such an area of strategic importance. The river flow projections use climate inputs from the Hadley Centre Regional Climate Model (HadRM3) for the time period 1960 2080 (a subset of the early release UKCP09 projections). River flow predictions are calculated using CATCHMOD, the main river flow prediction tool of the Environment Agency (EA) of England and Wales. In order to use this tool in the best way for climate change predictions, model setup and performance are analysed using sensitivity and uncertainty analysis. The model's representation of hydrological ...
Environmental regulatory requirements at both the state and federal level are constantly changing, making it difficult for industry and R ampersand D program managers to project future compliance requirements and costs. Even if a company is trying to keep abreast of various proposed regulatory initiatives, the number of possible combinations of initiatives that could occur in the future seems virtually limitless. Uncertainty associated with potential future environmental compliance requirements makes the identification and evaluation of future investment and R ampersand D opportunities exceedingly difficult, and makes the process of systematic strategic planning increasingly complex. This paper describes a methodology for accounting for uncertain future environmental compliance costs in a systematic, comprehensive manner. Through analysis of proposed initiatives for making future environmental requirements more stringent, forecasting the likelihood of occurrence ...
An important aspect, which has to be considered in terms of municipal solid waste (MSW) management, is the stage of collection. The emissions generated from these systems can arrive to values that are of the same order of magnitude of emissions from combustion of waste in waste-to-energy plants. The present work faces the problem of transport, from intermediate station to the center of final combustion, placing attention to the emissions from scenarios that has been selected between real systems of management. This analysis can lead to highlight some important elements that can be useful to minimize the impacts.
The error estimation for calculated quantities relies on nuclear data uncertainty information available in the basic nuclear data libraries such as the U.S. Evaluated Nuclear Data File (ENDF/B). The uncertainty files (covariance matrices) in the ENDF/B library are generally obtained from analysis of experimental data. In the resonance region, the computer code SAMMY is used for analyses of experimental data and generation of resonance parameters. In addition to resonance parameters evaluation, SAMMY also generates resonance parameter covariance matrices (RPCM). SAMMY uses the generalized least-squares formalism (Bayes' method) together with the resonance formalism (R-matrix theory) for analysis of experimental data. Two approaches are available for creation of resonance-parameter covariance data. (1) During the data-evaluation process, SAMMY generates both a set of resonance parameters that fit the experimental data and the associated ...
Expressions for the spatial moments and macrodispersion tensor for sorbing solutes in heterogeneous formations were presented using a probabilistic model of a fluid residence time coupled with the particle position analysis. The fluid residence time was defined as a fraction of the actual time during which the particle stayed in the mobile fluid phase of the aquifer. The fluid residence time is a random variable whose variability comes as a result of the non-equilibrium sorption properties. The sorbing solute was assumed to be governed with first-order linear kinetics. The closed-form expressions were based on the stationarity in the kinetic process and on the first-order approximation in the hydraulic conductivity field and in the fluid residence time. The non-equilibrium effects were presented as a function of the spatial variability in hydraulic conductivity and temporal variability in the fluid residence time. The importance of the non-equilibrium processes in the field scale was ...
One of the main objectives of the Finnish Research Programme on Climate Change (SILMU) has been to assess the possible impacts of future changes in climate due to the enhanced greenhouse effect on natural systems and human activities in Finland. In order to address this objective, it was first necessary to specify the types of climate changes to be expected in the Finnish region. Estimates of future climate are conventionally obtained using numerical models, which simulate the evolution of the future climate in response to radiative forcing due to changes in the composition of the atmosphere (i.e. of greenhouse gases and aerosols). However, there are large uncertainties in the model estimates because current knowledge and understanding of atmospheric processes remains incomplete. Since accurate predictions of climate change are not available, an alternative approach is to develop scenarios. These are plausible projections which reflect the best ...
Waste form dissolution studies and preliminary performance analyses were carried out to contribute a part of the data needed for the selection of a waste form for the disposal of Savannah River Plant defense waste in a deep geologic repository. The first portion of this work provides descriptions of the chemical interactions between the waste form and the geologic environment. We reviewed critically the dissolution/leaching data for borosilicate glass and SYNROC. Both chemical kinetic and thermodynamic models were developed to describe the dissolution process of these candidate waste forms so as to establish a fundamental basis for interpretation of experimental data and to provide directions for future experiments. The complementary second portion of this work is an assessment of the impacts of alternate waste forms upon the consequences of disposal in various proposed geological media. Employing systems analysis methodology, we began to evaluate the performance ...
Postulated impacts of large energy releases were examined in the light of existing technical information. The magnitudes of direct atmospheric modifications were estimated, and the ecological and economic implications of the modifications were explored. Energy releases from energy centers (10 to 40 power plants at a single site) and individual power plant clusters (1 to 4 power plants) were considered. In the atmosphere the energy will exist initially as increased temperature (sensible heat), moisture (latent heat), and air motion (kinetic energy). Addition of energy could result in increased cloudiness and fog, and changed precipitation patterns. A framework for economic analysis of the impacts of the postulated atmospheric modifications was established on the basis of costs and benefits. Willingness-to-pay was selected as the appropriate measure for valuing each impact. The primary and secondary ...
Pre-waste-emplacement groundwater travel time is one indicator of the isolation capability of the geologic system surrounding a repository. Two distinct modeling approaches exist for prediction of groundwater flow paths and travel times from the repository location to the designated accessible environment boundary. These two approaches are: (1) the deterministic approach which calculates a single value prediction of groundwater travel time based on average values for input parameters and (2) the stochastic approach which yields a distribution of possible groundwater travel times as a function of the nature and magnitude of uncertainties in the model inputs. The purposes of this report are to (1) document the theoretical (i.e., mathematical) basis used to calculate groundwater pathlines and travel times in a basalt system, (2) outline limitations and ranges of applicability of the deterministic modeling approach, and (3) explain the motivation ...
The long-lived nuclides of the americium and curium elements are of interest for their use in certain safeguard applications and for nuclear reactor burnup studies in waste management. Recommended values are presented for /sup 241,242m,243/Am, and for /sup 242,243,244,245,246,247,248,250/Cm. These values result from a consistent evaluation of all these half-lives. These preliminary estimates were presented earlier. The uncertainties are provided at the 95% confidence limit for each of the recommended values. It will be noted that many of the recommended errors considerably exceed errors quoted by individual authors in their publication, by up to an order of magnitude, e.g. the total half-life of /sup 242,246,248/Cm and the spontaneous fission half-life of /sup 244/Cm. These preliminary estimates for the half-lives were given previously. Efforts continue to reevaluate the various experiments to better gauge the systematic errors involved and ...
The purpose of this project was to compile a bibliography of references containing environmental transuranic radionuclide data. The authors intent was to identify those parameters affecting transuranic radionuclide transport that may be generic and those that may be dependent on chemical form and/or environmental conditions. An understanding of the unique characteristics and similarities between source terms and environmental conditions relative to transuranic radionuclide transport and cycling will provide the ability to assess and predict the long term impact on man and the environment. An additional goal of the literature review, was to extract the ranges of environmental transuranic radionuclide data from the identified references for inclusion in a data base. Related to source term, these ranges of data can be used to calculate the dose to man from the radionuclides, and to perform uncertainty analyses on these dose assessments.
In the universe there are two different kinds of uncertain phenomena: stochastic and fuzzy or vague. Both uncertain phenomena have been found in structural problems. Therefore, rational decisions concerning the design of marine structures cannot be made without resorting to the methods which can take the uncertainties into account. The fundamental concept of structural fuzzy reliability problems and the methods to give the fuzzy solution are introduced in the paper. Based on the principle of fuzzy decision-making the method to obtain the crisp solution of structural fuzzy reliability analysis is proposed by means of the Bound Search method. Illustrative numerical examples, ship bottom plates under slamming impact pressures are solved. The influence of variation of allowable tolerances in the fuzzy reliability indexes is discussed.
A comprehensive assessment on the eligibility of reduced activation (RA) steels as structural chamber material in Inertial Fusion Energy thick-liquid concepts is performed. As far as alloying elements, it is shown that the activation of tungsten is a question to discuss. Regarding impurity elements, it is analyzed if they could question the possibility of obtaining real RA steels for shallow land burial (SLB). The effect of the thickness of the liquid wall on the SLB response of alloying and impurity elements is computed. It seems that a reasonable liquid thickness of about 80 cm is allowable to obtain SLB acceptability of real RA steels. And above all, we have estimated the impact of cross section uncertainties when addressing the former questions, and we identify those to be improved. The necessary improvement of some tungsten and niobium cross sections is justified. (authors)
The coupled neutron-gamma cross section libraries BUGLE-80 and SAILOR are compared, with focus on gamma production and transport and its sensitivity to the thermal component of the neutron flux. In addition, the importance of the prompt versus delayed components of the gamma source is addressed. Although BUGLE-80 shows some discrepancies in the core region, the two libraries demonstrate similar capability in the vicinity of the pressure vessel and beyond. The delayed fission product gammas from the core have little impact on the local gamma fluxes beyond the pressure vessel. Although thermal neutron capture is the dominant component of the gamma source, there is little sensitivity of the gamma source to uncertainties in the thermal neutron cross sections, due to compensating effects which tend to keep the thermal neutron capture rate relatively constant.
Experiences in hazardous materials transportation show that purely strategic or planning approaches have considerable shortcomings and that real-time management must be addressed. The commercialization of advanced location and communications technology provides the basis for real-time guidance. Considering the possibilities this new technology offers, a real-time routing model is proposed. It is based on the premises that a human dispatcher must assess the impacts of sudden events on safety and transportation costs and evaluate safe and cost-effective routing alternatives. Due to high uncertainty and time constraints in this real-time environment, risks and transportation costs are expressed as preferences on an ordinal scale. The model has been integrated into a decision support system and assessed in an experimental setting. This ordinal preference model turned out to be superior to a utility approach due to its robustness in risk assessment ...
Environmental Impact Assessment (EIA) must account for legally protected and endangered species. Uncertainties relating to the validity and sensitivity of EIA arise from predictions and valuation of effects on these species. This paper presents a validity and sensitivity analysis of a model (BIO-SAFE) for assessment of impacts of land use changes and physical reconstruction measures on legally protected and endangered river species. The assessment is based on links between species (higher plants, birds, mammals, reptiles and amphibians, butterflies and dragon- and damselflies) and ecotopes (landscape ecological units, e.g., river dune, soft wood alluvial forests), and on value assignment to protected and endangered species using different valuation criteria (i.e., EU Habitats and Birds directive, Conventions of Bern and Bonn and Red Lists). The validity of BIO-SAFE has been tested by comparing predicted effects of landscape ...
For the first time absolute total cross sections for electron-impact excitation of a multiply-charged ion have been measured using an electron-energy-loss technique. Measurements were made near threshold for the process e + Si"3"+(3s"2S_1_/_2) #-># e+Si"3"+(3p"2P_1_/_2_,_3_/_2)-8.88 eV. The 10"-"1"5 cm"2 measured cross section agrees with results of 7-state close coupling calculations to better than the #+-#20% (90% CL) total uncertainty of the measurements. Convoluting the theoretical curve with a Gaussian energy distribution indicates an energy width of 0.15 < or approx. #DELTA#E < or approx. 0.20 eV. (orig.).
The report examines the scientific progress which has been made over the past years on the climate change issue. It examines shifts in emphasis on climate change debates and the implications of scientific uncertainty for the policy maker. Information on the impact of climate on various sectors, such as agriculture and coastal zones is also provided, as well as a case study on the UK. Regional impacts of climate change and associated economic implications are considered. The report also documents some different considerations for a climate change policy in the context of the latest meeting of contracting parties to the Un Framework Convention on Climate Change, held in Kyoto in December 1997. The report is divided into five sections: Introduction; Scientific progress; Climate change policy - the dilemma with implementation; Summary and conclusions; Summary of Kyoto`s results. 146 refs., 4 figs., 14 tabs., 2 apps.
Summary Electronic textiles are a vanguard of an emerging generation of smart products. They consist of small electronic devices that are seamlessly embedded into clothing and technical textiles. E-textiles provide enhanced functions in a variety of unobtrusive and convenient ways. Like many high-tech products, e-textiles may evolve to become a mass market in the future. In this case, large amounts of difficult-to-recycle products will be discarded. That can result in new waste problems. This article examines the possible end-of-life implications of textile-integrated electronic waste. As a basis for assessment, the innovation trends of e-textiles are reviewed, and an overview of their material composition is provided. Next, scenarios are developed to estimate the magnitude of future e-tex...
Idiopathic pulmonary fibrosis is the most lethal form of diffuse lung fibrosis, killing approximately half of those affected within 2-3 years of diagnosis. Until recently, no therapies had been shown to have an impact on disease progression. The Clinical Studies Assessing Pirfenidone (Esbriet) in IPF: Research of Efficacy and Safety Outcomes (CAPACITY) program comprised two almost identical double-blind placebo-controlled studies assessing the effects of pirfenidone on change in forced vital capacity, the primary end point, over a 72-week period. One of these studies was positive, matching in magnitude the benefit seen in two previous positive Japanese studies. The other study did not meet its primary end point but positive trends were consistent in this and a number of secondary end point...
RODbaffle heat exchanger is a kind of shell-and-tube heat exchanger with eminent performance. Because of the characteristics of tube bundle support structure, fluid flow on shellside is longitudinal and periodical, and fluid flow is of symmetry in landscape orientation. According to the fluid flow characteristics on shellside and ignoring the impact of inlet, outlet and shell wall, a periodic flow unit duct was taken as the simplified model of the shellside to perform numerical simulation by using CFD code, FLUENT. It was found that the both errors in magnitude of the main fluid velocities and heat transfer coefficients between results of simulation and that of experiment or correlations are less than 10%, and the errors of pressure drop between simulation and correlation are no more than 20%. The detailed characteristics and relation of fluid flow and heat transfer on shellside of the RODbaffle heat exchanger were analyzed using the simulation ...
Neutrinos have recently been shown to have collective phenomenon which causes them to flavor transform near the center of the supernova. These flavor transformations can potentially impact supernova nucleosynthesis, particularly for processes that occur near the core, such as the r-process. In this paper we explore the effects of collective oscillations on a supernova r-process. We find that magnitude of the effect depends senstivitely on the astrophysical conditions?in particular on the interplay between the time when nuclei begin to exist in significant numbers and the time when the collective oscillation begins. Because of this delicate balance, a more definitive understanding of the astrophysical conditions is necesssary. Here, we explore scenarios based on outflow models currently in ...
The primary methodology that is used for disposal of municipal solid waste is the use of land fills; 80--85% of the municipal solid waste (MSW) produced in the country currently is land filled. The two other disposal alternatives used are recycling and incineration. Waste-to-energy technology (WTE) which incinerates MSW to produce electricity and/or steam is attractive in other cases since it reduces landfill volume, reduces the consumption of fossil and other fuels, and produces a revenue stream from the sale of the electricity or steam. The gaseous effluents from landfills can also be used to fuel power plants. Recycling and material separation programs can have a substantial impact on the throughput and heating value of MSW collected and thus impact WTE plant economics; the magnitude of the impact will depend upon a number of factors such as what materials and what fraction are separated and ...
In this research, first, event and process relevant to the key words (or scenario initiator) such as volcanism have been identified and, especially a middle-scale eruption scenario including pyroclastic flows has been analyzed as the catastrophic scenario, which inspires ordinary people to have tremendous concern. Secondly, based upon the characteristic events and processes of each scenario considered in the above and through the research of existing model of such risk, quantitative concept (release amount magnitude, release mode, release form, frequency of release, probability etc.) and impact on repository system, facility and environment have been analyzed, defended and defined. Model which can assess and analyze such impact has been built. Using these models, risks directly or indirectly caused by HLW repository have been calculated. Finally, the process for assessing the consequence of volcanism scenario and its risk ...
The work reported is to evaluate two alternative resource recovery systems which would produce a fuel or an energy product (steam) for sale to an industrial plant. The first alternative is a refuse derived fuel (RDF) production facility which would process waste to produce fuel for sale to the plant. The RDF would be co-fired with coal in new boilers. The second alternative is a mass burn steam generation facility which would produce high pressure superheated steam for sale. The steam would be used by the plant to cogenerate electricity and for the process. Conceptual designs are developed for each alternative to form the basis of estimates of capital and operating costs and potential energy revenues. Operating requirements are developed for both alternatives. An assessment is made of the impact of both alternatives on the environment, and it is concluded that the impact of either alternative will be negligible. Order of ...
The success in developing of the oil industry operating in offshore-onshore terminals, connected by pipelines with the facilities of the coastal zone, can be attributed partially to the beach morpho dynamic monitoring. This study represents a solution to the concerns of the technical operations in coastal zones because it minimizes the impact of the petroleum production and it assures the environmental protection associated to the risks of the pipelines breaking. This impact type results mainly of the vertical and horizontal displacements of the beach, from the coastal dunes to the shore face. The mobility of the profile is associated to the magnitude of the sedimentary processes, which reproduce naturally or not, in scale of time that can vary among few days, years or decades. For the monitoring and interpretation of the beach profile mobility the following methods are recommended: calculation of the closure depth with ...
This work investigates the impingement of a liquid microdroplet onto a glass substrate at different temperatures. A finite-element model is applied to simulate the transient fluid dynamics and heat transfer during the process. Results for impingement under both isothermal and non-isothermal conditions are presented for four liquids: isopropanol, water, dielectric fluid (FC-72) and eutectic tin-lead solder (63Sn-37Pb). The objective of the work is to select liquids for a combined numerical and experimental study involving a high resolution, laser-based interfacial temperature measurement to measure interfacial heat transfer during microdroplet deposition. Applications include spray cooling, micro-manufacturing and coating processes, and electronics packaging. The initial droplet diameter and impact velocity are 80 {\\mu}m and 5 m/s, respectively. For isothermal impact, our simulations with water and isopropanol show very good agreement with ...
BackgroundPolicies on waste disposal in Europe are heterogeneous and rapidly changing, with potential health implications that are largely unknown. We conducted a health impact assessment of landfilling and incineration in three European countries: Italy, Slovakia and England.MethodsA total of 49 (Italy), 2 (Slovakia), and 11 (England) incinerators were operating in 2001 while for landfills the figures were 619, 121 and 232, respectively. The study population consisted of residents living within 3 km of an incinerator and 2 km of a landfill. Excess risk estimates from epidemiological studies were used, combined with air pollution dispersion modelling for particulate matter (PM10) and nitrogen dioxide (NO2). For incinerators, we estimated attributable cancer incidence and years of life lost (YoLL), while for landfills we estimated attributable cases of congenital anomalies and low birth weight infants.ResultsAbout 1,000,000, 16,000, and 1,200,000 subjects lived ...
Waste management has gone through a history of shifting problems, demands, and strategies over the years. In contrast to the long prevailing view that the problem could be solved by hiding or moving it, waste is now viewed as a problem ranging from local to global concern, and as being an integral part of several sectors in society. Decisive for this view has been society's increasing complexity and thus the increasing complexity of waste, together with a general development of environmental consciousness, moving from local focus on point emission sources, to regional and global issues of more complex nature. This thesis is about the development and application ORWARE; a model for computer aided environmental systems analysis of municipal waste management. Its origin is the hypothesis that widened perspectives are needed in waste management decision-making to avoid severe sub-optimisation of environmental performance. With a strong foundation in life cycle assessment (LCA), ...
This report aims at presenting a view upon uncertainty analysis of phenomenological models with an emphasis on the identification and documentation of various types of uncertainties and assumptions in the modelling of the phenomena. In an uncertainty analysis, it is essential to include and document all unclear issues, in order to obtain a maximal coverage of unresolved issues. This holds independently on their nature or type of the issues. The classification of uncertainties is needed in the decomposition of the problem and it helps in the identification of means for uncertainty reduction. Further, an enhanced documentation serves to evaluate the applicability of the results to various risk-informed applications. (au)
A performance assessment of the operating Solid Waste Storage Area 6 (SWSA 6) facility for the disposal of low-level radioactive waste at the Oak Ridge National Laboratory has been prepared to provide the technical basis for demonstrating compliance with the performance objectives of DOE Order 5820.2A, Chapter 111.2 An analysis of the uncertainty incorporated into the assessment was performed which addressed the quantitative uncertainty in the data used by the models, the subjective uncertainty associated with the models used for assessing performance of the disposal facility and site, and the uncertainty in the models used for estimating dose and human exposure. The results of the uncertainty analysis were used to interpret results and to formulate conclusions about the performance assessment. This paper discusses the approach taken in analyzing the uncertainty ...
Sheltering, evacuation and distribution of stable iodine tablets are considered to be major early emergency actions aiming at diminishing the consequences after a release of radioactive materials from nuclear power plants into the air. Whether in real situations emergency managers will act accordingly is hard to predict. Uncertainties associated with these decisions are termed 'volitional' uncertainties. These uncertainties, however, cannot be assessed by expert judgements as they express the decision at stake in an emergency situation. Uncertainties on the times to implement countermeasures and on the times for the general population to respond to these measures can be assessed by experts, as they represent 'lack-of-knowledge' uncertainties. This paper describes the difference in approach of both types of uncertainties and ...
Leakage of CO{sub 2} and displaced brine from geologic carbon sequestration (GCS) sites into potable groundwater or to the near-surface environment is a primary concern for safety and effectiveness of GCS. The focus of this study is on the estimation of the probability of CO{sub 2} leakage along conduits such as faults and fractures. This probability is controlled by (1) the probability that the CO{sub 2} plume encounters a conductive fault that could serve as a conduit for CO{sub 2} to leak through the sealing formation, and (2) the probability that the conductive fault(s) intersected by the CO{sub 2} plume are connected to other conductive faults in such a way that a connected flow path is formed to allow CO{sub 2} to leak to environmental resources that may be impacted by leakage. This work is designed to fit into the certification framework for geological CO{sub 2} storage, which represents vulnerable resources such as potable groundwater, health and safety, ...
Significant development of an oil shale industry has been projected over the next few decades. The nation's largest oil shale reserves exist in the Wyoming Basin and Colorado Plateau physiographic provinces. This study presents a brief description of the environmental setting and land-use pattern of the region, with a review of the major environmental issues associated with each proposed technology for extracting shale oil. Serious effects may be expected from the modification of very large land surfaces through open-pit mining and spent-shale disposal. The impacts include habitat destruction, potential species loss, and deterioration of surface and groundwater quality. In situ retorting of shale may result in major alterations of groundwater quantity, quality, and flow regimes. Mine dewatering from in situ retorting requires the disposal of large volumes of highly saline water, threatening the quality of subsurface and surface water resources. A ...
In May 2002, the United States Department of Energy (DOE) signed Assistance Instrument Number DE-FC09-02CH11109 with the Medical University of South Carolina (MUSC) to support the Environmental Biosciences Program (EBP). This funding instrument replaces DOE Assistance Instrument Number DE-FC02-98CH10902. EBP is an integrated, multidisciplinary scientific research program, employing a range of research initiatives to identify, study and resolve environmental health risks. These initiatives are consistent with the MUSC role as a comprehensive state-supported health sciences institution and with the nation's need for new and better approaches to the solution of a complex and expansive array of environment-related health problems. The intrinsic capabilities of a comprehensive health sciences institution enable MUSC to be a national resource for the scientific investigation of environmental health issues. EBPs success as a nationally prominent research program is due, in part, to ...
In May 2002, the United States Department of Energy (DOE) signed Assistance Instrument Number DE-FC09-02CH11109 with the Medical University of South Carolina (MUSC) to support the Environmental Biosciences Program (EBP). This funding instrument replaces DOE Assistance Instrument Number DE-FC02-98CH10902. EBP is an integrated, multidisciplinary scientific research program, employing a range of research initiatives to identify, study and resolve environmental health risks. These initiatives are consistent with the MUSC role as a comprehensive state-supported health sciences institution and with the nation's need for new and better approaches to the solution of a complex and expansive array of environment-related health problems. The intrinsic capabilities of a comprehensive health sciences institution enable MUSC to be a national resource for the scientific investigation of environmental health issues. EBPs success as a nationally prominent research program is due, in part, to ...
In May 2002, the United States Department of Energy (DOE) signed Assistance Instrument Number DE-FC09-02CH11109 with the Medical University of South Carolina (MUSC) to support the Environmental Biosciences Program (EBP). This funding instrument replaces DOE Assistance Instrument Number DE-FC02-98CH10902. EBP is an integrated, multidisciplinary scientific research program, employing a range of research initiatives to identify, study and resolve environmental health risks. These initiatives are consistent with the MUSC role as a comprehensive state-supported health sciences institution and with the nation's need for new and better approaches to the solution of a complex and expansive array of environment-related health problems. The intrinsic capabilities of a comprehensive health sciences institution enable MUSC to be a national resource for the scientific investigation of environmental health issues. EBPs success as a nationally prominent research program is due, in part, to ...
In May 2002, the United States Department of Energy (DOE) signed Assistance Instrument Number DE-FC09-02CH11109 with the Medical University of South Carolina (MUSC) to support the Environmental Biosciences Program (EBP). This funding instrument replaces DOE Assistance Instrument Number DE-FC02-98CH10902. EBP is an integrated, multidisciplinary scientific research program, employing a range of research initiatives to identify, study and resolve environmental health risks. These initiatives are consistent with the MUSC role as a comprehensive state-supported health sciences institution and with the nation's need for new and better approaches to the solution of a complex and expansive array of environment-related health problems. The intrinsic capabilities of a comprehensive health sciences institution enable MUSC to be a national resource for the scientific investigation of environmental health issues. EBPs success as a nationally prominent research program is due, in part, to ...
In May 2002, the United States Department of Energy (DOE) signed Assistance Instrument Number DE-FC09-02CH11109 with the Medical University of South Carolina (MUSC) to support the Environmental Biosciences Program (EBP). This funding instrument replaces DOE Assistance Instrument Number DE-FC02-98CH10902. EBP is an integrated, multidisciplinary scientific research program, employing a range of research initiatives to identify, study and resolve environmental health risks. These initiatives are consistent with the MUSC role as a comprehensive state-supported health sciences institution and with the nation's need for new and better approaches to the solution of a complex and expansive array of environment-related health problems. The intrinsic capabilities of a comprehensive health sciences institution enable MUSC to be a national resource for the scientific investigation of environmental health issues. EBPs success as a nationally prominent research program is due, in part, to ...
There is an increasing interest in using novel methods to generate electrical energy using wind and solar energy sources. Unfortunately, such energy sources are intermittent, and, therefore, conventional sources must still be available to meet demand during critical periods. In addition, renewable energy technologies are still expensive in general, although extensive research programs are being conducted to overcome this disadvantage. Hence, reliability, economic assessment and environmental impacts are three objectives to be satisfied simultaneously when designing either an autonomous or a grid-connected hybrid power generation system. The installation of any of these two systems should, undoubtedly, be preceded by an assessment of the available resources at the candidate site. In addition, many other factors are to be studied, including economics of transmission lines, site constraints, distances etc. In this thesis, the subjective judgments of various experts, ...
Consideration of the technical feasibility of Yucca Mountain in Nevada as the site for a high-level nuclear waste repository has led to an intense debate regarding the economic, social, and political impacts of the repository. Impediments to the siting process mean that the nuclear waste problem is being resolved by adhering to the status quo, in which nuclear waste is stored at scattered sites near major population centers. To assess the merits of alternative siting strategies--including both the permanent repository and the status quo- we consider the variables that would be included in a model designed to select (1) the optimal number of disposal facilities, (2) the types of facilities (e.g., permanent repository or monitored retrievable facility), and (3) the geographic location of storage sites. The objective function in the model is an all-inclusive measure of social cost. The intent of the exercise is not to demonstrate the superiority of any single disposal ...
SYVAC3 (Systems Variability Analysis Code, generation 3) is a computer program that implements a method called systems variability analysis to analyze the behaviour of a system in the presence of uncertainty. This method is based on simulating the system many times to determine the variation in behaviour it can exhibit. SYVAC3 specializes in systems representing the transport of contaminants, and has several features to simplify the modelling of such systems. It provides a general tool for estimating environmental impacts from the dispersal of contaminants. This report describes the use and structure of SYVAC3. It is intended for modellers, programmers, operators and reviewers who deal with simulation codes based on SYVAC3. From this manual they can learn how to link a model with SYVAC3, how to set up an input file, and how to extract results from output files. The manual lists the subroutines of SYVAC3 that are available for use by models, and ...
Full text.Increased environmental concerns and the emphasis on material and energy recovery are gradually changing the orientation of municipal solid waste (MSW) management and planning. In this context, the application of optimization techniques have been introduced to design the least cost solid waste management systems, considering the variety of management processes (recycling, composting, anaerobic digestion, incineration and land filling) and the existence of uncertainties associated with the number of system components and their interrelations. This study presents a model that was developed and applied to serve as a solid socio-economic and environmental considerations. The model accounts for solid waste generation rates, composition, collection, treatment, disposal as well as potential environmental impacts of various MSW management techniques. The model follows a linear programming formulation with the framework of dynamic ...
A case-control study on lung cancer and radon exposure in dwellings has been carried out in Lazio, a high indoor radon region of Central Italy. A total of about 400 cases and 400 controls were recruited and radon concentration was measured in a total of about 1850 dwellings. In each dwelling, radon concentration measurement devices were placed in both the main bedroom and living room for two consecutive six-month periods. Each radon device, enclosed in a sealed polyethylene bag, contains two LR 115 detectors, each being covered by a thin absorber to reduce the alpha-energy within the detector sensitive range. A quality assurance program, described in this paper, was applied in order to reduce radon concentration measurement uncertainty, which have a significant impact on the results of an epidemiological study. The reported internal quality control and intercomparison results are compared with the results of other studies, and show that the ...
This report examines the use of probabilistic methods in dealing with the problem of potential earthquake-induced liquefaction of foundation soils at an example dam site located in the central United States, near the New Madrid earthquake zone. The example dam is assumed to be a 1-mile long rolled-filled embankment founded on a 100-ft deep deposit of interbedded alluvial gravels, sands, silts, and clays. The study is seen as an opportunity to examine probabilistic concepts and procedures in the framework of an example engineering project. In this context, the main practical value of a probabilistic approach is that it permits more informed decision making about further data acquisition, additional engineering analysis, and if necessary, remedial action. The specific aim of the study is to show how probabilistic procedures complement and help to reinterpret the results of deterministic (earthquake-induced) liquefaction analysis. The procedures focus on evaluating the ...
We present a fully relativistic formalism for describing neutrino-induced $\\Delta$-mediated single-pion production from nuclei. We assess the ambiguities stemming from the $\\Delta$ interactions. Variations in the cross sections of over 10% are observed, depending on whether or not magnetic-dipole dominance is assumed to extract the vector form factors. These uncertainties have a direct impact on the accuracy with which the axial-vector form factors can be extracted. Different predictions for $C_5^A(Q^2)$ induce up to 40-50% effects on the $\\Delta$-production cross sections. To describe the nucleus, we turn to a relativistic plane-wave impulse approximation (RPWIA) using realistic bound-state wave functions derived in the Hartree approximation to the $\\sigma$-$\\omega$ Walecka model. For neutrino energies larger than 1 GeV, we show that a relativistic Fermi-gas model with appropriate binding-energy correction produces comparable results as ...
The performance and lifetime of energy storage in batteries are an important part of many renewable based energy systems. Not only do batteries impact on the system performance but they are also a significant expenditure when considering the whole life cycle costs. Poor prediction of lifetime can, therefore, lead to uncertainty in the viability of the system in the long term. This report details the work undertaken to investigate and develop two different battery life prediction methodologies with specific reference to their use in hybrid renewable energy systems. Alongside this, results from battery tests designed to exercise batteries in similar modes to those that they experience in hybrid systems have also been analysed. These have yielded battery specific parameters for use in the prediction software and the first results in the validation process of the software are also given. This work has been part of the European Union Benchmarking ...
This study examines the sensitivity of the travel time distribution predicted by a reference case model to (1) scale of representation of the model parameters, (2) size of the model domain, (3) correlation range of log-transmissivity, and (4) cross correlations between transmissivity and effective thickness. The basis for the reference model is the preliminary stochastic travel time model previously documented by the Basalt Waste Isolation Project. Results of this study show the following. The variability of the predicted travel times can be adequately represented when the ratio between the size of the zones used to represent the model parameters and the log-transmissivity correlation range is less than about one-fifth. The size of the model domain and the types of boundary conditions can have a strong impact on the distribution of travel times. Longer log-transmissivity correlation ranges cause larger variability in the predicted travel times. Positive cross ...
One of the issues identified in the US Nuclear Regulatory Commission`s Nuclear Plant Aging Research program plan is the need to understand the state of ``mothballed`` or other out-of-service equipment to ensure subsequent safe operation. Programs for proper storage and preservation of materials and components are required by NRC regulations (10 CFR 50, Appendix B). However, materials and components have been seriously degraded due to improper storage, protection, or layup, at facilities under construction as well as those with operating licenses. Pacific Northwest Laboratory has evaluated management of aging for unstarted or mothballed nuclear power plants. The investigations revealed that no uniform guidance in the industry addresses reactor layup. In each case investigated, layup was not initiated in a timely manner, primarily because of schedule uncertainty. Hence, it is reasonable to assume that this delay resulted in accelerated aging of some ...
The management programs for invasive species have been proposed and implemented in many regions of the world. However, practitioners and scientists have not reached a consensus on how to control them yet. One reason is the presence of various uncertainties associated with the management. To give some guidance on this issue, we characterize the optimal strategy by developing a dynamic model of invasive species management under uncertainties. In particular, focusing on (i) growth uncertainty and (ii) measurement uncertainty, we identify how these uncertainties affect optimal strategies and value functions. Our results suggest that a rise in growth uncertainty causes the optimal strategy to involve more restrained removals and the corresponding value function to shift up. Furthermore, we also...
The global effect of activation cross-section uncertainties on calculated radiological quantities is investigated for the first time using a methodology based on Monte Carlo random sampling. The method is applied to the calculation of the uncertainty in the contact dose rate from the gunite shielding of the National Ignition Facility chamber after 30 yr of pulsed irradiation. Some critical cross section contributing significantly to the overall uncertainty are identified. By a reasonable reduction of the uncertainty in those cross sections, the accuracy in the calculated total contact dose rate is greatly improved.
I present a promising route to harmonize distance measurements based on clump giants and RR Lyrae stars. This is achieved by comparing the brightness of these distance indicators in three environments: the solar neighborhood, Galactic bulge and Large Magellanic Cloud (LMC). As a result of harmonizing the distance scales in the solar neighborhood and Baade's Window, I derive the new absolute magnitude of RR Lyrae stars, M{sub v}(RR) at [Fe/H] = -1.6 (0.59 {+-} 0.05, 0.70 {+-} 0.05). Being somewhat brighter than the statistical parallax solution, but fainter than typical results of the main sequence fitting to Hipparcos data, these values of M{sub V}(RR) favor intermediate or old ages of globular clusters. Harmonizing the distance scales in the LMC and Baade's Window, I show that the most likely distance modulus to the LMC, {mu}{sub LMC} is in the range 18.24 - 18.44. The Hubble constant of about 70 km/s/Mpc reported by the HST Key Project is based ...
Motivated by the strong discrepancy between the main-sequence turnoff age and the white dwarf cooling age in the metal-rich open cluster NGC 6791, we compute a grid of white dwarf evolutionary sequences that incorporates for the first time the energy released by the processes of "2"2Ne sedimentation and of carbon/oxygen phase separation upon crystallization. The grid covers the mass range from 0.52 to 1.0 M _s_u_n, and is appropriate for the study of white dwarfs in metal-rich clusters. The evolutionary calculations are based on a detailed and self-consistent treatment of the energy released from these two processes, as well as on the employment of realistic carbon/oxygen profiles, of relevance for an accurate evaluation of the energy released by carbon/oxygen phase separation. We find that "2"2Ne sedimentation strongly delays the cooling rate of white dwarfs stemming from progenitors with high metallicities at moderate luminosities, while carbon/oxygen phase separation adds ...
The effect of aerosol on clouds poses one of the largest uncertainties in estimating the anthropogenic contribution to climate change. Small human-induced perturbations to cloud characteristics via aerosol pathways can create a change in the top-of-atmosphere radiative forcing of hundreds of Wm-2. Here we focus on links between aerosol and deep convective clouds of the Atlantic and Pacific Intertropical Convergence Zones, noting that the aerosol environment in each region is entirely different. The tops of these vertically developed clouds consisting of mostly ice can reach high levels of the atmosphere, overshooting the lower stratosphere and reaching altitudes greater than 16 km. We show a link between aerosol, clouds and the free atmosphere wind profile that can change the magnitude and sign of the overall climate radiative forcing. We find that increased aerosol loading is associated with taller cloud towers and anvils. The taller clouds ...
As the 20th century draws to a close, both individual countries and the world community face challenging problems related to the supply and use energy. These include local and regional environmental impacts, the prospect of global climate and sea level change associated with the greenhouse effect, and threats to international relations in connection with oil supply or nuclear proliferation. For developing countries, the financial cost of providing energy to provide basic needs and fuel economic development pose an additional burden. To assess the magnitude of future problems and the potential effectiveness of response strategies, it is important to understand how and why energy use has changed in the post and where it is heading. This requires study of the activities for which energy is used, and of how people and technology interact to provide the energy services that are desired. The authors and their colleagues have analyzed trends in energy ...
As the 20th century draws to a close, both individual countries and the world community face challenging problems related to the supply and use energy. These include local and regional environmental impacts, the prospect of global climate and sea level change associated with the greenhouse effect, and threats to international relations in connection with oil supply or nuclear proliferation. For developing countries, the financial cost of providing energy to provide basic needs and fuel economic development pose an additional burden. To assess the magnitude of future problems and the potential effectiveness of response strategies, it is important to understand how and why energy use has changed in the post and where it is heading. This requires study of the activities for which energy is used, and of how people and technology interact to provide the energy services that are desired. The authors and their colleagues have analyzed trends in energy ...
In this research, new thin freestanding films of poly(methyl methacrylate) (PMMA)/50% epoxidised natural rubber (ENR 50) were doped with lithium triflate, LiCF3SO3 salt was prepared by a solvent casting method. The incorporation of ENR 50 is found to increase the conductivity of PMMA/LiCF3SO3 by two orders of magnitude at room temperature. The highest conductivity achieved was 5.09x10-5Scm-1 at room temperature when 60% of LiCF3SO3 salt was introduced into the PMMA blend containing 10% ENR 50. The formation of excessive hydrogen bonds and interchain crosslinking limit the performance of the blend at higher concentrations of ENR 50. The ionic conduction mechanisms in PMMA/ENR 50/LiCF3SO3 electrolytes obey the Arrhenius rule in which the ion transport in these materials is thermally assisted...
One of the least understood regions of the upper atmosphere is the thermosphere, principally due to the difficulty of making observations. The neutral atmosphere is known to be highly variable, and its composition and density varies by several orders of magnitude due to solar activity, diurnal cycles, latitude, geomagnetic activity, and gravity waves. In the past, most in-situ measurements of the neutral atmosphere have utilized detectors that are dependent on arrival angle and energy accommodation of incoming species, so that information related to nascent velocity distribution and reactive species abundances is often masked. This paper will review design concepts and laboratory tests related to the development of a novel open-ionizer, neutral particle detector for space environment measurements which can overcome these limitations. The sensor features a very large field-of-view suitable for sounding rocket missions. This time-of-flight instrument uses ...
This paper summarizes substance flow analyses for four organic substances in the City of Stockholm, Sweden: diethylhexyl phthalate (DEHP), alkylphenolethoxylates (APEO), polybrominated diphenylethers (PBDE) and chlorinated paraffins (CP). The results indicate that the stocks of APEO, PBDE and CP all are approximately 200-250 tonnes, whereas the DEHP stock is two orders of magnitude larger. Emissions can be linked to imported consumer goods such as electronics (PBDE) and textiles (APEO), and to construction materials (DEHP, CP). For several of the substances considerable amounts remain in the technosphere for a long time, even after use of the substance in new products has been eliminated. For example, the use of DEHP as plasticizer for PVC plastics in cables and floorings has more or less been phased-out, but still these applications make up a stock of some 20,000 tonnes (85% of the total DEHP stock in Stockholm) and emit 28 tonnes of DEHP annually (93% of overall ...
The objective of this study is to develop a method to aid in the selection of an overburden handling system in surface coal mining. The selection procedure consists of three major parts. The first part is aimed at rating the equipment's potential to perform the environmental protection related activities and then integrating this rating into the system selection process. The second part is an engineering analysis of the design of pit layouts and the operation of alternative overburden handling systems. The third part consists of a cost and sensitivity analysis of alternative systems on different mining situations. Specifically, the work includes: (1) a Delphi study to determine the magnitude of the environmental impacts and to quantify the relationship between mining practices and environmental remedies, (2) a scoring model to set up an index of the relative capability of equipment to do the environmental protection related jobs, (3) ...
Full text.Surficial sediment samples were collected from seventeen springs distributed all over Lebanon (east, west, north and south). Concentrations of metals Ca, Fe, Mn, Ni, Cu, Cr, Zn and Pb were determined by energy dispersive x-ray fluorescence technique. Irradiation was done by the radioisotope source Cd-109 and the detection by an EG and G Si(Li) detector. These analysis was done in attempt to assess the impact of anthropogenic sources on ground water quality. Metals concentration in sediment were found to be (Ca:0.05-47%, Fe:0.24-4.2%, Cr:magnitude as those obtained from other regions of ...
With the advent of the Information Superhighway, many organizations have been spurred into re-examining current spacecraft architectures to determine how the significantly higher communications capacities of the future will be accommodated. Opinion is divided on many issues in this arena, and none more so than the discussion that revolves around whether several large satellites in Geosynchronous Orbit (GEO) offer a better all-round service to the user community than a fleet of small satellites in Low Earth Orbit (LEO). Although this paper does not attempt to debate this particular issue, a clear finding of the work carried out by the author and others, was that considerable growth potential exists by simply increasing the physical size and capacity of conventional geosynchronous satellites while causing a minimal impact on existing ground systems and infrastructures. The work described here forms part of a power systems study carried out by Lockheed Martin Astro ...
We have constructed a specific supersymmetric flipped SU(5) GUT model in which bilarge neutrino mixing is incorporated. Because the up-type and down-type quarks in the model are flipped in the representations ten and five with respect to the usual SU(5), the radiatively generated flavor mixing in squark mass matrices due to the large neutrino mixing has a pattern different from those in the conventional SU(5) and SO(10) supersymmetric GUTs. This leads to phenomenological consequences quite different from SU(5) or SO(10) supersymmetric GUT models. That is, it has almost no impact on B physics. On the contrary, the model has effects in top and charm physics as well as lepton physics. In particular, it gives promising prediction on the mass difference, #DELTA#M_D, of the D-D-bar mixing which for some ranges of the parameter space with large tan#beta# can be at the order of 10"9 #Planck constant# s"-"1, one order of magnitude smaller than the ...
To address the potential threat that suspect/counterfeit parts could pose to DOE workers and the public, the Office of the Deputy Assistant Secretary for Oversight initiated a number of activities beginning in mid-1995. Oversight placed increased emphasis on the field`s quality assurance-suspect/counterfeit parts programs during safety management evaluations, in keeping with the Office of Environment, Safety and Health (EH) oversight responsibilities, which include oversight of the Department`s quality assurance (QA) programs. In addition, Oversight reviewed relevant policy documents and occurrence reports to determine the nature and magnitude of the problem within the Department. The results of that review, contained in an Office of Oversight report, Independent Oversight Analysis of Suspect/Counterfeit Parts Within the Department of Energy (November 1995), indicate a lack of consistency and comprehensiveness in the Department`s QA-suspect/counterfeit parts ...
An uncertainty decrease is an very important issue for enhancing risk-informed (RI) activities worldwide. Especially, a relatively large uncertainty in a level-2 (L2) PSA risk compared with level-1 internal PSA risk has been a bottleneck problem in the RI application to the extent of a severe accident management. According to the ASME PRA standard in which sources of an uncertainty to capture a category-II RI (= Option 2) capability are listed, an uncertainty analysis which identifies the key sources of an uncertainty and includes sensitivity studies for dominant contributors to LERF (Large Early Release Frequency) needs to be provided. To solve these problems, USNRC have developed the 'SPAR-LERF' model related to the L2 RI application and 'L2 uncertainty assessment and improvement' work is being taken as a main PSA2 topic of the SARNET (Severe Accident Research ...
Atomic Energy of Canada has recently submitted for regulatory and public review an Environmental Impact Statement (EIS) on a concept for disposal of Canada`s nuclear fuel waste. The EIS is supported by nine primary references that summarize major aspects of the concept, including a postclosure environmental and safety assessment. The scope of the postclosure assessment is largely determined by the requirements of the Atomic Energy Control Board (AECB) of Canada. These requirements include a quantitative estimate of the annual effective dose equivalent to an individual in the most exposed group of people (the critical group) for 10,000 years following closure of the disposal facility, and a radiological risk criterion with an associated dose rate limit of 0.05 mSv/a. Over this long time frame, a quantitative assessment cannot be based on actual observations, and thus we use scientific arguments and simulations with mathematical models to infer long-term behavior and ...
The general objective of this workshop is to investigate and discuss methods by which uncertainties in mass balance models for toxics in the Great Lakes may be reduced. As described by the workshop prospectus, this paper is focused on problems of reducing (and quantifying) uncertainty as they relate to in situ field observations/system response measurements for the establishment of initial conditions, boundary conditions, calibration/confirmation data sets, and model post-audit data sets.'' I have taken this description to refer not only to the evaluation of uncertainty in the field observations themselves, but also to the uncertainty associated the analyses of in situ observations as they interact in the overall modeling process. Thus, I will be concerned here with quantification and reduction of uncertainty both (1) as they may be applied to descriptions of the ...
This paper deals with the experimental identification and the validation of a non-parametric probabilistic approach allowing model uncertainties and data uncertainties to be taken into account in the numerical model developed to predict low- and medium-frequency dynamics of structures. The analysis is performed for a composite sandwich panel representing a complex dynamical system which is sufficiently simple to be completely described and which exhibits, not only data uncertainties, but above all model uncertainties. The dynamical identification is experimentally performed for eight panels. The experimental frequency response functions are used to identify the non-parametric probabilistic approach of model uncertainties. The prediction of the low- and medium-frequency dynamical responses obtained with the stochastic system is compared with the experimental measurements.
As wastewater travels through a sewer system it undergoes changes in composition. The changes in composition may be caused by chemical, physical and/or biological processes. At present engineers do not take into consideration the impacts of these processes on the wastewater quality when designing wastewater treatment systems. However, the impact of these processes on the chemical oxygen demand, biochemical oxygen demand, nitrogen and phosphorus content of the wastewater can be significant. In the case of the biological processes, microorganisms present in the water as it travels through the sewer system are similar to those found in an activated sludge process. Given that the microorganism population and the hydraulic retention time often resembles that of an activated sludge process, it would seem only reasonable to look further into the possibility of using sewers as wastewater treatment systems. Furthermore, the plug flow regime of a ...
Coilguns have demonstrated their capability to launch projectiles to 1 km/s, and there is interest in their application for long-range precision strike weapons. However, the incorporation of cooling systems for repetitive operation will impact the mechanical design and response of the future coils. To assess the impact of such changes, an evaluation of the ruggedness and reliability of the existing 50 mm bore coil designed in 1993 was made by repeatedly testing at stress levels associated with operation in a coilgun. A two-coil testbed has been built with a static projectile where each coil is energized by its own capacitor bank. Simulation models of the applied forces generated in this testbed have been created with the SLINGSHOT circuit code to obtain loads equivalent to the worst-case anticipated in a 50 mm coilgun that could launch a 236 g projectile to 2 km/s. Bench measurements of the seven remaining coils built in 1993 have been used to ...
An ignition timing control apparatus is described for an internal combustion engine having a reference ignition timing comprising: sensing means for sensing vibrations including knocks of the engine; knock signal deriving means for deriving knock signals from the output of the sensing means; correction magnitude determining means for determining from the knock signals derived by the knock signal deriving means of ignition timing correction magnitude for suppressing the occurrence of knock; displacement magnitude determining means for determining from at least one of an output of the knock signal deriving means and an output of the correction magnitude determining means as a displacement magnitude for the reference ignition timing corresponding to the octane rating of a fuel used in the engine; and ignition timing determining means for setting the reference ignition timing at an ...
A computational procedure is proposed to perform uncertainty analysis for the calculation of the isotopic inventory and radiological quantities obtained as a linear function of it, due to uncertainties in the activation cross sections. The method is applied to determine the uncertainty of the calculated shallow burial index (SBI) from activated type 304 stainless steel (SS) in the most neutron-exposed zone of the HYLIFE-II vessel structure. Results are obtained by means of an element-by-element study. Some other types of steel are also investigated for comparison purposes. The SS304 is confirmed to be the most promising steel option. 16 refs., 2 tabs.
One of the key issues in safety assessment of high-level nuclear waste disposal is evaluating the effects of uncertainty inherent in radionuclide migration parameter values. In this paper, radionuclide transport parameter values and error variances (uncertainties) from in-situ tracer experiments, carried out in a single fracture at the Aespoe Hard Rock Laboratory (HRL) in Sweden, are identified by solving the inverse problem in a framework of the maximum likelihood theory. From the results, it is found that the parameter value uncertainty caused by a conceptual model of radionuclide migration is greater than that caused by a fluctuation in the observed breakthrough curve data. (author)
In application, there is also a little filtering of the tie points with RANSAC .... Sets the multiplier that is used to adjust the sigma (or uncertainty) of ...
Thermal expansions of a simulated fuel (SS-1) were measured by using a Dilatometer (DIL402C) from room temperature to 1900 K. The main procedure of an uncertainty evaluation followed the strategy of the UO{sub 2} fuel. Referring to the ISO (International Organization for Standardization) guide, the uncertainties of the thermal expansion were quantified in three parts - the initial length, the length variation, and the system calibration factor. The uncertainty of the thermal expansion for a simulated fuel was also compared with those of UO{sub 2} fuel.
12], the Predictive Capability Maturity Model (PCMM) [ref. 13], the Uncertainty Structure scale [ref. 11], and the Simulation Readiness Level (SRL) scale ...
The study described in this report is part of a project sponsored by the Toronto Atmospheric Fund, performed at the Lawrence Berkeley National Laboratory, to assess the potential role of surface property modifications on energy, meteorology, and air quality in the Greater Toronto Area (GTA), Canada. Numerical models were used to establish the possible meteorological and ozone air-quality impacts of increased urban albedo and vegetative fraction, i.e., ''cool-city'' strategies that can mitigate the urban heat island (UHI), significantly reduce urban energy consumption, and improve thermal comfort, particularly during periods of hot weather in summer. Mitigation is even more important during critical heat wave periods with possible increased heat-related hospitalization and mortality. The evidence suggests that on an annual basis cool-city strategies are beneficial, and the implementation of such measures is currently being ...
A first, partial, assessment is included of the low- to medium-temperature geothermal reserves in 20 Mexican States and their aggregate value. The assessment covers about 29.16% of the identified geothermal-surface manifestations in the public database. For reserve assessments, we use the volumetric method, supplemented with Montecarlo simulations and statistics, to quantify inherent uncertainties. Our estimations are presented on a state-by-state basis. We estimate the aggregated reserves of the 20 states as between 7.7 x 1016 and 8.6 x 1016 kJ, with 90% confidence. The most likely reservoir temperatures range between 60-180 degrees Celsius, with a mean of 111 degrees Celsius. Such massive amounts of recoverable energy-and the associated temperatures-are potentially important for the economic development of nearby localities and the nation. [Spanish] En este trabajo se hace una primera estimacion, parcial, de las reservas geotermicas de temperatura intermedia a ...
Until now policy makers and researchers considered the problem of uncertainty and verification to be of minor importance for the Kyoto process. However, the first studies that recently appeared on uncertainty estimation of carbon accounting reveal that uncertainties of the reported emissions on the country level are large. In an environment of such large uncertainties, verification of emission reductions must be viewed as a crucial mechanism to secure the very functioning of the Protocol. The paper provides a set of tools to strategically deal with the problem of uncertainty and verification under the Kyoto Protocol. This is done by: providing an overview of the instruments to deal with verification (no-, trend-, level- and top-down/bottom-up verification under PCA and FCA); compute costs scenarios for those instruments under various flexibility scenarios; and providing a short ...
A methodology and hypothetical case study are presented for incorporation of uncertainty and variability into calculations of human health risk appropriate for regional, or basin-scale, groundwater management problems. Uncertainty in well water concentration is introduced through complex contaminant migration patterns in the subsurface. Variability is considered in parameters related to individual behavior patterns and biological effects and to groundwater extraction and distribution networks. A joint uncertainty and variability (JUV) analysis is used to generate a two-dimensional distribution or risk surface that spans both transport uncertainty as well as individual variability. Cuts in this distributional surface (fractiles of variability and percentiles of uncertainty) are presented and discussed. Comparisons with alternative approaches based upon deterministic transport models ...
The Kyoto Protocol is often described as a good first step towards reducing greenhouse gas (GHG) emissions into the atmosphere. The Protocol endorses emissions trading, joint implementation including 'bubbling' between Annex 1 Parties, and a clean development mechanism that allows Annex 1 and non-Annex 1 Parties to act together to reduce emissions. However, the anticipated permit market will not function if uncertainties are not rigorously assessed and considered in any compliance process. With no reliable verification tool, it is impossible to effectively assess the different mechanisms and activities mentioned under the Protocol. Thus, it is very important to study the uncertainties underlying the Kyoto relevant GHGs, here with reference to Poland, because without the consideration of uncertainty robust verification can not occur. This paper presents information about the data used in the calculations as ...
Power system operating conditions vary with system configurations and loading conditions. Coefficients in nominal system model change in a complex manner with different operating point and so does system dynamic behavior. With the aid of unstructured and structured uncertainty descriptions, the worst system variations can be estimated and formulated into two different uncertainty models in frequency domain; multiplicative unstructured uncertainty in the form of transfer function and structured uncertainty with the parametric uncertainty description. The uncertainty descriptions are then incorporated into system nominal model to perform H{sub {infinity}} and {mu} based robust power system stabilizer (PSS) design. Both approaches to the PSS design enable the power system to remain stable over a wide range of system operating conditions but the different ...
This paper presents a new technique--Integrated Bayesian Uncertainty Estimator (IBUNE) to account for the major uncertainties of hydrologic rainfall-runoff predictions explicitly. The uncertainties from the input (forcing) data--mainly the precipitation observations and from the model parameters are reduced through a Monte Carlo Markov Chain (MCMC) scheme named Shuffled Complex Evolution Metropolis (SCEM) algorithm which has been extended to include a precipitation error model. Afterwards, the Bayesian Model Averaging (BMA) scheme is employed to further improve the prediction skill and uncertainty estimation using multiple model output. A series of case studies using three rainfall-runoff models to predict the streamflow in the Leaf River basin, Mississippi are used to examine the necessity and usefulness of this technique. The results suggests that ignoring either input forcings error or model ...
This article introduces a predictive capability for Hg retention in any Ca-based wet flue gas desulfurization (FGD) scrubber, given mercury (Hg) speciation at the FGD inlet, the flue gas composition, and the sulphur dioxide (SO2) capture efficiency. A preliminary statistical analysis of data from 17 full-scale wet FGDs connects flue gas compositions, the extents of Hg oxidation at FGD inlets, and Hg retention efficiencies. These connections clearly signal that solution chemistry within the FGD determines Hg retention. A more thorough analysis based on thermochemical equilibrium yields highly accurate predictions for total Hg retention with no parameter adjustments. For the most reliable data, the predictions were within measurement uncertainties for both limestone and Mg/lime systems operating in both forced and natural oxidation mode. With the U.S. Environmental Protection Agency's (EPA) Information Collection Request (ICR) database, the quantitative performance ...
In this paper an analysis will be performed to assess the economical competitiveness of Nuclear Power against other base load technologies. There are several plans to build more nuclear power plants in western countries; these plans are result among other things of the fossil fuel high prices and the concern for the global warming. France started the construction of one EPR at Flamanville in 2007 and at the end of 2008 there were 17 applications before NRC for construction and operation licenses (COL) to build as much as 26 new reactor units in USA, among the designs selected are the US-EPR, APWR, ESBWR, ABWR and AP1000. Currently, there is a lot of uncertainty about what is the overnight cost for a new generation III nuclear power plant and the vendors are not providing too much information. However, it is expected that under the new economy conditions the overnight cost will be between 2500 and 3500 USD/kW, the output electricity power of the units mentioned ...
In this thesis, the potential to discover supersymmetric signatures in both e"+e"- and #gamma##gamma# colliders evaluated with a Monte Carlo analysis, is discussed. The analysis was focused on the detection of muons, essentially. First, we study the detection of #mu#"+_R#mu#"-_R in e"-e"+ collisions, whose purpose is the measurement of the #mu#_R mass. It was found that an uncertainty of 0.11 GeV (stat) can be achieved. Under the assumption of the real conditions of the ILC photon collider, a study covering the detection of #mu#"+_R#mu#"-_R and #mu#"+_L#mu#"-_L pairs for #sq root#(s_e_"-_e_"+)=0.5 and 0.6 TeV was performed. According to the simulation, a statistical error for the branching ratios of #mu#"#+-#_L#->##chi#"0_1#mu#"#+-# of 0.98% and #mu#"#+-#_L#->##chi#"0_2#mu#"#+-# of 3.97% can be reached. In order to judge the Monte Carlo results, we have used a technique based on a multidimensional fit to evaluate the impact of the ...
Restructured power markets require concepts not only for extending the lifetime of existing plants, but also concepts for reducing the life-cycle costs of existing older steam power plants in order to remain competitive with the most modern and advanced power generation technology such as combined cycle power plants. Out of the broad range of methods to extend service life and increase availability, and to increase power output and efficiency, this paper focuses on full repowering. Full repowering replaces the old fired boiler with gas turbine(s) and heat-recovery steam generators (HRSG) as heat input to the existing bottoming cycle and reuses the steam turbine (ST) condenser and further balance of plant (BOP) equipment. The potential offered by this concept is demonstrated. Repowering and modernization projects are executed if they result in economic benefits for the operator. Investment decisions need to be prepared based on an estimate or proof of an adequate return on investment ...
The purpose of this work is to determine the extent to which drill water might be expected to be imbibed by core samples taken from densely welded tuff. In a related experimental study conducted in G-Tunnel, drill water imbibition by the core samples was observed to be minimal. Calculations were carried out with the TOUGH code with the intent of corroborating the imbibition observations. Due to the absence of hydrologic data pertaining directly to G-Tunnel welded tuff, it was necessary to apply data from a similar formation. Because the moisture retention curve was not available for imbibition conditions, the drainage curve was applied to the model. The poor agreement between the observed and calculated imbibition data is attributed primarily to the inappropriateness of the drainage curve. Also significant is the value of absolute permeability (k) assumed in the model. Provided that the semi-log plot of the drainage and imbibition moisture retention curves are parallel within the ...
We discuss various reactions at future e"+e"- and #gamma##gamma# colliders involving real (beamstrahlung or backscattered laser) or quasi-real (bremsstrahlung) photons in the initial state and hadrons in the final state. The production of two central jets with large transverse momentum p_T is described in some detail; we give distributions for the rapidity and p_T of the jets as well as the di-jet invariant mass, and discuss the relative importance of various initial state configurations and the uncertainties that arise from the at present rather poor knowledge of the parton content of the photon. We also present results for 'mono-jet' production where one jet goes down a beam pipe, for the production of charm, bottom and top quarks, and for single production of W and Z bosons. Where appropriate, the two-photon processes are compared with annihilation reactions leading to similar final states. We also argue that the behaviour of the total inelastic #gamma##gamma# ...
Some of the methodologies, techniques, dependencies and lessons learned regarding the year 2000 (Y2K) project currently underway at PanCanadian are described. The Y2K problem, which is a date related malfunction associated with the turn of the century, may affect computers and automated control systems. The cost of fixing this world wide problem ranges from $52 billion to $2 trillion. At PanCanadian, central to ensuring that the entire corporation is ready for the Year 2000 is a dedicated project team in the information technology (IT) department who manage all the life-cycle software for the company. IT staff purchase, install and remove all obsolete software and data. Inventory, testing and remediation of all software, hardware and embedded systems are the basis of the plan of action adopted by the I.T. Y2K project team. Dealing with Y2K problems of business partners, and planning for business interruption are special problems for which different approaches have been adopted. ...
Ophir Corporation was awarded a contract by the U. S. Department of Energy, National Energy Technology Laboratory under the Project Title ''Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipeline Leak Detection'' on October 14, 2002. This second six-month technical report summarizes the progress made towards defining, designing, and developing the hardware and software segments of the airborne, optical remote methane and ethane sensor. The most challenging task to date has been to identify a vendor capable of designing and developing a light source with the appropriate output wavelength and power. This report will document the work that has been done to identify design requirements, and potential vendors for the light source. Significant progress has also been made in characterizing the amount of light return available from a remote target at various distances from the light source. A great deal of time has been spent ...
Selecting the best bit for an application is a difficult task because a large number of variables can influence bit performance, therefore upon a decision to run a particular bit type based solely on the average measurements of previous bit performances can lead to a very important impact on the drilling cost. Bits are designed with different concepts and that recent technological advances allow them to be used in a wider range of applications that could improve their drilling programs. Rather than a deterministic estimate, a more mature view of a bit performance is a presentation of possible outputs (bits longevity in drilled meters, rate of penetration, bit cost and cost per meter) in recognition of the uncertainty associated with drilling wells. An evaluation of a simple model based on the drilling cost equation indicates the sensitivity of each variable - described here by its probability distribution function - on the bottom line and can ...
The titanium stabilized austenitic steel similar to the type of 321 is sensitive to the stress corrosion crackingunder horizontal steam generator operating condition. SCC was observed under crevice corrosion parameters and has resulted in the transgranular or intergranular cracking at the both, components primary collectors and heat exchange tubes. The crevice environment is characterized by aggressive impurities and 'non aggressive' compounds. Sulfates and chlorides as aggressive species and silicates and alumino-silicates as 'non aggressive' species on the other hand are present in significant amount in the crevice environment under operating condition. Local water chemistry parameters were evaluated with MULTEQ Code. As input data the measured operational values of local and bulk environments have been used. The determined parameters were compared with the results of thread hole environment analyses and tube surface investigations respectively. ...
Tritium occurs in nature in trace amounts, but its concentration is changing due to natural and artificial sources. Studies focusing on natural tritium have to take into account the effect of artificial sources. Also, the impact of tritium is an important issue in environmental protection, e.g. in connection with the emissions from nuclear power plants. The present work focuses on the rain washout of tritium emitted from the Paks nuclear power plant in Hungary. Rainwater collectors were placed around the plant and after a period of precipitation, rainwater was collected and analysed for tritium content. Samples were analysed using low-level liquid scintillation counting, with some also subject to the more accurate "3He ingrowth method. The results clearly show the trace of the tritium plume emitted from the plant; however, values are only about one order of magnitude higher than environmental background levels. A washout model was devised to ...
Recently, independent system operators (ISOs) and others have published reports on the costs of transmission congestion. The magnitude of congestion costs cited in these reports has contributed to the national discussion on the current state of U.S. electricity transmission system and whether it provides an adequate platform for competition in wholesale electricity markets. This report reviews reports of congestion costs and begins to assess their implications for the current national discussion on the importance of the U.S. electricity transmission system for enabling competitive wholesale electricity markets. As a guiding principle, we posit that a more robust electricity system could reduce congestion costs; and thereby, (1) facilitate more vibrant and fair competition in wholesale electricity markets, and (2) enable consumers to seek out the lowest prices for electricity. Yet, examining the details suggests that, sometimes, there will be trade-offs between ...
Uncertainty in computer vision can arise at various levels. It can occur in the low level in the raw sensor input, and extends all the way through intermediate and higher levels. Ideally, at any level where decisions are being made on the basis of previous processing steps, a computer vision system must have sufficient flexibility for representation of uncertainty in any of these levels. The input cue representation portion of a computer vision system should maintain the information content of the original input images, while at the same time allowing for uncertainty in the identification of attributes required by other parts of the system for decision making. Processes such as edge detection, segmentation, and shape matching yield results which could bias higher level decision making, unless some framework is defined for the representation of uncertainty in the context of fuzzy set theory where ...
In designing power system stabilizer (PSS), a major difficulty is to successfully treat the system`s uncertainties. These uncertainties arise because of changes in operating conditions, approximations in modeling, parameter variations caused by faults, etc. It is known that in the presence of uncertainties, conventional methodologies such as linear optimal technique, adaptive controls, etc., may fail to guarantee the stability of the system. On the other hand, the H{infinity} control theory provides potential ability to overcome this problem. However, some limitations still exist in the treatment of uncertainty. That is, the existing standard H{infinity}-PSSs cannot adequately treat the system uncertainties. Moreover, performance problems can arise in this approach due to the pole-zero cancellation phenomenon. To deal with the above mentioned limitations, a new design methodology ...
Inventories of emissions and removals of greenhouse gases will be used under the United Nations Framework Convention on Climate Change and the Kyoto Protocol to demonstrate compliance with obligations. During the negotiation process of the Kyoto Protocol it has been a concern that uptake of carbon in forest sinks can be difficult to verify. The reason for large uncertainties are high temporal and spatial variability and lack of representative estimation parameters. Additional uncertainties will be a consequence of definitions made in the Kyoto Protocol reporting. In the Nordic countries the national forest inventories will be very useful to estimate changes in carbon stocks. The main uncertainty lies in the conversion from changes in tradable timber to changes in total carbon biomass. The uncertainties in the emissions of the non-CO{sub 2} carbon from forest soils are particularly high. On the other ...
We summarize our lattice QCD study of the form factor at zero recoil in the decay {bar B} {yields} D*{ell}{bar {nu}}. After careful consideration of all sources of systematic uncertainty, we find, h{sub A{sub 1}}(1) = 0.913{sub -17-30}{sup +24+17}, where the first uncertainty is from statistics and fitting while the second combined uncertainty is from all other systematic effects.
The Kyoto Protocol foresees emission trading but does not yet specify verification of (uncertain) emissions. This paper analyses a setting in which parties can meet their emission targets by reducing emissions, by investing in monitoring (reducing uncertainty of emissions) or by (bilaterally) trading permits. We derive the optimality conditions and carry out various numerical simulations. Our applications suggest that including uncertainty could increase compliance costs for the USA, Japan and the European Union. Central Europe and the Former Soviet Union might be able to gain from trading due to higher permit prices. Emissions trading could also lower aggregate uncertainty on emissions.
This research aims to develop reliable, advanced system thermal-hydraulic computer code and to quantify the uncertainties of code to introduce the best estimate methodology of ECCS for LBLOCA. Although the one of best estimate code, RELAP5/MOD3.1 was introduced from USNRC, several deficiencies in its reflood model and some improvements have been made. The improvements consist of modification of reflood wall heat transfer package and adjusting the drop size in dispersed flow regime. The tome smoothing of wall vaporization and level tracking model are also added to eliminate the pressure spike and level oscillation. For the verification of improved model and quantification of associated uncertainty, the FLECHT-SEASET data were used and upper limit of uncertainty at 95% confidence level is evaluated. (Author) 30 refs., 49 figs., 2 tabs.
This article examines how politics and science interacted against a background of uncertainty to shape policy in the case of environmental contamination by polybrominated biphenyls (PBB) in Michigan....Full Text Available
... The third series used a correlated parameter covariance matrix derived from a generic database of modeling uncertainty for space structures [5-1 ...
Subcritical experiments using californium source-driven noise analysis (CSDNA) and Feynman variance-to-mean methods were performed with an alpha-phase plutonium sphere reflected by nickel shells, up to a maximum thickness of 7.62 cm. Both methods provide means of determining the subcritical multiplication of a system containing nuclear material. A benchmark analysis of the experiments was performed for inclusion in the 2010 edition of the International Handbook of Evaluated Criticality Safety Benchmark Experiments. Benchmark models have been developed that represent these subcritical experiments. An analysis of the computed eigenvalues and the uncertainty in the experiment and methods was performed. The eigenvalues computed using the CSDNA method were very close to those calculated using MCNP5; however, computed eigenvalues are used in the analysis of the CSDNA method. Independent calculations using KENO-VI provided similar eigenvalues to those determined using the ...
An uncertainty decrease is an very important issue for enhancing risk-informed (RI) activities worldwide. Especially, a relatively large uncertainty in a level-2 (L2) PSA risk compared with level-1 internal PSA risk has been a bottleneck problem in the RI application to the extent of a severe accident management. According to the ASME PRA standard in which sources of an uncertainty to capture a category-II RI (= Option 2) capability are listed, an uncertainty analysis which identifies the key sources of an uncertainty and includes sensitivity studies for dominant contributors to LERF (Large Early Release Frequency) needs to be provided. To solve these problems, USNRC have developed the 'SPAR-LERF' model related to the L2 RI application and 'L2 uncertainty assessment and improvement' work is being taken as a main PSA2 topic of ...
In this study, a regional dynamical model (WRF) is used to drive biogenic emission models to calculate high resolution (10 x 10 km) biogenic emissions of isoprene (C_5H_8), monoterpenes (C_1H_1_6), and nitric oxide (NO) in China. This high resolution biogenic inventory will be available for the community to study the effect of biogenic emissions on photochemical oxidants in China. The biogenic emissions are compared to anthropogenic emissions to gain insight on the potential impact of the biogenic emissions on tropospheric chemistry, especially ozone production in this region. The results show that the biogenic emissions in China exhibit strongly diurnal, seasonal, and spatial variations. The isoprenoid (including both isoprene and monoterpenes) emissions are closely correlated to tree density and strongly vary with season and local time. During winter (January), the biogenic isoprenoid emissions are the lowest, resulting from lower temperature and solar radiation, ...
The use of standard cementitious material creates pulses of pH in the magnitude of 12-13 in the leachates and release alkalis. Such a high pH is detrimental and also unnecessarily complicates the safety analysis of the repository. As no reliable pH-plume models exist, the use of products giving a pH below 11 in the leachates facilitates the safety analysis. Also, according to current understanding, the use of low-pH cement (pH = 11) will not disturb the functioning of the bentonite, although limiting the amount of low-pH cement is recommended. A result of the project is that there are both low-pH cementitious material for grouting larger fractures (= 100 {mu}m) and non-cementitious material for grouting smaller fractures (< 100 {mu}m) that will, after further optimisation work, be recommended for grouting of deep repositories. This project concentrated on the technical development of properties for the low pH grouts. Long-term safety and environmental ...
The molar heat capacities (Cp,m) of a series of synthetic forsterite (Fo)-fayalite (Fa), (Mg2SiO4+Fe2SiO4), olivines have been measured between 5K and 300K on milligram-sized samples with the Physical Properties Measurement System (Quantum Design(R)). Sharp, ?-type heat capacity anomalies are observed in the Fe-rich compositions fayalite, Fo10Fa90, Fo20Fa80, Fo30Fa70, and Fo40Fa60. The corresponding Neel temperatures TN decrease linearly from 64.5K in fayalite to 32.8K in Fo40Fa60 following the relationship TN=79.02.xFa-14.07. Fo50Fa50 and Mg-richer olivines show weak broad features in the heat capacity data around 15K to 20K that decrease in magnitude with increasing forsterite content. In order to derive and separate molar electronic, magnetic and vibrational heat capacity contributions, Cel,m, Cmag,m, and Cvib,m from the experimental heat capacities (Ctot,m), we used a single-parametric phonon dispersion model to calculate Cvib,m for the solid-solution members ...
Recently the ISO standards organization has requested the PV community to establish AMO calibration methodologies for space solar cells. The PV community responded by organizing a series of workshops to review and recommend AMO calibration techniques. One of the activities of the workshop is to review the various calibration methodologies and conduct a comprehensive uncertainty analysis of each method. This paper outlines NASA`s methodology of AMO calibration using the high altitude aircraft method.
Over the past two decades, quantum computing has become a popular and promising approach to trying to solve computationally difficult problems. Missing in many descriptions of quantum computing is just how probability enters into the process. Here, we discuss some simple examples of how uncertainty and probability enter, and how this and the ideas of quantum computing challenge our interpretations of quantum mechanics. It is found that this uncertainty can lead to intrinsic decoherence, and this raises challenges for error correction. (viewpoint)
Literature references related to definition, generation, and use of evaluated cross section uncertainty (variance-covariance) files are listed with comments intended primarily to guide the reader toward materials of immediate interest. Papers are also cited that cover covariance information for individual experiments and that relate to production and use of multigroup covariance matrices. Titles are divided among several major categories.
ObjectivesTo assess the magnitude of cigarette smuggling after the market opened in Taiwan.MethodsReview of tobacco industry documents for references...Full Text Available
Some factors affecting the accuracy of magnitude calibration of palaeoearthquakes are discussed. The general problem is illustrated by two case studies. First, the 2003 strong earthquake in the Altai region (Russia-Mongolia border), which has generated co-seismic surface faulting is considered. An analysis is conducted to determine how accurately its magnitude could be defined after 2000 years based on surface faulting parameters, retrieved when future palaeoearthquake studies are launched. This example demonstrates that accurate evaluation of magnitude is possible if specific regional seismotectonic features are taken into account and surface faulting parameters are measured over a dense grid. Next, the Muya earthquake that occurred in the Baikal seismic region in 1957 is studied with res...
... these features and yields results which are two orders of magnitude faster than those available using conventional numerical ray tracing techniques ...
Two additional earthquakes, magnitudes 6.6 and 6.7 occurred the next morning. The first earthquake was located six miles north of Petrolia, California, ...
BackgroundThe function of a cylinder allowing simultaneous measurements of the opposition axis of the index finger and thumb of the hand and the magnitude of pinch force is described.Full Text Available
The aim of this work is the evaluation of the quality of a chemistry-transport model, not by a classical comparison with observations, but by the estimation of its uncertainties due to the input data, to the model formulation and to the numerical approximations. The study of these 3 sources of uncertainty is carried out with Monte Carlo simulations, with multi-model simulations and with comparisons between numerical schemes, respectively. A high uncertainty is shown for ozone concentrations. To overcome the uncertainty-related limitations, a strategy consists in using the overall forecasting. By combining several models (up to 48) on the basis of past observations, forecasts can be significantly improved. This work has been also the occasion of developing an innovative modeling system, named Polyphemus. (J.S.)
There are two kinds of uncertainties in safety assessment of engineering structures. One is of the nature of randomness, and the other fuzziness. Fuzzy uncertainties exist in defining certain structural performances, conditions, parameters, and their interrelationships. The theory of fuzzy sets should be employed to cope with the fuzzy uncertainties. In this paper, a general definition for structural failure considering the fuzzy uncertainties is introduced firstly. Failure of the structure is modelled by a fuzzy event, and described by the membership function. The limit state surface is then replaced by a fuzzy limit state zone, in which every point represents a state belonging to the failure with a certain degree of membership. Then a fuzzy optimization problem for solving the reliability index is formulated. In classical structural reliability theory, the reliability index is defined by the minimum ...
In this work, we use lasers to enhance possibilities of laser desorption methods and to optimize coating procedure for capillary electrophoresis (CE). We use several different instrumental arrangements to characterize matrix-assisted laser desorption (MALD) at atmospheric pressure and in vacuum. In imaging mode, 488-nm argon-ion laser beam is deflected by two acousto-optic deflectors to scan plumes desorbed at atmospheric pressure via absorption. All absorbing species, including neutral molecules, are monitored. Interesting features, e.g. differences between the initial plume and subsequent plumes desorbed from the same spot, or the formation of two plumes from one laser shot are observed. Total plume absorbance can be correlated with the acoustic signal generated by the desorption event. A model equation for the plume velocity as a function of time is proposed. Alternatively, the use of a static laser beam for observation enables reliable determination of plume velocities even when ...
The study examines the isothermal fatigue properties of novel ODS iron-base or nickel-base superalloys at temperatures of 850 C and 1050 C. The materials are different in grain structure and texture, so that particularly the effects of grain structures and textures can be studied. In order to also perform examinations of creep-fatigue interactions, various load cycles are applied. It is shown that the LCF-affected life of the grain structures of both alloy types is determined by the elastic modulus. The cyclic lifetimes determined by the conventional Manson-Coffin method for both alloy types exhibit differences of up to two orders of magnitude. Using the product of the total strain range and the elastic modulus, however, will yield precise life predictions. Under conditions of LCF stress only, the grain structure has no effect on the materials` service life, other than in the case of creep-fatigue, but the grain structure has a decisive influence on the damage ...
We study heavy physics effects on the Higgs production in #gamma##gamma# fusion using the effective Lagrangian approach. We find that the effects coming from new physics may enhance the standard model predictions for the number of events expected in the final states b-barb, WW, and ZZ up to one order of magnitude, whereas the corresponding number of events for the final state t-bart may be enhanced up to two orders of magnitude.
Incomplete convergence in numerical simulation such as computational physics simulations and/or Monte Carlo simulations can enter into the calculation of the objective function in an optimization problem, producing noise, bias, and topo- graphical inaccuracy in the objective function. These affect accuracy and convergence rate in the optimization problem. This paper is concerned with global searching of a diverse parameter space, graduating to accelerated local convergence to a (hopefully) global optimum, in a framework that acknowledges convergence uncertainty and manages model resolu- tion to efficiently reduce uncertainty in the final optimum. In its own right, the global-to-local optimization engine employed here (devised for noise tolerance) performs better than other classical and contemporary optimization approaches tried individually and in combination on the "industrial" test problem to be presented.
Air toxics from the industrial wastewater treatment plants (IWTPs) impose serious health concerns on its surrounding residential neighborhoods. To address such health concerns, one of the key challenges is to quantify the air emissions from the IWTPs. The objective here is to characterize the air emissions from the IWTPs and quantify its associated uncertainty. An IWTP receiving the wastewaters from an airplane maintenance facility is used for illustration with focus on the quantification of air emissions for benzyl alcohol, phenol, methylene chloride, 2-butanone, and acetone. Two general fate models, i.e., WATER9 and TOXCHEM+V3.0 were used to model the IWTP and quantify the air emissions. Monte Carlo and Bootstrap simulation were used for uncertainty analysis. On average, air emissions fr...
As a contribution to the US/Japan cooperative program in fusion neutronics, we have prepared a library of multigroup neutron cross sections, scattering matrices, and covariances (uncertainties and their correlations). This 74-group library, called COVFILS-2, is being used at Los Alamos and at the University of California at Los Angeles in the sensitivity and uncertainty analysis of the Li_2O integral experiment recently performed at the Fast Neutron Source (FNS) in Japan. Another intended use of this library is in the estimation of the uncertainty in key performance parameters (such as breeding ratio) of conceptual fusion reactors. The 14 materials included in the first version of COVFILS-2 are H, "6Li, "7Li, Be, C, N, O, Na, Al, Si, Cr, Fe, Ni, and Pb.
Nat'l Training Center Contact Us Directory Email Us BLM > Socioeconomic Impacts > Timber Print Page Socioeconomic Impacts from Timber BLM-administered lands yielded $337...
Wade. Jackson. - Army. VTD at NASA. Langley. ABSTRACT. Panel size has a large effect on the impact response and resultant damage level of honeycomb sandwich ...
This poster, submitted for the CU Energy Initiative/NREL Symposium on October 3, discusses the impacts of renewable fuel and electricity standards on state economies.
This paper presents experimental data and an computational model of the cold spray solid particle impact process. Copper particles impacting onto a polished stainless steel substrate are examined. The high velocity impact causes significant plastic deformation of both the particle and the sub- strate, but no melting is observed. The plastic deformation exposes clean surfaces that, under the high impact pressures, result in significant bond strengths between the particle and substrate. Experimental measurements of the splat and crater sizes compare well with the numerical calculations. It is shown that the crater depth is significant and increases with impact velocity. However, the splat diameter is much less sensitive to the impact velocity. It is also shown that the geometric lengths of the splat and crater scale linearly with the diameter of the ...
ObjectiveTo evaluate the impact of an interconceptional antibiotic regimen on the endometrial microbial flora and histology.Study DesignFull Text Available
Abstract: We present a generic scoring system that compares the impact of alien species among members of large taxonomic groups. This scoring can be used to identify the most harmful alien species so that conservation measures to ameliorate their negative effects can be prioritized. For all alien mammals in Europe, we assessed impact reports as completely as possible. Impact was classified as either environmental or economic. We subdivided each of these categories into five subcategories (environmental: impact through competition, predation, hybridization, transmission of disease, and herbivory; economic: impact on agriculture, livestock, forestry, human health, and infrastructure). We assigned all impact reports to one of these 10 categories. All categories had impact scores that ranged f...
The UK government's economy-wide 60% carbon dioxide reduction target by 2050 requires a paradigm shift in the whole energy system. Numerous analytical studies have concluded that the power sector is a critical contributor to a low carbon energy system, and electricity generation has dominated the policy discussion on UK decarbonisation scenarios. However, range of technical, social and market challenges, combined with alternate market investment strategies mean that large scale deployment of key classes of low carbon electricity technologies is fraught with uncertainty. The UK MARKAL energy systems model has been used to investigate these long-term uncertainties in key electricity generation options. A range of power sector specific parametric sensitivities have been performed under a 'what-if' framework to provide a systematic exploration of least-cost energy system configurations under a broad, integrated set of ...
The UK government's economy-wide 60% carbon dioxide reduction target by 2050 requires a paradigm shift in the whole energy system. Numerous analytical studies have concluded that the power sector is a critical contributor to a low carbon energy system, and electricity generation has dominated the policy discussion on UK decarbonisation scenarios. However, range of technical, social and market challenges, combined with alternate market investment strategies mean that large scale deployment of key classes of low carbon electricity technologies is fraught with uncertainty. The UK MARKAL energy systems model has been used to investigate these long-term uncertainties in key electricity generation options. A range of power sector specific parametric sensitivities have been performed under a 'what-if' framework to provide a systematic exploration of least-cost energy system configurations under a broad, integrated set of input assumptions. In this ...
This paper presents the conceptual framework that is being used to define quantification of margins and uncertainties (QMU) for application in the nuclear weapons (NW) work conducted at Sandia National Laboratories. The conceptual framework addresses the margins and uncertainties throughout the NW life cycle and includes the definition of terms related to QMU and to figures of merit. Potential applications of QMU consist of analyses based on physical data and on modeling and simulation. Appendix A provides general guidelines for addressing cases in which significant and relevant physical data are available for QMU analysis. Appendix B gives the specific guidance that was used to conduct QMU analyses in cycle 12 of the annual assessment process. Appendix C offers general guidelines for addressing cases in which appropriate models are available for use in QMU analysis. Appendix D contains an example that highlights the consequences of different ...
The quantitative experimental uncertainty in the structure of fully hydrated, biologically relevant, fluid (Lα) phase lipid bilayers has been too large to...Full Text Available
... uncertainty. The method is applied for the invasive shrub Rosa rugosa (Japanese rose) in Danish fixed dunes. The probability ... habitat code 2130). In 14 sites, the invasive shrub Rosa rugosa was recorde...
The status of the electroweak Standard Model is reviewed in the light of recent precision data and new theoretical results which have contributed to improve the predictions for precision observables, together with the remaining inherent theoretical uncertainties. Consequences for possible new physics are also discussed.
The E and P industry has high levels of uncertainty and risk, which oil companies attempt to quantify before embarking on each individual E and P project. However, the actual return on investment often falls well short of the hurdle rate. This discrepancy has been attributed to systemic limitations in decision analysis processes and workflow, which result in repeated underestimation of risk and overestimation of the predicted production of the project. Well designed decision analysis processes in association with clearly defined, multi-scenario analyses of significant technical uncertainties are required. However, simulation of these uncertainties is not realistic given the performance and infrastructure limitations of conventional technology (Begg et al., 2001; Floris and Peersmann, 2000). During the past five years, more than 20 companies have attempted to map the requirements of new technology that is needed to improve ...
Cancer treatment with ionizing radiation is often compromised by organ motion, in particular for lung cases. Motion uncertainties can significantly degrade an otherwise optimized treatment plan....Full Text Available
The aim of this project was to develop an understanding of the dynamical processes that evolve within an electric utility firm, and without it. This volume covers organizational dynamics and control, and planning under uncertainty. (DLC)
... (restricted)] 256-264 Influence of likelihood function choice for estimating crop model parameters using the generalized likelihood uncertainty estimation method by He, Jianqiang & Jones, James W. & Graham, Wendy D. & Dukes, Michael D. [Downloadable! (restricted)]...
The GBM location uncertainties range from 5-15deg (radius, 1 sigma, stat+sys). ... The site's dis/enabling on Notice types and their other filter criteria .... Fermi Pointing Direction Notice gives the current pointing direction of the ...
Rodent models have been extensively utilized to identify putative human immunotoxicants; however, even when immunotoxicity is established, uncertainty remains whether the effects are predictive of human...Full Text Available
... Southall et al. 2007). However, based on preliminary simulation modeling that attempted to allow for various uncertainties in ... 1986. Behavioral responses of gray whales to industrial noise:
The author have prepared a new, fusion-oriented library of multigroup neutron cross sections, scattering matrices, and covariances (uncertainties and correlations). The 74-group library, called COVFILS-2, has been used, or will be used, by neutronics groups at Los Alamos National Lab. (LANL) at the University of California at Los Angeles, and at the Swiss Federal Institute for Reactor Research in the sensitivity and uncertainty analysis of fusion-relevant integral experiments such as the Li/sub 2/O experiment performed at the Fast Neutron Source Facility in Japan and the Lithium breeding module experiment planned at the LOTUS facility in Lausanne, Switzerland. Another intended use of this library is in the estimation of the uncertainty in key performance parameters (such as the breeding ratio) of conceptual fusion reactors. The 14 materials included in the first version of COVFILS-2 are hydrogen, /sup 6/Li, /sup 7/Li, ...
The author have prepared a new, fusion-oriented library of multigroup neutron cross sections, scattering matrices, and covariances (uncertainties and correlations). The 74-group library, called COVFILS-2, has been used, or will be used, by neutronics groups at Los Alamos National Lab. (LANL) at the University of California at Los Angeles, and at the Swiss Federal Institute for Reactor Research in the sensitivity and uncertainty analysis of fusion-relevant integral experiments such as the Li_2O experiment performed at the Fast Neutron Source Facility in Japan and the Lithium breeding module experiment planned at the LOTUS facility in Lausanne, Switzerland. Another intended use of this library is in the estimation of the uncertainty in key performance parameters (such as the breeding ratio) of conceptual fusion reactors. The 14 materials included in the first version of COVFILS-2 are hydrogen, "6Li, "7Li, beryllium, carbon, ...
After discrimination training on a multiple variable-interval extinction schedule of food reinforcement, pigeons were placed on the uncued or mixed version of the same schedule and allowed to make...Full Text Available
and a flyby of the asteroid Ida, the enhanced filter is shown to substantially improve the ... twoway range, and ADOR data points acquired at S-band frequencies. .... The result of this fit and its l-sigma uncertainty ellipse is ...
In many radiotherapy clinics, geometric uncertainties in the delivery of 3D conformal radiation therapy and intensity modulated radiation therapy of the prostate are reduced by aligning the...Full Text Available
An experimental and analytical study was performed to improve understanding of the dynamic impact behavior of carbon steel pipes. The test program addressed two types of pipe impact scenarios using both 2- and 4-in. Sch-80 pipes and elbows. Projectile-on-pipe tests simulated the behavior of a stationary target pipe which is impacted at its center by a larger, more rigid whipping pipe. These target pipes, which contained non-flowing water at about 290{degree}C temperature and ca 8.5 megapascals pressure, exhibited a peak deformation of up to 45% reduction in their diameter. For each test condition, the local deformation at the impact zone is a function of the peak impact force and impact velocity. Pipe-on-wall tests simulated the impact of an elbow at the free end of a cantilevered whipping pipe with a rigid barrier. The peak crush of the ...
Amongst the minor actinides issued from the spent nuclear fuel, {sup 241}Am is present in high concentration and contributes significantly to the long-term radiotoxicity of nuclear waste. A major uncertainty was present in the transmutation chain of {sup 241}Am when irradiated by a high intensity thermal neutron flux. This uncertainty was brought about by the poor knowledge of the {sup 242gs}Am neutron capture cross section. A dedicated experiment has been performed at the Institut Laue-Langevin in Grenoble, which gives a definitive experimental answer to this problem.
Amongst the minor actinides issued from the spent nuclear fuel, "2"4"1Am is present in high concentration and contributes significantly to the long-term radiotoxicity of nuclear waste. A major uncertainty was present in the transmutation chain of "2"4"1Am when irradiated by a high intensity thermal neutron flux. This uncertainty was brought about by the poor knowledge of the "2"4"2"g"sAm neutron capture cross section. A dedicated experiment has been performed at the Institut Laue-Langevin in Grenoble, which gives a definitive experimental answer to this problem.
The Daya Bay reactor neutrino experiment is located at the Daya Bay nuclear power plant in Shenzhen, China. The experiment deploys eight 'identical' antineutrino detectors to measure antineutrino fluxes from six 2.9 GWth reactor cores in three underground experimental halls at different distances. The target zone of the Daya Bay detector is filled with 20 t 0.1% Gd doped LAB liquid scintillator. The baseline uncorrelated detector uncertainty is ?0.38% using current experimental techniques. Daya Bay can reach a sensitivity of sin22?13<0.01 with baseline uncertainties after 3 years of data taking.
Yucca Mountain, Nevada is a potential site for a high-level radioactive-waste repository. Uncertainty and sensitivity analyses were performed to estimate critical factors in the performance of the site with respect to a criterion in terms of pre-waste-emplacement ground-water travel time. The degree of failure in the analytical model to meet the criterion is sensitive to the estimate of fracture porosity in the upper welded unit of the problem domain. Fracture porosity is derived from a number of more fundamental measurements including fracture frequency, fracture orientation, and the moisture-retention characteristic inferred for the fracture domain.
Neutron spectra measured in the FFTF In-Reactor Thimble (IRT) by proton recoil proportional counters, proton recoil emulsions, and passive dosimeters have been evaluated and compared with each other and with three-dimensionl diffusion theory calculated spectra for the purpose of validating the passive dosimeter spectrum adjustment technique. The least squares data adjustment code, FERRET, was used to combine measured reaction rates, calculated spectra, and dosimeter cross sections, resulting in adjusted spectra and cross sections with uncertainties and correlations that properly account for uncertainties and correlations on the input parameters.
A model-based technique incorporating neural networks has been developed for process monitoring. The technique is intended for processes where the uncertainty in the reference model is larger than desired but where process measurements providing additional information about the behavior of the system are available. This data is used to reduce the uncertainty of the model. The technique has been implemented in a real-time system for monitoring operational changes of mechanical equipment for use in predictive maintenance applications. Tests on a peristaltic pump were conducted and demonstrate the advantages of the proposed technique.
The reasons for including variance-covariance information in evaluated nuclear data files are reviewed. Accomplihments and obstacles in meeting these needs are identified. The capability to develop and utilize evaluated cross-section covariance files has been largely demonstrated, but comprehensive files of soundly based covariance data remain to be evaluated and not all types of cross-section data have yet been included. The status of the ENDF-VI covariance formats is discussed. Priorities are suggested for further development. Most effort should be concentrated to fully develop the capability to estimate the nuclear data uncertainties in quantities calculated for a broad energy spectrum. 12 refs.
We study uncertainties surrounding competition on business networks and board games. We investigate these uncertainties using concepts of fuzzy logic and game theory. We investigate how the payoff of the players is affected by a number of factors. These include the level of connectivity or number of links, the number of competitors, possible constraints on the networks and on the boards, as well as choice of strategy adopted by competitors. We introduce one fuzzy player in the game. This player uses fuzzy rules to make strategic decisions. We introduce learning to train and analyze how the fuzzy player adapts over time during the game.
Monte Carlo criticality calculations have been performed for over 50 years for reactor physics and criticality safety applications. With today's faster computers, these calculations are being carried out to greater precision (smaller uncertainties) in keff, and detailed distributions of power and reaction rates are being computed routinely. This paper provides a review of the fundamental theory of Monte Carlo criticality calculations, with guidance on practical methods for: (1) assuring convergence of both keff and the source distribution, (2) minimizing the bias in keff and reaction rate distributions, and (3) dealing with the under-prediction bias in uncertainties for keff and reaction rate distributions. (authors)
Qualitative interpretation of data of different nature and sources, based on segmentation techniques such as discriminant analysis, is useful to characterize and monitor hydrocarbon reservoirs. In order to make this interpretation more reliable, it is necessary to characterize uncertainties attached to data and then, to propagate them in the interpretation work-flow. In this thesis, uncertainties are represented by intervals, because usually, little is known about input data errors. The uncertainty characterization issue is dealt with specifically for each case study. The uncertainty propagation issue is treated by a new technique, based on interval analysis, which consists in extending to intervals various popular approaches (non parametric, quadratic and linear) to discriminant analysis: Firstly, a learning phase allows calibrating an imprecise classifying model on the basis of pre-interpreted data. ...
The moderate earthquake of magnitude 5.2 was occurred at the offshore Uljin on the 29 May 2004. The magnitude of the event is the largest one which is equal to that of the Sokrisan earthquake on the 16 September 1978 since the beginning of the instrumental recording by the Korean Metrological Administration (KMA) in 1978. The magnitude of the event was large enough to be felt in a wide area of the southern Korea. It did not affect the safety of the Uljin nuclear power plant (NPP) site which is about 80 km away from the epicenter. In this article, we estimate source parameters of the event and evaluate preliminary seismic safety of the Uljin NPP site regarding the event as an empirical Green's function (EGF)
This investigation presents scale-up of a detailed heterogeneous geostatistical model to a full field reservoir simulation model, considering both single and two-phase flow properties. The model represents a typical low permeability Danish North Sea chalk reservoir and includes capillary pressure and saturation end-point variations. Two new up-scaling methods has been investigated, all based on fine scale simulation on a cross section of the geomodel. The first methods assumes piston style behaviour and a coupled viscosity is introduced into the basic Darcy`s equations. The second method is a modification of the JBN method traditionally applied in analysing results from core flooding experiments, which emerged as the most successful and therefore also the recommended method. 1. In addition to the up scaling work we review the Equivalent Radius Method for capillary pressure normalisation with explicit derivation of type functions for Maastrichtian and Danian chalk types. Implementation ...
The U.S. Department of Energy Order 435.1, Radioactive Waste Management, requires a disposal authorization statement authorizing operation (or continued operation) for low-level waste disposal facilities. In fulfillment of these requirements, a disposal authorization statement was issued on October 25, 1999, authorizing the Hanford Site to transfer, receive, possess, and dispose of low-level radioactive waste at the 200 East Area burial grounds and the 200 West Area burial grounds. One of the conditions is that monitoring plans for the 200 East Area and 200 West Area low-level burial grounds be written and approved by the Richland Operations Office. As a result of a record of decision for the Hanford Site Solid Waste Program and acceptance of the Hanford Site Solid Waste Environmental Impact Statement, the use of the low-level burial ground (LLBG) as a disposal facility for low-level and mixed low-level wastes has been restricted to lined trenches and the Navy ...
The cross section database for electron impact excitation and electron impact ionization for hydrogen beam kinetic energies greater than 100 eV was considered, giving for each particular process a reference to a recommended publication of cross sections, as well as the accuracy or estimated accuracy. The work is motivated by the application of neutral beam injection in magnetic confinement devices, such as large tokamaks. 9 refs, 2 figs.
Table of Contents: Executive Summary; Introduction; Data Sources; Industry Profile and Economic Baseline; Industry Compliance Costs; Industry Impacts; Additional Economic Impacts; Cost-Effectiveness; Environmental Impacts and Benefits; Social Costs and Be...
A separation phenomenon occurring during the Charpy impact test of API X80 pipeline steels was investigated in the present study. A detailed microstructural analysis of fractured impact specimens showed that the band structure of bainite elongated along the rolling direction worked as prior initiation sites for separations, and that the number and length of the separations increased with the increasing volume fraction of bainite. In the steels having high work hardenability, tearing-shaped separations were found because the hammer-impacted region was seriously hardened during the impact test, which led to the reduction in the impact toughness. As the test temperature decreased, the tendency toward separations increased, but separations were not found when the cleavage fracture prevailed at very low temperatures. These findings suggested that the formation of bainite and secondary ...
Quartz has a dissipation factor of approximately 10(-4), which is an order of magnitude less than that of the best glasses previously used to fabricate patch pipettes; it's dielectric constant of 3.8...Full Text Available
Eukaryotic genome size varies over five orders of magnitude; however, the distribution is strongly skewed toward small values. Genome size is highly correlated to a number of phenotypic traits, suggesting...Full Text Available
Related to other research on the effectiveness of flow boiling heat transfer augmentation using various types of turbulators this investigation comprises a definitive study of the effect of large discrete roughness elements on heat transfer over the entir...
An ultrasensitive laser-induced fluorescence detector was used with capillary electrophoresis for the study of 5-carboxy-tetramethylrhodamine. The raw signal from the detector provided roughly...Full Text Available
Brief exposures to red light induce far red-reversible changes of 5 to 10 millivolts magnitude in the upper 1 centimeter of etiolated Avena coleoptiles. The changes begin within 15...Full Text Available
Background:Childhood obesity is increasingly being observed with changing lifestyles of families. The magnitude of overweight ranges from 9% to 27.5% and obesity ranges...Full Text Available
Somatic radiation doses are recognized to be possible factors of carcinogenesis. In correctly performed mammography, however, even as screening test, the radiation dose does not reach such an order of magnitude that the benefit of the procedure as to prevention of breast cancer is called into question.
ObjectivesIn 2003, the Omani Ministry of Health Child Health Care Program initiated a national Birth Defects (BD) Register. This paper reviews the magnitude and risk factors of birth...Full Text Available
The electrode structure of an inverted cesium sputtering negative ion source has been modified to produce a convergent Cs/sup +/ beam. The intensities of negative ion beams produced with this electrode structure are approximately an order of magnitude greater than previously obtained.
The genetic architecture of complex traits underlying physiology and disease in most organisms remains elusive. We still know little about the number of genes that underlie these traits, the magnitude...Full Text Available
May 10, 2009 ... The estimated magnitude is 18.95 with a 1-sigma error of about 0.17. ... The points of contact for this burst is Masanori Ohno .... 80 seconds after the BAT trigger with a settling exposure in the UVOT v filter. ...
A prototype detector based on the inclined boron layer principle is introduced. For typical measurement conditions at the Liquids Reflectometer at the Spallation Neutron Source, its count rate capability is shown to be superior to that of the current detector by nearly two orders of magnitude.
In recent years, the National Toxicology Program (NTP) has selected numerous glycol ethers for testing in routine laboratory mammals to ascertain the magnitude of their ability to injure the conceptus....Full Text Available
BackgroundInadequate platelet inhibition despite aspirin and clopidogrel therapy during and after a percutaneous coronary intervention is associated with an impaired clinical outcome....Full Text Available
Body size variation across the Metazoa is immense, encompassing 17 orders of magnitude in biovolume. Factors driving this extreme diversification in size and the consequences of size variation for biological...Full Text Available
Thermal-hydraulics analysis can be used to determine location and magnitude of leaks inside a pressurized water reactor (PWR) containment, as required by plant technical specifications. The major advantage of this detection method is that it minimizes radiation exposure of maintenance personnel because most of the leak detection process is performed from the control room outside the containment. In addition, such a program allows for the elimination of pipe whip restraints and jet impingement shields, eliminating costs for maintenance of these supports and shields in older plants and lowering construction costs for new plants. Previously, only simple single-node containment models were used for determining leakage magnitude. This paper presents a more sophisticated multinode approach for determining the magnitude and location. The resulting sensitivities to leak can be programmed into the plant's computer system. ...
We present numerical calculations for cesium and mercury to estimate the sensitivity of the scattering length to the variation of the fine structure constant alpha. The method used follows ideas Chin and Flambaum [Phys. Rev. Lett. 96, 230801 (2006)], where the sensitivity to the variation of the electron to proton mass ratio, beta, was considered. We demonstrate that for heavy systems, the sensitivity to variation of alpha is of the same order of magnitude as to variation of beta. Near narrow Feshbach resonances the enhancement of the sensitivity may exceed nine orders of magnitude.
Aggregation of fine-resolution land-cover maps to coarser scales indicates that estimates of the proportions of land-cover types vary as a function of spatial resolution. The magnitude of these proportional errors in a forested area in northern California increase significantly as resolution exceeds a 90-m threshold. These errors could pose difficulties for the use of land-cover products generated from coarse-resolution sensors such as the NOAA-AVHRR and the MODIS sensor planned for the EOS program. The magnitude of the errors appears to be a function of the spatial resolution of the map, the original size of the land-cover classes, and the spatial patterns of the classes.
A computerised glow curve deconvolution (CGCD) analysis was applied to the main dosimetric peak of #alpha#-Al_2O_3:C in order to study the effects of light on the glow curve shape. It was shown that both the light-induced signal and the light-induced fading effects tend to shift the main dosimetric peak to higher temperatures and at the same time change its shape. Furthermore it was confirmed that the magnitude of the light-induced signal depends on radiation history and, by increasing the duration of light exposure, the magnitude of the light-induced signal reaches a plateau, thereby implying the saturation of the phototransfer process. (author).
We study heavy physics effects on the Higgs production in {gamma}{gamma} fusion using the effective Lagrangian approach. We find that the effects coming from new physics may enhance the standard model predictions for the number of events expected in the final states {bar {ital b}}{ital b}, {ital WW}, and {ital ZZ} up to one order of magnitude, whereas the corresponding number of events for the final state {bar {ital t}}{ital t} may be enhanced up to two orders of magnitude. {copyright} {ital 1996 American Institute of Physics.}
We study heavy physics effects on the Higgs production in #gamma##gamma# fusion using the effective Lagrangian approach. We find that the effects coming from new physics may enhance the standard model predictions for the number of events expected in the final states bar bb, WW, and ZZ up to one order of magnitude, whereas the corresponding number of events for the final state bar tt may be enhanced up to two orders of magnitude. copyright 1996 American Institute of Physics.
It is noted that the existence of cosmic-ray semidiurnal anisotropy of interplanetary origin has generally been attributed to the symmetrically rising density gradients perpendicular to the solar equatorial plane. An increase in the magnitude of the semidiurnal anisotropy of cosmic rays during the years 1973-1975 by a factor of 2 is in theory expected to be associated with larger magnitudes of the heliolatitudinal density gradients. The distribution of cosmic-ray intensity in the heliolatitude range + or - 7.25 deg obtained using the data of the Deep River neutron monitor is shown not to support the density gradient hypothesis. The presence of symmetrical gradients at higher heliolatitudes, however, cannot be ruled out.
This thesis deals with the evaluation of Solar Grade Silicon (SoG-Si) purified by different techniques, and also the fabrication and characterization of high efficiency and advanced bifacial solar cells. In the beginning of Chapter 1, various SoG-Si production methods relevant for this work are qualitatively described. The three feedstock materials used in this work are from the Fluidized Bed Reactor (FBR) process, metallurgical feedstock-I and feedstock-II process. In metallurgical feedstock-I, the lifetime of the minority charge carriers in multicrystalline silicon (mc-Si) samples at the grain boundaries are found to be higher than the grains themselves possibly due to lower resistivities in the grain boundaries. The efficiency of the best solar cell obtained using the mc-Si metallurgical feedstock-I is 16.1%. It has been identified that the fast light induced degradation, whose magnitude is lower than that of a reference cell suggests the formation of a B-metal ...
In accordance with the Department of Energy`s National Environmental Policy Act implementing procedures in Volume 10 of the Code of Federal Regulations, Section 1021,312, the Environmental Restoration and Waste Management Programmatic Environmental Impact Statement Implementation Plan has two primary purposes: to provide guidance for the preparation of the Programmatic Environmental Impact Statement and to record the issues resulting from the scoping and the extended public participation process. The Implementation Plan identifies and discusses the following: background of Environmental Restoration and Waste Management activities, the purpose of the Programmatic Environmental Impact Statement, and the relationship of the Programmatic Environmental Impact Statement to other Departmental initiatives (Chapter 1); need and purposes for action (Chapter 2); scoping process and results of the public ...
An experimental and computational study was undertaken to estimate the effects of pipe rupture and induced pipe whip impact on surround structures considered either as rigid or deformative such as concrete slabs. This program included sixteen tests using 3 inch schedule 80 (or 10) pipes made of carbon steel similar to A106 grade B. The study consisted of tests on rigid target and on concrete slab. The investigation of whip phase and impact phase was done separately for each test. For pipe impact on rigid targets, the impact forces are found to be directly related to the crush strength of the pipe and the general pipe deformation following the impact. For pipe impact on concrete slabs, the response of the target to the pipe impact needs to take into account the local effect such as penetration and localized damage on the slab. The test matrix ...
Performance assessments for the Area 5 Radioactive Waste Management Site on the Nevada Test Site have used three different mathematical models to estimate Rn-222 flux density. This study describes the performance, uncertainty, and sensitivity of the three models which include the U.S. Nuclear Regulatory Commission Regulatory Guide 3.64 analytical method and two numerical methods. The uncertainty of each model was determined by Monte Carlo simulation using Latin hypercube sampling. The global sensitivity was investigated using Morris one-at-time screening method, sample-based correlation and regression methods, the variance-based extended Fourier amplitude sensitivity test, and Sobol's sensitivity indices. The models were found to produce similar estimates of the mean and median flux density, but to have different uncertainties and sensitivities. When the Rn-222 effective diffusion coefficient was estimated using ...
The impact properties of high-strength low alloy TRIP steels such as 'TRIP-aided dual-phase steel' and 'TRIP-aided bainitic steel' associated with the transformation-induced plasticity (TRIP) of retained austenite were investigated for some applications to the automotive impact members. The TRIP steels possessed far higher impact absorbed value and lower ductile-brittle transition temperature than the conventional ferrite-martensite and ferrite-pearlite steels. The stress relaxation resulting from the strain-induced transformation of retained austenite islands or films improved the impact properties in terms of suppressing void and/or crack initiation and these propagation. The best impact properties were completed in the steel composing of uniform fine bainitic lath structure and a large amount of stable interlath retained austenite films. ...
This economic impact analysis (EIA) examines compliance costs and economic impacts resulting from the U.S. Environmental Protection Agency`s (EPA`s) proposed revisions to effluent limitations guidelines and standards for the Coastal Subcategory of the U.S. oil and gas industry. The EIA estimates economic impacts in terms of annualized costs; production losses; and changes in equity, working capital, and other indicators of financial health at the firm level. In addition, impacts on employment and affected communities, foreign trade, and new sources are considered. A Regulatory Flexibility Analysis detailing the impacts on small businesses within the coastal oil and gas industry also is included in the EIA.
Three complementary impact welding technologies are described in this paper. They are explosive welding, magnetic pulse welding, and laser impact welding, which have been used to provide metallurgical bonds between both similar and dissimilar metal pairs. They share the physical principle that general impact-driven welding can be carried out by oblique impact but are used at different length scales from meters to sub-millimeter. The different length scales require different kinds of systems to drive the process, and the scales themselves can give different weld morphologies. Metallographic analysis on cross-sections shows a wavy interface morphology which is likely the result of an instability associated with jetting, which scours the surfaces clean during impact. The normalized period and...
Using standard brass alloy samples, an approach to reduce the laser-induced breakdown spectroscopy measurement uncertainty was tested and proved. Two important parameters for plasma characterization, the plasma temperature and the electron density, were applied to minimize the signal uncertainties due to uncontrollable experimental parameter variations. Results show that for the pulse-to-pulse analysis, the signal fluctuations can be significantly reduced by utilizing the plasma characteristic information. The major source for the single pulse fluctuations is the redistribution of the characteristic line at different temperatures according to the Boltzmann distribution under LTE. The change of the degree of ionization also contributes to the signal fluctuations. For the multi-pulse analysis, due to the nonlinear relationship between the plasma temperature and the line intensity, it is not applicable to utilize the Boltzmann distribution to ...
To address the need for integrated models of advanced power generation systems and for improved analysis techniques, the US Department of Energy (DOE), through the Morgantown Energy Technology Center (METC), has supported the development of performance, emissions, and cost models of several advanced power generation systems, including integrated gasification combined cycle (IGCC), externally-fired combined cycle (EFCC) and pressurized fluidized bed combustion (PFBC) concepts. Simultaneously, numerical methods for simulation of uncertainties and optimization of process flowsheets have been implemented in the DOE`s public version of ASPEN. The new process models and computational capabilities have been applied to demonstrate the benefits of quantitative approaches to dealing with uncertainty and for optimizing technologies in the face of uncertainty. This paper focuses on modeling and assessment of the EFCC system concept. ...
Antideuterons are among the most promising galactic cosmic ray-related targets for dark matter indirect detection. Currently only upper limits exist on the flux, but the development of new experiments, such as GAPS and AMS-02, provides exciting perspectives for a positive measurement in the near future. In this Paper, we present a novel and updated calculation of both the secondary and primary antideuteron fluxes. We employ a two-zone diffusion model which successfully reproduces cosmic-ray nuclear data and the observed antiproton flux. We review the nuclear and astrophysical uncertainties and provide an up to date secondary (i.e. background) antideuteron flux. The primary (i.e. signal) contribution is calculated for generic WIMPs annihilating in the galactic halo: we explicitly consider and quantify the various sources of uncertainty in the theoretical evaluations. Propagation uncertainties, as is the case of antiprotons, ...
In this study, adjoint sensitivity theory is developed for equations of two-dimensional steady-state flow in a confined aquifer. Both the primary flow equation and the adjoint sensitivity equation are solved using the Galerkin finite element method. The developed computer code is used to investigate the regional flow parameters of the Leadville Formation of the Paradox Basin in Utah and the Wolcamp carbonate/sandstone aquifer of the Palo Duro Basin in the Texas Panhandle. Two performance measures are evaluated, local heads and velocity in the vicinity of potential high-level nuclear waste repositories. The results illustrate the sensitivity of calculated local heads to the boundary conditions. Local velocity-related performance measures are more sensitive to hydraulic conductivities. The uncertainty in the performance measure is a function of the parameter sensitivity, parameter variance and the correlation between parameters. Given a parameter covariance matrix, ...
A new evaluation (UKFY2) has been prepared of the independent and cumulative yields of the products of fission induced by thermal, fast, and 14 MeV neutrons in nuclides important for reactor design and operation and for fuel and waste management. Three spontaneously fissioning nuclides were also considered. The evaluation used a database that is considered to be complete up to early 1989. Careful study was made of experimental uncertainties and discrepancies, emphasizing the need for further measurements. Gaps in the data were filled by interpolation and extrapolation, using fits to empirical models. The yields were subsequently adjusted to fit physical constraints of the fissioning process. This paper describes the evaluation, which was submitted and accepted for inclusion in the JEF2 file. The file was produced in January 1990 and a revision of cumulative yield uncertainties distributed in January 1991.
A standard of "2"1"0Pb in solution was produced at the National Physical Laboratory by a novel technique combining Cerenkov counting with the established liquid scintillation efficiency tracing technique known as the CIEMAT/NIST method. Coincidence counting was applied in order to validate the measurements and the activity concentrations of the solution determined with each technique are shown to be in agreement. Radiochemical separation of the "2"1"0Pb from its daughters was also necessary and the scheme for the separation is described. After performing this two-stage standardisation, the uncertainty was successfully lowered to 0.66% (k=1). This uncertainty is approximately a factor of four lower than previously achieved at NPL by the classical method of standardisation of radionuclides, i.e. coincidence counting.
This issue has the following articles: (1) Deterrence with a Minimum Nuclear Stockpile - Commentary by Bruce T. Goodwin; (2) Enhancing Confidence in the Nation's Nuclear Stockpile - Livermore experts are participating in a national effort aimed at predicting how nuclear weapon materials and systems will likely change over time; (3) Narrowing Uncertainties - For climate modeling and many other fields, understanding uncertainty, or margin of error, is critical; (4) Insight into a Deadly Disease - Laboratory experiments reveal the pathogenesis of tularemia in host cells, bringing scientists closer to developing a vaccine for this debilitating disease. (5) Return to Rongelap - On the Rongelap Atoll, Livermore scientists are working to minimize radiological exposure for natives now living on or wishing to return to the islands.
Today?s demand on high supply chain performance requires higher awareness about supply chain risks and uncertainty. The purpose of this paper is to analyse the role of temporary storage in the transport network in a supply chain perspective. The primary research question concerns the purpose or role of temporary storage and whether management of temporary storage can contribute to reducing risks and uncertainty in the supply chain. The research is based on a system-theoretical approach, which emphasizes a holistic view instead of the characteristics of the different parts. The research method used in this paper is abductive. Existing theories are used to formulate a framework which leads to a conceptual model description of the temporary storage function. This model is then supported and v...
Over a 6.5-year period a total of 2554 values were reported by nine laboratories for 259 certified or reference nutrient concentrations in 26 certified reference materials (CRM) submitted to contract laboratories, blinded, as part of the qualifying process for analytical contracts and in the routine sample stream as part of the National Food and Nutrient Analysis Program. Each value was converted to a Z?-score, reflecting the difference from the assigned value related to the combined expected analytical uncertainty plus the uncertainty in the CRM value. Z?-scores >|3.0| were considered unacceptable. For some nutrients (Na, folate, dietary fiber, pantothenic acid, thiamin, tocopherols, carotenoids, monounsaturated, and polyunsaturated fatty acids), >20% of Z?-scores were >|3.0|. For total f...
An ytterbium-169 high dose rate brachytherapy source, distinguished by an intensity-weighted average photon energy of 92.7 keV and a 32.015#+-#0.009 day half-life, is characterized in terms of the updated AAPM Task Group Report No. 43 specifications using the MCNP5 Monte Carlo computer code. In accordance with these specifications, the investigation included Monte Carlo simulations both in water and air with the in-air photon spectrum filtered to remove low-energy photons below 10 keV. TG-43 dosimetric data including S_K, D(r,#theta#), #LAMBDA#, g_L(r), F(r,#theta#), #phi#_a_n(r), and #phi#_a_n were calculated and statistical uncertainties in these parameters were derived and calculated in the appendix.
Vacuum pressure standards of the orifice-flow type require known gas flows of 10/sup -6/ mol/s (10/sup -2/ atm cm/sup 3//s at 0 /sup 0/C) and less. Known gas flows can also be used to calibrate ''standard'' leaks by comparing the pressures generated when flows from the leak and the flowmeter are alternately passed through a constant conductance. Two constant-pressure, piston displacement flowmeters developed at the National Bureau of Standards are described that can generate flows between 10/sup -6/ and 10/sup -10/ mol/s with an estimated uncertainty of 0.8% to 2%. Comparisons of the flowmeters with alternate calibration techniques, and repeated low-range leak and vacuum gauge calibrations, have been used to confirm the estimated uncertainty and random errors of the flowmeter.
Short-duration measurements have been widely used to screen for exposures to elevated radon concentrations in individual houses or at state or regional levels. However, a number of factors, including spatial and temporal variability in radon concentrations, must be considered before comparison to concentration guidelines can be made. Daily variations in radon concentration can lead to inherent measurement uncertainties ranging from 20 to 100+ percent. Differences in radon concentration due to seasonal effects and/or sampling location are also variable, and do not appear to be regionally consistent. Winter/summer concentration ratios, for example, have been observed to vary by as much as a factor of 10 in basements and by a factor of 5 in first floors. In this paper the implications of these uncertainties on the use of short-term sampling for inferring long-term exposures are discussed.
The application of a method for determining the temperature of an oxygen-replenished air stream heated to 2600 K by a hydrogen burner is reviewed and discussed. The purpose of the measurements is to determine the spatial uniformity of the temperature in the core flow of a ramjet test facility. The technique involves sampling the product gases at the exit of the test section nozzle to infer the makeup of the reactant gases entering the burner. Knowing also the temperature of the inlet gases and assuming the flow is at chemical equilibrium, the adiabatic flame temperature is determined using an industry accepted chemical equilibrium computer code. Local temperature depressions are estimated from heat loss calculations. A description of the method, hardware and procedures is presented, along with local heat loss estimates and uncertainty assessments. The uncertainty of the method is estimated at {+-}31 K, and the spatial uniformity was measured ...
The difference between the two nonclassical lights, i.e., the squeezed state and number-phase minimum uncertainty state (NUS) is discussed. The four different generation principles for NUS are described. They are: unitary evolution using self-phase modulation; nonunitary state reduction by the first kind measurement; controlled state reduction by quantum correlation measurement-feedback, and high saturated laser oscillation with suppressed-pump-noise. The constant current-driven semiconductor laser based on the last principle generated the NUS with photon number noise reduced below the standard quantum limit by 40 percent in the entire frequency region from dc to 1.1 GHz. Several applications of NUS including quantum communication, quantum mechanical computers and interferometric gravitational detection are discussed briefly. This presentation is represented by viewgraphs only.
We have obtained radial velocities for 69 stars in the globular cluster M2 (NGC 7089). M2's rotation axis is, within sizeable uncertainties, perpendicular to the major axis determined by the flattening. The ratio of rotational to random kinetic energy agrees with that predicted from the ellipticity assuming an oblate figure and an isotropic velocity-dispersion tensor. We have fitted King-Michie models to determine M2's mass, the exponent of an assumed power-law mass function, and the anisotropy radius. The most significant sources of uncertainty in the modeling are the velocity dispersion, the distance, and the mass-luminosity relation for the cluster stars. The models favor mass functions similar to or shallower than the Salpeter initial-mass function and a moderate amount of velocity anisotropy.
We suggest a procedure for estimating uncertainties in neutron cross sections calculated with a nuclear model descriptive of a specific mass region. It applies standard error propagation techniques, using a model-parameter covariance matrix. Generally, available codes do not generate covariance information in conjunction with their fitting algorithms. Therefore, we resort to estimating a relative covariance matrix a posteriori from a statistical examination of the scatter of elemental parameter values about the regional representation. We numerically demonstrate our method by considering an optical-statistical model analysis of a body of total and elastic scattering data for the light fission-fragment mass region. In this example, strong uncertainty correlations emerge and they conspire to reduce estimated errors to some 50% of those obtained from a naive uncorrelated summation in quadrature. 37 references.
We investigate the extent to which the pure magnification effect of gravitational lensing can be extracted from galaxy clustering statistics, by a nulling method which aims to eliminate terms arising from the intrinsic clustering of galaxies. The aim is to leave statistics which are free from the uncertainties of galaxy bias. We find that nulling can be done effectively, leaving data which are relatively insensitive to uncertainties in galaxy bias and its evolution, leading to cosmological parameter estimation which is effectively unbiased. This advantage comes at the expense of increased statistical errors, which are in some cases large, but it offers a robust alternative analysis method to cosmic shear for cosmological imaging surveys designed for weak lensing studies, or to full modelling of the clustering signal including magnification effects.
In this paper, a comparison is done between two different techniques in measuring the AC voltage. The first technique is the single junction thermal voltage converters (SJTVC) which consist of one thermal element (TE) which its output e.m.f. in the range of 7-12mV and the other is the new designed thermal voltage converters which consist of a number of TEs connected in parallel, series and series/parallel to increase their output e.m.f. (becomes in the range of 35-51mV). The effect of increasing the output e.m.f. is studied in this paper through evaluating the uncertainty budget and proved that its increase has a great effect on the accuracy and the uncertainty of the AC voltage measurement.
SummaryThis paper examines the sensitivity and uncertainty of evaporation estimates from Nasser Lake, south of Egypt using data collected at the floating station Raft, 2km upstream of the Aswan High Dam, and 12 evaporation models. Based on their approach the evaporation models were ranked in five classes, respectively the Bowen ratio energy budget (BREB) approach, three energy-aerodynamic based methods, a mass transfer method, two temperature and five solar radiation-temperature approaches. State dependent parameter models were used to estimate the sensitivity indices of the different evaporation estimation methods at daily and monthly frequencies. A drastic reduction in the cost of the sensitivity analysis was obtained when coupled with efficient sampling methods, producing quasi-Monte Ca...
This paper presents a trial of probabilistic simulation for performance assessment of high-level waste (HLW) disposal using the Monte Carlo method. Based on the Reference Case conceptual model in H12, a new integrated simulation system which allowed us to rapidly evaluate the effect of data uncertainty was developed. The doses to hypothetical exposure group were compared with the results of H12 that were performed by using a point-wise approach, in terms of maximum total dose. This study showed that H12 results were consistent with results of probabilistic simulation and also showed that transmissivity had a strong influence for the uncertainty of the system performance in all simulation time. (author)
This paper presents a new mathematical model for designing distribution networks in a supply chain system considering service level constraint optimizing strategic decisions (location), tactical decisions (inventory), and assigning decisions. In real-world cases, demand, traveling time or any parameters in classical models may change over the period of time. So, considering uncertainty yields more flexibility for the results and the proposed model. In our study, environmental uncertainty is described by discrete scenarios. In this model, we have service level constraint in order to prevent inventory lost in distribution centers (DCs). Also, we assume that customer's demand is stochastic with Poisson distribution function and DCs have coverage radius constraints thus any DC cannot service a...
Objective:To evaluate the impact of avoidable mortality on the changes in life expectancy at birth in Spain.Methods:Standard life table techniques...Full Text Available
IntroductionMale sexual dysfunction is a common complication of diabetes (DM), but the relative impact of erectile dysfunction (ED), orgasmic dysfunction (OD), and/or...Full Text Available
We successfully reproduce one of the French pipe whip experiments with the computer code WIPS. The WIPS results are in excellent agreement with the experimental data and the French computer code TEDEL. This justifies the use of its pipe element in conjunction with its U-bar element in a simplified method of impact analyses.
The impact of introducing a 3,6,9-trioxadecyloxyl group at various positions of the desazadesferrithiocin (DADFT) aromatic ring on iron clearance and organ distribution is described. Three DADFT...Full Text Available
BackgroundHelminth infections can alter susceptibility to malaria. Studies need to determine whether or not deworming programs can impact on Plasmodium infections...Full Text Available
The paper presents a review of the current state of knowledge on the likely impacts of extreme weather and climate events on coastal zones and small islands in the context of climate change. Possible response options, including prevention, preparedness and adaptation, are indicated.
PURPOSE This study was designed to evaluate the impact of electronic medical record (EMR) implementation on quality of diabetes care.METHODS We conducted a 5-year longitudinal...Full Text Available
This study investigated the impact of lifelong sedentariness on skeletal muscle mass and mitochondrial function. Thirty C57BL/6 strain mice (2 months) were randomly divided into three groups (young-Y;...Full Text Available
Objectives:Despite its impact on health policy, the relationship between geographical proximity and health care seeking has received scant attention in the medical literature. This...Full Text Available
PURPOSE We wanted to assess the impact of an electronic health record–based diabetes clinical decision support system on control of hemoglobin A1c (glycated hemoglobin),...Full Text Available
A collaborative research effort by scientists in several states and in Canada has produced information to develop a formal risk assessment of the impact of Bt corn on monarch butterfly...Full Text Available
Few data exist about the impact of computerized prescribing systems on outpatient medication errors (MEs) and adverse drug events (ADEs). We compared the rates of MEs and ADEs in handwritten sites versus...Full Text Available
ObjectiveTo investigate the impact white matter hyperintensities (WMH) detected on MRI have on motor dysfunction and cognitive impairment in non-demented elderly...Full Text Available
This study explored posttraumatic growth (PTG), positive change resulting from struggling with trauma, among 7- to 10-year-olds impacted by Hurricane Katrina. Analyses focused on child self-system...Full Text Available
The report details the economic impact of two alternative regulatory options; a Treated Discharge Option and a Zero Discharge Option on facilities that would have to comply with the regulations as part of the reproposal of effluent limitations and standar...
This report estimates the economic and financial effects of compliance with the proposed effluent limitations guidelines and standards for the Centralized Waste Treatment (CWT) industry. The Environmental Protection Agency (EPA) has measured these impacts...
Objective: The aim of this study was to investigate the impact of a program of repeated assessments, feedback, and training on the quality of coded clinical data in general practice.Design:...Full Text Available
Section 204 of the Energy Independence and Security Act of 2007 (EISA 2007) requires EPA to assess and report to Congress on the impacts to date and likely future impacts of the increased use of biofuels as required by the Clean Air Act, section 211(0). Environmental issues (...
Twenty-two cases of indigestion occurred in a 650-cow herd. Five cows had severe sand abomasal impaction, diagnosed by laparotomy. The pH of prepartum cows’ urine was < 6.0 and of sand...Full Text Available
ObjectiveThere has been much debate about the value of condoms in HIV/STI programming. This should be informed by evidence about intervention impact on condom use, but there is limited...Full Text Available
The visual impact of wind turbines is one of the main factors affecting public acceptance of wind parks. This paper evaluates the visual impact of a wind park in Chania, Crete, using the Spanish method of evaluation. The outcomes are combined with the psychometric testing of the residents by the use of questionnaires and with the values of the Spanish method about various scenarios concerning the size of the wind park (double, half, one wind turbine). The results of the study prove that the quantification of the potential visual impact could minimize this, apparently, main reason that affects public acceptance. (author)
The US Department of Energy, Division of Electric Energy Systems, has undertaken to identify the environmental issues and potential impacts associated with the installation of underground electric power transmission systems. This study reports the results of investigations into the advanced cable technologies being considered for future underground applications, as part of the development oriented research program of the Division of Electric Energy Systems. While the technology involves a high level of sophistication, there are relatively few impacts to the environment that are potentially significant, and of these none are inherently non-mitigable. Route planning, system design, and methods of construction and accident response can be pursued in order to minimize impacts where strict constraints are appropriate.
This study is an evaluation of the potential environmental impacts of contaminated groundwater from the ASARCO metals refining facility adjacent to the ...
... small water or ice particles by impaction ... flight recording; principally the hydrometeor charge unit ... capability of directing aircraft movements by radio ...
This book is divided into the following chapters: the atmospheric boundary layer; atmospheric diffusion; pollutants and their properties; and environmental monitoring and impact.
digital libraries, which was identified as a national challenge in the Information ... The linkages between the many digital libraries and information services are ...
The paper discusses the potential environmental impacts associated with the operation of a large, say 350 MWe, gas-fired combined cycle power station. It concludes that if appropriate control methods are introduced at the design stage of the plant, environmental impacts are minimal and can be considered acceptable. (author).
This study provides information on energy resource development and the efforts of State and local communities in the Rocky Mountain, Appalachian, and coastal regions to deal with the related social and economic impacts. It also provides information on the range of options and resources generally available to States and local communities from local, State, industry, and Federal sources to plan for and mitigate the adverse effects of energy development. Onsite visits and interviews with State, local, and Federal officials and private industry involved in mitigating socioeconomic impacts were made.
Supplement B to the Terra Nova Development Application provides a description of the floating production storage and offloading (FPSO) vessel system selected for the development, a summary of the reasons for selecting the system, and the impact of this selection on the Development Plan, the Benefits Plan, the Environmental Impact Statement and the Socio-Economic Impact Statement. There is also a description of the contractor alliance approach to be used in the Terra Nova Development. Refs., tabs., figs.
A viscoelastically prestressed polymeric matrix composite (VPPMC) is produced by applying tension to polymeric fibres, the tensile load being released prior to moulding the fibres into a matrix. Following matrix solidification, compressive stresses imparted by the viscoelastically strained fibres improve composite tensile, flexural and impact properties. This study focuses on the potential for useful life and impact protection capability by performing Charpy impact tests on nylon 6,6 fibre-polyester resin samples subjected to accelerated ageing. Prior to testing, time-temperature superposition principles were used, the samples being aged by heating to 60degreeC for periods representing a 10-fold increase over previous work. The results demonstrated no deterioration in impact performance ov...
In order to promote environmental damage monitoring and environmental impacts assessment caused by mining in China, the most significant project that uses advanced Earth Observation technology to assess environmental impacts caused by mining, namely MINEO (assessment and monitoring the environmental impact of mining activities in Europe using advanced Earth Observation technology) was introduced and its enlightenment to China were investigated. It was proposed that an integrated technical framework of monitoring environmental impacts caused by mining be designed, quantitative inversion of biological and environmental parameters from RS data be emphasised, hyperspectral Remote Sensing be applied, RS and GIS be integrated with professional models, multi-object applications of RS be implemented, and related standards and specification be drawn up based on typical case study sites. 23 refs., 1 fig.
The purpose of the study is to analyze the economic impacts that are likely to result from promulgation of the proposed best practicable control technology (BPT), best available technology economically achievable (BAT) and Best Conventional Technology (BCT) effluent limitations and standards on placer mining in the United States. The results of the economic impact analysis will help establish pollution control regulations that are economically achievable. The analysis examines how each of four alternative pollution control technologies affects the financial viability of placer mines in the United States. The impacts examined include reduced profitability, production cutbacks, mine closures, and employment and earning losses, as well as impacts to the local economies.
L_#alpha#/L_l X-ray intensity ratios have been measured in elements Ta, W, Au, Hg, Tl, Pb, Bi, Th and U using L-shell photoionization by 60 keV photons. The present results are found to agree with the calculated values of Scofield within experimental uncertainties. (author).
Smith-Purcell (S-P) radiation is produced when electrons graze the surface of a grating. Calculations based on the theory of diffraction radiation show that, given severe restrictions on e"--beam quality, S-P radiation is highly efficient. Efficient S-P x-ray generation requires relativistic e"- beams having a transverse momentum and dimension whose product approaches the Heisenberg uncertainty limit.
This paper discusses the storage of spent nuclear fuel by countries around the world. At the present time, all countries are storing it. A small number of countries are reprocessing it for recycling. Essentially all countries are preparing for eventual disposal of end waste form. There is much uncertainty and controversy over what should and will happen.
... matrices were written in the form R(t) = R'(t) Mpp T V(t) = V (t) MppT (C-3) 49 Page 59. ... GW~/EE/64.-9 where ra(!L) rb(L) 0 MPPT= (C-4) [rb(L) ra(L) 0 ...
The concept of the modern data acquisition system and some functional specialties of the programming software--Visual Basic 6.0 are introduced. The construction and theory of the hardware and the designing principle of the software are described. Experimental results showed that the real-time data acquisition rate was as high as 10 times per second in the system. And the relative standard uncertainty of the measurement was less than 0.5%. (authors)
The objective was to find out whether international research has now provided sufficiently reliable models to assess the corrosion behavior of spent fuel in groundwater and by this to contribute to answering the question whether the highly radioactive used fuel from nuclear reactors can be disposed of safely in a geological repository. Principal project results are described in the paper
The application of various signal processing methods to extract energy storage information from plasma diamagnetism sensors occurring during physics experiments on the Tandom Mirror Experiment-Upgrade (TMX-U) is discussed. We show how these processing techniques can be used to decrease the uncertainty in the corresponding sensor measurements. The algorithms suggested are implemented using SIG, an interactive signal processing package developed at LLNL.
Based on BACODINE network notification the Whipple Observatory gamma-ray telescope has been used to search for the delayed TeV counterpart to BATSE-detected gamma-ray bursts. In the fast slew mode, any point in the sky can be reached within two minutes of the burst notification. The search strategy, necessary because of the uncertainty in burst position and limited FOV of the camera, is described.
The Subseabed Disposal Project (SDP) was part of an international program that investigated the feasibility of high-level radioactive waste disposal in the deep ocean sediments. This report briefly describes the seven-step iterative performance assessment procedures used in this study and presents representative results of the last iteration. The results of the performance are compared to interim standards developed for the SDP, to other conceptual repositories, and to related metrics. The attributes, limitations, uncertainties, and remaining tasks in the SDP feasibility phase are discussed.
The uncertainties of growth in Croatian future energy, particularly electricity demand, together with growing environmental considerations and protection constraints, are such that Croatia needs to have flexibility to respond by having the option of expanding the nuclear sector. The paper deals with nuclear energy as an option for croatian sustainable economic development. The conclusion is that there is a necessity for extended use of nuclear energy in Croatia because most certainly nuclear energy can provide energy necessary to sustain progress. (author).
A primary and basic question prevails in the methanol industry - What will be the global demand for methanol, for the expanded production of methyl tertiary butyl ether (MTBE), during the next few years This article attempts to answer the question by discussing the global market; supply and demand factors; the market in North America, Western Europe, Far East and Asia, South America, and other regions; and the uncertainties that remain.
We report an uncertainty evaluation of an optical lattice clock based on the $^1S_0\\leftrightarrow^3P_0$ transition in the bosonic isotope $^{174}$Yb by use of magnetically induced spectroscopy. The absolute frequency of the $^1S_0\\leftrightarrow^3P_0$ transition has been determined through comparisons with optical and microwave standards at NIST. The weighted mean of the evaluations is $\
Zanker has recently presented nomographs for determining particle settling velocities in solid-liquid systems. These nomographs were based on the general correlations developed by Barnea and Mizrahi and Barnea and Mednick. This work presents an equation directly computing particle settling velocities, eliminating the uncertainty associated with nomographs.
The effect of measurement geometry on the determination of the activity of solutions containing "1"2"5I for use in brachytherapy applications has been investigated for 5 mL plastic syringes and 2 mL conical glass dose vials as a function of filling mass. New dial settings for the syringes over a filling mass range of 1 to 3 g have been determined to be 497#+-#8 and 469#+-#8 (expanded, k=2, uncertainties) for the NIST Capintec CRC-12 and Capintec CRC-35R, respectively, with any effect due to the filling mass lying within the uncertainty in the activity calibration. A filling mass effect was observed in the dose vials, causing a 10.5% reduction in the chamber response from a 2 g filling mass to 1 g. Dial settings at 2 g were experimentally found to be 143#+-#2 and 135#+-#2 (expanded uncertainties) for the NIST Capintec CRC-12 and Capintec CRC-35R, respectively. The appropriate dial settings for the same vials with a 1 g ...
Since the oil prices decreased during June 2008, many uncertainties drive the energy markets. The author aims to analyze the future battles around the the dying resources, taking into account that the alternatives sources will need time to develop. The author analyzes also the relation energy and climate in the preservation of the fundamental equilibrium. (A.L.B.)
A comparison was made of the advantages and disadvantages of two codes, SAND-II and FERRET, for determining the neutron flux spectrum and uncertainty from experimental dosimeter measurements as anticipated in the FFTF Reactor Characterization Program. This comparison involved an examination of the methodology and the operational performance of each code. The merits of each code were identified with respect to theoretical basis, directness of method, solution uniqueness, subjective influences, and sensitivity to various input parameters.
In the past few months, there has been public discussion relating to a new perspective on blood safety and specifically upon measures to prevent or discourage donation by individuals with a diagnosis of myalgic encephalopathy-chronic fatigue syndrome. This reflects an intriguing interplay between science, public health and public concern and illustrates some of the difficulties of making decisions in the face of uncertainty and inadequate information.
Design-for-reliability concepts can be applied to the products of the construction industry, which includes buildings, bridges, transportation systems, dams, and other structures. The application of a systems approach to designing in reliability emphasizes the importance of incorporating uncertainty in the analyses, the benefits of optimization analyses, and the importance of integrating reliability, safety, and security. 4 refs., 3 figs.
In this paper the robust stability analysis of a single machine infinite bus system is investigated using interval matrix theory. Specifically the parameters of the power system stabilizer are considered as uncertainties in the system A matrix. The range of these parameters for which the system is Hurwitz stable is then found using interval matrix theory. (Author)
A comparison of maximum likelihood (or chi-square) and Bayesian peak fitting techniques shows that the latter can reduce peak intensity uncertainties by a factor of up to ten in the case of closely separated doublets, leading to greatly improved doublet resolution. The need for laboratories to demonstrate the reliability of their chosen peak fitting techniques and measures of peak intensity is also demonstrated. (orig.)
A comparison of maximum likelihood (or chi-square) and Bayesian peak fitting techniques shows that the latter can reduce peak intensity uncertainties by a factor of up to ten in the case of closely separated doublets, leading to greatly improved doublet resolution. The need for laboratories to demonstrate the reliability of their chosen peak fitting techniques and measures of peak intensity is also demonstrated. (orig.).
This paper mainly considers the asymptotic stability of interval neutral delay-differential systems, which corrects a technical error in the proof given in [Applied Math. Letters, 16(2003) 1063-1068] by a linear fractional transformation of an interconnection matrix with structured real parametric uncertainties. In addition, a new condition, in terms of the structured singular value, is provided to ensure the stability of the interval system. Finally, an example is given to demonstrate the validity of our criteria.
A laser spectrometer for the ethylenediaminetetra-acetic acid (EDTA) titration of magnesium or calcium ions that is designed around a handheld laser pointer as the source and a photoresistor as the detector is developed. Findings show that the use of the spectrometer reduces the degree of uncertainty and error in one part of the EDTA titrations, however overall standard deviations depend on the skill of the student and their willingness to be careful and precise.
The Integrated Status and Effectiveness Monitoring Program (ISEMP - BPA project No.2003-0017) has been created as a cost effective means of developing protocols and new technologies, novel indicators, sample designs, analytical, data management and communication tools and skills, and restoration experiments that support the development of a region-wide Research, Monitoring and Evaluation (RME) program to assess the status of anadromous salmonid populations, their tributary habitat and restoration and management actions. The most straightforward approach to developing a regional-scale monitoring and evaluation program would be to increase standardization among status and trend monitoring programs. However, the diversity of species and their habitat, as well as the overwhelming uncertainty surrounding indicators, metrics, and data interpretation methods, requires the testing of multiple approaches. Thus, the approach ISEMP has adopted is to develop a broad template ...
This paper gives a brief review about the state of knowledge on the distributional aspects of climate change impacts. The paper is largely limited to the distribution of impacts between countries (in Section 2). Although there are virtually no estimates reported in the literature, the distribution of impacts within countries is also important. Impact estimates for different sectors (agriculture, health, sea level rise) provides little guidance for estimating differential impacts within countries. It is even harder to find estimates based on social classes. The paper restricts itself to equity about the consequences of climate change. Equity issues about the consequences of emission reduction are ignored here, but should of course be part of a policy analysis. Equity issues about procedures for decision making are also ignored. The paper is organised as follows. Section 2 reviews ...
One hope to solve the cosmological constant problem is to identify a symmetry principle, based on which the cosmological constant can be reduced either to zero, or to a tiny value. Here, we note that requiring that the vacuum state is Lorentz invariant significantly reduces the theoretical value of the vacuum energy density. Hence, this also reduces the discrepancy between the observed value of the cosmological constant and its theoretical expectation, down from 123 orders of magnitude to 56 orders of magnitude. We find that, at one loop level, massless particles do not yield any contribution to the cosmological constant. Another important consequence of Lorentz symmetry is stabilization of the gravitational hierarchy: the cosmological constant (divided by Newton's constant) does not run as the quartic power of the renormalization group scale, but instead only logarithmically.
A large body of evidence indicates clear relationships between number and space processing in healthy and brain-damaged adults, as well as in children. The present paper addressed this issue regarding atypical math development. Adults with a diagnosis of dyscalculia (DYS) during childhood were compared to adults with average or high abilities in mathematics across two bisection tasks. Participants were presented with Arabic number triplets and had to judge either the number magnitude or the spatial location of the middle number relative to the two outer numbers. For the numerical judgment, adults with DYS were slower than both groups of control peers. They were also more strongly affected by the factors related to number magnitude such as the range of the triplets or the distance between t...
Summary Many important moral decisions, particularly at the policy level, require the evaluation of choices involving outcomes of variable magnitude and probability. Many economic decisions involve the same problem. It is not known whether and to what extent these structurally isomorphic decisions rely on common neural mechanisms. Subjects undergoing fMRI evaluated the moral acceptability of sacrificing a single life to save a larger group of variable size and probability of dying without action. Paralleling research on economic decision making, the ventromedial prefrontal cortex and ventral striatum were specifically sensitive to the "expected moral value" of actions, i.e., the expected number of lives lost/saved. Likewise, the right anterior insula was specifically sensitive to outcome p...
Chars prepared from potassium-exchanged carboxy methyl cellulose at several heat treatment temperatures (HTTs) were gasified in air isothermally at selected gasification temperatures (GTs) in the range 633-893 K to investigate the catalytic effectiveness of potassium species. The chars displayed a noticeable jump in gasification rate at a particular gasification temperature (called jump temperature, T{sub j}). The magnitude of jump was much less than that reported for copper and nickel catalysis, but comparable with that for calcium catalysis. Increase in HTT caused a decrease in the jump temperature of chars in contrast with the increase observed in copper, nickel and calcium catalysis; also the magnitude of jump did not decrease, but remained unaltered, on increasing HTT. The different behavior of potassium catalysis is correlated to a change in the chemical state of potassium at higher HTT. The results reveal the dependence of jump ...
A radiation hard low power, low voltage dynamic memory is obtained by the use of a dummy cell concept. Compared to conventional dummy cell concepts, this concept applies a fully sized dummy cell. By optimizing the dummy cell precharge voltage for 5 V and 3 V operation and the timing of the dummy word-line, the overall soft error rate (SER) of the chip is improved by 2 orders of magnitude. An additional improvement of 1 order of magnitude is possible for 3 V operation by adjusting substrate bias and cell plate voltage. The results are verified by an accelerated SER measurement with a radium 226 source and an additional field soft error study.
Many environmental impact statements (EIS) fail to predict environmental impacts, organize information about those impacts in a concise, logical way, and communicate that information intelligibly. This paper presents a systematic, auxiliary ''language'' for environmental analysis under the National Environmental Policy Act (NEPA), in an attempt to correct this problem. The approach improves communication among disciplinary specialists, between an interdisciplinary team and a decision-maker, and between a federal agency and the general public by helping to identify important issues and impacts, and by reducing time, effort, cost, and paperwork. The basis for the approach is found in the principal aims of the NEPA regulations and other criteria. The interdisciplinary language for environmental analysis consists of a small vocabulary, used in conjuction with a simple ...
Oil and gas resources in the offshore areas of the US constitute a significant portion of US recoverable hydrocarbon resources. The exploration, development and production of these offshore resources in California, however, could have significant air quality implications for coastal air basins. This study was developed to address a problem that frequently arises with offshore air quality assessments. Typically, such assessments are performed for a specific activity scenario (e.g., a Federal OCS Lease Sale involving a projected number of drilling rigs, platforms, pipelines, etc.) and assume a projected (but uncertain) level of recoverable oil and gas resources. This study enables interested parties to estimate air emissions and impacts for a wide range of OCS-related development scenarios. The modular emission calculation procedure and the generic impact assessment provide for maximum flexibility in reassessing the emissions and ...
The focus of this study is on the preparatory detection of uncertain net greenhouse gas (GHG) emission changes (also termed emission signals) under the Kyoto Protocol. The crucial question to be addressed is: How well do we need to know net emissions if we want to detect a specified emission signal after a given time? No restrictions exist as to what concerns the net emitter, which may be any GHG source or sink. Annex I countries are chosen as net emitters, simply for reasons of data availability and because of the excellent possibility of comparing net emitters (inter-country comparison). The countries' emissions - in an increasing number of cases even their uncertainties - are available permitting the application of preparatory signal detection techniques, which are suited to address the aforementioned question. We currently discuss four hierarchically-ordered detection concepts to assess emission signals in a preparatory manner, that is, at two ...
The influence of material configuration and impact parameters on the damage tolerance characteristics of sandwich composites comprised of carbon-epoxy woven fabric facesheets and Nomex honeycomb cores was investigated using empirically based response surfaces. A series of carefully selected tests were used to isolate the coupled influence of various combinations of the number of facesheet plies, core density, core thickness, impact energy, impactor diameter, and impact velocity on the damage formation and residual strength degradation due to normal impact. The ranges of selected material parameters were typical of those found in common aircraft applications. The diameter of the planar damage area associated with Through Transmission Ultrasonic C-scan measurements and the peak residual facesheet indentation depth were used to describe the extent of internal and detectable surface damage, respectively. ...
Previous investigations have shown promising results in using the directional cross-correlation method to estimate velocity vectors. The velocity vector estimate provides information on both velocity direction and magnitude. The direction is estimated by beamforming signals along directions in the range $[0^{\\circ}; 180^{\\circ}[$ and identifying the direction that produces the largest correlation across emissions. An estimate of the velocity magnitude is obtained from the spatial shift between signals beamformed along the estimated direction. This paper expands these investigations to include estimations of the vector velocities of a larger region by combining the estimations along several scan lines. In combination with a B-mode image, the vector velocities are displayed as an image of the investigated region with a color indicating the magnitude, and arrows showing the direction of the flow. Using the RASMUS ...
New non-collinear schemes are suggested for transverse velocity modulation of electron beams and for the generation of coherent spontaneous radiation by these transversely modulated beams. It is shown that due to the non-collinearity some orders of magnitude enhancement can be achieved for the coherent spontaneous radiation (CSR) power at both the fundamental and harmonic frequencies.
A Bianchi type-IX cosmological model has been found as a solution of Einstien's vacuum field equations with a cosmological constant. The solution represents a rotating generalziation fo the de Sitter universe. This universe shows a transition to exponential expansion and the vorticity begins to decay exponentially at the grand-unified-theory time. The point of time for this transition is independent of the magnitude of the vorticity. During the Guth inflationary era the vorticity decays by a factor of the order 10 US.
A Bianchi type-IX cosmological model has been found as a solution of Einstien's vacuum field equations with a cosmological constant. The solution represents a rotating generalziation fo the de Sitter universe. This universe shows a transition to exponential expansion and the vorticity begins to decay exponentially at the grand-unified-theory time. The point of time for this transition is independent of the magnitude of the vorticity. During the Guth inflationary era the vorticity decays by a factor of the order 10"-"1"4"2.
Based on a mathematical simulation which reproduces accurate split and velocity profiles for the 100 and 200 metre sprints, the magnitudes of altitude and mixed wind/altitude-assisted performances as compared to their sea-level equivalents are presented. It is shown that altitude-assisted times for the 200 metre are significantly higher than for the 100 metre, suggesting that the ``legality'' of such marks perhaps be reconsidered.
Sixteen spectra of the symbiotic star BF Cygni covering the period 1965-- 1970 were investigated. Variations of the line intensities, the Balmer decrements, the color, and electronic temperatures are given. Approximate values of the electron density were deduced in order to derive an order of magnitude for the sizes of the emitting regions of BF Cygni. A crude stratification and evolution model is proposed. (auth)
Apr 16, 2007 ... with a 1-sigma error radius of about 0.5 arc sec. ... It was consistent with a single point source at: RA (J2000) = 03h 13m 57.6s ... At 13000 sec. after the trigger, the magnitude in the UVOT B filter was ~19.9 with a ...
Transverse form factors have been extracted for the low-lying neutron hole (particle) states of /sup 207/Pb from inelastic-electron-scattering data. A systematic, multipolarity-and momentum-transfer-independent quenching of approx.55% in the transverse amplitude is observed when compared with single particle predictions for both electric and magnetic transitions. The magnitude of the observed effect is not readily explained by our present theoretical understanding of this nucleus.
A network of second-generation low-temperature gravitational radiation detectors is nearing completion. These detectors, sensitive to mechanical strains of order 10"-"1"8, are possible because of a variety of technical innovations that have been made in cryogenics, low-noise superconducting instrumentation, and vibration isolation techniques. Another five orders of magnitude improvement in energy sensitivity of resonant-mass detectors is possible before the linear amplifier quantum limit is encountered. 33 references, 3 figures, 1 table.
The radiation dose to a series of adult and paediatric patients undergoing cardiac catheterisations and adults having percutaneous transluminal coronary angioplasty has been measured/determined directly using lithium fluoride thermoluminescent dosemeters and indirectly using an air ionisation chamber which indicated exposure-area product. Somatic and genetic risks are estimated from the dosimetry results. It is suggested that the magnitude of the radiation hazard is negligible compared with other clinical hazards associated with these procedures. (author).
For a system of noninteracting electrons scattered by resonant levels of neutral impurities, we show that virial and quasiparticle corrections have nearly equal magnitudes. We propose a modification of the Boltzmann equation that includes quasiparticle and virial corrections and discuss their interplay on a dielectric function. copyright 1997 The American Physical Society.
Measurement results are interpreted as (sets of) values attributed to measurands, i.e., quantities (intended to be measured), i.e., properties (having a magnitude that can be expressed as a number and a reference). This relatively simple conceptual structure hides some important issues for measurement science, that the lecture will tentatively explore with a systematic reference to the International vocabulary of metrology - Basic and general concepts and associated terms (VIM) and its possible future developments.
High energy muon colliders, such as the TeV-scale conceptual designs now being considered, are found to produce enough high energy neutrinos to constitute a potentially serious off-site radiation hazard in the neighbourhood of the accelerator site. A general characterization of this radiation hazard is given, followed by an order-of-magnitude calculation for the off-site annual radiation dose and a discussion of accelerator design and site selection strategies to minimize the radiation hazard.
A general analysis is presented of a photon storage cavity, coupled to free-electron laser (FEL) cavity. It is shown that if the coupling between the FEL cavity and the storage cavity is unidirectional (for example, a ring resonator storage cavity) then storage is possible, but that if the coupling is bi-directional then storage is not possible. Parameters are presented for an infra-red FEL storage cavity giving an order of magnitude increase in the instantaneous photon power within the storage cavity. 4 refs., 3 figs.
Using spectral hole-burning-based ultraslow group velocity in a dilute solid medium, we report enhanced photon echo efficiency three orders of magnitude higher than that in a nonslow light regime. The enhancement is due to exponentially increased absorption of an optical data pulse owing to the enhanced photon-atom interaction in an ultraslow light regime, whereas echo reabsorption is negligibly small due to group-velocity dependent population depletion.
This work presents and describes the natural radioactive occurrence in oil facilities. The origins of the detected radioactivity and the reasons of its settlement are discussed. The measurements results carried out in oil facilities in the Neuquina basin (Argentine) are shown in this work. The aim is to describe the actual situation and to evaluate the magnitude of the problem. Finally, recommendations are proposed to protect the health of the workers, especially of those who carry out the cleaning of the equipment, and to guarantee an appropriate final disposal for the generated radioactive residuals. (author)
The coupling between cerebral metabolic rate of oxygen (CMRO2) and blood flow (CBF) in response to visual stimulation was evaluated by means of a model of oxygen delivery. The model predicted a nonlinear relationship between stimulus-evoked changes of oxygen consumption and blood flow. The magnitude of the CMRO2/CBF ratio index (IO2) was used to indicate the degree of flow-metabolism coupling prevailing in specific areas of the brain during physiological stimulation. Therefore, the index provided a measure of the blood oxygenation level dependent (BOLD) magnetic resonance contrast. To evaluate the changes of IO2 in response to visual stimulation, the model was applied to the effect of a changing flicker rate of a visual stimulus on the magnitudes of CBF, CMRO2, and oxygen diffusion capacity, in the human brain. Positron emission tomography (PET) was used to measure the CBF and the CMRO2 in 12 healthy volunteers who viewed a cross-hair ...
A number of interactions between magnetic fields and matter is reviewed. The resulting forces range in magnitude from the very large, obtained in high-energy fields, to the weak ones caused by the magnetostriction of ferromagnets. The fundamentals of these interactions are highlighted, and the examples discussed are forces on dipoles, particle alignment, magnetostrictive forces, magnetic forming, magnetic stirring, levitation melting, and magnetic pulsing of tool steels. (orig.)
In this work, energy-based features for gear fault diagnosis and prediction are proposed. The instantaneous energy density is shown to obtain high values when defected teeth are engaged. Three methods are compared in terms of sensitivity, reliability and computation effectiveness. The Wigner Ville distribution is contrasted to the wavelet transform and the newly proposed empirical mode decomposition scheme. It is shown that all three methods are capable of a reliable prediction. An empirical law, which relates the energy content to the crack magnitude is established.
Results are described of the study of the analytical applicability of a highly efficient ion source developed for a mass spectrometer. Its ionizer is in the form of a partially closed cavity with a small aperture for leading out ions, heated to a high temperature. The new ion source increases the sensitivity of the apparatus in operations with transuranium elements by almost two orders of magnitude. It is possible to perform isotopic analyses with a high salt content in the sample, and to study the characteristics of nuclear fuel, even without chemical separation of the sample elements.
DescriptionPhytoplankton is the collective name given to the microscopic floating plants in seas and lakes. Under certain conditions, the abundance of phytoplankton as a whole or of one or more species in particular, can reach a magnitude at which it is visible through discolouration of the sea. Some of these blooms because of the colour of the water have been called 'Red Tides'. Blooms of some 300 species of the phytoplankton are known as Harmful Algal Bloom (HAB) species in recognition of their poten [continued...
This document describes a simple and general way to generate House Simulation Protocol (HSP)-consistent internal sensible and latent loads in unoccupied homes. It is newly updated based on recent experience, and provides instructions on how to calculate and set up the operational profiles in unoccupied homes. The document is split into two sections: how to calculate the internal load magnitude and schedule, and then what tools and methods should be used to generate those internal loads to achieve research goals.
Predictions and measurements of a multimode waveguide interferometer operating in a fibre coupled, ``dual-mode'' regime are reported. With a 1.32 micrometer source, a complete switching cycle of the output beam is produced by a 10.0 nanometer incremental change in the 8.0 micrometer width of the hollow planar mirror waveguide. This equates to a fringe spacing of $\\sim\\lambda /130$. This is an order of magnitude smaller than previously reported results for this form of interferometer.
FastBit is a software package designed to meet the searching and filtering needs of data intensive sciences. In these applications, scientists are trying to find nuggets of information from petabytes of raw data. FastBit has been demonstrated to be an order of magnitude faster than comparable technologies. In this brief report, we highlight how we work with a visualization team, a network security team and a DNA sequencing center to find the nuggets in their data.
The results of research on the evaluation of the half-bead weld repair method for use on nuclear reactor components are reviewed from data obtained on thick-section test pieces and intermediate-size pressure vessels. Material properties, the magnitude of residual stresses and the structural behavior of flawed pressure vessels are being obtained to determine the adequacy of the weld repair method for application in thick-section components.
BackgroundTroponin is the preferred biomarker for risk stratification in non-ST-elevation ACS. The incremental prognostic utility of the initial magnitude of troponin...Full Text Available
Interaction of drilling fluids with a geothermal reservoir formation can result in significant permeability impairment and therefore reduced well productivity. This interaction is studied under simulated in situ geothermal conditions of overburden stress, pore fluid pressure, temperature, and pore fluid chemistry. Permeability impairment of an East Mesa KGRA reservoir material is evaluated as a function of stagnation time, drilling fluid, and temperature. Results indicate that all of these parameters contribute significantly to the magnitude and the reversibility of the impairment.
The K"+- and K"-meson cumulative production cross sections are measured at 119"0 in the laboratory system on nuclei Be, Al, Cu and Ta bombarded by 10 GeV protons. Spectra of the K"-mesons consisting of only sea quarks show universal features characteristic of the spectra of cumulative particles, which contain valence quarks. Evidence is obtained for the fact that the energy density in a flucton can exceed the mean nuclear density by an order of magnitude.
Polyacrylonitrile films have been spin cast and pyrolyzed to produce thin (500--1500 A) carbon films. These films have higher electrical conductivities than films produced by other methods at similar temperatures. The conductivity can be varied by at least four orders of magnitude by changing the pyrolysis temperature. Ultraviolet, infrared, and Raman spectroscopies were used to investigate the chemical structure of the films during different stages of processing.
Helical tomotherapy presented many unique dosimetric challenges and solutions during the initial commissioning process, and some of them are presented. The dose calculation algorithm is convolution/superposition based. This requires that the energy fluence spectrum and magnitude be quantified. The methodology for doing so is described. Aspects of the energy fluence characterization that are unique to tomotherapy are highlighted. Many beam characteristics can be measured automatically by an included megavoltage computed tomography imaging system. This greatly improves data collection efficiency.
The recently observed phenomenon of boron uphill diffusion during low-temperature annealing of ultrashallow ion-implanted junctions in silicon has been investigated. It is shown that the effect is enhanced by preamorphization, and that an increase in the depth of the preamorphized layer reduces uphill diffusion in the high-concentration portion of boron profile, while increasing transient enhanced diffusion in the tail. The data demonstrate that the magnitude of the uphill diffusion effect is determined by the proximity of boron and implant damage to the silicon surface.
Sputter-removal rates of overlayer and interfacial species on silicon are analyzed to determine sputtering yields for the species involved. Sputtering yields up to two orders of magnitude lower than those measured for silicon are found, and the results are interpreted in terms of a cascade mixing process which continually reburies much of the overlayer material beyond the escape depth of the sputtered atoms.
Sputter-removal rates of overlayer and interfacial species on silicon are analyzed to determine sputtering yields for the species involved. Sputtering yields up to two orders of magnitude lower than those measured for silicon are found, and the results are interpreted in terms of a cascade mixing process which continually reburies much of the overlayer material beyond the escape depth of the sputtered atoms.
In this brief article I review the history of astronomical photometry, touching on observations made by the ancient Chinese, Hipparchus and Ptolemy, the development of the concept (and definition) of magnitude, the endeavors of Argelander and Zoellner, work at Harvard at the end of the 19th century, and the development of photography, photomultipliers, and CCD's and their application to astronomy.
EPRI has sponsored an experimental program in the pipe whip impact and pipe rupture and depressurization areas. Sixteen pipe whip tests were performed with 3 in Schedule 80 (or 10) carbon steel pipes impacting on rigid target or concrete slab. The major testing parameters include distance, impact location, pipe rupture location, and concrete slab thickness and strength. The piping crushing at impact correlates with impact force and target response behavior. Conservatism was established by comparing measured and calculated impact forces. The pipe rupture and depressurization tests were carried out using 6 in stainless steel and carbon steel pipes under either PWR or BWR fluid conditions. These tests are of axial crack with initial machined-in surface flaw. It was found that pipe rupture would occur only if a long unstable through-wall crack was embedded in a ...
The current situation in the development of nuclear power in the world and in Czechoslovakia is briefly outlined and the possibilities are discussed of alternative energy resources. The environmental impact is described of conventional power plants firing coal; sulphur and nitrogen oxides are mentioned and their environmental impacts shown. Their quantities and the quantities of other gaseous, liquid and soid wastes produced by coal power plants are given. Annual estimates are presented of radioactive material emissions; trace amount emissions of toxic metals and their ecological risks are shown. Concern over the increasing concentration of CO_2 in the atmosphere is voiced. For nuclear power plants, the amount of radionuclides in stack emission and of those released into water flows is tabulated. Their effect on the aqueous ecosystem is characterized as is thermal pollution of water flows and the environmental impact of ...
The Loose Parts Monitoring System (LPMS) provides information on the location of a loosened or detached metal impacted onto the inner surface of a primary pressure boundary and on a mass or energy of the impact signal. For the conventional system, it is popular to employ the group delay among the sensors installed within 3 ft range from the impact source in a collection zone as stated in the Reg. Guide 1.133. However, there exist inherent errors for the estimation of the true location of the impact since it is highly dependent on the plant personnel's decision to determine the arrival time differences of the generated wave group among the neighbouring sensors. To overcome this problem in this study, the two-dimensional approach has been proposed and applied to effectively estimate the arrival time differences of the impact signal by using continuous wavelet transform which is one of ...
A new package for the air transport of hazardous materials is currently being developed in the Transportation Systems Department at Sandia National Laboratories. The baseline design has a unique impact limiter which uses layers of aluminum screen wire and aramid cloth fabric. A primary motivation for selecting this unusual combination of materials is the need for the impact limiter to not only limit the amount of load transmitted to the primary container but also remain in place during impact events so that it provides a thermal barrier during a subsequent fire. A series of uniaxial and confined compression tests indicated that the layered material does not behave like other well characterized materials. No existing constitutive models were able to satisfactorily capture the behavior of the layered material; thus, a new plasticity model was developed. The new material model was then used to characterize the response of air ...
The wastes management policy takes into account more and more often the environmental impacts mastership. This evolution is particularly appreciable when the wastes directly interact with the environment: storage, utilization for roads construction and so on. In this context the ADEME organized the 8 june 2000 a colloquium to present the new evaluation methods and tools, to describe the regulations and to identify the research programs needed for this environmental policy. Eleven papers are presented. (A.L.B.)
Major factors that contribute to maximized impact resistance of semicrystalline engineering polymers include increased matrix molecular weight, minimal rubber glass-transition temperature, and optimal rubber-particle size, which depends on matrix type. Additional constraints are posed by the limitations of available materials and commercial requirements. Expanding the understanding of impact-modified crystalline engineering polymers will further extend their property ranges and utility. This chapter describes the phenomenology of certain factors, illustrates a new technique to measure rubber particle size, and contrasts the fracture mechanisms of poly(butylene terephthalate), nylon 66, and polyacetal. 49 refs., 24 figs.
This paper describes examples of the damage resulting from the impact of a whipping pipe on a nearby pressurised pipe. The work is a by-product of a study of the motion of a whipping pipe. The tests were conducted with small-diameter pipes mounted in rigid supports and hence the results are not directly applicable to large-scale plant applications where flexible support mountings are employed. The results illustrate the influence of whipping pipe energy, impact position and support type on the damage sustained by the target pipe.
This paper describes examples of the damage resulting from the impact of a whipping pipe on a nearby pressurised pipe. The work is a by-product of a study of the motion of a whipping pipe. The tests were conducted with small-diameter pipes mounted in rigid supports and hence the results are not directly applicable to large-scale plant applications where flexible support mountings are employed. The results illustrate the influence of whipping pipe energy, impact position and support type on the damage sustained by the target pipe. (author).
Analytical models for predicting the deformation and failure of composite sandwich panels subjected to blast and projectile impact loading are presented in this paper. The analytical predictions of the transient deformations and damage initiation in the composite sandwich panels were compared with finite element solutions using ABAQUS Explicit. For the blast model, the predicted transient deformation of the sandwich panel was within 7%of FEA results, while the predicted damage initiation using Hashin's composite failure criteria was about 15%higher than FEA results in most cases. For the high velocity impact model, the predicted transient deformations were within 20%of FEA results.
Studied are the mechanical properties of welded joints and heat affected zones of the Kh8N10T steel and OT4 and VT1-2 titanium alloys on welding in Ar+deltaF_6 and Ar+CCl_2F_2 mixtures contributed to a decrease of porosity. Tensile and impact tests of welded joints have revealed that additions of sulfur hexafluoride into argon causes a decrease of impact strength in titanium alloy when the tensile strength does not depend on the composition of a halogen-containing atmosphere. Freon (CCl_2F_2) additions decrease only slightly the impact strength of the investigated alloys.
Malnutrition?in the form of insufficient energy intakes?affects millions of people worldwide and the negative impact of this kind of hunger is well acknowledged, not least by agronomists trying to increase yields to ensure a sufficient supply of food. This review focuses on another, more particular and ?hidden? form of malnutrition, namely mineral malnutrition. It illustrates the burden of disease that is caused by mineral deficiencies and the social and economic consequences they bring about. Mineral malnutrition has a considerable negative impact on individual well-being, social welfare and economic productivity. Agricultural scientists should keep the nutritional qualities of food in mind and?next to optimizing the agricultural properties of crops that are paramount for their adoption b...
... Title : The Numerical Weather Prediction System at the Italian Air Force Weather Service: Impact of Non-Conventional Observations and Increased ...
This Final Environmental Impact Statement and Environmental Impact Report (Final EIS/EIR) has been prepared to meet the requirements of the National Environmental Policy Act (NEPA) and the California Environmental Quality Act (CEQA). The Proposed Action includes the construction, operation, and decommissioning of a 48 megawatt (gross) geothermal power plant with ancillary facilities (10-12 production well pads and 3-5 injection well pads, production and injection pipelines), access roads, and a 230-kilovolt (kV) transmission line in the Modoc National Forest in Siskiyou County, California. Alternative locations for the power plant site within a reasonable distance of the middle of the wellfield were determined to be technically feasible. Three power plant site alternatives are evaluated in the Final EIS/EIR.
... Air Station, Oahu, Kahuku Training Area ... K-Pier, Hawaii, Bradshaw Army Airfield, Hawaii (R&S ... impact area); Makua Military Reservation, Oahu (R&S ...
High energy consumption and the world population increase will lead to a shrinking use of fossil fuels. The combustion of Fossil fuel leads to the increase of carbon dioxide concentration in the atmosphere which leads to the probable increase of global warming. Therefore, concerns about carbon dioxide emissions may discourage widespread dependence on fossil fuels and encourage the development and use of renewable energy systems employing a variety of technologies Renewable energy systems have themselves an environmental impact. Land use and material employed are two areas that may have an adverse impact to the positive environmental picture of the renewable energy systems. The objective of this paper is to analyze these impacts with the use of a very powerful tool, the Life Cycle Assessment. (author)
The radiation polymerization of multifunctional unsaturated polyester-monomer mixtures in wood forms interpenetrating network system. The mechanical resistance (compression, abrasion, hardness, etc.) of these composite materials are generally well over the original wood, however the impact strength is almost the same or even reduced, in comparison to the wood itself. An attempt is made using elastic polyester resins to produced wood-polyester composite materials with improved modulus of elasticity and impact properties. For the impregnation of European beech wood two types of elastic unsaturated polyester resins were used. The exothermic effect of radiation copolymerization of these resins in wood has been measured and the dose rate effects as well as hardening dose was determined. Felxural strength and impact properties were examined. Elastic unsaturated polyester resins improved the impact strength of ...
Dynamic pipe impact tests were performed in order to determine the impact conditions for which a 2 inch Schedule 80 carbon steel target pipe would not be broken if it were impacted during a pipe whip event created by a postulated break of an adjacent larger parallel pipe. Such pipe/pipe impact scenarios are of special interest for the feeder pipes of a CANDU reactor because the large number of closely spaced parallel feeder pipes that carry coolant between large primary system pipes and individual fuel channels in the reactor core makes it impractical to consider providing feeder pipe whip restraints. The testing which was performed involved simulating the behaviour of 3 inch and larger whipping pipes in order to study their impact with 2 inch target pipes pressurized at about 9 MPa with water at a temperature of about 290"0C. In a conservative simulation of the worst pipe/pipe ...
BackgroundMedication errors are common among inpatients and many are preventable with computerized prescribing. Relatively little is known about outpatient prescribing errors or...Full Text Available
The purpose of this study is to explain the unplanned longitudinal dose modulations that appear in helical tomotherapy (HT) dose distributions in the presence of irregular patient breathing....Full Text Available
Background, Aim, and Scope The identification and assessment of environmental tradeoffs is a strongpoint of life cycle assessment (LCA). A tradeoff made in many product systems is the exchange of potential for occupational accidents with the additional use of energy and materials. Net benefits of safety measures with respect to human health are best illustrated if the consequences avoided and health impacts induced by additional emissions are assessed using commensurable metrics. Our aim is to develop a human health impact indicator for offshore crane lifts. Crane lifts are a major cause of accidents on offshore oil and gas (O & G) rigs, and health impacts from crane lift accidents should be included in comparative LCA of O & G technologies if the alternatives differ in the use of crane li...
This paper describes a nonlinear dynamic analysis of TVA high energy line pipe whip tests using the ABAQUS-EPGEN code. The analysis considers the effects of large deformation and strain rate on resisting moment and energy absorption capability. The numerical results of impact forces, impact velocities, pipe strains, and reaction forces at pipe supports are compared to the TVA test data. The calculated pipe whip impact time and forces are also compared with those predicted using current industry practice. The calculated pipe support reaction forces are found to be in good agreement with the TVA test data except for some peak values at the very beginning of the pipe break. These peaks are believed to be due to stress wave propagation which cannot be addressed by the ABAQUS code. Both elbow crushing and strain rate have been approximately simulated. The effects are found to be important for pipe whip ...
The battery manufacturing industry has not been immune to the impact of new technologies. How one company is adapting production techniques to meet the demand for better products is discussed.
Like few other organs, the skin is continuously exposed to multiple exogenous and endogenous stressors. Superimposed on this is the impact of psychological stress on skin physiology and pathology....Full Text Available
BackgroundThe ongoing epidemiological transition in Mexico minimizes the relative impact of neurocysticercosis (NC) on public health. However, hard data on the disease frequency...Full Text Available
To meet BPA`s contractual obligation to supply electrical power to its customers, BPA proposes to acquire power generated by Klickitat Cogeneration Project. BPA has prepared an environmental assessment evaluating the proposed project. Based on the EA analysis, BPA`s proposed action is not a major Federal action significantly affecting the quality of the human environment within the meaning of the National Environmental Policy Act of 1969 for the following reasons: (1)it will not have a significant impact land use, upland vegetation, wetlands, water quality, geology, soils, public health and safety, visual quality, historical and cultural resources, recreation and socioeconomics, and (2) impacts to fisheries, wildlife resources, air quality, and noise will be temporary, minor, or sufficiently offset by mitigation. Therefore, the preparation of an environmental impact statement is not required and BPA is issuing this FONSI ...
Amotivation is a telling hallmark of negative symptomatology in schizophrenia, and it impacts nearly every facet of behavior, including inclination to attempt the difficult cognitive tasks involved...Full Text Available
Magnetic pulse welding is a solid state impact welding process, similar to explosive welding, which produces metallurgical bond by oblique high-speed impact between two metal bodies. This violent impact removes the metal surface oxide layers and then joins the two atomic level clean metal surfaces together by the incidental compression pressure. The impact velocity is at 200?400?m/s and the being welded metal surface undergoes severe plastic deformation with strain rate in the order of 106?107?s?1. The ultrafine-grained structure was observed on the welded interface. This article studied two types of similar material lap joint interfaces and the base metals were aluminum alloy 6061 and copper alloy 110. Nano-indentation testing shows that the welded interfaces have significantly greater ha...
Description: Hurricane Hugo, which struck South Carolina in September of 1989, destroyed a significant proportion of the State's timber. Primary wood-products ...
Objective:To evaluate the effect of urethral reconstructive surgery on sexual drive, erectile function and ejaculation.Materials and Methods:The...Full Text Available
Jan 31, 2006 ... Sick leave accrues at the rate of 1 hour for each 20 hour in a pay status. ... FERS: All periods of service are used in determining the FERS ...
BackgroundFloating knee injuries are usually associated with other significant injuries. Do these injuries have implications on the management of the floating knee and the final...Full Text Available
Background An increasing number of people have access to the Internet, and more people are seeking tobacco cessation resources online every year. Despite the...Full Text Available
... Zinn, J., Hoerlin, H., and Petschek, AG, "The Motion of Bomb Debris Follow- ing the Starfish Test," Radiation Trapped in the Earth's Magnetic Field ...
Our global impact is finally receiving the scientific attention it deserves. The outcome will largely determine the future course of evolution. Human-modified ecosystems are shaped by our activities...Full Text Available
... This Level 2 analysis will be somewhat less detailed, but experience in other fields including pipe whip 4 , locomotive dynamics, and nuclear fuel ...
Mechanical properties, flow characteristics and chemical resistance of polycarbonate (PC)/polybutylene terephthalate (PBT)/impact modifier (IM) blends were investigated over the various composition ranges of PC and PBT. Mechanical properties of the PC/PBT/IM blends for different IMs, butadiene based IM and butyl acrylate based IM, were studies for various compositions of the IMs. Impact strength at low temperature was also observed. For the study of chemical resistance of the PC/PBT/IM blends, the blends were dipped in organic solvent, thinner, and then variations of mechanical properties were analyzed. Tensile and flexural strengths were increased linearly and heat distortion temperature (HDT) also increased as PC content in the blends increased. Impact strength increased drastically as PC content increased up to 50 wt% and stayed stable value. Flowability decreased as PC content increased. impact ...
hlgh fiber content composites met the minlmum requirements. (1400 O F ) , the hlgher fiber content as-fabricated composites have impact strengths distinctly ...
The impacts of federal projects on wetlands should be included in documents prepared to comply with the National Environmental Policy Act (NEPA). NEPA assessments of impacts on wetlands are often related to requirements of other laws, regulations, and executive orders, such as permitting requirements under Section 404 of the Clean Water Act and those contained in Executive Order 11990, Protection of Wetlands. This paper reviews recent NEPA environmental impact statements that contained assessments of impacts on wetlands or that involved projects likely to affect wetlands. It covers documents prepared by several federal agencies, including the Army Corps of Engineers, Department of Energy, Federal Highway Administration, Soil Conservation Service, and Tennessee Valley Authority. The extent and depth of analyses of wetlands issues was found to be highly variable, both within and among agencies. Most ...
An Environmental Impact Assessment (EIA) study for any project is a time- consuming process because it has a large number of dependent and independent variables that must be taken into account. Although EIAs are dependent on geo-spatial information in order to make an assessment, there are no standard rules for conducting an environmental assessment. In addition, each assessment objective is case-dependent, based on what information is available. This paper presents a new framework for the analysis phase of the Environmental Impact Assessment (EIA) for projects, based on the integration between remote sensing technology, geographic information systems, and spatial modeling. The framework comprehensively analyzes the environmental vulnerability around the project areas and its impact on the...
... Abstract : The United States Air Force (USAF) currently operates the Milstar satellite system to provide Military Satellite Communication Systems ...
Report) A Screening Assessment of the Potential Impacts of Climate Change on Combined Sewer Overflow (CSO) Mitigation in the Great Lakes and New England Regions (Final Report)...
In the WWER-440 reactor the primary piping consists of six horizontal loops going radially from the pressure vessel, each loop having a horizontal steam generator. In this reactor type the relatively long primary piping with many curved sections requires special attention in order to successfully eliminate the consequences of the design basis accident. Emergency supports are located in appropriate places to restrict the movements of the pipe. Under normal conditions there is a gap of some centimeters between the pipe and a support so that in the pipe can be deformed freely under changing loads. This paper deals with those energy-absorbing structures used at the Loviisa Nuclear Power Plant for protection against impact loading. Places and circumstances where energy-absorbing structures are employed are specified. Development and design of impact absorber elements are discussed and impact tests are described. (Auth.).
The nucleation of microdamage under dynamic loading was investigated through planar impact experiments accomplished with a light gas gun. The microscopic observation of recovered and sectioned specimens showed that microcracks were nucleated only by cracking of brittle particles inside material. However, for comparison the in situ static tensile tests on the same material conducted with a scanning electron microscope showed that the microcracks were nucleated by many forms those were fracture of ductile matrix, debonding particles from matrix and cracking of brittle particles. The quantitative metallographic observations of the specimens subjected to impact loading showed that most of the cracked particles were situated on grain boundaries of the aluminum matrix. These facts suggested the concept of critical size and incubation time of submicroscopic cavities in the dynamic case and the mechanism of embryo-damage induced nucleation by fracture ...
The report identifies and analyzes the economic impacts of water pollution control regulations on the battery manufacturing industry. These regulations include effluent limitations and standards based on BPT (best practical control technology currently available), BAT (best available technology economically achievable), PSES (pretreatment standards existing sources), NSPS (new source performance standards), and PSNS (pretreatment standards new sources), that have been promulgated under authority of Sections 301, 304, 306, 307, 308, and 501 of the Federal Water Pollution Control Act, as Amended (the Clean Water Act). The primary economic impact variables of interest include price changes, plant closures, substitution effects, changes in employment, shifts in the balance of foreign trade, changes in industry profitability, structure, and competition, and impacts on small business.
PurposeTo determine the dosimetric impact of inter-fraction anatomical movements in prostate cancer patients receiving proton therapy.Full Text Available
SUMMARYIncreasingly multiple outcomes are collected in order to characterize treatment effectiveness or to evaluate the impact of large policy initiatives. Often the multiple...Full Text Available
ObjectiveTo describe the prevalence, intensity, and functional impact of the following types of pain associated with upper-limb loss: phantom limb, residual limb,...Full Text Available
Cancer, by definition, is a proliferative disease. The fundamental scientific issue explored at the international symposium "Cell Proliferation and Chemical Carcinogenesis" was the impact of chemically...Full Text Available
In the analysis of power systems security, recently a new concern related to possible malicious attacks caught much attention. Coordination among different transmission system operators (TSO) in an interconnected power system to counteract such attacks has become an important problem. This paper presents a general framework for describing the physical, cyber and decision-making aspects of the problem and their interrelations; within this framework, an analytic tool for the assessment of information impacts in handling on-line security after a malicious attack is proposed and discussed. The model is based on the socially rational multi-agent systems and the equilibrium of a fictitious play is considered to analyze the impacts of various levels of information available to the interconnected system operators on the outcomes of the decision-making process under attack. A 34-buses test system, with 3 systems interconnected by tie-lines, is presented ...
Snakebite envenomation is an uncommon condition in the northern hemisphere, but requires high vigilance with regard to both the systemic effects of the venom and the locoregional impact on the soft...Full Text Available
A series of OSL properties of fragments from split feldspar grains have been investigated. These are (1) the response to a radiation dose, (2) the recycling of corrected induced luminescence (L{sub i}/T{sub i}), (3) the corrected natural luminescence (L{sub N}/T{sub N}), (4) the corrected thermal transfer luminescence (termed herein L{sub tt}/T{sub tt}) and, (5) the rate of anomalous fading ('g'). It was found that the parameters of different parts of the same grain are the same. The relative uncertainty, at the 2 sigma level, at which we can claim that the measured parameters are correlated, is generally less than 5% but is ca 40% for the anomalous fading rate due to measurement uncertainty. For young partially bleached sediments, the result is that one could use one fragment to evaluate the equivalent dose and another to assess the contribution of thermal transfer resulting from preheating the natural luminescence.
The detector for retrospective radon exposure measurements is developed. The detector consists of the multilayer package of solid-state nuclear track detectors LR-115 type. Nitrocellulose films works both as {alpha}-particle detector and as absorber decreasing the energy of {alpha}-particles. The uncertainties of implanted {sup 210}Pb measurements by two- and three-layer detectors are assessed in dependence on surface {sup 210}Po activity and gross background activity of the glass. The generalized compartment behavior model of radon decay products in the room atmosphere was developed and verified. It is shown that the most influencing parameters on the value of conversion coefficient from {sup 210}Po surface activity to average radon concentration are aerosol particles concentration, deposition velocity of unattached {sup 218}Po and air exchange rate. It is demonstrated that with the use of additional information on surface to volume room ratio, air exchange rate ...
Separate comprehensive final reports on the status of the SRC-II Demonstration Plant Design and on operating experiences at the Ft. Lewis and P-99 SRC pilot plants were prepared after the termination of those projects. However, time constraints made it impossible to consolidate all of the pilot plant data and operating experiences and relate these to the Demonstration Plant or future plant design. Most of the experimental programs during the later stages of pilot plant operation were in direct support of specific technical uncertainties identified in design work. The results of these programs would have been of substantial use in verifying or modifying design philosophy had the project proceeded. This technical data analysis project was undertaken to consolidate the pilot plant results presented in numerous reports under DOE Contract DE-AC01-79ET10104 for operation of the pilot plants, and to relate these results to specific Demonstration Plant ...
The neutron capture cross sections of Sr-88 and Y-89 were measured in a quasi-stellar neutron spectrum for kT = 25 keV via the activation method. Relevant systematic uncertainties were determined experimentally by repeated activations under different conditions and with different samples. Gold was used as a cross section standard. The resulting stellar cross sections for kT = 30 keV are 6.13 + or - 0.18 mbarn for Sr-88 and 19.0 + or - 0.6 mbarn for Y-89. The partial cross section Sr-86(n, gamma) Sr-87m was measured to 48.1 + or - 1.2 mbarn. Compared to previous data, the associated uncertainties are reduced by factors of 3 and 5, respectively. The implications for s-process nucleosynthesis around magic neutron number N = 50 are discussed in the light of new information on neutron density and temperature. 38 refs.
The neutron capture cross sections of Sr-88 and Y-89 were measured in a quasi-stellar neutron spectrum for kT = 25 keV via the activation method. Relevant systematic uncertainties were determined experimentally by repeated activations under different conditions and with different samples. Gold was used as a cross section standard. The resulting stellar cross sections for kT = 30 keV are 6.13 + or - 0.18 mbarn for Sr-88 and 19.0 + or - 0.6 mbarn for Y-89. The partial cross section Sr-86(n, gamma) Sr-87m was measured to 48.1 + or - 1.2 mbarn. Compared to previous data, the associated uncertainties are reduced by factors of 3 and 5, respectively. The implications for s-process nucleosynthesis around magic neutron number N = 50 are discussed in the light of new information on neutron density and temperature. 38 refs.
The neutron capture cross sections of Sr-88 and Y-89 were measured in a quasi-stellar neutron spectrum for kT = 25 keV via the activation method. Relevant systematic uncertainties were determined experimentally by repeated activations under different conditions and with different samples. Gold was used as a cross section standard. The resulting stellar cross sections for kT = 30 keV are 6.13 + or - 0.18 mbarn for Sr-88 and 19.0 + or - 0.6 mbarn for Y-89. The partial cross section Sr-86(n, gamma) Sr-87m was measured to 48.1 + or - 1.2 mbarn. Compared to previous data, the associated uncertainties are reduced by factors of 3 and 5, respectively. The implications for s-process nucleosynthesis around magic neutron number N = 50 are discussed in the light of new information on neutron density and temperature.
Mechanistic models of aerosol decontamination by an overlying water pool during core debris/concrete interactions and spray removal of aerosols from a Mark I drywell atmosphere are developed. Eighteen uncertain features of the pool decontamination model and 19 uncertain features of the model for the rate coefficient of spray removal of aerosols are identified. Ranges for values of parameters that characterize these uncertain features of the models are established. Probability density functions for values within these ranges are assigned according to a set of rules. A Monte Carlo uncertainty analysis of the decontamination factor produced by water pools 30 and 50 cm deep and subcooled 0--70 K is performed. An uncertainty analysis for the rate constant of spray removal of aerosols is done for water fluxes of 0.25, 0.01, and 0.001 cm{sup 3} H{sub 2}O/cm{sup 2}-s and decontamination factors of 1.1, 2, 3.3, 10, 100, and 1000.
A stochastic linear fractional programming (SLFP) approach is developed for supporting sustainable municipal solid waste management under uncertainty. The SLFP method can solve ratio optimization problems associated with random information, where chance-constrained programming is integrated into a linear fractional programming framework. It has advantages in: (1) comparing objectives of two aspects, (2) reflecting system efficiency, (3) dealing with uncertainty expressed as probability distributions, and (4) providing optimal-ratio solutions under different system-reliability conditions. The method is applied to a case study of waste flow allocation within a municipal solid waste (MSW) management system. The obtained solutions are useful for identifying sustainable MSW management schemes with maximized system efficiency under various constraint-violation risks. The results indicate that SLFP can support in-depth analysis of the ...
This paper examined the potential of steam assisted gravity drainage (SAGD) technology for increasing productivity in the Orinoco heavy oilfields of Venezuela. A computerized simulation tool was used to generate a matrix of parameters needed to compare SAGD processes with cold production techniques in the Carabobo region of the Orinoco belt. Parameters included vertical connectivity, oil saturation, and net pay. Monte Carlo simulations and uncertainty assessments were used to generate cold production scenarios. Optimized SAGD scenarios were then designed for each case. Results of the study suggested that vertical local connectivity was an important parameter for the identification of suitable areas for EOR and SAGD. Unfavorable conditions for the application of SAGD during early production stages were identified. SAGD behaviour improved through the adjustment of injection rates during different stages of the process. It was concluded that the simulation run times ...
This paper presents a nonlinear Bayesian regression algorithm for the purpose of detecting and estimating gas plume content from hyper-spectral data. Remote sensing data, by its very nature, is collected under less controlled conditions than laboratory data. As a result, the physics-based model that is used to describe the relationship between the observed remotesensing spectra, and the terrestrial (or atmospheric) parameters that we desire to estimate, is typically littered with many unknown "nuisance" parameters (parameters that we are not interested in estimating, but also appear in the model). Bayesian methods are well-suited for this context as they automatically incorporate the uncertainties associated with all nuisance parameters into the error estimates of the parameters of interest. The nonlinear Bayesian regression methodology is illustrated on realistic simulated data from a three-layer model for longwave infrared (LWIR) measurements from a passive ...
A new performance model of the externally fired combined cycle (EFCC) is implemented in ASPEN (Advanced System for Process ENgineering), a chemical process simulator. The model accounts for interactions within and between approximately a dozen major process areas. The new model is applied to case studies to evaluate the sensitivity of process performance to the ranges of uncertainty in key model inputs such as heat losses, carbon conversion, and air leakage rates, and to illustrate how alternative designs, including steam injection and flue gas desulfurization (FGD), can affect plant thermal efficiency and net power output. The model results suggest that careful attention to the design of the FGD system is needed, especially with respect to reheat, and that steam injection may offer cost savings associated with reducing the size of the steam turbine with little or no penalty on plant output or plant efficiency. Uncertainties in the slagging ...
The half-life of "1"0"9Cd was measured by following the decay of sources from a radiochemically pure solution with two different measuring systems: an ionisation chamber and a high-purity germanium (HPGe) detector. The measurements were performed over a period of 3.6 years, i.e. about 2.8 half-lives of "1"0"9Cd. The resulting half-life values and detailed uncertainty budgets (k=1) are presented for both systems. The result obtained with the ionisation chamber, 462.36 (33) days, and the one obtained with the HPGe detector, 461.92 (76) days, are mutually consistent. The weighted mean of our measured values, T_1_/_2("1"0"9Cd)=462.29 (30) days, is consistent with the currently recommended values of 461.4 (12) days and 462.0 (3) days. From a set of selected experimental values published after 1970, a 'partially weighted mean' of T_1_/_2("1"0"9Cd)=462.36 (39) days was calculated. More measurements are needed to resolve the discrepancies among literature data and to ...
We present results from Spitzer Space Telescope observations of the mid-infrared phase variations of three short-period extrasolar planetary systems: HD 209458, HD 179949 and 51 Peg. We gathered IRAC images in multiple wavebands at eight phases of each planet's orbit. We find the uncertainty in relative photometry from one epoch to the next to be significantly larger than the photon counting error at 3.6 micron and 4.5 micron. We are able to place 2-sigma upper limits of only 2% on the phase variations at these wavelengths. At 8 micron the epoch-to-epoch systematic uncertainty is comparable to the photon counting noise and we detect a phase function for HD 179949 which is in phase with the planet's orbit and with a relative peak-to-trough amplitude of 0.00141(33). Assuming that HD 179949b has a radius R_J < R_p < 1.2R_J and a small Bond albedo, it must recirculate less than 30% of incident stellar energy to its night side at the 1-sigma ...
Model-based approaches to pattern recognition and machine vision have been proposed to overcome the exorbitant training requirements of earlier computational paradigms. However, uncertainties in data were found to lead to a combinatorial explosion of the computational complexity. This issue is related here to the roles of a priori knowledge vs. adaptive learning. What is the a-priori knowledge representation that supports learning? I introduce Modeling Field Theory (MFT), a model-based neural network whose adaptive learning is based on a priori models. These models combine deterministic, fuzzy, and statistical aspects to account for a priori knowledge, its fuzzy nature, and data uncertainties. In the process of learning, a priori fuzzy concepts converge to crisp or probabilistic concepts. The MFT is a convergent dynamical system of only linear computational complexity. Fuzzy logic turns out to be essential for reducing the combinatorial ...
Employing a recently developed Monte-Carlo model, we study the fission of 240Pu induced by neutrons with energies from thermal to just below the threshold for second chance fission. Current measurements of the mean number of prompt neutrons emitted in fission, together with less accurate measurements of the neutron energy spectra, place remarkably fine constraints on predictions of microscopic calculations. In particular, the total excitation energy of the nascent fragments must be specified to within 1MeV to avoid disagreement with measurements of the mean neutron multiplicity. The combination of the Monte-Carlo fission model with a statistical likelihood analysis also presents a powerful tool for the evaluation of fission neutron data. Of particular importance is the fission spectrum, which plays a key role in determining reactor criticality. We show that our approach can be used to develop an estimate of the fission spectrum with uncertainties several times ...
One class of gravitational wave signals LIGO is searching for consists of short duration bursts of unknown waveforms. Potential sources include core collapse supernovae, gamma ray burst progenitors, and the merger of binary black holes or neutron stars. We present a density-based clustering algorithm to improve the performance of time-frequency searches for the such gravitational-wave bursts when they are extended in time and/or frequency. We have implemented this algorithm as an extension to the QPipeline search for bursts, which currently determines the statistical significance of events based solely on the peak significance observed in minimum uncertainty regions of the time-frequency plane. Density based clustering improves the performance of such a search by considering the aggregate significance of arbitrarily shaped regions in the time-frequency plane and rejecting the isolated minimum uncertainty features expected from the background ...
The fuel composition heterogeneity effect on reactor performance parameters was assessed by refueling simulations for three DUPIC fuel options of fuel composition heterogeneity control: the fissile content adjustment, the reactivity control by slightly enriched and depleted uranium, and the reactivity control by natural uranium. For each DUPIC fuel option, the simulations were performed using 30 heterogeneous fuel types which were determined by the agglomerative hierarchical clustering method. The heterogeneity effect was considered during the refueling simulation by randomly selecting fuel types for the refueling operation. The refueling simulations of the heterogeneous core have shown that the key performance parameters such as the maximum channel power (MCP), maximum bundle power (MBP), and channel power peaking factor (CPPF) are close to those of the core that has single fuel type. For the three DUPIC fuel options, the uncertainties of MCP, MBP, and CPPF due to ...
In the frame of the use of the Relap5 thermal hydraulic code in the predictions of LOCA transient scenarios in PWRs and considering the recent development of a methodology to evaluate the related uncertainty, the response to a Small Break LOCA of Eastern and Western type PWRs has been analyzed. A four loop/horizontal Steam Generator WWER-1000 (KOZLODUY in Bulgaria) and a two loop/vertical U-tubes Steam Generator Westinghouse (KRSKO in Slovenia) nuclear power plants have been considered in the analysis. The reference transient is a 2% equivalent cold leg break accident, without High Pressure Injection System intervention, as specified in the frame of a ``counterpart test`` activity involving experimental tests on four Integral Test Facilities: LOBI (European Community), SPES (Italy), BETHSY (France) and LSTF (Japan). The code results in the two cases, also taking into account the related uncertainty as evaluated by means of the aforementioned ...
The total half-life and the half-life for spontaneous fission are evaluated for the various long-lived nuclides of interest. Recommended values are presented for /sup 241/Am, /sup 242m/Am, /sup 243/Am, /sup 242/Cm, /sup 243/Cm, /sup 244/Cm, /sup 245/Cm, /sup 246/Cm, /sup 247/Cm, /sup 248/Cm, and /sup 250/Cm. The uncertainties are provided at the 95% confidence limit for each of the recommended values.
The total half-life and the half-life for spontaneous fission are evaluated for the various long-lived nuclides of interest. Recommended values are presented for "2"4"1Am, "2"4"2Am, "2"4"3Am, "2"4"2Cm, "2"4"3Cm, "2"4"4Cm, "2"4"5Cm, "2"4"6Cm, "2"4"7Cm, "2"4"8Cm, and "2"5"0Cm. The uncertainties are provided at the 95% confidence limit for each of the recommended values. (author).
Measurements of the half-lives of some long-lived nuclides of elements Z = 92, 94, 95 and 96 have been compiled and evaluated. Recommended values are presented for {sup 232-236,238}U, for {sup 236,238-242,244}Pu, for {sup 241,242m,243}Am, and for {sup 242-248,250}Cm. Values are presented for both spontaneous fission half-life and total half-life. Problems with reported uncertainties are also discussed. (author).
Considerable potential exists for increasing the annual efficiency of line-focus collectors by reducing receiver heat losses. Five alternate receiver designs are compared with a standard design. The comparison is based on annual collector-field efficiency using optimized receiver designs. Of the receivers studied, the all-glass design and the cavity design provide the greatest increases in efficiency. Average fluid temperatures range from 200/sup 0/ to 450/sup 0/C. As a guide for further study, areas of uncertainty and potential problems are identified.
According to Schumpeter, the creative process of economic development can be divided into the stages of invention, innovation (commercialization) and imitation. Each stage is associated with specific skills. This paper examines whether Schumpeter?s assertion was correct, i.e. whether the invention and innovation stages should be undertaken by different agents. In addition, we examine whether there is a rationale for the Schumpeterian entrepreneur to include the inventor in the commercialization process. Combining the abilities of the entrepreneur and the inventor may serve to facilitate customer adaptation, strengthen knowledge transfers and reduce uncertainty, thereby expanding market opportunities. Based on a unique database covering Swedish patents granted to individuals and small firms...
This paper describes the phenomenology of nuclear explosions and technologies for their detection as relevant to On-Site Inspection (OSI) for a comprehensive test-ban (CTB). Our experience with the US nuclear test program which has been primarily carried out at the Nevada Test Site (NTS) and in the Pacific Ocean. The goals of OSI are to resolve ambiguous events, reduce uncertainty, deter attempts at evasion, and provide responsive and technically competent means of confirming the occurrence of a nuclear explosion should deterrence fail. These goals would include finding evidence of an evasive nuclear explosion or evidence that the event was non-nuclear, such as an earthquake or large chemical explosion.
This paper presents a novel design methodology, based on shaping the system frequency response, for the generation of an appropriate residual signal that is sensitive to sensor faults in the presence of model uncertainty and exogenous unknown (unmeasured) disturbances. An integrated feedback controller design and robust frequency-based fault detection approach is proposed for Single-Input/Single-Output systems. The effciency of the proposed method is demonstrated on a Single Machine Innite Bus (SMIB) power system that achieves a coordinate power system stabilizer with satisfactory sensor fault detection capabilities.
There is a growing interest on dynamic and broader concepts of deprivation such as vulnerability, which takes in to account the destitution of individuals from future shocks. We use the framework of decision making under uncertainty to arrive at a new measure of vulnerability to poverty. We highlight the importance of current standard of living to better capture the notion of vulnerability. In conceptualizing the new class of measures of vulnerability, we thus move beyond the standard expected poverty measures that is commonly found in the literature. We also axiomatically characterize the new class of measure and discuss some of its properties.
In order to obtain the resonance parameters in a single energy range and the corresponding covariance matrix, a reevaluation of 239Pu was performed with the code SAMMY. The most recent experimental data were analyzed or reanalyzed in the energy range thermal to 2.5 keV. The normalization of the fission cross section data was reconsidered by taking into account the most recent measurements of Weston et al. and Wagemans et al. A full resonance parameter covariance matrix was generated. The method used to obtain realistic uncertainties on the average cross section calculated by SAMMY or other processing codes was examined.
An accelerator experiment was performed using a low-energy antiproton beam to measure antiproton detection efficiency of BESS, a balloon-borne spectrometer with a superconducting solenoid. Measured efficiencies showed good agreement with calculated ones derived from the BESS Monte Carlo simulation based on GEANT/GHEISHA. With detailed verification of the BESS simulation, the relative systematic error of detection efficiency derived from the BESS simulation has been determined to be {+-}5%, compared with the previous estimation of {+-}15% which was the dominant uncertainty for measurements of cosmic-ray antiproton flux.
Four major reasons why municipal resource recovery operations are uneconomical are analyzed. These reasons are: alternative municipal waste disposal methods are artificially underpriced when the costs of meeting modern environmental standards are considered; high capital costs related to the procurement of resource recovery systems and the marketing of recovered resources; uncertainties associated with the costs and performance of resource recovery technologies; and construction and operating risks of municipal waste resource recovery systems. If resource recovery is to become economical, purchasers of plants must develop innovative process designs and equipment and formulate new operating and maintenance procedures. (1 photo)
A key comparison has been made between the air-kerma standards of the ARPANSA and the BIPM in the low-energy X-ray range. The results show the standards to be in agreement at the level of the combined standard uncertainty of 7.0 parts in 10"3 for the 10 kV radiation quality and 3.7 parts in 10"3 for all other beam qualities. The results are analysed and presented in terms of degrees of equivalence, suitable for entry in the BIPM key comparison database. (authors)
We consider energy investment, when a choice has to be made between fossil fuel and biomass fired production technologies. A dynamic model is presented to illustrate the effect of the different degrees of input price uncertainty on the choice of technology and the timing of the investment. It is shown that when the choice of technology is irreversible, it may be optimal to postpone the investment even if it would otherwise be optimal to invest in one or both of the plant types. We provide a numerical example based on cost, estimates of two different power plant types. (author)
We discuss the inclusive production of D{sup *{+-}} mesons in {gamma}p collisions at DESY HERA, based on a calculation at next-to-leading order in the general-mass variable-flavor-number scheme. In this approach, MS subtraction is applied in such a way that large logarithmic corrections are resummed in universal parton distribution and fragmentation functions and finite mass terms are taken into account. We present detailed numerical results for a comparison with data obtained at HERA and discuss various sources of theoretical uncertainties. (orig.)
Correct prediction of the fission products inventory in irradiated nuclear fuels is essential for accurate estimation of fuel burnup, establishing proper requirements for spent fuel transportation and storage, materials accountability and nuclear forensics. Such prediction is impossible without accurate knowledge of neutron induced fission yields. The uncertainty of the fission yields reported in the ENDF/B-VII.0 library is not uniform across all of the data and much of the improvement is desired for certain fissioning isotopes and fission products. We discuss our measurements of cumulative fission yields in nuclear fuels irradiated in thermal and fast reactor spectra using Inductively Coupled Plasma Mass Spectrometry. (author)
Correct prediction of the fission products inventory in irradiated nuclear fuels is essential for accurate estimation of fuel burnup, establishing proper requirements for spent fuel transportation and storage, materials accountability and nuclear forensics. Such prediction is impossible without accurate knowledge of neutron induced fission yields. The uncertainty of the fission yields reported in the ENDF/B-VII.0 library is not uniform across all of the data and much of the improvement is desired for certain fissioning isotopes and fission products. We discuss our measurements of cumulative fission yields in nuclear fuels irradiated in thermal and fast reactor spectra using Inductively Coupled Plasma Mass Spectrometry.
Fission rate assessments are being made in FFTF to provide input for determination of power distribution, peak power, total power, fuel burnup distribution, conversion ration and neutron spectral information by the multiple foil reaction rate method. A goal of the initial FFTF Characterization Program is to measure isotopic fission rates to an accuracy of 2 to 5% throughout FFTF by radiometric techniques. To achieve this goal, measurements were made in the FFTF In-Reactor Thimble to reduce the uncertainties of key parameters needed for radiometric fission rate mapping of the FFTF core.
Financing space solar power generation programmes has several inherent difficulties. Such large-scale projects are usually easily defined with an expected economic return, construction time, useful service life and defined management structure. As yet, solar power satellites for power generation possess none of these as the idea exists conceptually and the technology still needs to be developed. Methods for overcoming these uncertainties and securing financial backing are described. Venture capital could finance a research/marketing firm. US Government support through a cost plus short-term monopoly to facilitate private debt financing could provide an answer. (UK)
Economic depreciation of similar cost recovery schemes delay cash return of investment. Such delay may require new types of securities. Due to uncertainty of regulatory action and technology over the prolonged recovery life of the projects, investors may require a higher return, thereby raising the cost of capital. Utility managements might eschew long lived investment, too, even if cost effective to the consumer. Alternatives exist that would approximate the price signals of economic depreciation without discouraging investment. The importance of upfront returns to the investment process should not be minimized. 2 figs., 3 refs. (AV)
This document presents a detailed schedule for the implementation of the strategy for managing defense remote-handled (RH) transuranic (TRU) waste. The baseline management strategy was defined in the Defense Remote-Handled Transuranic Waste Cost/Schedule Optimization Study and is summarized in this document. Also included are revised RH TRU waste inventory projections, current site management plans, a list of key decision points and milestones, and a discussion of uncertainties associated with management of RH TRU waste. The plans are summarized in a detailed schedule diagram and in an RH TRU waste work off diagram. 9 refs., 5 figs., 4 tabs.
A central feature of the endocrine pathophysiology of septic shock is thought to be the existence of adrenal dysfunction. Based on changes in glucocorticoid secretion and responsiveness, protein binding, and activity. These changes have been described by the terms "Relative Adrenal Insufficiency" (RAI), or "Critical Illness Related Corticosteroid Insufficiency" (CIRCI), and form part of the rationale for trials of glucocorticoid treatment in septic shock. Diagnostic criteria for these conditions have been based on plasma cortisol profiles and have proven notoriously difficult to establish. The uncertainty in this area arises from the inability of current tests to clearly identify who is truly glucocorticoid "deficient" at a cellular level, and hence who requires supplemental glucocorticoid...
An accelerator beam experiment was performed using a low-energy antiproton beam to measure antiproton detection efficiency of the BESS detector. Measured and calculated efficiencies derived from the BESS Monte Carlo simulation based on GRANT/GHEISHA showed good agreement. With detailed verification of the BESS simulation, the relative systematic error of detection efficiency derived from the BESS simulation has been determined to be {+-}5%, compared with the previous estimation of {+-}15% which was the dominant uncertainty for measurements of cosmic-ray antiproton flux. (author)
A generalised procedure for quantifying the benefits of household biogas plants is presented. The sensitivity of the procedure to the uncertainty in input prices is reduced through the assumption of incremental benefits from the biogas plant. These benefits are quantified in terms of the quantity of fuelwood for which the biogas substitutes in cooking, the quantity of kerosene replaced through the use of biogas for lighting and the diesel fuel displaced through the use of a biogas fuelled dual-fuel engine for motive power. Sensitivity of the monetary benefits for these parameters is examined in order to identify variables which influence the viability of the technology to the end user. (author).
The available experimental data on the (/sup 3/He,n) reaction between the ground states of even-even nuclei and lowest 1/2/sup -/ levels of odd-A nuclei in the Aapprox.=100 region are analyzed in a systematic way by the DWBA. The deduced relative intensities of these two-proton transfers, and their uncertainties, are compared to the predictions of various nuclear models. In particular, the influence of the finite dimension of the configuration space available to the transferred protons, and of the blocking effect of a 2p1/2/sup -/ proton, are examined. (orig.).
This paper presents the regulatory experience gained from Wolsong Units 2,3 and 4 - Special Safety System Instrumentation Uncertainty for Trip Setpoint and Allowable Values. The equipment diversity method for the defense against common mode failure was applied to the transmitters of shutdown system number 2. However the Units experienced an unexpected drift problem with which the performance did not meet the Technical Specification (Tech Spec) Surveillance Requirements (SR). Discussed are the background, status and corrective actions, regulatory positions and issues to be solved for the drift problem. It was an instrument uncertainty methodology that the designer of safety system should have shown when the drift problem occurred. For deeper understanding of the problem, we present the background of Tech Spec SR for setpoints in Korean PWR and in CANDU reactors. The Setpoint Verification Test(SVT) and Calibration Test(CT) shall be achieved by ...
The previous 58Ni and 60Ni set of resonance parameters (ENDF/B-VII-0, JEFF-3, etc.) was based on the SAMMY analysis of Oak Ridge National Laboratory neutron transmission, scattering cross section and capture cross section measurements by C. M. Perey et al. The present results were obtained by adding to the SAMMY experimental data base the capture cross sections measured recently at the Oak Ridge Linear Electron Accelerator by Guber et al. and the Geel Electron Linear Accelerator very high-resolution neutron transmission measurements performed by Brusegan et al. A complete resonance parameter covariance matrix (RPCM) was obtained from the SAMMY analysis of the experimental database. The data sets were made consistent, when needed, by adjusting the neutron energy scales, the normalization coefficients, and the background corrections. The RPCM allows the calculation of the cross section uncertainties due mainly to statistical errors in the experimental data. The ...
The previous {sup 58}Ni and {sup 60}Ni set of resonance parameters (Endf/B7.O, Jeff-3, etc.) was based on the SAMMY analysis of Oak Ridge National Laboratory neutron transmission, scattering cross section and capture cross section measurements by C.M. Perey et al. The present results were obtained by adding to the SAMMY experimental database the capture cross sections measured recently at the Oak Ridge Linear Electron Accelerator by Guber et al. and the Geel Electron Linear Accelerator and very high-resolution neutron transmission measurements performed by Brusegan et al. A complete resonance parameter covariance matrix (RPCM) was obtained from the SAMMY analysis of the experimental database. The data sets were made consistent, when needed, by adjusting the neutron energy scales, the normalization coefficients, and the background corrections. The RPCM allows the calculation of the cross section uncertainties due mainly to statistical errors in the experimental ...
The uncertainty associated with the sorption coefficient, or K{sub d} value, is one of the key uncertainties in estimating risk associated with burying low-level nuclear waste in the subsurface. The objective of this study was to measure >648 K{sub d} values and provide a measure of the range and distribution (normal or log-normal) of radionuclide K{sub d} values appropriate for the E-Area disposal site, within the Savannah River Site, near Aiken South Carolina. The 95% confidence level for the mean K{sub d} was twice the mean in the Aquifer Zone (18-30.5 m depth), equal to the mean for the Upper Vadose Zone (3.3-10 m depth), and half the mean for the Lower Vadose Zone (3.10-18 m depth). The distribution of K{sub d} values was log normal in the Upper Vadose Zone and Aquifer Zone, and normal in the Lower Vadose Zone. To our knowledge, this is the first report of natural radionuclide Kd variability in the literature. Using ranges and ...
Primary standardisation was performed on a solution of "1"8F using the 4#pi##beta#-#gamma# coincidence counting efficiency-tracing extrapolation method with "6"0Co used as a tracer nuclide. The result was used to calibrate the ANSTO secondary standard ionisation chamber which is used to disseminate Australian activity standards for gamma emitters. Using the secondary activity standard for "1"8F, the Capintec CRC-712M dose calibrator at the Australian National Medical Cyclotron (NMC) Positron Emission Tomography (PET) Quality Control (QC) Section was calibrated. The dial setting number recommended by the manufacturer for the measurement of the activity of "1"8F is 439. In this work, the dial setting numbers for the activity measurement of the solution of "1"8F in Wheaton vials were experimentally determined to be 443+/-12, 446+/-12, 459+/-11, 473+/-15 for 0.1, 1, 4.5 and 9ml solution volumes, respectively. The uncertainties given above are expanded ...