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Pandey, Alok K., R. Krishankumar, Dragan Pamucar, Fausto Cavallaro, Abbas Mardani, Samarjit Kar, and K. S. Ravichandran. "A Bibliometric Review on Decision Approaches for Clean Energy Systems under Uncertainty." Energies 14, no. 20 (October 19, 2021): 6824. http://dx.doi.org/10.3390/en14206824.
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This paper aims to provide a bibliometric review on the diverse decision approaches in uncertain contexts for clean energy system (CES) assessment. A total of 126 publications are analyzed. Previous reviews on CES have discussed several research questions on the decision methods and the applicability of evaluating CES, along with the factors associated with CESs. In the present study, we focus on the bibliometric aspect that attempts to address questions related to the prominence of authors, countries/regions that focus on the current theme, impact of journals, importance of articles in the research community, and so on. The window considered for the study is from 2018 to 2021, with the motive to extend the review process from the preceding works. A review model is presented to address the questions based on the literature evidence. The results infer that CESs are the most viable mode for sustainable development, and the use of decision approaches is apt for the assessment of CESs.
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LIBERMAN, ALIDA. "Permissible Promise-Making Under Uncertainty." Journal of the American Philosophical Association 5, no. 4 (2019): 468–86. http://dx.doi.org/10.1017/apa.2019.26.
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AbstractI outline four conditions on permissible promise-making: the promise must be for a morally permissible end, must not be deceptive, must be in good faith, and must involve a realistic assessment of oneself. I then address whether promises that you are uncertain you can keep can meet these four criteria, with a focus on campaign promises as an illustrative example. I argue that uncertain promises can meet the first two criteria, but that whether they can meet the second two depends on the source of the promisor's uncertainty. External uncertainty stemming from outside factors is unproblematic, but internal uncertainty stemming from the promisor's doubts about her own strength leads to promises that are in bad faith or unrealistic. I conclude that campaign promises are often subject to internal uncertainty and are therefore morally impermissible to make, all else being equal.
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Rababa, Mohammad. "The Role of Nurses’ Uncertainty in Decision-Making Process of Pain Management in People with Dementia." Pain Research and Treatment 2018 (August 1, 2018): 1–7. http://dx.doi.org/10.1155/2018/7281657.
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Pain in people with dementia (PWD) is underassessed and undertreated. Treatment of pain in people with dementia goes awry because of poor assessment, poor treatment, and factors related to nursing decision-making skills. Several theoretical models addressed the role of nurses’ critical thinking and decision-making skills in pain treatment, like the cognitive continuum theory (CCT) and the adaptive pain management (APT). Only the Response to Certainty of Pain (RCP) model was the first model to posit relationships between nurses' uncertainty, pain assessment, and patient outcomes. Gilmore-Bykovskyi and Bowers developed the RCP, which incorporates the concept of uncertainty and how it relates to the problem of unrelieved pain in PWD. The RCP model has the potential to provide good understanding of the problem of unrelieved pain in people with dementia. It also could help to develop a research study that brings comfort to an often neglected and vulnerable population.
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Adshead, Gwen. "Healing ourselves: ethical issues in the care of sick doctors." Advances in Psychiatric Treatment 11, no. 5 (September 2005): 330–37. http://dx.doi.org/10.1192/apt.11.5.330.
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In this paper I review some of the ethical dilemmas that arise when psychiatrists are involved in the assessment and treatment of medical colleagues. Special attention needs to be paid to the context of the relationship between the psychiatrist and the doctor-patient, and to the extent to which the patient is seeking help voluntarily or at the request of a third party. Psychiatrists may find themselves uncertain about how to meet the ethical demands of their duties to the patient and their duties to the public, when these conflict.
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Küttenbaum, Stefan, Stefan Maack, Alexander Taffe, and Thomas Braml. "On the treatment of measurement uncertainty in stochastic modeling of basic variables." Acta Polytechnica CTU Proceedings 36 (August 18, 2022): 109–18. http://dx.doi.org/10.14311/app.2022.36.0109.
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The acquisition and appropriate processing of relevant information about the considered system remains a major challenge in assessment of existing structures. Both the values and the validity of computed results such as failure probabilities essentially depend on the quantity and quality of the incorporated knowledge. One source of information are onsite measurements of structural or material characteristics to be modeled as basic variables in reliability assessment. The explicit use of (quantitative) measurement results in assessment requires the quantification of the quality of the measured information, i.e., the uncertainty associated with the information acquisition and processing. This uncertainty can be referred to as measurement uncertainty. Another crucial aspect is to ensure the comparability of the measurement results.This contribution attempts to outline the necessity and the advantages of measurement uncertainty calculations in modeling of measurement data-based random variables to be included in reliability assessment. It is shown, how measured data representing time-invariant characteristics, in this case non-destructively measured inner geometrical dimensions, can be transferred into measurement results that are both comparable and quality-evaluated. The calculations are based on the rules provided in the guide to the expression of uncertainty in measurement (GUM). The GUM-framework is internationally accepted in metrology and can serve as starting point for the appropriate processing of measured data to be used in assessment. In conclusion, the effects of incorporating the non-destructively measured data into reliability analysis are presented using a prestressed concrete bridge as case-study.
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Haslbeck, Matthias, Robert Kroyer, Andreas Taras, and Thomas Braml. "Uncertainty assessment for the Bayesian updating process of concrete strength properties." Acta Polytechnica CTU Proceedings 36 (August 18, 2022): 76–83. http://dx.doi.org/10.14311/app.2022.36.0076.
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Reassessment of infrastructure buildings has become an essential approach to deal with increasing traffic loads on ageing infrastructure buildings and to verify the service-life of those structures. Good estimation of the actual material properties is highly relevant for reliable structural reassessment. Although this holds for all building materials, the importance of good parameter estimation is of special importance for concrete structures, where the strength properties show relatively high variation and where the nominal strength properties tend to be too conservative. Modern design guidelines allow to make use of scientific methods such as Bayesian Updating of material properties to enable a more realistic consideration of the actual material properties in the reassessment of existing structures. However, guidelines for application and experience with those methods are not yet reported much or are rather vague [1]. The presented study focuses on the effect of the Bayesian Updating process for material parameters with special emphasis on the number and sampling location of test specimens as well as on the accuracy and confidence in the obtained posterior distribution, since sampling also includes a certain margin of uncertainty. The investigation on the methodological potential and on the uncertainty margin in the updating process in this contribution uses a batch of 14 test results on the concrete compressive strength obtained from drill cores along with the inherent measurement uncertainties from the testing procedure. After a short review of Bayes’ Theorem, the Markov Chain Monte Carlo Method (MCMC) and the bootstrap methodology, all combinations of subsamples of size 1, 3 and 5 specimens were built and provided to the Bayes’ updating procedure via MCMC to determine the posterior distributions. The series of obtained posterior distributions for a certain subsample was used to determine the uncertainty in the Bayesian Updating process by evaluation of the scatter in the expected value, the standard deviation and the 5 %-quantile of the updated distribution. The simulations show the importance of an adequate sample size and quantify the uncertainties arising from the limited number of observations.
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Ning, T., J. Wang, G. Elgered, G. Dick, J. Wickert, M. Bradke, M. Sommer, R. Querel, and D. Smale. "The uncertainty of the atmospheric integrated water vapour estimated from GNSS observations." Atmospheric Measurement Techniques 9, no. 1 (January 18, 2016): 79–92. http://dx.doi.org/10.5194/amt-9-79-2016.
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Abstract. Within the Global Climate Observing System (GCOS) Reference Upper-Air Network (GRUAN) there is a need for an assessment of the uncertainty in the integrated water vapour (IWV) in the atmosphere estimated from ground-based global navigation satellite system (GNSS) observations. All relevant error sources in GNSS-derived IWV are therefore essential to be investigated. We present two approaches, a statistical and a theoretical analysis, for the assessment of the uncertainty of the IWV. The method is valuable for all applications of GNSS IWV data in atmospheric research and weather forecast. It will be implemented to the GNSS IWV data stream for GRUAN in order to assign a specific uncertainty to each data point. In addition, specific recommendations are made to GRUAN on hardware, software, and data processing practices to minimise the IWV uncertainty. By combining the uncertainties associated with the input variables in the estimations of the IWV, we calculated the IWV uncertainties for several GRUAN sites with different weather conditions. The results show a similar relative importance of all uncertainty contributions where the uncertainties in the zenith total delay (ZTD) dominate the error budget of the IWV, contributing over 75 % of the total IWV uncertainty. The impact of the uncertainty associated with the conversion factor between the IWV and the zenith wet delay (ZWD) is proportional to the amount of water vapour and increases slightly for moist weather conditions. The GRUAN GNSS IWV uncertainty data will provide a quantified confidence to be used for the validation of other measurement techniques.
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Bravo-Aranda, Juan Antonio, Livio Belegante, Volker Freudenthaler, Lucas Alados-Arboledas, Doina Nicolae, María José Granados-Muñoz, Juan Luis Guerrero-Rascado, et al. "Assessment of lidar depolarization uncertainty by means of a polarimetric lidar simulator." Atmospheric Measurement Techniques 9, no. 10 (October 7, 2016): 4935–53. http://dx.doi.org/10.5194/amt-9-4935-2016.
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Abstract. Lidar depolarization measurements distinguish between spherical and non-spherical aerosol particles based on the change of the polarization state between the emitted and received signal. The particle shape information in combination with other aerosol optical properties allows the characterization of different aerosol types and the retrieval of aerosol particle microphysical properties. Regarding the microphysical inversions, the lidar depolarization technique is becoming a key method since particle shape information can be used by algorithms based on spheres and spheroids, optimizing the retrieval procedure. Thus, the identification of the depolarization error sources and the quantification of their effects are crucial. This work presents a new tool to assess the systematic error of the volume linear depolarization ratio (δ), combining the Stokes–Müller formalism and the complete sampling of the error space using the lidar model presented in Freudenthaler (2016a). This tool is applied to a synthetic lidar system and to several EARLINET lidars with depolarization capabilities at 355 or 532 nm. The lidar systems show relative errors of δ larger than 100 % for δ values around molecular linear depolarization ratios (∼ 0.004 and up to ∼ 10 % for δ = 0.45). However, one system shows only relative errors of 25 and 0.22 % for δ = 0.004 and δ = 0.45, respectively, and gives an example of how a proper identification and reduction of the main error sources can drastically reduce the systematic errors of δ. In this regard, we provide some indications of how to reduce the systematic errors.
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Hassel, Thomas, Volker Mintzlaff, Joachim Stahlmann, Klaus-Jürgen Röhlig, and Anne Eckhardt. "Workshop Safety and Uncertainty." Safety of Nuclear Waste Disposal 1 (November 10, 2021): 309–10. http://dx.doi.org/10.5194/sand-1-309-2021.
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Abstract. Uncertainties have a significant influence on the assessment and evaluation of the safety of a repository system for high-level radioactive waste. Significant reasons for uncertainties concerning the safety barriers of a repository are: Conducting experiments on the long-term behaviour of the repository in real time is impossible due to the long assessment period over which the repository is supposed to ensure safety. The extrapolation of results from time-limited experiments, e.g. on the corrosion of container materials, to other temporal dimensions is associated with uncertainties. Uncertainties also stem from differences between experimental situations, e.g. laboratory experiments, and the real conditions in the repository. The interpretation of empirical results can be ambiguous and therefore associated with uncertainties. The development of future impacts on the barriers can only be predicted to a limited extent. Therefore, the future behaviour of the barriers can only be extrapolated into the future to a limited extent on the basis of experience gained in the past and uncertainties remain. The construction and operation of the repository will disturb its natural environment. The geological environment in which the repository is embedded behaves differently from a natural geological system, which in turn is associated with uncertainties. A major source of uncertainties is also the natural inhomogeneity of the geological barrier, which can only be investigated on a sample basis. During excavation and other construction work underground, unforeseen situations are to be expected, which make it necessary to act situationally. The complexity of the disposal path where decisions are interlinked, creates further uncertainties. Last but not least, it is uncertain what further findings on the safety of the repository will be obtained in the future along the disposal path. For safety studies, especially studies on the long-term safety of repository systems, methods and conventions for dealing with uncertainties have become established internationally. In the site selection process, these methods and conventions are questioned and, if necessary, must be further developed so that they ultimately also convince the interested public and scientists from other disciplines. In the workshop, uncertainties will be examined in particular from the perspectives of a civil engineer and of a materials researcher with introductory presentations. This will be followed by a moderated discussion. The workshop will focus on the preliminary safety investigations; however, the discussion can also refer to later phases of the disposal path. The aim of the discussion is to arrive at a common synthesis: Where have good practices for dealing with uncertainties already been established? Where is there still a need for research and clarification? What needs to be considered in the dialogue with the interested public?
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Glantz, P., and M. Tesche. "Assessment of two aerosol optical thickness retrieval algorithms applied to MODIS Aqua and Terra measurements in Europe." Atmospheric Measurement Techniques 5, no. 7 (July 19, 2012): 1727–40. http://dx.doi.org/10.5194/amt-5-1727-2012.
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Abstract. The aim of the present study is to validate AOT (aerosol optical thickness) and Ångström exponent (α), obtained from MODIS (MODerate resolution Imaging Spectroradiometer) Aqua and Terra calibrated level 1 data (1 km horizontal resolution at ground) with the SAER (Satellite AErosol Retrieval) algorithm and with MODIS Collection 5 (c005) standard product retrievals (10 km horizontal resolution), against AERONET (AErosol RObotic NETwork) sun photometer observations over land surfaces in Europe. An inter-comparison of AOT at 0.469 nm obtained with the two algorithms has also been performed. The time periods investigated were chosen to enable a validation of the findings of the two algorithms for a maximal possible variation in sun elevation. The satellite retrievals were also performed with a significant variation in the satellite-viewing geometry, since Aqua and Terra passed the investigation area twice a day for several of the cases analyzed. The validation with AERONET shows that the AOT at 0.469 and 0.555 nm obtained with MODIS c005 is within the expected uncertainty of one standard deviation of the MODIS c005 retrievals (ΔAOT = ± 0.05 ± 0.15 · AOT). The AOT at 0.443 nm retrieved with SAER, but with a much finer spatial resolution, also agreed reasonably well with AERONET measurements. The majority of the SAER AOT values are within the MODIS c005 expected uncertainty range, although somewhat larger average absolute deviation occurs compared to the results obtained with the MODIS c005 algorithm. The discrepancy between AOT from SAER and AERONET is, however, substantially larger for the wavelength 488 nm. This means that the values are, to a larger extent, outside of the expected MODIS uncertainty range. In addition, both satellite retrieval algorithms are unable to estimate α accurately, although the MODIS c005 algorithm performs better. Based on the inter-comparison of the SAER and MODIS c005 algorithms, it was found that SAER on the whole is able to obtain results within the expected uncertainty range of MODIS Aqua and Terra observations.
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Glantz, P., and M. Tesche. "Assessment of diverse algorithms applied on MODIS Aqua and Terra data over land surfaces in Europe." Atmospheric Measurement Techniques Discussions 5, no. 2 (March 19, 2012): 2363–93. http://dx.doi.org/10.5194/amtd-5-2363-2012.
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Abstract. The aim of the present study is to validate AOT (aerosol optical thickness) and Ångström exponent (α), obtained with the SAER (Satellite AErosol Retrieval) algorithm for MODIS (MODerate resolution Imaging Spectroradiometer) Aqua and Terra calibrated level 1 data (1 km horizontal resolution at ground) and MODIS Collection 5 (c005) standard product retrievals (10 km), against AERONET (AErosol RObotic NETwork) observations over land surfaces in Europe. The three time periods investigated in this study have been chosen to enable a validation of the algorithm for a maximal possible variation in sun elevations. For several of the cases analyzed here the Aqua and Terra satellites passed the investigation area twice during a day. Thus, beside a variation in the sun elevation the satellite retrievals have also on a daily basis been performed with a significant variation in the satellite-viewing geometry. An inter-comparison of the two algorithms has also been performed. The validation with AERONET shows that the MODIS c005 retrieved AOT is, for the wavelengths 0.469 and 0.500 nm, on the whole within the expected uncertainty for one standard deviation of the MODIS c005 retrievals over Europe (Δ AOT = ±0.05±0.15 AOT). The SAER estimated AOT for the wavelength 0.443 nm also agree reasonable well with AERONET. Thus, the majority of the SAER AOT values are within the MODIS expected uncertainty range, although somewhat larger root mean square deviation occurs compared to the results obtained with the MODIS c005 algorithm. The discrepancy between SAER and AERONET AOT is, however, substantially larger for the wavelength 488 nm, which means that the values are to a large extent outside of the expected MODIS uncertainty range. Both satellite retrieval algorithms are unable to estimate α accurately, although the MODIS c005 algorithm performs better. Based on the inter-comparison of the SAER and MODIS c005 algorithms it was found that the SAER is able to obtain results within the expected uncertainty range of MODIS for Aqua and Terra observations during periods 1 and 3. The same was found for MODIS Aqua observations during period 2 but only for AOT below 0.5.
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Kinne, S., M. Schulz, C. Textor, S. Guibert, Y. Balkanski, S. E. Bauer, T. Berntsen, et al. "An AeroCom initial assessment – optical properties in aerosol component modules of global models." Atmospheric Chemistry and Physics Discussions 5, no. 5 (September 8, 2005): 8285–330. http://dx.doi.org/10.5194/acpd-5-8285-2005.
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Abstract. The AeroCom exercise diagnoses multi-component aerosol modules in global modeling. In an initial assessment simulated global distributions for mass and mid-visible aerosol optical thickness (aot) were compared among 20 different modules. Model diversity was also explored in the context of previous comparisons. For the component combined aot general agreement has improved for the annual global mean. At 0.11 to 0.14, simulated aot values are at the lower end of global averages suggested by remote sensing from ground (AERONET ca. 0.135) and space (satellite composite ca. 0.15). More detailed comparisons, however, reveal that larger differences in regional distribution and significant differences in compositional mixture remain. Of particular concern are large model diversities for contributions by dust and carbonaceous aerosol, because they lead to significant uncertainty in aerosol absorption (aab). Since aot and aab, both, influence the aerosol impact on the radiative energy-balance, the aerosol (direct) forcing uncertainty in modeling is larger than differences in aot might suggest. New diagnostic approaches are proposed to trace model differences in terms of aerosol processing and transport: These include the prescription of common input (e.g. amount, size and injection of aerosol component emissions) and the use of observational capabilities from ground (e.g. measurements networks) or space (e.g. correlations between aerosol and clouds).
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Kinne, S., M. Schulz, C. Textor, S. Guibert, Y. Balkanski, S. E. Bauer, T. Berntsen, et al. "An AeroCom initial assessment – optical properties in aerosol component modules of global models." Atmospheric Chemistry and Physics 6, no. 7 (May 29, 2006): 1815–34. http://dx.doi.org/10.5194/acp-6-1815-2006.
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Abstract. The AeroCom exercise diagnoses multi-component aerosol modules in global modeling. In an initial assessment simulated global distributions for mass and mid-visible aerosol optical thickness (aot) were compared among 20 different modules. Model diversity was also explored in the context of previous comparisons. For the component combined aot general agreement has improved for the annual global mean. At 0.11 to 0.14, simulated aot values are at the lower end of global averages suggested by remote sensing from ground (AERONET ca. 0.135) and space (satellite composite ca. 0.15). More detailed comparisons, however, reveal that larger differences in regional distribution and significant differences in compositional mixture remain. Of particular concern are large model diversities for contributions by dust and carbonaceous aerosol, because they lead to significant uncertainty in aerosol absorption (aab). Since aot and aab, both, influence the aerosol impact on the radiative energy-balance, the aerosol (direct) forcing uncertainty in modeling is larger than differences in aot might suggest. New diagnostic approaches are proposed to trace model differences in terms of aerosol processing and transport: These include the prescription of common input (e.g. amount, size and injection of aerosol component emissions) and the use of observational capabilities from ground (e.g. measurements networks) or space (e.g. correlations between aerosol and clouds).
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LINDSAY, KATE M., CLARK P. SVRCEK, and DANIEL W. SMITH. "EVALUATION OF CUMULATIVE EFFECTS ASSESSMENT INFRIENDS OF THE WEST COUNTRY ASSOCIATIONv.CANADAAND LAND USE PLANNING ALTERNATIVES." Journal of Environmental Assessment Policy and Management 04, no. 02 (June 2002): 151–69. http://dx.doi.org/10.1142/s146433320200098x.
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In 1994, Sunpine Forest Products Ltd. sought permits from Alberta government to construct a permanent log hauling road and approvals from the federal government for construction of required bridges associated with the road. A concerned citizens group challenged the Federal Government's subsequent bridge approvals in court, claiming that cumulative effects assessment was not adequately conducted under Canadian Environmental Assessment Act. The original Sunpine court decision agreed with the citizen group that the federal government erred in law by not including related projects and adequately considering associated cumulative effects, sending the approval back to the federal government for reconsideration. Government regulators, industrial foresters, and environmental groups across Canada awaited the appeal to the Sunpine federal court decision. The Sunpine Appeal reversed the original position with much relief from industry and government. The Sunpine case raises important issues about how federal and provincial authorities address environmental impacts, uncertainty in scoping assessments, factors to be considered, and cumulative effect assessments. This paper evaluates the cumulative effects assessment processes followed in the Sunpine case study under the Canadian Environmental Assessment Act within an analysis framework of comprehensiveness, fairness, efficiency, and effectiveness. Land use planning models, like the British Columbia land resource management plans and Mackenzie Valley Resource Management Act, offer alternative approaches to legislated cumulative effects processes. Sustainability may be better realised with a combination of strategic environmental assessment tools, utilising environmental assessment at the project-level within the context of a regional resource planning process.
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Eiró, Flávio, and Martijn Koster. "Facing bureaucratic uncertainty in the Bolsa Família Program." Focaal 2019, no. 85 (December 1, 2019): 84–96. http://dx.doi.org/10.3167/fcl.2019.850108.
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Clientelism is often analyzed along lines of moral values and reciprocity or an economic rationality. This article, instead, moves beyond this dichotomy and shows how both frameworks coexist and become entwined. Based on ethnographic research in a city in the Brazilian Northeast, it analyzes how the anti-poverty Bolsa Família Program and its bureaucracy are entangled with electoral politics and clientelism. We show how the program’s beneficiaries engage in clientelist relationships and exchanges to deal with structural precariousness and bureaucratic uncertainty. Contributing to understanding the complexity of clientelism, our analysis demonstrates how they, in their assessment of and dealing with political candidates, employ the frames of reference of both reciprocity and economic rationality in such a way that they act as a “counterpoint” to each other.
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Novák, Lukáš, and Drahomír Novák. "Probabilistic assessment and sensitivity analysis of existing concrete bridge via surrogate modeling." Acta Polytechnica CTU Proceedings 36 (August 18, 2022): 135–41. http://dx.doi.org/10.14311/app.2022.36.0135.
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The paper is focused on probabilistic assessment and sensitivity analysis of existing prestressed concrete bridge using surrogate model in form of Polynomial Chaos Expansion (PCE). The bridge was selected in the framework of the European Project INTERREG AUSTRIA-CZECH REPUBLIC "TCZ190 SAFEBRIDGE" focused on advanced numerical analysis of existing bridges represented by non-linear finite element model. In this study, surrogate model in form of PCE was created, which represents very efficient type of surrogate model. One of significant advantages of PCE is powerful post-processing including sensitivity and moment analysis of the response, which is important part of probabilistic analysis. The obtained numerical results of advanced stochastic analysis consisting of uncertainty quantification and sensitivity analysis of the existing bridge structure are presented in the paper.
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Butterfield, D., and T. Gardiner. "Determining the temporal variability in atmospheric temperature profiles measured using radiosondes and assessment of correction factors for different launch schedules." Atmospheric Measurement Techniques 8, no. 1 (January 29, 2015): 463–70. http://dx.doi.org/10.5194/amt-8-463-2015.
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Abstract. Radiosondes provide one of the primary sources of upper troposphere and stratosphere temperature data for numerical weather prediction, the assessment of long-term trends in atmospheric temperature, study of atmospheric processes and provide intercomparison data for other temperature sensors, e.g. satellites. When intercomparing different temperature profiles it is important to include the effect of temporal mismatch between the measurements. To help quantify this uncertainty the atmospheric temperature variation through the day needs to be assessed, so that a correction and uncertainty for time difference can be calculated. Temperature data from an intensive radiosonde campaign, at Manus Island in Papua New Guinea, were analysed to calculate the hourly rate of change in temperature at different altitudes and provide recommendations and correction factors for different launch schedules. Using these results, three additional longer term data sets were analysed (Lindenberg 1999 to 2008; Lindenberg 2009 to 2012; and Southern Great Plains 2006 to 2012) to assess the diurnal variability of temperature as a function of altitude, time of day and season of the year. This provides the appropriate estimation of temperature differences for given temporal separation and the uncertainty associated with them. A general observation was that 10 or more repeat measurements would be required to get a standard error of the mean of less than 0.1 K per hour of temporal mismatch.
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Teichgräber, Max, and Daniel Straub. "A study on the effects of hidden safety when assessing existing structures." Acta Polytechnica CTU Proceedings 36 (August 18, 2022): 216–23. http://dx.doi.org/10.14311/app.2022.36.0216.
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In many instances, the safety of existing structures can no longer be demonstrated by standard code-based assessments. Reasons for this include changes in the code, changes in the demands on the structures and deterioration. To address this problem, it is common practice to perform a more detailed assessment utilizing advanced models. In this way, many structures can be shown to comply with safety requirements, even if they cannot be verified by standard assessments. The standard code models are often conservatively biased. This leads to designs which include hidden safety. If the reassessment is performed with more advanced models in lieu of standard models, the hidden safety can vanish. Concurrently, the reduced uncertainty of advanced models may compensate this safety reduction. In this paper we investigate this issue on a hypothetical population of existing bridge structures under traffic. We consider that the standard code model is exchanged by an advanced traffic load simulation.
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JILIBERTO, HERRERA RODRIGO. "A HOLARCHICAL MODEL FOR REGIONAL SUSTAINABILITY ASSESSMENT." Journal of Environmental Assessment Policy and Management 06, no. 04 (December 2004): 511–38. http://dx.doi.org/10.1142/s1464333204001833.
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This paper is an attempt to develop a holarchical paradigm for regional sustainability assessment based on a critic of the epistemology of sustainability, seen as between two polar opposites that make up a unified system. On the one hand we find what can be described as a representationalist view, for which sustainability is the result of juxtaposing certain economic, social and environmental aspects of reality. However, complexity and uncertainty are the most relevant epistemological results of trying to define sustainability as an "objective" entity derived from an analytical perspective. On the other hand, complexity and uncertainty lead to the conclusion that sustainability cannot be expressed and, therefore, the problem of what to do does not depend so much on the description of the object we want to act on, but on how we decide what to do. This is the procedural epistemology of sustainability. The methodological and epistemological proposal that has guided the development of the Sustainable Development Strategy for the Region of Murcia, for instance, is equidistant from these two options. It is based on the belief that it is necessary and possible to constitute sustainability as an analytically coherent (i.e. non-arbitrary) object of knowledge, which is at the same time autonomous from the analytical–fragmentary descriptions that comprise standard scientific knowledge. In the centre of this epistemology is a systemic understanding of "reality" that tries to grasp the hierarchical inter-existence of the outer world, and focuses primarily on contingent management from a dynamic viewpoint rather than that of certainty. This epistemological dual perspective has many implications for evaluation practice, both in the framing of technical analysis, and in the management of social participation.
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Moore, R. H., V. A. Karydis, S. L. Capps, T. L. Lathem, and A. Nenes. "Droplet number uncertainties associated with CCN: an assessment using observations and a global model adjoint." Atmospheric Chemistry and Physics 13, no. 8 (April 24, 2013): 4235–51. http://dx.doi.org/10.5194/acp-13-4235-2013.
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Abstract. We use the Global Modelling Initiative (GMI) chemical transport model with a cloud droplet parameterisation adjoint to quantify the sensitivity of cloud droplet number concentration to uncertainties in predicting CCN concentrations. Published CCN closure uncertainties for six different sets of simplifying compositional and mixing state assumptions are used as proxies for modelled CCN uncertainty arising from application of those scenarios. It is found that cloud droplet number concentrations (Nd) are fairly insensitive to the number concentration (Na) of aerosol which act as CCN over the continents (∂lnNd/∂lnNa ~10–30%), but the sensitivities exceed 70% in pristine regions such as the Alaskan Arctic and remote oceans. This means that CCN concentration uncertainties of 4–71% translate into only 1–23% uncertainty in cloud droplet number, on average. Since most of the anthropogenic indirect forcing is concentrated over the continents, this work shows that the application of Köhler theory and attendant simplifying assumptions in models is not a major source of uncertainty in predicting cloud droplet number or anthropogenic aerosol indirect forcing for the liquid, stratiform clouds simulated in these models. However, it does highlight the sensitivity of some remote areas to pollution brought into the region via long-range transport (e.g., biomass burning) or from seasonal biogenic sources (e.g., phytoplankton as a source of dimethylsulfide in the southern oceans). Since these transient processes are not captured well by the climatological emissions inventories employed by current large-scale models, the uncertainties in aerosol-cloud interactions during these events could be much larger than those uncovered here. This finding motivates additional measurements in these pristine regions, for which few observations exist, to quantify the impact (and associated uncertainty) of transient aerosol processes on cloud properties.
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Tutino, Stefania. "Early Modern Uncertainty: Reason, Conscience, and Belief in Post-Reformation Catholicism." Religions 13, no. 11 (November 16, 2022): 1108. http://dx.doi.org/10.3390/rel13111108.
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This essay investigates the role of uncertainty in post-Reformation Catholicism. It argues that one of the reasons why uncertainty was so central to early modern Catholic discourse lies in the complex and multifaced relationship between believing—that is, the act of holding as true something that we are unable to verify as such by means of reason—and knowing—that is, the act of holding something as true on the basis of a reasonable and reasoned assessment. By providing a brief analysis of printed and manuscript sources, this essays shows how some of the theological, religious, and intellectual tensions in articulating the relationship between things that need to be believed by faith and things that need to be known by reason, both in the works of influential theologians such as Augustine and Francisco Suárez, and in the elaboration of a wider sector of the Catholic population.
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Pinceratto, E. "THE CHALLENGES OF ENVIRONMENTAL MANAGEMENT IN 2003—A REVIEW OF REGULATORY, SUSTAINABILITY, AND MULTIPLE STAKEHOLDER INTEREST ISSUES." APPEA Journal 43, no. 2 (2003): 121. http://dx.doi.org/10.1071/aj02069.
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Following the uncertainty created by the introduction of the EPBC Act in 2000, a new regime of public environmental assessment of petroleum projects was successfully established by the regulatory agencies and the petroleum industry.Sustainability of developments, multiple stakeholder interests and meaningful consultations, are the current challenges in accessing new areas for exploration and development.
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Venkat Ratnam, M., N. Pravallika, S. Ravindra Babu, G. Basha, M. Pramitha, and B. V. Krishna Murthy. "Assessment of GPS radiosonde descent data." Atmospheric Measurement Techniques 7, no. 4 (April 16, 2014): 1011–25. http://dx.doi.org/10.5194/amt-7-1011-2014.
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Abstract. Radiosondes are widely used to obtain basic meteorological parameters such as pressure (P), temperature (T), relative humidity (RH) and horizontal winds during the balloon ascent up to the altitude of balloon burst, usually ~ 32–35 km. Data from the radiosondes released from Gadanki (13.5° N, 79.2° E), a tropical station in India, have been collected during the ascent and during the descent as well without attaching any parachute or its equivalent since the year 2008. In the present study an attempt has been made to characterize the radiosonde descent data with the main objective of exploring its usefulness and reliability for scientific purposes. We compared the data obtained during ascent and descent phases of the same sounding. The mean differences in T, RH and horizontal winds between ascent and descent data are found to be small and are sometimes even within the uncertainty of the measurements and/or expected diurnal variation itself. The very good consistency observed between the ascent and the descent data shows that one more profile of the meteorological parameters can be constructed within 3 h of time of balloon launch practically at no additional cost. Further checks are done by utilizing the 3-hourly radiosonde observations collected during the Tropical Tropopause Dynamics campaigns conducted at Gadanki. In the process of checking the consistency between the radiosonde ascent and descent data, several new findings are arrived at and are reported in this study. In general, it has taken more than half an hour for the balloon to reach the ground from the burst altitude. It is also observed that the fall velocity is close to 10 m s−1 near the surface. Finally, it is suggested to record the observations also when the balloon is descending as this information is useful for scientific purposes.
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Dunne, Erin, Ian E. Galbally, Min Cheng, Paul Selleck, Suzie B. Molloy, and Sarah J. Lawson. "Comparison of VOC measurements made by PTR-MS, adsorbent tubes–GC-FID-MS and DNPH derivatization–HPLC during the Sydney Particle Study, 2012: a contribution to the assessment of uncertainty in routine atmospheric VOC measurements." Atmospheric Measurement Techniques 11, no. 1 (January 10, 2018): 141–59. http://dx.doi.org/10.5194/amt-11-141-2018.
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Abstract. Understanding uncertainty is essential for utilizing atmospheric volatile organic compound (VOC) measurements in robust ways to develop atmospheric science. This study describes an inter-comparison of the VOC data, and the derived uncertainty estimates, measured with three independent techniques (PTR-MS, proton-transfer-reaction mass spectrometry; GC-FID-MS, gas chromatography with flame-ionization and mass spectrometric detection; and DNPH–HPLC, 2,4-dinitrophenylhydrazine derivatization followed by analysis by high-performance liquid chromatography) during routine monitoring as part of the Sydney Particle Study (SPS) campaign in 2012. Benzene, toluene, C8 aromatics, isoprene, formaldehyde and acetaldehyde were selected for the comparison, based on objective selection criteria from the available data. Bottom-up uncertainty analyses were undertaken for each compound and each measurement system. Top-down uncertainties were quantified via the inter-comparisons. In all seven comparisons, the correlations between independent measurement techniques were high with R2 values with a median of 0.92 (range 0.75–0.98) and small root mean square of the deviations (RMSD) of the observations from the regression line with a median of 0.11 (range 0.04–0.23 ppbv). These results give a high degree of confidence that for each comparison the response of the two independent techniques is dominated by the same constituents. The slope and intercept as determined by reduced major axis (RMA) regression gives a different story. The slopes varied considerably with a median of 1.25 and a range of 1.16–2.01. The intercepts varied with a median of 0.04 and a range of −0.03 to 0.31 ppbv. An ideal comparison would give a slope of 1.00 and an intercept of 0. Some sources of uncertainty that are poorly quantified by the bottom-up uncertainty analysis method were identified, including: contributions of non-target compounds to the measurement of the target compound for benzene, toluene and isoprene by PTR-MS as well as the under-reporting of formaldehyde, acetaldehyde and acetone by the DNPH technique. As well as these, this study has identified a specific interference of liquid water with acetone measurements by the DNPH technique. These relationships reported for Sydney 2012 were incorporated into a larger analysis with 61 similar published inter-comparison studies for the same compounds. Overall, for the light aromatics, isoprene and the C1–C3 carbonyls, the uncertainty in a set of measurements varies by a factor of between 1.5 and 2. These uncertainties (∼50 %) are significantly higher than uncertainties estimated using standard propagation of error methods, which in this case were ∼22 % or less, and are the result of the presence of poorly understood or neglected processes that affect the measurement and its uncertainty. The uncertainties in VOC measurements identified here should be considered when assessing the reliability of VOC measurements from routine monitoring with individual, stand-alone instruments; when utilizing VOC data to constrain and inform air quality and climate models; when using VOC observations for human exposure studies; and for comparison with satellite retrievals.
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Fragkos, Konstantinos, Bogdan Antonescu, David M. Giles, Dragoş Ene, Mihai Boldeanu, Georgios A. Efstathiou, Livio Belegante, and Doina Nicolae. "Assessment of the total precipitable water from a sun photometer, microwave radiometer and radiosondes at a continental site in southeastern Europe." Atmospheric Measurement Techniques 12, no. 3 (March 29, 2019): 1979–97. http://dx.doi.org/10.5194/amt-12-1979-2019.
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Abstract. In this study, we discuss the differences in the total precipitable water (TPW), retrieved from a Cimel sun photometer operating at a continental site in southeast Europe, between version 3 (V3) and version 2 (V2) of the AErosol RObotic NETwork (AERONET) algorithms. In addition, we evaluate the performance of the two algorithms comparing their product with the TPW obtained from a collocated microwave radiometer and nearby radiosondes during the period 2007–2017. The TPW from all three instruments was highly correlated, showing the same annual cycle, with lower values during winter and higher values during summer. The sun photometer and the microwave radiometer depict the same daily cycle, with some discrepancies during early morning and late afternoon due to the effect of solar zenith angle on the measurements of the photometer. The TPW from V3 of the AERONET algorithm has small differences compared with V2, mostly related to the use of the new laboratory-based temperature coefficients used in V3. The microwave radiometer measurements are in good agreement with those obtained by the radiosonde, especially during night-time when the differences between the two instruments are almost negligible. The comparison of the sun photometer data with high-quality independent measurements from radiosondes and the radiometer shows that the absolute differences between V3 and the other two datasets are slightly higher compared with V2. However, V3 has a lower dependence from the TPW and the internal sensor temperature, indicating a better performance of the retrieving algorithm. The calculated one-sigma uncertainty for V3 as estimated, from the comparison with the radiosondes, is about 10 %, which is in accordance with previous studies for the estimation of uncertainty for V2. This uncertainty is further reduced to about 6 % when AERONET V3 is compared with the collocated microwave radiometer. To our knowledge, this is the first in-depth analysis of the V3 TPW, and although the findings presented here are for a specific site, we believe that they are representative of other mid-latitude continental stations.
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Arosio, Carlo, Alexei Rozanov, Victor Gorshelev, Alexandra Laeng, and John P. Burrows. "Assessment of the error budget for stratospheric ozone profiles retrieved from OMPS limb scatter measurements." Atmospheric Measurement Techniques 15, no. 20 (October 20, 2022): 5949–67. http://dx.doi.org/10.5194/amt-15-5949-2022.
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Abstract. This study presents an error budget assessment for the ozone profiles retrieved at the University of Bremen through limb observations of the Ozone Mapper and Profiler Suite – Limb Profiler Suomi National Polar-orbiting Partnership (OMPS-LP SNPP) satellite instrument. The error characteristics are presented in a form that aims at being compliant with the recommendations and the standardizing effort of the Towards Unified Error Reporting (TUNER) project. Besides the retrieval noise, contributions from retrieval parameters are extensively discussed and quantified by using synthetic retrievals performed with the SCIATRAN radiative transfer model. For this investigation, a representative set of OMPS-LP measurements is selected to provide a reliable estimation of the uncertainties as a function of latitude and season. Errors originating from model approximations and spectroscopic data are also taken into account and found to be non-negligible. The choice of the ozone cross section is found to be relevant, as expected. Overall, we classify the estimated errors as random or systematic and investigate correlations between errors from different sources. After summing up the relevant error components, we present an estimate of the total random uncertainty on the retrieved ozone profiles, which is found to be in the 5 %–30 % range in the lower stratosphere, 3 %–5 % in the middle stratosphere, and 5 %–7 % at upper altitudes. The systematic uncertainty is mainly due to cloud contamination and model errors in the lower stratosphere and due to the retrieval bias at higher altitudes. The corresponding total bias exceeds 5 % only above 50 km and below 20 km. After computing the estimate of the overall random and systematic error components, we also provide an ex-post assessment of the uncertainties using self-collocated OMPS-LP observations and collocated Microwave Limb Sounder (MLS) data in a χ2 fashion.
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Hans, Imke, Martin Burgdorf, Viju O. John, Jonathan Mittaz, and Stefan A. Buehler. "Noise performance of microwave humidity sounders over their lifetime." Atmospheric Measurement Techniques 10, no. 12 (December 18, 2017): 4927–45. http://dx.doi.org/10.5194/amt-10-4927-2017.
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Abstract. The microwave humidity sounders Special Sensor Microwave Water Vapor Profiler (SSMT-2), Advanced Microwave Sounding Unit-B (AMSU-B) and Microwave Humidity Sounder (MHS) to date have been providing data records for 25 years. So far, the data records lack uncertainty information essential for constructing consistent long time data series. In this study, we assess the quality of the recorded data with respect to the uncertainty caused by noise. We calculate the noise on the raw calibration counts from the deep space views (DSVs) of the instrument and the noise equivalent differential temperature (NEΔT) as a measure for the radiometer sensitivity. For this purpose, we use the Allan deviation that is not biased from an underlying varying mean of the data and that has been suggested only recently for application in atmospheric remote sensing. Moreover, we use the bias function related to the Allan deviation to infer the underlying spectrum of the noise. As examples, we investigate the noise spectrum in flight for some instruments. For the assessment of the noise evolution in time, we provide a descriptive and graphical overview of the calculated NEΔT over the life span of each instrument and channel. This overview can serve as an easily accessible information for users interested in the noise performance of a specific instrument, channel and time. Within the time evolution of the noise, we identify periods of instrumental degradation, which manifest themselves in an increasing NEΔT, and periods of erratic behaviour, which show sudden increases of NEΔT interrupting the overall smooth evolution of the noise. From this assessment and subsequent exclusion of the aforementioned periods, we present a chart showing available data records with NEΔT < 1 K. Due to overlapping life spans of the instruments, these reduced data records still cover without gaps the time since 1994 and may therefore serve as a first step for constructing long time series. Our method for count noise estimation, that has been used in this study, will be used in the data processing to provide input values for the uncertainty propagation in the generation of a new set of Fundamental Climate Data Records (FCDRs) that are currently produced in the project Fidelity and Uncertainty in Climate data records from Earth Observation (FIDUCEO).
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Harvey, Pamela D. "Educated Guesses: Health Risk Assessment in Environmental Impact Statements." American Journal of Law & Medicine 16, no. 3 (1990): 399–427. http://dx.doi.org/10.1017/s0098858800008625.
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Environmental pollution threatens public health. The search for solutions has advanced the frontiers of science and law. Efforts to protect the environment and public health begin with describing potential adverse consequences of human activities and characterizing the predicted risk. The National Environmental Policy Act requires the preparation of environmental impact statements to describe the effects of proposed federal projects and provide information for agency decisionmakers and the public.Risks to public health are particularly difficult to quantify because of uncertainty about the relation between exposure to environmental contamination and disease. Risk assessment is the current scientific tool to present estimates of risk. The methodology has created controversy, however, when underlying assumptions and uncertainties are not clearly presented. Critics caution that the methodology is vulnerable to bias. This Note evaluates the use of risk assessment in the environmental impact statement process and offers recommendations to ensure informed decisions.
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Viero, Daniele P. "Comment on “Can assimilation of crowdsourced data in hydrological modelling improve flood prediction?” by Mazzoleni et al. (2017)." Hydrology and Earth System Sciences 22, no. 1 (January 10, 2018): 171–77. http://dx.doi.org/10.5194/hess-22-171-2018.
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Abstract. Citizen science and crowdsourcing are gaining increasing attention among hydrologists. In a recent contribution, Mazzoleni et al. (2017) investigated the integration of crowdsourced data (CSD) into hydrological models to improve the accuracy of real-time flood forecasts. The authors used synthetic CSD (i.e. not actually measured), because real CSD were not available at the time of the study. In their work, which is a proof-of-concept study, Mazzoleni et al. (2017) showed that assimilation of CSD improves the overall model performance; the impact of irregular frequency of available CSD, and that of data uncertainty, were also deeply assessed. However, the use of synthetic CSD in conjunction with (semi-)distributed hydrological models deserves further discussion. As a result of equifinality, poor model identifiability, and deficiencies in model structure, internal states of (semi-)distributed models can hardly mimic the actual states of complex systems away from calibration points. Accordingly, the use of synthetic CSD that are drawn from model internal states under best-fit conditions can lead to overestimation of the effectiveness of CSD assimilation in improving flood prediction. Operational flood forecasting, which results in decisions of high societal value, requires robust knowledge of the model behaviour and an in-depth assessment of both model structure and forcing data. Additional guidelines are given that are useful for the a priori evaluation of CSD for real-time flood forecasting and, hopefully, for planning apt design strategies for both model calibration and collection of CSD.
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Choukulkar, Aditya, W. Alan Brewer, Scott P. Sandberg, Ann Weickmann, Timothy A. Bonin, R. Michael Hardesty, Julie K. Lundquist, et al. "Evaluation of single and multiple Doppler lidar techniques to measure complex flow during the XPIA field campaign." Atmospheric Measurement Techniques 10, no. 1 (January 23, 2017): 247–64. http://dx.doi.org/10.5194/amt-10-247-2017.
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Abstract. Accurate three-dimensional information of wind flow fields can be an important tool in not only visualizing complex flow but also understanding the underlying physical processes and improving flow modeling. However, a thorough analysis of the measurement uncertainties is required to properly interpret results. The XPIA (eXperimental Planetary boundary layer Instrumentation Assessment) field campaign conducted at the Boulder Atmospheric Observatory (BAO) in Erie, CO, from 2 March to 31 May 2015 brought together a large suite of in situ and remote sensing measurement platforms to evaluate complex flow measurement strategies. In this paper, measurement uncertainties for different single and multi-Doppler strategies using simple scan geometries (conical, vertical plane and staring) are investigated. The tradeoffs (such as time–space resolution vs. spatial coverage) among the different measurement techniques are evaluated using co-located measurements made near the BAO tower. Sensitivity of the single-/multi-Doppler measurement uncertainties to averaging period are investigated using the sonic anemometers installed on the BAO tower as the standard reference. Finally, the radiometer measurements are used to partition the measurement periods as a function of atmospheric stability to determine their effect on measurement uncertainty. It was found that with an increase in spatial coverage and measurement complexity, the uncertainty in the wind measurement also increased. For multi-Doppler techniques, the increase in uncertainty for temporally uncoordinated measurements is possibly due to requiring additional assumptions of stationarity along with horizontal homogeneity and less representative line-of-sight velocity statistics. It was also found that wind speed measurement uncertainty was lower during stable conditions compared to unstable conditions.
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Minbiole, Julie. "Improving Course Coherence & Assessment Rigor: “Understanding by Design” in a Nonmajors Biology Course." American Biology Teacher 78, no. 6 (August 1, 2016): 463–70. http://dx.doi.org/10.1525/abt.2016.78.6.463.
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Instructors in two- and four-year undergraduate institutions face a variety of challenges in designing and delivering high-quality courses for their students and in creating accurate assessments of student learning. Traditional course planning (a linear, start-to-finish process based on the knowledge and perspective of the instructor) can lead to lack of clarity of learning objectives for students, uncertainty about course priorities for both instructor and students, and poor alignment between course material and assessments. To address these issues, Understanding by Design (UbD), a course-planning protocol widely used in K–12 education, was implemented to redesign a one-semester, nonmajors “Sensation & Perception” course at a four-year liberal arts college. This implementation improved the instructor's understanding of desired student learning outcomes, allowed core concepts and science competencies to be prioritized as recommended by the “Vision and Change” reform initiative, and led to decreased lecture time in favor of greater lab and student-driven discussion time. In addition, this process allowed components of evidence-based reasoning and scientific process to be incorporated authentically into assessments. Despite the increasing rigor of assessments, there was a statistically significant increase in students earning an A or B on the final exam after UbD implementation.
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FREITAS, GABRIEL VILELA RESENDE. "Narrative Economics and Behavioral Economics: contributions to the behavioral insights on post-Keynesian theory." Brazilian Journal of Political Economy 41, no. 2 (April 2021): 372–84. http://dx.doi.org/10.1590/0101-31572021-3191.
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ABSTRACT The objective of this review is to discuss the formation of knowledge proposed by Keynes on his Treatise on Probability, and the economic agents’ behavior in an uncertainty scenario presented on his General Theory, by the Narrative Economics’ and Behavioral Economics perspectives. The hypothesis that will be analyzed is that in a keynesian uncertainty scenario, economic agents tend to act according to their context (social, geographic, historic, cultural) spreading narratives by which they identify themselves and orient decisions that cause sensible movements on the economic aggregates. Revisiting the literature, we could conclude that by bringing together the behavioral economy and the narrative economy theory, we could, from the Keynes’ insights on his writings, perceive strong empirical evidence that can be analytically important on the assessment of the economic fluctuations.
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Giri, Upendra Kumar, and Anirudh Pradhan. "Inherent uncertainty involved in six-dimensional shift determination in ExacTrac imaging system." Journal of Radiotherapy in Practice 16, no. 4 (May 9, 2017): 409–14. http://dx.doi.org/10.1017/s1460396917000280.
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AbstractObjectiveThis study was conducted for the assessment of in-built systematic and random errors in the ExacTrac imaging system due to the software of Brainlab, on that basis; recommending a new quality control programme for ExacTrac imaging system.MethodsA program was developed to compare the image dataset of real time anthropomorphic pelvic phantom using ExacTrac with the reference image dataset from computed tomography. Images were acquired 20 times in a day, on single sitting for 20 conjugative days. On the basic of these translational and rotational shifts, systematic and random errors were calculated that had arisen due to multiple time image acquisition and image registration between acquired and reference image dataset of the phantom.ResultsRandom errors were found as 0·006 cm in right-left (Rt-Lt) direction, 0·008 cm in superior-inferior (Sup-Inf) direction and 0·012 cm in anterior-posterior (Ant-Post) direction. On this basic, margins were calculated using Van Herk formula; it was found that there were 0·02 cm inherent shift in Rt-Lt direction, 0·03 cm in Sup-Inf direction and 0·03 cm in Ant-Post direction.ConclusionThis study concluded that there was inherent error in ExacTrac system which can be quantified and used as a quality assurance tool for the ExacTrac system.
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Metsch, Rutger, and Rémy Gerbay. "Prospect Theory and due process paranoia: what behavioural models say about arbitrators’ assessment of risk and uncertainty." Arbitration International 36, no. 2 (June 1, 2020): 233–52. http://dx.doi.org/10.1093/arbint/aiaa017.
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Abstract The term ‘due process paranoia’ is used to describe a perceived reluctance by arbitral tribunals to act decisively in certain situations for fear of the arbitral award being challenged on the basis of a party not having had the chance to present its case fully. This article approaches due process paranoia from the perspective of Prospect Theory, which is a behavioural model describing how individuals make decisions under risk and uncertainty. The authors examine how Prospect Theory’s insight that decision makers tend to overweight low-probability events in their decision-making (the ‘possibility effect’) affects decision-making by arbitrators when faced with the threat of challenge to their awards on due process grounds (the ‘enforcement risk’). The article concludes that the possibility effect is prone to contribute to an overweighting by arbitrators of the enforcement risk, thereby explaining the perceived tendency by tribunals to make sub-optimal decisions when faced with due process-related complaints or threats.
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Schwarz, J. P., S. J. Doherty, F. Li, S. T. Ruggiero, C. E. Tanner, A. E. Perring, R. S. Gao, and D. W. Fahey. "Assessing Single Particle Soot Photometer and Integrating Sphere/Integrating Sandwich Spectrophotometer measurement techniques for quantifying black carbon concentration in snow." Atmospheric Measurement Techniques 5, no. 11 (November 1, 2012): 2581–92. http://dx.doi.org/10.5194/amt-5-2581-2012.
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Abstract. We evaluate the performance of the Single Particle Soot Photometer (SP2) and the Integrating Sphere/Integrating Sandwich Spectrophotometer (ISSW) in quantifying the concentration of refractory black carbon (BC) in snow samples. We find that the SP2 can be used to measure BC mass concentration in snow with substantially larger uncertainty (60%) than for atmospheric sampling (<30%). Achieving this level of accuracy requires careful assessment of nebulizer performance and SP2 calibration with consideration of the fact that BC in snow can exist in larger sizes than typically observed in the atmosphere. Once these issues are addressed, the SP2 is able to measure the size distribution and mass concentration of BC in the snow. Laboratory comparison of the SP2 and the ISSW revealed significant biases in the estimate of BC concentration from the ISSW when test samples contained dust or non-absorbing particulates. These results suggest that current estimates of BC mass concentration in snow or ice formed from fallen snow using either the SP2 or the ISSW may be associated with significant underestimates of uncertainty.
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Linn, Robert L. "Performance Standards': Utility for Different Uses of Assessments." education policy analysis archives 11 (September 1, 2003): 31. http://dx.doi.org/10.14507/epaa.v11n31.2003.
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Performance standards are arguably one of the most controversial topics in educational measurement. There are uses of assessments such as licensure and certification where performance standards are essential. There are many other uses, however, where performance standards have been mandated or become the preferred method of reporting assessment results where the standards are not essential to the use. Distinctions between essential and nonessential uses of performance standards are discussed. It is argued that the insistence on reporting in terms of performance standards in situations where they are not essential has been more harmful than helpful. Variability in the definitions of proficient academic achievement by states for purposes of the No Child Left Behind Act of 2001 is discussed and it is argued that the variability is so great that characterizing achievement is meaningless. Illustrations of the great uncertainty in standards are provided.
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Kim, Sungwon. "Development and Validation of a Scale for Christian Character Assessment for Young Children1." Religions 10, no. 5 (May 13, 2019): 318. http://dx.doi.org/10.3390/rel10050318.
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The emphasis on character education that has emerged from the Nuri national curriculum and the Character Education Act is leading the direction of Korean education. However, the lack of a proper scale of character assessment—especially Christian character for young children—has caused uncertainty in related studies. This study aims to develop and validate a scale that assesses Christian character for young children. The data was collected from 257 (study 1) and 405 (study 2) Christian children who attend church and kindergarten or day care center. Within 12 factors, 67 questions were developed, which were subsequently refined to 39 questions by seven professors. The Christian character scale for young children was finalized to twenty-four questions through exploratory factor analysis and confirmatory factor analysis within four factors: piety, self-control/harmony, responsibility/independence, and caring/respect.
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Dorman, David C., Melvin E. Andersen, Jerry M. Roper, and Michael D. Taylor. "Update on a Pharmacokinetic-Centric Alternative Tier II Program for MMT—Part I: Program Implementation and Lessons Learned." Journal of Toxicology 2012 (2012): 1–10. http://dx.doi.org/10.1155/2012/946742.
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Concerns have been raised regarding environmental manganese exposure since high exposures have been associated with neurological disorders. The USA Environmental Protection Agency most recent human health risk assessment of inhaled manganese conducted in 1993 identified specific areas of uncertainty regarding manganese pharmacokinetics. This led to the development of a test rule under the USA Clean Air Act that required the generation of pharmacokinetic information on the inorganic manganese combustion products of the organometallic fuel additive methylcyclopentadienyl manganese tricarbonyl (MMT). The Alternative Tier 2 testing program for MMT, described in this paper, has yielded substantial pharmacokinetic data and has enabled the generation of physiologically based pharmacokinetic (PBPK) models for manganese. These models are capable of predicting tissue manganese concentrations across a variety of dose routes, levels, and durations while accounting for factors such as age, gender, and reproductive status, enabling the consideration of tissue dosimetry in future risk assessments.
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Immler, F. J., J. Dykema, T. Gardiner, D. N. Whiteman, P. W. Thorne, and H. Vömel. "Reference Quality Upper-Air Measurements: guidance for developing GRUAN data products." Atmospheric Measurement Techniques 3, no. 5 (September 9, 2010): 1217–31. http://dx.doi.org/10.5194/amt-3-1217-2010.
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Abstract. The accurate monitoring of climate change imposes strict requirements upon observing systems, in particular regarding measurement accuracy and long-term stability. Currently available data records of the essential climate variables (temperature-T, geopotential-p, humidity-RH, wind, and cloud properties) in the upper-air generally fail to fulfil such requirements. This raises serious issues about the ability to detect, quantify and understand recent climate changes and their causes. GCOS is currently implementing a Reference Upper-Air Network (GRUAN) in order to fill this major void within the global observing system. As part of the GRUAN implementation plan we provide herein fundamental guidelines for establishing and maintaining reference quality atmospheric observations which are based on principal concepts of metrology, in particular traceability. It is argued that the detailed analysis of the uncertainty budget of a measurement technique is the critical step for achieving this goal. As we will demonstrate with an example, detailed knowledge of the calibration procedures and data processing algorithms are required for determining the uncertainty of each individual data point. Of particular importance is the careful assessment of the uncertainties introduced by correction schemes adjusting for systematic effects.
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Perlingeiro, Rogério Moreno, Mayra Soares Pereira Lima Perlingeiro, Christine Kowal Chinelli, Elaine Garrido Vazquez, Eduardo Linhares Qualharini, Assed N. Haddad, Ahmed W. A. Hammad, and Carlos Alberto Pereira Soares. "Sustainable Assessment of Public Works through a Multi-Criteria Framework." Sustainability 12, no. 17 (August 25, 2020): 6896. http://dx.doi.org/10.3390/su12176896.
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Enhancing the sustainability of public works has been a key agenda in recent years for many governmental organizations. Public works contribute significantly to a large portion of engineering works and have great potential to impact the sustainability of cities. Thus, evaluating the sustainability of these projects is highly relevant, mainly regarding their impacts on environmental, social, and economic aspects. There are currently assessment systems and methods with different scopes and approaches. Yet, there remains uncertainty when it comes to considering public works’ sustainability and how useful criteria can be incorporated into the proposed assessment tasks to ensure such a goal. This study contributes to filling this gap by developing, through an extensive and detailed bibliographic research, a flexible and comprehensive framework composed of 214 criteria distributed across nine categories that measure the degree of sustainability of public works, with emphasis on economic, social and environmental goals. The proposed framework can act as a practical tool, functioning as a checklist applicable to all types of public construction works, and at any stage of the lifecycle. Evaluation of the framework by professionals indicated its suitability when encompassing sustainability objectives, its viability, and its ease of use.
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Сатторов and F. Sattorov. "Methods of indistinct multicriteria decision support in network planning." Forestry Engineering Journal 4, no. 2 (June 10, 2014): 0. http://dx.doi.org/10.12737/4534.
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In this paper we consider the solution of multicriteria decision support in the assessment of the time parameter of network plan under uncertainty fuzzy character. Proposed method is based on the mechanisms of fuzzy set theory and multicriteria optimization and represents a fuzzy model, as input parameters of which set of fuzzy criterion act, the calculation in a fuzzy model is carried out on the bases of fuzzy reasoning (logical implication) of the base of rules, and as an output parameter of model, ie, possibilistic duration of work acts as the resulting function.
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Jackson, Robert, Scott Collis, Valentin Louf, Alain Protat, Die Wang, Scott Giangrande, Elizabeth J. Thompson, Brenda Dolan, and Scott W. Powell. "The development of rainfall retrievals from radar at Darwin." Atmospheric Measurement Techniques 14, no. 1 (January 4, 2021): 53–69. http://dx.doi.org/10.5194/amt-14-53-2021.
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Abstract. The U.S. Department of Energy Atmospheric Radiation Measurement program Tropical Western Pacific site hosted a C-band polarization (CPOL) radar in Darwin, Australia. It provides 2 decades of tropical rainfall characteristics useful for validating global circulation models. Rainfall retrievals from radar assume characteristics about the droplet size distribution (DSD) that vary significantly. To minimize the uncertainty associated with DSD variability, new radar rainfall techniques use dual polarization and specific attenuation estimates. This study challenges the applicability of several specific attenuation and dual-polarization-based rainfall estimators in tropical settings using a 4-year archive of Darwin disdrometer datasets in conjunction with CPOL observations. This assessment is based on three metrics: statistical uncertainty estimates, principal component analysis (PCA), and comparisons of various retrievals from CPOL data. The PCA shows that the variability in R can be consistently attributed to reflectivity, but dependence on dual-polarization quantities was wavelength dependent for 1<R<10mmh-1. These rates primarily originate from stratiform clouds and weak convection (median drop diameters less than 1.5 mm). The dual-polarization specific differential phase and differential reflectivity increase in usefulness for rainfall estimators in times with R>10mmh-1. Rainfall estimates during these conditions primarily originate from deep convective clouds with median drop diameters greater than 1.5 mm. An uncertainty analysis and intercomparison with CPOL show that a Colorado State University blended technique for tropical oceans, with modified estimators developed from video disdrometer observations, is most appropriate for use in all cases, such as when 1<R<10mmh-1 (stratiform rain) and when R>10mmh-1 (deeper convective rain).
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Salter, Alexander William, and Vlad Tarko. "Governing the banking system: an assessment of resilience based on Elinor Ostrom's design principles." Journal of Institutional Economics 15, no. 3 (November 19, 2018): 505–19. http://dx.doi.org/10.1017/s1744137418000401.
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AbstractThe problem of financial stability is political and institutional, rather than narrowly economic. To achieve a more resilient financial system, we need to pay attention to the incentives of actors who have the power to act discretionarily, and to the knowledge limitations of such actors in the face of substantial complexity and uncertainty. The literature on polycentric governance and institutional resilience provides key insights that the literature on financial stability has thus far neglected. We offer an analysis based on the “design principles” for robust governance institutions proposed by Nobel laureate Elinor Ostrom. We apply these principles to banking systems and explore under what conditions a banking system can be expected to discover rules that align private incentives with broader financial stability, and generate the necessary knowledge to govern such a complex system. This perspective challenges both “microprudential” and “macroprudential” approaches, which assume a monocentric financial and banking regulator.
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Söder, Jens, Michael Gerding, Andreas Schneider, Andreas Dörnbrack, Henrike Wilms, Johannes Wagner, and Franz-Josef Lübken. "Evaluation of wake influence on high-resolution balloon-sonde measurements." Atmospheric Measurement Techniques 12, no. 8 (August 2, 2019): 4191–210. http://dx.doi.org/10.5194/amt-12-4191-2019.
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Abstract. Balloons are used for various in situ measurements in the atmosphere. On turbulence measurements from rising balloons there is a potential for misinterpreting wake-created fluctuations in the trail of the balloon for atmospheric turbulence. These wake effects have an influence on temperature and humidity measurements from radiosondes as well. The primary aim of this study is to assess the likelihood for wake encounter on the payload below a rising balloon. Therefore, we present a tool for calculating this probability based on radiosonde wind data. This includes a retrieval of vertical winds from the radiosonde and an uncertainty analysis of the wake assessment. Our wake evaluation tool may be used for any balloon–gondola distance and provides a significant refinement compared to existing assessments. We have analysed wake effects for various balloon–gondola distances applying atmospheric background conditions from a set of 30 radiosondes. For a standard radiosonde we find an average probability for wake encounter of 28 %, pointing out the importance of estimating wake effects on sounding balloons. Furthermore, we find that even millimetre-sized objects in the payload can have significant effects on high-resolution turbulence measurements, if they are located upstream of the turbulence sensor.
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Babovic, Filip, and Ana Mijic. "Economic Evaluation of Adaptation Pathways for an Urban Drainage System Experiencing Deep Uncertainty." Water 11, no. 3 (March 14, 2019): 531. http://dx.doi.org/10.3390/w11030531.
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As Decision Making under Deep Uncertainty methodologies are becoming more widely utilised, there has been a growth in the use and generation of Adaptation Pathways. These are meant to convey to policy makers how short-term adaptations can act as elements of longer-term adaptation strategies. However, sets of Adaptation Pathways do not convey the individual pathway’s relative costs and benefits. To address this problem in relation to urban pluvial flooding, an economic analysis of a set of Adaptation Pathways was conducted. Initially, a methodology to conduct an economic assessment for deterministic climate change scenarios is developed. This methodology is then modified, using methods that underpin real options to assess how a pathway performs across a bundle of possible futures. This delivered information on how the performance of adaptations can vary across different climate change scenarios. By comparing the deterministic analysis to the new method, it was found that the order in which options are implemented greatly affects the financial performance of an Adaptation Pathway, even if the final combination of options is identical. The presented methodology has the potential to greatly improve decision making by informing policy makers on the potential performance of adaptation strategies being considered.
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Sperlich, Peter, Gordon W. Brailsford, Rowena C. Moss, John McGregor, Ross J. Martin, Sylvia Nichol, Sara Mikaloff-Fletcher, et al. "IRIS analyser assessment reveals sub-hourly variability of isotope ratios in carbon dioxide at Baring Head, New Zealand's atmospheric observatory in the Southern Ocean." Atmospheric Measurement Techniques 15, no. 6 (March 21, 2022): 1631–56. http://dx.doi.org/10.5194/amt-15-1631-2022.
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Abstract. We assess the performance of an isotope ratio infrared spectrometer (IRIS) to measure carbon (δ13C) and oxygen (δ18O) isotope ratios in atmospheric carbon dioxide (CO2) and report observations from a 26 d field deployment trial at Baring Head, New Zealand, NIWA's atmospheric observatory for Southern Ocean baseline air. Our study describes an operational method to improve the performance in comparison to previous publications on this analytical instrument. By using a calibration technique that reflected the principle of identical treatment of sample and reference gases, we achieved a reproducibility of 0.07 ‰ for δ13C-CO2 and 0.06 ‰ for δ18O-CO2 over multiple days. This performance is within the extended compatibility goal of 0.1 ‰ for both δ13C-CO2 and δ18O-CO2, which was recommended by the World Meteorological Organization (WMO). Further improvement in measurement performance is desirable to also meet the WMO network compatibility goals of 0.01 ‰ for δ13C-CO2 and 0.05 ‰ for δ18O-CO2, which is needed to resolve the small variability that is typical for background air observatories such as Baring Head. One objective of this study was to assess the capabilities and limitations of the IRIS analyser to resolve δ13C-CO2 and δ18O-CO2 variations under field conditions. Therefore, we selected multiple events within the 26 d record for Keeling plot analysis. This resolved the isotopic composition of endmembers with an uncertainty of ≤ 1 ‰ when the magnitude of CO2 signals is larger than 10 ppm. The uncertainty of the Keeling plot analysis strongly increased for smaller CO2 events (2–7 ppm), where the instrument performance is the limiting factor and may only allow for the distinction between very different endmembers, such as the role of terrestrial versus oceanic carbon cycle processes.
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Madhavan, Bomidi Lakshmi, John Kalisch, and Andreas Macke. "Shortwave surface radiation network for observing small-scale cloud inhomogeneity fields." Atmospheric Measurement Techniques 9, no. 3 (March 18, 2016): 1153–66. http://dx.doi.org/10.5194/amt-9-1153-2016.
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Abstract. As part of the High Definition Clouds and Precipitation for advancing Climate Prediction Observational Prototype Experiment (HOPE), a high-density network of 99 silicon photodiode pyranometers was set up around Jülich (10 km × 12 km area) from April to July 2013 to capture the small-scale variability of cloud-induced radiation fields at the surface. In this paper, we provide the details of this unique setup of the pyranometer network, data processing, quality control, and uncertainty assessment under variable conditions. Some exemplary days with clear, broken cloudy, and overcast skies were explored to assess the spatiotemporal observations from the network along with other collocated radiation and sky imager measurements available during the HOPE period.
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Hubert, Daan, Klaus-Peter Heue, Jean-Christopher Lambert, Tijl Verhoelst, Marc Allaart, Steven Compernolle, Patrick D. Cullis, et al. "TROPOMI tropospheric ozone column data: geophysical assessment and comparison to ozonesondes, GOME-2B and OMI." Atmospheric Measurement Techniques 14, no. 12 (November 30, 2021): 7405–33. http://dx.doi.org/10.5194/amt-14-7405-2021.
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Abstract. Ozone in the troposphere affects humans and ecosystems as a pollutant and as a greenhouse gas. Observing, understanding and modelling this dual role, as well as monitoring effects of international regulations on air quality and climate change, however, challenge measurement systems to operate at opposite ends of the spatio-temporal scale ladder. Aboard the ESA/EU Copernicus Sentinel-5 Precursor (S5P) satellite launched in October 2017, the TROPOspheric Monitoring Instrument (TROPOMI) aspires to take the next leap forward by measuring ozone and its precursors at unprecedented horizontal resolution until at least the mid-2020s. In this work, we assess the quality of TROPOMI's first release (V01.01.05–08) of tropical tropospheric ozone column (TrOC) data. Derived with the convective cloud differential (CCD) method, TROPOMI daily TrOC data represent the 3 d moving mean ozone column between the surface and 270 hPa under clear-sky conditions gridded at 0.5∘ latitude by 1∘ longitude resolution. Comparisons to almost 2 years of co-located SHADOZ ozonesonde and satellite data (Aura OMI and MetOp-B GOME-2) conclude to TROPOMI biases between −0.1 and +2.3 DU (<+13 %) when averaged over the tropical belt. The field of the bias is essentially uniform in space (deviations <1 DU) and stable in time at the 1.5–2.5 DU level. However, the record is still fairly short, and continued monitoring will be key to clarify whether observed patterns and stability persist, alter behaviour or disappear. Biases are partially due to TROPOMI and the reference data records themselves, but they can also be linked to systematic effects of the non-perfect co-locations. Random uncertainty due to co-location mismatch contributes considerably to the 2.6–4.6 DU (∼14 %–23 %) statistical dispersion observed in the difference time series. We circumvent part of this problem by employing the triple co-location analysis technique and infer that TROPOMI single-measurement precision is better than 1.5–2.5 DU (∼8 %–13 %), in line with uncertainty estimates reported in the data files. Hence, the TROPOMI precision is judged to be 20 %–25 % better than for its predecessors OMI and GOME-2B, while sampling at 4 times better spatial resolution and almost 2 times better temporal resolution. Using TROPOMI tropospheric ozone columns at maximal resolution nevertheless requires consideration of correlated errors at small scales of up to 5 DU due to the inevitable interplay of satellite orbit and cloud coverage. Two particular types of sampling error are investigated, and we suggest how these can be identified or remedied. Our study confirms that major known geophysical patterns and signals of the tropical tropospheric ozone field are imprinted in TROPOMI's 2-year data record. These include the permanent zonal wave-one pattern, the pervasive annual and semiannual cycles, the high levels of ozone due to biomass burning around the Atlantic basin, and enhanced convective activity cycles associated with the Madden–Julian Oscillation over the Indo-Pacific warm pool. TROPOMI's combination of higher precision and higher resolution reveals details of these patterns and the processes involved, at considerably smaller spatial and temporal scales and with more complete coverage than contemporary satellite sounders. If the accuracy of future TROPOMI data proves to remain stable with time, these hold great potential to be included in Climate Data Records, as well as serve as a travelling standard to interconnect the upcoming constellation of air quality satellites in geostationary and low Earth orbits.
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Giles, David M., Alexander Sinyuk, Mikhail G. Sorokin, Joel S. Schafer, Alexander Smirnov, Ilya Slutsker, Thomas F. Eck, et al. "Advancements in the Aerosol Robotic Network (AERONET) Version 3 database – automated near-real-time quality control algorithm with improved cloud screening for Sun photometer aerosol optical depth (AOD) measurements." Atmospheric Measurement Techniques 12, no. 1 (January 11, 2019): 169–209. http://dx.doi.org/10.5194/amt-12-169-2019.
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Abstract. The Aerosol Robotic Network (AERONET) has provided highly accurate, ground-truth measurements of the aerosol optical depth (AOD) using Cimel Electronique Sun–sky radiometers for more than 25 years. In Version 2 (V2) of the AERONET database, the near-real-time AOD was semiautomatically quality controlled utilizing mainly cloud-screening methodology, while additional AOD data contaminated by clouds or affected by instrument anomalies were removed manually before attaining quality-assured status (Level 2.0). The large growth in the number of AERONET sites over the past 25 years resulted in significant burden to the manual quality control of millions of measurements in a consistent manner. The AERONET Version 3 (V3) algorithm provides fully automatic cloud screening and instrument anomaly quality controls. All of these new algorithm updates apply to near-real-time data as well as post-field-deployment processed data, and AERONET reprocessed the database in 2018. A full algorithm redevelopment provided the opportunity to improve data inputs and corrections such as unique filter-specific temperature characterizations for all visible and near-infrared wavelengths, updated gaseous and water vapor absorption coefficients, and ancillary data sets. The Level 2.0 AOD quality-assured data set is now available within a month after post-field calibration, reducing the lag time from up to several months. Near-real-time estimated uncertainty is determined using data qualified as V3 Level 2.0 AOD and considering the difference between the AOD computed with the pre-field calibration and AOD computed with pre-field and post-field calibration. This assessment provides a near-real-time uncertainty estimate for which average differences of AOD suggest a +0.02 bias and one sigma uncertainty of 0.02, spectrally, but the bias and uncertainty can be significantly larger for specific instrument deployments. Long-term monthly averages analyzed for the entire V3 and V2 databases produced average differences (V3–V2) of +0.002 with a ±0.02 SD (standard deviation), yet monthly averages calculated using time-matched observations in both databases were analyzed to compute an average difference of −0.002 with a ±0.004 SD. The high statistical agreement in multiyear monthly averaged AOD validates the advanced automatic data quality control algorithms and suggests that migrating research to the V3 database will corroborate most V2 research conclusions and likely lead to more accurate results in some cases.
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Wang, Ning. "Intelligent Quaternion Ship Domains for Spatial Collision Risk Assessment." Journal of Ship Research 56, no. 03 (September 1, 2012): 170–82. http://dx.doi.org/10.5957/jsr.2012.56.3.170.
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In this article, a novel ship domain model termed intelligent quaternion ship domain (IQSD) has been proposed by effectively considering ship maneuverability and human factors. Unlike previous ship domains, the proposed IQSD is much more dependable and flexible for navigators to make decisions. The key characteristics are as followsthe domain size is determined by the quaternion including 4 radii, i.e., fore, aft, starboard, and port, which sufficiently take factors affecting the domain (i.e., ship maneuverability, speeds and courses, etc.) into account;the domain shape is modeled by another parameter k, which makes the IQSD more flexible because the ship boundary could be not only linear or nonlinear, but also thin or fat; 3) furthermore, the navigator states including skill ability and physical and mental states have been effectively modeled by a fuzzy system, which determines the shape parameter, k. To reasonably relate the IQSD to potential applications, i.e., collision risk assessment, collision avoidance and trajectory planning, etc., a generalized IQSD (GIQSD) with fuzzy boundaries has been developed by using fuzzy sets. As a consequence, the GIQSD would become more practical and convenient for applications because uncertainty and fuzzy information has been merged into the GIQSD. Furthermore, concepts of longitudinal and lateral risk based on the GIQSD have been defined to estimate the spatial collision risk (SCR) for ships encountered. Finally, comprehensive simulations have been conducted on various encounter situations and comparative studies with typical ship domains have been intensively analyzed. Simulation results demonstrate that the IQSD is more effective and flexible than previous ship domains, and the intelligent SCR based on the GIQSD is reasonable and dependable.