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The article presents a study which proposes a calibration technique for deriving three-wavelength spectral sky radiances in Granada, Spain. The study applies calibration matrices in the study of multiple sky conditions including cloudless, overcast and partially cloudy. It also uses radiative transfer model in performing the quantitative and qualitative analysis of the aforementioned sky images.

The article discusses the influence of the calibration on experimental ultraviolet (UV) Index at a midlatitude site in Granada, Spain. It provides an overview of the instrumentation and data used in the study. It talks about the calibration methods used in this work to obtain experimental UV Index values. It also presents and discusses the application of the different methods for obtaining UV Index.

Background and aims: The focus of this paper is on the improvement of substance use disorder (SUD) screening and measurement. Using a multi‐dimensional item response theory model, the bifactor model, we provide a psychometric harmonization between SUD, depression, anxiety, trauma, social isolation, functional impairment and risk‐taking behavior symptom domains, providing a more balanced view of SUD. The aims are to (1) develop the item‐bank, (2) calibrate the item‐bank using a bifactor model that includes a primary dimension and symptom‐specific subdomains, (3) administer using computerized adaptive testing (CAT) and (4) validate the CAT‐SUD in Spanish and English in the United States and Spain. Design Item bank construction, item calibration phase, CAT‐SUD validation phase. Setting: Primary care, community clinics, emergency departments and patient‐to‐patient referrals in Spain (Barcelona and Madrid) and the United States (Boston and Los Angeles). Participants/cases: Calibration phase: the CAT‐SUD was developed via simulation from complete item responses in 513 participants. Validation phase: 297 participants received the Composite International Diagnostic Interview (CIDI) and the CAT‐SUD. Measurements A total of 252 items from five subdomains: (1) SUD, (2) psychological disorders, (3) risky behavior, (4) functional impairment and (5) social support. CAT‐SUD scale scores and CIDI SUD diagnosis. Findings Calibration: the bifactor model provided excellent fit to the multi‐dimensional item bank; 168 items had high loadings (> 0.4 with the majority > 0.6) on the primary SUD dimension. Using an average of 11 items (four to 26), which represents a 94% reduction in respondent burden (average administration time of approximately 2 minutes), we found a correlation of 0.91 with the 168‐item scale (precision of 5 points on a 100‐point scale). Validation: strong agreement was found between the primary CAT‐SUD dimension estimate and the results of a structured clinical interview. There was a 20‐fold increase in the likelihood of a CIDI SUD diagnosis across the range of the CAT‐SUD (AUC = 0.85). Conclusions: We have developed a new approach for the screening and measurement of SUD and related severity based on multi‐dimensional item response theory. The bifactor model harmonized information from mental health, trauma, social support and traditional SUD items to provide a more complete characterization of SUD. The CAT‐SUD is highly predictive of a current SUD diagnosis based on a structured clinical interview, and may be predictive of the development of SUD in the future. [ABSTRACT FROM AUTHOR]

Hospitals present a widely recognized margin for energy conservation due to their elevated final energy use intensity. Specifically, operating rooms are among the functional areas with greatest energy demand in hospitals, given the stringent indoor conditions for patients and surgical staff. However, energy efficiency in surgical facilities has traditionally been overlooked by the scientific literature in favor of guaranteeing adequate air quality conditions. This paper assesses the potential energy savings that could be achieved in a surgical suite in a Spanish hospital by lowering the current ventilation rates to the lowest energy-demanding values recommended by the proper Spanish standard and other international codes. Likewise, the paper assesses the actual hygrothermal and ventilation conditions in the suite based on the results of a continuous monitoring campaign performed for a period of 12 days. Simulations undertaken with a dynamic energy model specifically developed and calibrated for this work revealed that the average energy intensity of the suite is 1021 kWh/m 2 /year (1685 kWh/m 2 /year for operating rooms), with 80% of the total annual thermal demand corresponding to periods of inactivity. In addition, energy savings between 40% and 80% are possible while complying with both national and international standards. [ABSTRACT FROM AUTHOR]

Mathematical models are a fundamental tool in the learning process of environmental engineering. These models need to be calibrated in order to be used by future engineers as a simulation tool for the represented problems. This paper deals with the concept of computational models calibration applied to higher environmental engineering studies. In this paper, we depict a methodology to calibrate water quality models, as an educational example that represents the environmental problem of dissolved oxygen in a stream. This methodology is based on defining two types of parameters involved in calibration. First, internal parameters appear in the equations from semi-empirical estimations and can be found within some intervals. Genetic algorithms are proposed to estimate them. Second, experimental measurements enter into equations as external parameters. They affect the accuracy of the final solutions. Therefore, an uncertainty analysis has to be performed. Finally, a termination criterion for calibration has been proposed, based on the overlap between the confidence intervals of predicted and measured values. By developing this methodology, we provide awareness to our students of the importance of calibration of mathematical models so that they can apply them in their future simulation of environmental problems. Students identify the possible sources of uncertainty at each stage of the environmental model performance and apply them in this particular problem, Genetic Algorithm Techniques, as a computational tool to improve the accuracy of their model predictions. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 795-805, 2011 [ABSTRACT FROM AUTHOR]

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Wave reanalysis databases (WRDBs) offer important advantages for the statistical characterization of wave climate (continuous time series, good spatial coverage, constant time span, homogeneous forcing, and more than a 40-yr-long time series) and for this reason, they have become a powerful tool for the design of offshore and coastal structures. However, WRDBs are not quantitatively perfect and corrections using instrumental observations must be addressed before they are used; this process is called calibration. The calibration is especially relevant near the coast and in areas where the orography is complex, since in these places the inaccuracy of WRDB is evident because of the bad description of the wind fields (i.e., insufficient forcing resolution). The quantitative differences between numerical and instrumental data suggest that different corrections should be applied depending on the mean direction of the sea state. This paper proposes a calibration method based on a nonlinear regression problem, where the corresponding correction parameters vary smoothly along the possible wave directions by means of cubic splines. The correction of significant wave height is performed using instrumental data: (i) buoy records and/or (ii) satellite data. The performance of the method is illustrated considering data from different locations around Spain. [ABSTRACT FROM AUTHOR]

Abstract: Rodríguez-Ramírez and Yáñez-Camacho (2008), Rodríguez-Vidal et al. (2009) and Rodríguez-Ramírez et al. (2009) have kept an ongoing discussion about the validity of radiocarbon ages in reconstructing Holocene palaeogeographical models in the Gulf of Cadiz. The discussion considered the validity and correctness of the ΔR value to be used in the area to calibrate radiocarbon ages of marine samples. These papers suggest that the ΔR value proposed by Lario (1996) and Dabrio et al. (1999, 2000) is erroneous, and consequently, that all the evolutionary models based on radiocarbon ages from marine samples that have been proposed in this area since 1996 must be revised. However, the papers commented here use erroneously the R, regional R and ΔR values. After reviewing the published data, it is apparent that the most reliable values of ΔR in the Gulf of Cadiz for middle-late Holocene samples range between ΔR =35±85yr and ΔR =95±15yr. This means that the values used in Lario (1996) and Dabrio et al. (1999, 2000) fall in this range, and also that the calibrated ages used by several authors adopting these values are fully reliable. Calibrations using ΔR values inside this range do not yield significant differences in terms of geological age owing to the magnitude of errors resulting from the methods employed. [ABSTRACT FROM AUTHOR]

This paper presents the design, construction and testing of a new photodiode-based pyranometer for the visible spectral range (approx. 400 to 750 nm), whose principal characteristics are: accuracy, ease of connection, immunity to noise, remote programming and operation, interior temperature regulation, cosine error minimisation and all this at a very low cost, tens of times lower than that of commercial thermopile-based devices. This new photodiode-based pyranometer overcomes traditional problems in this type of device and offers similar characteristics to those of thermopile-based pyranometers and, therefore, can be used in any installation where reliable measurement of solar irradiance is necessary, especially in those where cost is a deciding factor in the choice of a meter. This new pyranometer has been registered in the Spanish Patent and Trademark Office under the number P200703162. [ABSTRACT FROM AUTHOR]

The joint use of multiresolution sensors from different satellites offers many opportunities to describe vegetation and its dynamics. This paper introduces the concept of a virtual constellation (defined as an ensemble of all Earth Observation satellites in orbit that satisfy common requirements) for agricultural applications and contributes to providing the necessary inter-sensor calibration methodology for spectral reflectances and NDVI. For this purpose, we performed an observational study, comparing reflectances and the Normalized Difference Vegetation Index (NDVI), from near-synchronous image pairs of Landsat 7 Enhanced Thematic Mapper Plus (ETM+), as the reference sensor and Landsat 5 Thematic Mapper (TM), IRS 1C/D LISS-III (LISS), Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), QuickBird, and NOAA Advanced Very High-resolution Radiometer (AVHRR). Linear relationships were found for the intercalibration of reflectances and NDVI from one sensor to another, for all sensors, provided that some spatial aggregation was performed. The main source of data dispersion in our linear cross-sensor translation equations is the geolocation uncertainty inherent in the process of geometric correction. Consequently, spatial aggregation always needs to be performed if (different or the same) sensors are to be used to derive time-series of biogeophysical parameters over heterogeneous areas. The homogenous zone approach developed here is recommended as an excellent tool for deriving robust new cross-sensor relationships, provided that the selected homogeneous crops cover the full NDVI range. The linear cross-sensor relationships derived from one image pair were shown to be valid for the whole season and for all areas with similar vegetation and climate. [ABSTRACT FROM AUTHOR]

Evaporation is gaining increasing attention as a calibration and evaluation variable in hydrologic studies that seek to improve the physical realism of hydrologic models and go beyond the long‐established streamflow‐only calibration. However, this trend is not yet reflected in sensitivity analyses aimed at determining the relevant parameters to calibrate, where streamflow has traditionally played a leading role. On the basis of a Pareto optimization approach, we propose a framework to integrate the temporal dynamics of streamflow and evaporation into the sensitivity analysis and calibration stages of the hydrologic modeling exercise, here referred to as "Pareto‐based sensitivity analysis" and "multiobjective calibration." The framework is successfully applied to a case study using the Variable Infiltration Capacity (VIC) model in three catchments located in Spain as representative of the different hydroclimatic conditions within the Iberian Peninsula. Several VIC vegetation parameters were identified as important to the performance estimates for evaporation during sensitivity analysis, and therefore were suitable candidates to improve the model representation of evaporative fluxes. Sensitivities for the streamflow performance, in turn, were mostly driven by the soil and routing parameters, with little contribution from the vegetation parameters. The multiobjective calibration experiments were carried out for the most parsimonious parameterization after a comparative analysis of the performance gains and losses for streamflow and evaporation, and yielded optimal adjustments for both hydrologic variables simultaneously. Results from this study will help to develop a better understanding of the trade‐offs resulting from the joint integration of streamflow and evaporation data into modeling frameworks. Key Points: Vegetation parameters are rarely considered in sensitivity analysis and their potential as calibration targets remains unexploredVIC vegetation parameters reflect high sensitivities toward evaporation and lead to an improvement in model performance during calibrationCombining Pareto‐based sensitivity analysis and multiobjective calibration improves the representation of both streamflow and evaporation [ABSTRACT FROM AUTHOR]

In this paper, the HBV-TEC hydrological model is presented. The development of this model version, aims to provide researchers and scholars with a stable and robust implementation of the HBV hydrological model based on the R programming language. To evaluate its performance, the HBV-TEC model was applied to three subcatchments of the Aguacaliente river catchment, an experimental catchment located in the province of Cartago, Costa Rica. Results suggest a satisfactory performance of the model for two subcatchments and an unsatisfactory performance of the remaining subcatchment; most of which could be attributed to unsufficient meteorological data along with a highly heterogeneous spatial rainfall-distribution. [ABSTRACT FROM AUTHOR]

Cellular automata models are popular tools for exploring future land change pathways. But simulation modelling approaches often focus too narrowly on calibration against historic reference maps, limiting the diversity of possible outcomes. We argue that, contrary to what is commonly believed, there is no 'best model', and that model specification and calibration accuracy depend on the objective of the research. We propose a multi-model ensemble approach, in which a wide range of models and calibration rules sets are systematically tested against multiple metrics. We apply our approach to a case study in Spain. No single model performed well for all statistics, illustrating the danger of cherry-picking statistics for best performance. In our case study, accounting for historic land changes in model design was useful for simulating compact urban development, but limited the variability of simulation outcomes. The accessibility model driver improved urban pattern replication, while suitability without accessibility was useful for simulating low-density development encroaching on natural areas. Rather than abandoning calibrations that show low agreement with reference maps based on a small number of metrics we should seek to understand what each metric is telling us and use this information to enrich the diversity of simulated outcomes. [ABSTRACT FROM AUTHOR]

Abstract: The application of the regional marine 14C reservoir effect (ΔR) to obtain an accurate calibration of conventional marine shell 14C dates requires prior research concerning the oceanographic conditions and the ΔR of that region. Rodríguez-Ramírez and Yánez-Camacho [A. Rodríguez-Ramírez, C.M. Yánez-Camacho, Formation of chenier plain of the Doñana marshland (SW Spain): Observations and geomorphic model, Marine Geology 254 (2008) 187–196] and afterwards A. Rodríguez-Ramírez, J.A. Morales, J. Borrego and E.G. San Miguel in a reply [A. Rodríguez-Ramírez, J.A. Morales, J. Borrego, E.G. San Miguel, Reply to the comment on “Formation of chenier plain of the Doñana marshland (SW Spain): Observations and geomorphic model” by A. Rodríguez-Ramírez and C.M. Yáñez-Camacho [Marine Geology 254 (2008) 187–196], Marine Geology 263 (2009) 123–125] to the comment by J. Rodríguez-Vidal, F. Ruiz and L.M. Cáceres on the paper mentioned above [J. Rodríguez-Vidal, F. Ruiz, L. M. Cáceres, Comment on “Formation of chenier plain of the Doñana marshland (SW Spain): Observations and geomorphic model” by A. Rodríguez-Ramírez, C.M. Yáñez-Camacho [Marine Geology 254 (2008) 187–196], Marine Geology 263 (2009) 120–122] use, in both cases, not only incorrect ΔR values for the calibration of 14C dates obtained from shell samples collected from the east coast of the Gulf of Cádiz, but they also confuse the ΔR concept with that of R(t), the 14C reservoir age. Because the misunderstanding of these concepts by these authors and, in the first case, also their failure to take into account the ΔR values obtained by us (and already published) from the east coast of Gulf of Cádiz, all the calibrated dates presented either in the first paper or in the reply cannot be accepted. Here I present a new calibrated dataset using accurate ΔR values and I recommend that the conclusions obtained by Rodríguez-Ramírez and their collaborators be revised, as J. Rodríguez-Vidal, F. Ruiz and L.M. Cáceres proposed in their comment. [Copyright &y& Elsevier]

In this paper, an experimental and numerical approach to the characterization of thermal bridges is presented. The need for this characterization was found within an experimental study in a 2 floor high façade. This façade was constructed with 3 concrete elements which were placed in it to produce a similar thermal bridge effect to the one created by floor slabs traditional building construction in Spain. Commonly applied thermal assessments perform one-dimensional heat transfer analysis over planar elements such as the façades studied in this experiment. However, it is well known that thermal bridges are locations in buildings where one-dimensional heat transfer analysis cannot be applied. This problem was approached by creating a numerical 2D thermal model which was calibrated against experimental data from several temperature and heat flux sensors which were located at specific points in the thermal bridge elements. [ABSTRACT FROM AUTHOR]

The oscillation between the promise and the disappointment of biobanks as techno‐scientific infrastructures for contemporary biomedical research is frequent in the literature. In this article, we analysed how the precariousness of biobanks is leading to shifts in the focus of biobanking in Spain, where there are calls for some practices to be rearticulated. Drawing upon fieldwork and interviews with biobankers, we looked at which practices are highlighted for change to make biobanks worth maintaining and keep them afloat. We analysed these practices to unpack the values biobankers deploy to make sense of biobanking and turn it into two worthiness criteria: social return and dynamism. These criteria are intertwined and revolve around ethically calibrating the accumulation and sharing practices, 'sharing but not too much'. The porosity of biobanking practices and legislation, not to mention over a decade of austerity measures make biobanks fragile scientific infrastructures in Spain. We examine how biobanking practices are shifting in Spain to stay in the precarious techno‐scientific present while challenging assumptions on cryopreservation and preparedness. Our local account highlights the relevance of further inquiries on shifts in biobanking to attend to which kinds of biomedical research and knowledge might be coproduced by such infrastructural reconfigurations. [ABSTRACT FROM AUTHOR]

Abstract: Urban growth models developed in the second half of the 20th century have allowed for a better understanding of the dynamics of urban growth. Among these models, cellular automata (CA) have become particularly relevant because of their ability to reproduce complex spatial and temporal dynamics at a global scale using local and simple rules. In the last three decades, many urban CA models that proved useful in the simulation of urban growth in large cities have been implemented. This paper analyzes the ability of some of the main urban CA models to simulate growth in a study area with different characteristics from those in which these models have been commonly applied, such as slow and low urban growth. The comparison of simulation results has allowed us to analyze the strengths and weaknesses of each model and to identify the models that are best suited to the characteristics of the study area. Results suggest that models which simulate several land uses can capture better land use dynamics in the study area but need more objective and reliable calibration methods. [Copyright &y& Elsevier]

Abstract: This paper proposes an approach to calibrate incentives for continuity of supply in electricity distribution in Spain. This approach consists on the estimation of the impact of continuity of supply improvements on distribution network costs. For this purpose, distribution costs resulting from different continuity of supply requirements are computed by a reference network model (RNM). The results obtained from the RNM are used to estimate a cost-function that considers continuity of supply a cost driver for distribution costs. This methodology is applied to three Spanish areas of service (an urban one, a semi-urban one and a rural one) in such a way that differences in distribution costs caused by the characteristics of the area type can be taken into account. The analysis indicated that distribution costs are more sensitive to continuity of supply improvements in rural areas of service. It also demonstrated that the incentive for reducing number of service interruptions should be higher than the incentive for reducing duration of service interruptions. Finally, the current Spanish incentive scheme for continuity of supply was analyzed under the perspective of the proposed approach. [Copyright &y& Elsevier]

Summary: The roughness calibration of floodplain and channels represents an important issue for flood studies. This paper discusses the genesis of scars on trees and their use as benchmarks in roughness calibration. In addition, it presents a methodology to reconstruct unrecorded flood discharge in the Alberche basin of the Spanish Central System. The study is based on the combined use of dendrogeomorphic evidence (i.e. scars on trees), data from the Navaluenga flow gauge (Avila Province) as well as a 1D/2D coupled numerical hydraulic model. A total of 49 scars have been analyzed with dendrogeomorphic techniques. Scar dates are in concert with seven flood events documented in the systematic record (i.e. 1989, 1993, 1996, 2000, 2002, 2003, and 2005). We were also able to identify an additional event dated to 1970, which is before the flow gauge was installed at Navaluenga. Based on the rating curve obtained from the flow gauge, cross-sectional area and data from hydraulic modelling, we cannot find a statistically significant difference between water depths registered at the flow gauge and scar heights on trees (p-value>0.05), indicating that scars would have been generated through the impact of floating wood and that scars on trees would represent a valuable and accurate proxy for water depth reconstruction. Under this premise, we have estimated the peak discharge of the 1970 flood event to 1684.3±519.2m3 s−1; which renders this event the largest documented flood for the Alberche River at Navaluenga. In a last analytical step, we discuss the use of scars on trees as benchmark for roughness calibration in ungauged or shortly recorded basins and address the added value of dendrogeomorphic data in flood frequency analysis. [ABSTRACT FROM AUTHOR]

Abstract: Based on calcareous nannofossil assemblages identified in four expanded and well-dated sections from the Basque-Cantabrian Basin, the main objective of this paper is to improve the knowledge of the Pliensbachian calcareous nannofossil events, and to calibrate these events to the ammonite zones established for this area. The semiquantitative analysis of more than 140 smear slides from the Tudanca and Santotis sections, and the re-analysis of more than 200 smear slides from the Camino and San Andrés sections, have been carried out in order to describe the succession of calcareous nannofossil assemblages. Related to their composition changes, we have recognized and calibrated to the ammonite zones two main events: the first occurrences (FOs) of Similiscutum cruciulus and Lotharingius hauffii, and six secondary events: the FOs of Biscutum novum, Biscutum grande, Biscutum finchii, Lotharingius barozii and the FCOs (first common occurrences) of Calcivascularis jansae and L. hauffii. In the Camino and San Andrés sections, we also identify the FOs of Biscutum dubium, Bussonius prinsii and Lotharingius sigillatus. The obtained data allow us to assess the degree of reproducibility of the Pliensbachian calcareous nannofossil events in the studied area. The biohorizon succession recognized in the Basque-Cantabrian Basin are compared to those proposed for NW Europe, Lusitanian Basin, Italy and Southern France. [Copyright &y& Elsevier]

Abstract: The AHS (airborne hyperspectral scanner) instrument has 80 spectral bands covering the visible and near infrared (VNIR), short wave infrared (SWIR), mid-infrared (MIR), and thermal infrared (TIR) spectral range. The instrument is operated by Instituto Nacional de Técnica Aerospacial (INTA) and it has been involved in several field campaigns since 2004. The main goal of this paper is to analyze the feasibility of retrieving land surface temperature from the 10 AHS thermal infrared bands, from 71 to 80, located in the region between 8 and 13μm. For this purpose, three different methods have been considered: (i) the single-channel method, which uses only one thermal band; (ii) the split-window method, which uses a combination of two thermal bands; and (iii) the TES (temperature and emissivity separation) method, which needs at least four thermal bands. The calibration of the AHS thermal bands and the algorithms have been tested with in situ measurements collected in the framework of the SPARC (Spectra Barrax Campaign) and EAGLE (Exploitation of AnGular effects in Land surfacE observations from satellites) field campaigns, which took place simultaneously in the agricultural area of Barrax (Albacete, Spain), and also in the framework of the AGRISPECTRA field campaign, carried out over an olive orchard in Córdoba (Spain), in July 2004. AHS flights were conducted at two different altitudes, 975m and 2745m above ground level. The results show that AHS bands 71 (8.18μm), 72 (8.66μm), and 73 (9.15μm) were affected by a calibration problem. Taking into account that AHS bands 74 (9.60μm) and 80 (12.93μm) are located in an absorption region, bands from 75 to 79 have been finally selected for land surface temperature retrieval. The single-channel method has been applied to AHS band 75 (10.07μm), which shows the highest atmospheric transmissivity, whereas the split-window method has been applied to the combination between bands 75 and 79 (12.35μm), which provides the best results according to simulated data. All the AHS thermal bands ranging from 75 to 79 have been used in the TES method. The tests conducted on the different algorithms used in this study show that single-channel and split-window methods provided similar results, with root mean square errors (RMSE) between 1.6 and 1.9K. The TES method slightly improved the results, with a RMSE of 1.4K. [Copyright &y& Elsevier]

Featured Application: The methodology proposed in this manuscript makes it possible to improve the estimation of flood zones and their flow depth values in situations where there are no available bathymetric data of the channel (or they are scarce and do not allow for its shape reconstruction). It could improve flood risk assessment too. The accurate estimation of flood risk depends on, among other factors, a correct delineation of the floodable area and its associated hydrodynamic parameters. This characterization becomes fundamental in the flood hazard analyses that are carried out in urban areas. To achieve this objective, it is necessary to have a correct characterization of the topography, both inside the riverbed (bathymetry) and outside it. Outside the riverbed, the LiDAR data led to an important improvement, but not so inside the riverbed. To overcome these deficiencies, different models with simplified bathymetry or modified inflow hydrographs were used. Here, we present a model that is based upon the calibration of the Manning's n value inside the riverbed. The use of abnormally low Manning's n values made it possible to reproduce both the extent of the flooded area and the flow depth value within it (outside the riverbed) in an acceptable manner. The reduction in the average error in the flow depth value from 50–75 cm (models without bathymetry and "natural" Manning's n values) to only about 10 cm (models without bathymetry and "calibrated" Manning's n values), was propagated towards a reduction in the estimation of direct flood damage, which fell from 25–30% to about 5%. [ABSTRACT FROM AUTHOR]

On-Line monitoring evaluates instrument channel performance by assessing its consistency with other plant indications. Industry and EPRI experience at several plants has shown this overall approach to be very effective in identifying instrument channels that are exhibiting degrading or inconsistent performance characteristics “On-Line Monitoring of Instrument Channel Performance by EPRI (2000)”.On-Line monitoring of instrument channels provides information about the condition of the monitored channels through accurate, more frequent monitoring of each channel''s performance over time. This type of performance monitoring is a methodology that offers an alternate approach to traditional time-directed calibration. On-line monitoring of these channels can provide an assessment of instrument performance and provide a basis for determining when adjustments are necessary. Elimination or reduction of unnecessary field calibrations can reduce associated labor costs, reduce personnel radiation exposure and reduce the potential for miss-calibration.PEANO “A Neuro-Fuzzy Model Applied to Full Range Signal Validation of PWR Nuclear Power Plant Data by Fantoni (2000)” is a system for on-line calibration monitoring developed in the years 1995–2000 at the Institutt for energiteknikk (IFE), Norway, which makes use of Artificial Intelligence techniques for its purpose. The system has been tested successfully in Europe in off-line tests with EDF (France), Tecnatom (Spain) and ENEA (Italy). PEANO is currently installed and used for on-line monitoring at the HBWR reactor in Halden. This paper describes the results of performance tests on PEANO with real data from a US PWR plant, in the framework of a co-operation among IFE, EPRI and Edan Engineering, to evaluate the potentials of PEANO for future installations in US nuclear plants. [Copyright &y& Elsevier]

Hydrological models are widely used tools in water resources management. Their successful application requires an efficient calibration of the model parameters. Nowadays, there are very powerful global search methods applied to this end, but they have the disadvantage of presenting a high computational cost, because the numerical model to be calibrated needs to be evaluated a large number of times with different parameter sets. In this context, surrogate models can reduce significantly the run time of hydrological models, easing the total computational burden of global search methods. In the present work, we propose and explore the combination of a swarm intelligence-based optimization method, the artificial bee colony algorithm, with a surrogate model based on artificial neural networks in order to calibrate hydrological models. The proposed approach (ABC-ANN) is applied to the calibration and validation of a nine-parameter continuous hydrological model in two basins located in the northwest of Spain. Several aspects of the algorithm are evaluated, including its capability to calibrate the model parameters and its efficiency in terms of CPU time compared to a standard implementation of the ABC algorithm. Results show that the ABC-ANN algorithm is able to identify the location of suitable parameter sets with an accuracy rate within 89 and 99 %, and a reduction in CPU time of more than three orders of magnitude when compared to a sequential implementation. In addition, the frequency distribution of the parameter sets identified gives valuable information about the sensitivity of model output to the input parameters. [ABSTRACT FROM AUTHOR]

Abstract: It is paradoxical that work in question (Rodríguez-Ramírez and Yánez-Camacho, 2008) has started a debate in the scientific community about the values of the reservoir effect used in the 14C dates in the Gulf of Cádiz, since in their Comments Rodríguez-Vidal et al. (2009), Monges Soares (2010-this issue) and Lario et al. (2010-this issue), have not taken into account that these values are in reference to earlier studies (Morales et al., 2008). The new figures suggested by Rodríguez-Vidal et al. (2009) and Monges Soares (2010-this issue) for this part of the Gulf of Cadiz (Soares, 2008) had not been reported when the earlier papers were accepted and published. The values for the reservoir effect applied on the South Atlantic coast of the Iberian Peninsula need to be continually adjusted, due to the new contributions that have been made in recent years as a result of developments of the research being undertaken in this field. Without doubt, in the future, as further progress is made, the values will be even more finely tuned and the present ones will become obsolete, as our understanding of marine and estuarine dynamics in this sector over the last few thousand years is a topic which remains open to new interpretations. The new figures for the reservoir effect are an important contribution in determining more accurately the chronology of events in the Holocene, and they make it necessary to revise the previous studies on marine Holocene formations in the Gulf of Cadiz with 14C dates, owing to the errors that have occurred in this respect. For this reason the Comment should not be aimed at one paper alone, and instead this matter should be reviewed at a regional level. Those of us who are not specialists in the topic welcome these clarifications, which can help shed additional light on the chronological problems. [ABSTRACT FROM AUTHOR]

After 5 years in orbit, the Global Precipitation Measurement (GPM) mission has produced enough quality-controlled data to allow the first validation of their precipitation estimates over Spain. High-quality gauge data from the meteorological network of the Spanish Meteorological Agency (AEMET) are used here to validate Integrated Multisatellite Retrievals for GPM (IMERG) level 3 estimates of surface precipitation. While aggregated values compare notably well, some differences are found in specific locations. The research investigates the sources of these discrepancies, which are found to be primarily related to the underestimation of orographic precipitation in the IMERG satellite products, as well as to the number of available gauges in the GPCC gauges used for calibrating IMERG. It is shown that IMERG provides suboptimal performance in poorly instrumented areas but that the estimate improves greatly when at least one rain gauge is available for the calibration process. A main, generally applicable conclusion from this research is that the IMERG satellite-derived estimates of precipitation are more useful (r2 > 0.80) for hydrology than interpolated fields of rain gauge measurements when at least one gauge is available for calibrating the satellite product. If no rain gauges were used, the results are still useful but with decreased mean performance (r2 ≈ 0.65). Such figures, however, are greatly improved if no coastal areas are included in the comparison. Removing them is a minor issue in terms of hydrologic impacts, as most rivers in Spain have their sources far from the coast. [ABSTRACT FROM AUTHOR]

Aims: To analyze and quantify the sociodemographic, behavioral, and clinical factors influencing the oral pain and eating difficulties reported by Spanish 35- to 44-year-old adults and more elderly people in the most recent Spanish National Oral Health Survey. Methods: Pain and chewing difficulties were gathered in a Likert-scale format from a representative sample of the Spanish general population between the ages of 35 and 44 years (n = 540) and 65 to 74 years (n = 540). Risk factors were identified using bivariate analysis, after which the crude association between risk factors (sociodemographic, behavioral, and clinical) and outcome variables (pain and eating problems) was assessed by adjusted odds ratios, calculated by means of multivariate logistic regression. Results: In the 35- to 44-year-old adults, eating problems were mainly associated with caries and prosthetic treatment needs and oral pain by the number of decayed teeth. In the more elderly individuals, eating problems and oral pain were influenced by prosthetic needs and the number of missing teeth. Female sex was seen to be a risk factor for suffering pain and eating restrictions. Additionally, several independent variables such as social class, place of residence, brushing habits, or periodontal needs became nonsignificant after logistic regression modelling. Conclusion: According to this high-specificity regression model, caries and prosthetic treatment needs should be considered key factors in determining the oral well-being of the Spanish population. Missing teeth represent the most relevant influencing factor for the elderly and decayed teeth for younger adults. [ABSTRACT FROM AUTHOR]

The aim of this work was to apply a one-dimensional hydrodynamic and water quality DYRESM--CAEDYM model to the Boadella reservoir, Catalonia, Spain. Thus, simulation length was two years (2000 and 2001) with the aim to predict temperature, dissolved inorganic phosphorus and chlorophyll. The DYRESM--CAEDYM input data were meteorological data, river inflow and outflow data, morphometry parameters, an initial profile and file configuration data. The CAEDYM model also requires a configuration file and initial profiles for all the water quality data, but these data are not complete. Therefore, simulation may not be reliable or well analysed because of a lack of field nutrient data; so we will focus on the simulation of temperature, dissolved oxygen and chlorophyll. After simulation and calibration, coupling of those models might be a good tool to have an idea about Boadella reservoir water quality behaviour. [ABSTRACT FROM AUTHOR]

Aims and objectives: To evaluate both concordance among those measurements obtained by three different pulse oximeters currently used by nursing professionals in hospital units and the factors which can influence this concordance. Background: Many models of wireless pulse oximeters in the present market do not offer possibility of calibration and, therefore, they do not ensure patients' safety in daily clinical practice. Design: This is a descriptive and cross-sectional study. The sample of patients (140) was selected from such hospital units, and all of them had to fulfil inclusion and exclusion criteria for participation. Methods: The instruments used to carry out this research were a monitor (calibrated), two models of portable wireless pulse oximeters (used for 3 years by the nursing staff, without being calibrated), a tympanic thermometer and a weather meter. The concordance correlation coefficient (CCC) was used to establish the concordance, whereas the Landis-Koch criteria were used to interpret the results. Results: The concordance among the three devices was considered as “good” (CCC: 0.925 and 0.974 (95%)). The CCC (0.925) for saturation measures was regarded as “very good”/”almost perfect,” and the pulse measure was considered as “very good” CCC 0.974, providing in both cases a high level of concordance (CCC > 0.91). Conclusions: The overall concordance as regards pulse and oxygen saturation among the three pulse oximeters analysed is considered as “very good” according to the Landis-Koch criteria. Relevance to clinical practice: There exists a “very good” concordance among two wireless oximeters which have been used by the health staff for 3 years and which did not offer any possibility of calibration and one monitor which belongs to the healthcare institution. This aspect is of crucial importance in daily clinical practice, and it is also relevant to ensure patient’s safety. [ABSTRACT FROM AUTHOR]

The Tramuntana range, in the northwestern sector of the island of Mallorca (Balearic Islands, Spain), is frequently affected by rockfalls which have caused significant damage, mainly along the road network. In this work, we present the procedure we have applied to calibrate and validate rockfall modelling in this region, using 103 cases of the available detailed rockfall inventory (630 rockfall events collected since the eighteenth century). We have exploited STONE (Guzzetti et al. 2002), a GIS-based rockfall simulation software which computes 2D and 3D rockfall trajectories starting from a DTM and maps of the dynamic rolling friction coefficient and of the normal and tangential energy restitution coefficients. The appropriate identification of these parameters determines the accuracy of the simulation. To calibrate them, we have selected 40 rockfalls along the range which include a wide variety of outcropping lithologies. Coefficients values have been changed in numerous attempts in order to select those where the extent and shape of the simulation matched the field mapping. Best results were summarized with the average statistical values for each parameter and for each geotechnical unit, determining that mode values represent more precisely the data. Initially, for the validation stage, 10 well-known rockfalls exploited in the calibration phase have been selected. Confidence tests have been applied to their modelling results taking into account not only the success but also the mistakes. The best accuracy is obtained when the rockfall has a preferential trajectory and worse results when the rockfall follows two or more trajectories. Additionally, the greater the rockfall runout length, the less precise the simulation is. We have further validated the calibrated parameters along the Ma-road (111 km), the main transportation corridor in the range, using 63 rockfall events that occurred during the past 18 years along the road. Of the rockfalls where source areas were properly identified, 81.5 % are well represented by STONE modelling, as the travel paths and the depositional areas are successfully ascertained. Results of the analysis have been used by the Road Maintenance Service of Mallorca to assess hazard and risk posed by rockfall at regional scale to design the road management plan. [ABSTRACT FROM AUTHOR]

Solar radiation () is a very important variable in agricultural meteorology, but it is measured at a very limited number of weather stations. In addition, data are usually low quality because of to sensor failure or lack of calibration. can be predicted from other meteorological measurements (e.g., air temperature), but the accuracy of these methods needs to be tested. In this work, the mechanistic model of Hargreaves-Samani, three modified versions of this model, a modified Bristow-Campbell equation, and the Mahmood-Hubbard model were evaluated at 56 sites in the Andalusian region in southern Spain. All of these methods use the daily temperature range of the air () to estimate . The estimated values of were compared with measurements of to check their suitability. The accuracy of the methods was primarily affected by the magnitude of , with larger resulting in a greater accuracy. Finally, the parameter of the Hargreaves-Samani equation () was adjusted to regional conditions using , improving the estimations of incoming solar radiation for a wide range. [ABSTRACT FROM AUTHOR]

A test bench has been developed for the magnetic measurements on the Phase Shifters for E-XFEL. It will be part of the Spanish in-kind contribution to this new research facility. [ABSTRACT FROM PUBLISHER]

This work summarizes the activities carried out by the SMOS (Soil Moisture and Ocean Salinity) Barcelona Expert Center (SMOS-BEC) team in conjunction with the CIALE/Universidad de Salamanca team, within the framework of the European Space Agency (ESA) CALIMAS project in preparation for the SMOS mission and during its first year of operation. Under these activities several studies were performed, ranging from Level 1 (calibration and image reconstruction) to Level 4 (land pixel disaggregation techniques, by means of data fusion with higher resolution data from optical/infrared sensors). Validation of SMOS salinity products by means of surface drifters developed ad-hoc, and soil moisture products over the REMEDHUS site (Zamora, Spain) are also presented. Results of other preparatory activities carried out to improve the performance of eventual SMOS follow-on missions are presented, including GNSS-R to infer the sea state correction needed for improved ocean salinity retrievals and land surface parameters. Results from CALIMAS show a satisfactory performance of the MIRAS instrument, the accuracy and efficiency of the algorithms implemented in the ground data processors, and explore the limits of spatial resolution of soil moisture products using data fusion, as well as the feasibility of GNSS-R techniques for sea state determination and soil moisture monitoring. [ABSTRACT FROM AUTHOR]

The article presents a study on the influence of using one-step and two-steps method on the experimental ultraviolet index (UVI) measured by a YES UVB-1 radiometer located in Granada, Spain for 2006-2009. Also, the study analyzes the deviation from the UVI values taken from the application of the calibration factors. Based on results, absolute mean differences between measured and modeled UVI data of the methods indicate an excellent performance for obtaining UVI data.

The article discusses a study on the ROFLEX system which was deployed in Spain for in situ detection of atmospheric iodine atoms and molecules based on resonance and off-resonance fluorescence caused by lamp emission. It mentions its combination of robustness, light weight and efficient excitation of radio-frequency discharge light sources with high sensitivity photon calculation. It also notes the achievement of an iodine fluorescence calibration through molecular quantitative detection.

Numerical modeling of dredged pits is conducted to investigate the hydrodynamic and morphodynamic interaction in offshore sand extractions. Based on an analytical formulation, a semianalytical numerical model (MEMPITS) has been developed to study the morphodynamic evolution of offshore (ho . 20 m) sand borrow areas. The numerical model has been applied to study the morphodynamic evolution of two offshore sand borrow areas in the Balearic Islands (Spain). Field data allowed a detailed characterization of the evolution of the sandpits. Time series of local hydrodynamics have been obtained using generation models (hindcast) combined with local wave and flow models. A verification of the simple model has been carried out using relatively slight adjustments to the calibration factors. The simple model provides good estimates of the infill rate and migration velocities of the offshore pits on the scale of years. This semianalytical tool allows a quick systematic investigation of the physical mechanisms as well as a etailed sensibility analysis regarding the pit design parameters. These parameters include location (water depth), pit length, width, depth, and orientation with respect to the mean flow. A nondimensional analysis based on the model is also carried out to explore the role of the different variables involved in the evolution of offshore sandpits. Based on the field data and the nondimensional analysis, some basic design recommendations for offshore sandpits are proposed. [ABSTRACT FROM AUTHOR]

Four rectangular sluice gates were calibrated for submerged-flow conditions using nearly 16,000 field-measured data points on Canal B of the B-XII irrigation scheme in Lebrija, Spain. Water depth and gate opening values were measured using acoustic sensors at each of the gate structures, and the data were recorded on electronic data loggers. Several gate calibration equations were tested and it was found that the rectangular sluice gates can be used for accurate flow measurement. The Energy-Momentum (E-M) equations proved to be sound. The calibration of the contraction coefficient, to be used in the energy equation, allowed good estimations of the discharge for three of the four gates studied. The gate for which the E-M method did not perform satisfactorily was located at the head of the canal with a unique nonsymmetric approach flow condition. Alternatively, we investigated the performance of the conventional discharge equation. The variation of the discharge coefficient, Cd, with the head differential, Δh, and the vertical gate opening, w, suggests that Cd be expressed as a function of these two variables. For the sluice gates considered in this study, the best empirical fit was obtained by expressing Cd as a parabolic function of w, although an exponential expression tested previously by other writers also produced satisfactory results. The greatest uncertainty in the variables considered in this study was in the calculated coefficient of discharge, and based on the uncertainty analysis, it is possible to quantify the uncertainty in the estimated discharge through a calibrated sluice gate. The discharge uncertainty in each of the four gates in this study decreases with increasing gate opening, and it decreases slightly with increasing head differentials. [ABSTRACT FROM AUTHOR]

Errors in the estimation of CO2 surface exchange by open-path eddy covariance, introduced during the removal of density terms [Webb et al. Quart J Roy Meteorol Soc 106:85–100, (1980) - WPL], can happen both because of errors in energy fluxes [Liu et al. Boundary-Layer Meteorol 120:65–85, (2006)] but also because of inaccuracies in other terms included in the density corrections, most notably due to measurements of absolute CO2 density (ρ c ). Equations are derived to examine the propagation of all errors through the WPL algorithm. For an open-path eddy covariance system operating in the Sierra de Gádor in south-east Spain, examples are presented of the inability of an unattended, open-path infrared gas analyzer (IRGA) to reliably report ρ c and the need for additional instrumentation to determine calibration corrections. A sensitivity analysis shows that relatively large and systematic errors in net ecosystem exchange (NEE) can result from uncertainties in ρ c in a semi-arid climate with large sensible heat fluxes ( H s ) and (wet) mineral deposition. When ρc is underestimated by 5% due to lens contamination, this implies a 13% overestimation of monthly CO2 uptake. [ABSTRACT FROM AUTHOR]

Good air quality is essential for both human beings and the environment in general. The three most harmful air pollutants are nitrogen dioxide (NO2), ozone (O3) and particulate matter. Due to the high cost of monitoring stations, few examples of this type of infrastructure exist, and the use of low-cost sensors could help in air quality monitoring. The cost of metal-oxide sensors (MOS) is usually below EUR 10 and they maintain small dimensions, but their use in air quality monitoring is only valid through an exhaustive calibration process and subsequent precision analysis. We present an on-field calibration technique, based on the least squares method, to fit regression models for low-cost MOS sensors, one that has two main advantages: it can be easily applied by non-expert operators, and it can be used even with only a small amount of calibration data. In addition, the proposed method is adaptive, and the calibration can be refined as more data becomes available. We apply and evaluate the technique with a real dataset from a particular area in the south of Spain (Granada city). The evaluation results show that, despite the simplicity of the technique and the low quantity of data, the accuracy obtained with the low-cost MOS sensors is high enough to be used for air quality monitoring. [ABSTRACT FROM AUTHOR]

Hydrological models are increasingly used for studying watershed behavior and its response to past and future events. The main objective of this study was to conduct a sensitivity analysis of the MOHID-Land model and identify the most relevant parameters/processes influencing river flow generation. MOHID-Land is a complex, physically based, three-dimensional model used for catchment-scale applications. A reference simulation was implemented in the Ulla River watershed, northwestern Spain. The sensitivity analysis focused on sixteen parameters/processes influencing water dynamics at that scale. River flow generation was influenced by the resolution of the simulation grid, soil water infiltration, and crop evapotranspiration. Baseflow was affected by soil hydraulic properties, the depth of the soil profile, and the dimensions of the river cross-sections. Peak flows were mostly constrained by Manning's coefficient in the river network, as well as the dimensions of the river cross-sections. The MOHID-Land model was then used to simulate daily streamflow during a 10-year period (2008−2017). Model simulations were compared against measured data at four hydrometric stations characterizing the natural flow regime of the Ulla River, resulting in coefficients of determination (R2) from 0.56 to 0.85; ratios of the standard deviation of the root mean square error to observation (RSR) between 0.4 and 0.67, and Nash and Sutcliffe model efficiency (NSE) values ranging from 0.55 to 0.84. The MOHID-Land model thus has the capacity to reproduce watershed behavior at a daily scale with reliable accuracy, constituting a powerful tool to improve water governance at the watershed scale. [ABSTRACT FROM AUTHOR]

Process-based crop models such as AquaCrop are useful for a variety of applications but must be accurately calibrated and validated. Sugar beet is an important crop that is grown in regions under water scarcity. The discrepancies and uncertainty in past published calibrations, together with important modifications in the program, deemed it necessary to conduct a study aimed at the calibration of AquaCrop (version 6.1) using the results of a single deficit irrigation experiment. The model was validated with additional data from eight farms differing in location, years, varieties, sowing dates, and irrigation. The overall performance of AquaCrop for simulating canopy cover, biomass, and final yield was accurate (RMSE = 11.39%, 2.10 t ha−1, and 0.85 t ha−1, respectively). Once the model was properly calibrated and validated, a scenario analysis was carried out to assess the crop response in terms of yield and water productivity to different irrigation water allocations in the two main production areas of sugar beet in Spain (spring and autumn sowing). The results highlighted the potential of the model by showing the important impact of irrigation water allocation and sowing time on sugar beet production and its irrigation water productivity. [ABSTRACT FROM AUTHOR]

Calibration of conceptual rainfall–runoff models (CRRM) for water-resource assessment (WRA) is a complicated task that contributes to the reliability of results obtained from catchments. In recent decades, the application of automatic calibration techniques has been frequently used because of the increasing complexity of models and the considerable time savings gained at this phase. In this work, the traditional Rosenbrock (RNB) algorithm is combined with a random sampling method and the Latin hypercube (LH) to optimize a multi-start strategy and test the efficiency in the calibration of CRRMs. Three models (the French rural-engineering-with-four-daily-parameters (GR4J) model, the Swedish Hydrological Office Water-balance Department (HBV) model and the Sacramento Soil Moisture Accounting (SAC-SMA) model) are selected for WRA at nine headwaters in Spain in zones prone to long and severe droughts. To assess the results, the University of Arizona's shuffled complex evolution (SCE-UA) algorithm was selected as a benchmark, because, until now, it has been one of the most robust techniques used to solve calibration problems with rainfall–runoff models. This comparison shows that the traditional algorithm can find optimal solutions at least as good as the SCE-UA algorithm. In fact, with the calibration of the SAC-SMA model, the results are significantly different: The RNB algorithm found better solutions than the SCE-UA for all basins. Finally, the combination created between the LH and RNB methods is detailed thoroughly, and a sensitivity analysis of its parameters is used to define the set of optimal values for its efficient performance. [ABSTRACT FROM AUTHOR]

Different types of measuring errors can increase the uncertainty of solar radiation measurements, but most common quality control (QC) methods do not detect frequent defects such as shading or calibration errors due to their low magnitude. We recently presented a new procedure, the Bias-based Quality Control (BQC), that detects low-magnitude defects by analyzing the stability of the deviations between several independent radiation databases and measurements. In this study, we extend the validation of the BQC by analyzing the quality of all publicly available Spanish radiometric networks measuring global horizontal irradiance (9 networks, 732 stations). Similarly to our previous validation, the BQC found many defects such as shading, soiling, or calibration issues not detected by classical QC methods. The results questioned the quality of SIAR, Euskalmet, MeteoGalica, and SOS Rioja, as all of them presented defects in more than 40% of their stations. Those studies based on these networks should be interpreted cautiously. In contrast, the number of defects was below a 5% in BSRN, AEMET, MeteoNavarra, Meteocat, and SIAR Rioja, though the presence of defects in networks such as AEMET highlights the importance of QC even when using a priori reliable stations. [ABSTRACT FROM AUTHOR]