scholarly journals Comparisons between ground-based FTIR and MIPAS N<sub>2</sub>O and HNO<sub>3</sub> profiles before and after assimilation in BASCOE

2007 ◽  
Vol 7 (2) ◽  
pp. 377-396 ◽  
Author(s):  
C. Vigouroux ◽  
M. De Mazière ◽  
Q. Errera ◽  
S. Chabrillat ◽  
E. Mahieu ◽  
...  
Keyword(s):  
Standard Deviation ◽  
High Latitude ◽  
Atmospheric Composition ◽  
Upper Troposphere ◽  
Before And After ◽  
Standard Deviations ◽  
Data Assimilation System ◽  
Good Agreement ◽  
Middle Stratosphere

Abstract. Within the framework of the Network for Detection of Atmospheric Composition Change (NDACC), regular ground-based Fourier transform infrared (FTIR) measurements of many species are performed at several locations. Inversion schemes provide vertical profile information and characterization of the retrieved products which are therefore relevant for contributing to the validation of MIPAS profiles in the stratosphere and upper troposphere. We have focused on the species HNO3 and N2O at 5 NDACC-sites distributed in both hemispheres, i.e., Jungfraujoch (46.5° N) and Kiruna (68° N) for the northern hemisphere, and Wollongong (34° S), Lauder (45° S) and Arrival Heights (78° S) for the southern hemisphere. These ground-based data have been compared with MIPAS offline profiles (v4.61) for the year 2003, collocated within 1000 km around the stations, in the lower to middle stratosphere. To get around the spatial collocation problem, comparisons have also been made between the same ground-based FTIR data and the corresponding profiles resulting from the stratospheric 4D-VAR data assimilation system BASCOE constrained by MIPAS data. This paper discusses the results of the comparisons and the usefullness of using BASCOE profiles as proxies for MIPAS data. It shows good agreement between MIPAS and FTIR N2O partial columns: the biases are below 5% for all the stations and the standard deviations are below 7% for the three mid-latitude stations, and below 10% for the high latitude ones. The comparisons with BASCOE partial columns give standard deviations below 4% for the mid-latitude stations to less than 8% for the high latitude ones. After making some corrections to take into account the known bias due to the use of different spectroscopic parameters, the comparisons of HNO3 partial columns show biases below 3% and standard deviations below 15% for all the stations except Arrival Heights (bias of 5%, standard deviation of 21%). The results for this species, which has a larger spatial variability, highlight the necessity of defining appropriate collocation criteria and of accounting for the spread of the observed airmasses. BASCOE appears to have more deficiencies in producing proxies of MIPAS HNO3 profiles compared to N2O, but the obtained standard deviation of less than 10% between BASCOE and FTIR is reasonable. Similar results on profiles comparisons are also shown in the paper, in addition to partial column ones.

scholarly journals Comparisons between ground-based FTIR and MIPAS N<sub>2</sub>O and HNO<sub>3</sub> profiles before and after assimilation in BASCOE

2006 ◽  
Vol 6 (5) ◽  
pp. 8335-8382
Author(s):  
C. Vigouroux ◽  
M. De Mazière ◽  
Q. Errera ◽  
E. Mahieu ◽  
P. Duchatelet ◽  
...  
Keyword(s):  
Standard Deviation ◽  
High Latitude ◽  
Atmospheric Composition ◽  
Upper Troposphere ◽  
Before And After ◽  
Standard Deviations ◽  
Data Assimilation System ◽  
Good Agreement ◽  
Middle Stratosphere

Abstract. Within the framework of the Network for Detection of Atmospheric Composition Change (NDACC), regular ground-based Fourier transform infrared (FTIR) measurements of many species are performed at several locations. Inversion schemes provide vertical profile information and characterization of the retrieved products which are therefore relevant for contributing to the validation of MIPAS profiles in the stratosphere and upper troposphere. We have focused on the species HNO3 and N2O at 5 NDACC-sites distributed in both hemispheres, i.e., Jungfraujoch (46.5° N) and Kiruna (68° N) for the northern hemisphere, and Wollongong (34° S), Lauder (45° S) and Arrival Heights (78° S) for the southern hemisphere. These ground-based data have been compared with MIPAS offline profiles (v4.61) for the year 2003, collocated within 1000 km around the stations, in the lower to middle stratosphere. To get around the spatial collocation problem, comparisons have also been made between the same ground-based FTIR data and the corresponding profiles resulting from the stratospheric 4D-VAR data assimilation system BASCOE. This paper discusses the results of the comparisons and the usefullness of using BASCOE profiles as proxies for MIPAS data. It shows good agreement between MIPAS and FTIR N2O partial columns: the biases are below 5% for all the stations and the standard deviations are below 7% for the three mid-latitude stations, and below 10% for the high latitude ones. The comparisons with BASCOE partial columns give standard deviations below 4% for the mid-latitude stations to less than 8% for the high-latitude ones. After making some corrections to take into account the known bias due to the use of different spectroscopic parameters, the comparisons of HNO3 partial columns show biases below 3% and standard deviations below 15% for all the stations except Arrival Heights (bias of 6%, standard deviation of 21%). The results for this species, which has a larger spatial variability, highlight the necessity of defining appropriate collocation criteria and of accounting for the spread of the observed airmasses. BASCOE appears to have more deficiencies in producing proxies of MIPAS HNO3 profiles compared to N2O, but the obtained standard deviation of less than 10% between BASCOE and FTIR is reasonable. Similar results on profiles comparisons are also shown in the paper, in addition to partial column ones.

scholarly journals Use of Mini-CT Specimens for Fracture Toughness Characterization of Low Upper-Shelf Linde 80 Weld Before and After Irradiation

2018 ◽  
Author(s):  
Mikhail A. Sokolov
Keyword(s):  
Fracture Toughness ◽  
Pressure Vessel ◽  
Master Curve ◽  
Collaborative Program ◽  
Before And After ◽  
Minimum Number ◽  
Real Practice ◽  
Reactor Pressure ◽  
Good Agreement

Mini-CT specimens are becoming a highly popular geometry for use in reactor pressure vessel (RPV) community for direct measurement of fracture toughness in the transition region using the Master Curve methodology. In the present study, Mini-CT specimens were machined from previously tested Charpy specimens of the Midland low upper-shelf Linde 80 weld in both, unirradiated and irradiated conditions. The irradiated specimens have been characterized as part of a joint ORNL-EPRI-CRIEPI collaborative program. The Linde 80 weld was selected because it has been extensively characterized in the irradiated condition by conventional specimens, and because of the need to validate application of Mini-CT specimens for low upper-shelf materials — a more likely case for some irradiated materials of older generation RPVs. It is shown that the fracture toughness reference temperatures, To, derived from these Mini-CT specimens are in good agreement with To values previously recorded for this material in the unirradiated and irradiated conditions. However, this study indicates that in real practice it is highly advisable to use a much larger number of specimens than the minimum number prescribed in ASTM E1921.

Assessment and documentation of incontinence-associated dermatitis after implementation of a standardised instrument: a comparative study

2019 ◽  
Vol 28 (Sup9) ◽  
pp. S4-S11 ◽  
Author(s):  
Mary Montague ◽  
Matthew Karafa ◽  
Nancy M. Albert
Keyword(s):  
Standard Deviation ◽  
Weighted Kappa ◽  
Severity Index ◽  
Skin Condition ◽  
Assessment Instrument ◽  
Clinical Nurses ◽  
Before And After ◽  
Implementation Period ◽  
Improved Accuracy ◽  
Good Agreement

Objective: In this study, clinical nurses' documentation of incontinence-associated dermatitis (IAD) were compared with wound expert documentation before and after implementing a valid, reliable severity index (SI) instrument. Methods: A prospective, non-equivalent, two group comparative design within three hospital medical units. Pre- and post-implementation skin condition documentation were compared by clinician type, and post-implementation IADSI scores were assessed for agreement using standard and weighted Kappa. Results: Of 89 patients (pre-, n=48 and post-, n=38), mean (standard deviation) age was 72.4±13.7 years and 57.3% had IAD. Mean IADSI score was 13.2 (standard deviation: 10.5; range: 0–52), reflecting pink intact skin. Post-implementation, skin documentation between clinicians was more likely to match, from 35.4 to 84.2%, p<0.001. Post-implementation, after controlling for age, gender and race, the odds ration (OR) of matched documentation between clinicians was 5.80 ([95% confidence interval: 1.8, 18.6], p=0.003) compared with pre-implementation. In the post-implementation period, standard Kappas for agreement in clinical nurse-wound expert documentation in the lower back/buttocks/upper thigh areas ranged from 0.82 to 1.0, reflecting very good agreement. Weighted kappas ranged from 0.76 to 1.0, also reflecting good to very good agreement. Conclusion: Implementation of an IADSI assessment instrument improved accuracy of IAD documentation.

scholarly journals Comparison of Above-Water Seabird and TriOS Radiometers along an Atlantic Meridional Transect

2020 ◽  
Vol 12 (10) ◽  
pp. 1669
Author(s):  
Krista Alikas ◽  
Viktor Vabson ◽  
Ilmar Ansko ◽  
Gavin H. Tilstone ◽  
Giorgio Dall’Olmo ◽  
...  
Keyword(s):  
State Of The Art ◽  
Ocean Color ◽  
Percentage Difference ◽  
Wide Range ◽  
Before And After ◽  
Reference Measurements ◽  
Satellite Ocean Color ◽  
Good Agreement

The Fiducial Reference Measurements for Satellite Ocean Color (FRM4SOC) project has carried out a range of activities to evaluate and improve the state-of-the-art in ocean color radiometry. This paper described the results from a ship-based intercomparison conducted on the Atlantic Meridional Transect 27 from 23rd September to 5th November 2017. Two different radiometric systems, TriOS-Radiation Measurement Sensor with Enhanced Spectral resolution (RAMSES) and Seabird-Hyperspectral Surface Acquisition System (HyperSAS), were compared and operated side-by-side over a wide range of Atlantic provinces and environmental conditions. Both systems were calibrated for traceability to SI (Système international) units at the same optical laboratory under uniform conditions before and after the field campaign. The in situ results and their accompanying uncertainties were evaluated using the same data handling protocols. The field data revealed variability in the responsivity between TRiOS and Seabird sensors, which is dependent on the ambient environmental and illumination conditions. The straylight effects for individual sensors were mostly within ±3%. A near infra-red (NIR) similarity correction changed the water-leaving reflectance (ρw) and water-leaving radiance (Lw) spectra significantly, bringing also a convergence in outliers. For improving the estimates of in situ uncertainty, it is recommended that additional characterization of radiometers and environmental ancillary measurements are undertaken. In general, the comparison of radiometric systems showed agreement within the evaluated uncertainty limits. Consistency of in situ results with the available Sentinel-3A Ocean and Land Color Instrument (OLCI) data in the range from (400…560) nm was also satisfactory (−8% < Mean Percentage Difference (MPD) < 15%) and showed good agreement in terms of the shape of the spectra and absolute values.

scholarly journals Characterization of the Resistance and Force of a Carbon Nanotube/Metal Side Contact by Nanomanipulation

Scanning ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Ning Yu ◽  
Masahiro Nakajima ◽  
Qing Shi ◽  
Zhan Yang ◽  
Huaping Wang ◽  
...  
Keyword(s):  
Contact Resistance ◽  
Contact Force ◽  
Contact Area ◽  
Field Effect Transistors ◽  
Influence Factors ◽  
Contact Length ◽  
Before And After ◽  
Negative Exponential ◽  
Good Agreement

A high contact resistance restricts the application of carbon nanotubes (CNTs) in fabrication of field-effect transistors (FETs). Thus, it is important to decrease the contact resistance and investigate the critical influence factors such as the contact length and contact force. This study uses nanomanipulation to characterize both the resistance and the force at a CNT/Au side-contact interface inside a scanning electron microscopy (SEM). Two-terminal CNT manipulation methods, and models for calculating the resistance and force at contact area, are proposed to guide the measurement experiments of a total resistance and a cantilever’s elastic deformation. The experimental results suggest that the contact resistance of CNT/Au interface is large (189.5 kΩ) when the van der Waals force (282.1 nN) dominates the contact force at the interface. Electron-beam-induced deposition (EBID) is then carried out to decrease the contact resistance. After depositing seven EBID points, the resistance is decreased to 7.5 kΩ, and the force increases to 1339.8 nN at least. The resistance and force at the contact area where CNT was fixed exhibit a negative exponential correlation before and after EBID. The good agreement of this correlation with previous reports validates the proposed robotic system and methods for characterizing the contact resistance and force.

scholarly journals Tropospheric ozone profiles by DIAL at Maïdo Observatory (Reunion Island): system description, instrumental performance and result comparison with ozone external data set

2017 ◽  
Vol 10 (9) ◽  
pp. 3359-3373 ◽  
Author(s):  
Valentin Duflot ◽  
Jean-Luc Baray ◽  
Guillaume Payen ◽  
Nicolas Marquestaut ◽  
Francoise Posny ◽  
...  
Keyword(s):  
Current System ◽  
Atmospheric Composition ◽  
Integration Time ◽  
Data Sets ◽  
Buffer Gas ◽  
Reunion Island ◽  
Data Set ◽  
Upper Troposphere ◽  
Réunion Island ◽  
Good Agreement

Abstract. In order to recognize the importance of ozone (O3) in the troposphere and lower stratosphere in the tropics, a DIAL (differential absorption lidar) tropospheric O3 lidar system (LIO3TUR) was developed and installed at the Université de la Réunion campus site (close to the sea) on Reunion Island (southern tropics) in 1998. From 1998 to 2010, it acquired 427 O3 profiles from the low to the upper troposphere and has been central to several studies. In 2012, the system was moved up to the new Maïdo Observatory facility (2160 m a.m.s.l. – metres above mean sea level) where it started operation in February 2013. The current system (LIO3T) configuration generates a 266 nm beam obtained with the fourth harmonic of a Nd:YAG laser sent into a Raman cell filled up with deuterium (using helium as buffer gas), generating the 289 and 316 nm beams to enable the use of the DIAL method for O3 profile measurements. The optimal range for the actual system is 6–19 km a.m.s.l., depending on the instrumental and atmospheric conditions. For a 1 h integration time, vertical resolution varies from 0.7 km at 6 km a.m.s.l. to 1.3 km at 19 km a.m.s.l., and mean uncertainty within the 6–19 km range is between 6 and 13 %. Comparisons with eight electrochemical concentration cell (ECC) sondes simultaneously launched from the Maïdo Observatory show good agreement between data sets with a 6.8 % mean absolute relative difference (D) between 6 and 17 km a.m.s.l. (LIO3T lower than ECC). Comparisons with 37 ECC sondes launched from the nearby Gillot site during the daytime in a ±24 h window around lidar shooting result in a 9.4 % D between 6 and 19 km a.m.s.l. (LIO3T lower than ECC). Comparisons with 11 ground-based Network for Detection of Atmospheric Composition Change (NDACC) Fourier transform infrared (FTIR) spectrometer measurements acquired during the daytime in a ±24 h window around lidar shooting show good agreement between data sets with a D of 11.8 % for the 8.5–16 km partial column (LIO3T higher than FTIR), and comparisons with 39 simultaneous Infrared Atmospheric Sounding Interferometer (IASI) observations over Reunion Island show good agreement between data sets with a D of 11.3 % for the 6–16 km partial column (LIO3T higher than IASI). ECC, LIO3TUR and LIO3T O3 monthly climatologies all exhibit the same range of values and patterns. In particular, the Southern Hemisphere biomass burning seasonal enhancement and the ozonopause altitude decrease in late austral winter–spring, as well as the sign of deep convection bringing boundary layer O3-poor air masses up to the middle–upper troposphere in late austral summer, are clearly visible in all data sets.

scholarly journals Intercomparison of stratospheric temperature profiles from a ground-based microwave radiometer with other techniques

2017 ◽  
Author(s):  
Francisco Navas-Guzmán ◽  
Niklaus Kämpfer ◽  
Franziska Schranz ◽  
Wolfgang Steinbrecht ◽  
Alexander Haefele
Keyword(s):  
Microwave Radiometer ◽  
Temperature Profiles ◽  
Stratospheric Temperature ◽  
Accuracy And Precision ◽  
Before And After ◽  
The Mean ◽  
Standard Deviations ◽  
Rayleigh Lidar ◽  
Clear Change ◽  
Good Agreement

Abstract. In this work the stratospheric performance of a relatively new microwave temperature radiometer (TEMPERA) has been evaluated. With this goal almost three years of temperature measurements (January 2015–September 2016) from TEMPERA radiometer were intercompared with the measurements from different techniques as radiosondes, MLS satellite and Rayleigh lidar. This intercomparison campaign was carried out at the aerological station of MeteoSwiss at Payerne (Switzerland). In addition, the temperature profiles from TEMPERA were used to validate the temperature outputs from SD-WACCM model. The results showed in general a very good agreement between TEMPERA and the different instruments and the model with a high correlation (higher than 0.9) in the temperature evolution at different altitudes between TEMPERA and the different datasets. An annual pattern was observed in the stratospheric temperature with in general higher temperatures in summer than in winter and with a higher variability during wintertime. A clear change in the tendency of the temperature deviations was detected in summer 2015 which was due to the repair of an attenuator in the TEMPERA spectrometer. The mean and the standard deviations of the temperature deviations between TEMPERA and the different measurements were calculated for two periods (before and after the reparation) in order to quantify the accuracy and precision of this radiometer along these almost three years. The results showed absolute biases and standard deviations lower than 2 K for most of the altitudes and comparisons proved the good performance of TEMPERA to measure the temperature in the stratosphere.

scholarly journals Plackett–Burman Combined with Box–Behnken to Optimize the Medium of Fermented Tremella Polysaccharide and Compare the Characteristics before and after Optimization

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Xia Ma ◽  
Meng Yang ◽  
Yan He ◽  
Chenglinang Li ◽  
Chuntao Zhai
Keyword(s):  
Monosaccharide Composition ◽  
Fermentation Medium ◽  
Surface Method ◽  
Before And After ◽  
Acid Polysaccharide ◽  
Burman Design ◽  
Potato Extract ◽  
Plackett Burman Design ◽  
Good Agreement

The purpose of this study was to improve the yield of fermented Tremella polysaccharide (FTP) by optimizing the medium and to explore the effect of optimization on the structure. In this paper, the Plackett–Burman design and response surface method were used to optimize the fermentation medium of Tremella spore GT2# for FTP production. The results of the Plackett–Burman design showed that potato extract, glucose, and peptone were the main factors. The Box–Behnken experiment and regression analysis determined that the optimal concentrations of potato extract, glucose, and peptone were 22.01%, 29.38 g/L, and 2.61 g/L, respectively. After optimization, the fermentation period shortened from 5 days to 3 days, and the yield of FTP increased from 10.75 g/L to 12.50 g/L, which was in good agreement with the predicted value (12.36 g/L). Characterization of FTP obtained before and after optimization was carried out, and the results showed that medium optimization had significant effects on the primary structure of FTP, including molecular weight, monosaccharide composition, and proportion. After optimization, the content of acid polysaccharide increased, and the glycoside bonds changed from a-configuration to ß-configuration.

scholarly journals The diurnal variation in stratospheric ozone from the MACC reanalysis, the ERA-Interim reanalysis, WACCM and Earth observation data: characteristics and intercomparison

2014 ◽  
Vol 14 (23) ◽  
pp. 32667-32708 ◽  
Author(s):  
A. Schanz ◽  
K. Hocke ◽  
N. Kämpfer ◽  
S. Chabrillat ◽  
A. Inness ◽  
...  
Keyword(s):  
Diurnal Variation ◽  
High Latitude ◽  
Transport Model ◽  
Stratospheric Ozone ◽  
Atmospheric Composition ◽  
Atmospheric Tides ◽  
Valuable Insight ◽  
Observation Data ◽  
Free Running ◽  
Good Agreement

Abstract. In this study we compare the diurnal variation in stratospheric ozone derived from free-running simulations of the Whole Atmosphere Community Climate Model (WACCM) and from reanalysis data of the atmospheric service MACC (Monitoring Atmospheric Composition and Climate) which both use a similar stratospheric chemistry module. We find good agreement between WACCM and the MACC reanalysis for the diurnal ozone variation in the high-latitude summer stratosphere based on photochemistry. In addition, we consult the ozone data product of the ERA-Interim reanalysis. The ERA-Interim reanalysis ozone system with its long-term ozone parametrization can not capture these diurnal variations in the upper stratosphere that are due to photochemistry. The good dynamics representations, however, reflects well dynamically induced ozone variations in the lower stratosphere. For the high-latitude winter stratosphere we describe a novel feature of diurnal variation in ozone where changes of up to 46.6% (3.3 ppmv) occur in monthly mean data. For this effect good agreement between the ERA-Interim reanalysis and the MACC reanalysis suggest quite similar diurnal advection processes of ozone. The free-running WACCM model seriously underestimates the role of diurnal advection processes at the polar vortex at the two tested resolutions. The intercomparison of the MACC reanalysis and the ERA-Interim reanalysis demonstrates how global reanalyses can benefit from a chemical representation held by a chemical transport model. The MACC reanalysis provides an unprecedented description of the dynamics and photochemistry of the diurnal variation of stratospheric ozone which is of high interest for ozone trend analysis and research on atmospheric tides. We confirm the diurnal variation in ozone at 5 hPa by observations of the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) experiment and selected sites of the Network for Detection of Atmospheric Composition Change (NDACC). The latter give valuable insight even to diurnal variation of ozone in the polar winter stratosphere.

scholarly journals Intercomparison of stratospheric temperature profiles from a ground-based microwave radiometer with other techniques

2017 ◽  
Vol 17 (22) ◽  
pp. 14085-14104 ◽  
Author(s):  
Francisco Navas-Guzmán ◽  
Niklaus Kämpfer ◽  
Franziska Schranz ◽  
Wolfgang Steinbrecht ◽  
Alexander Haefele
Keyword(s):  
Microwave Radiometer ◽  
Data Sets ◽  
Temperature Profiles ◽  
Stratospheric Temperature ◽  
Accuracy And Precision ◽  
Before And After ◽  
Standard Deviations ◽  
Rayleigh Lidar ◽  
Clear Change ◽  
Good Agreement

Abstract. In this work the stratospheric performance of a relatively new microwave temperature radiometer (TEMPERA) has been evaluated. With this goal in mind, almost 3 years of temperature measurements (January 2014–September 2016) from the TEMPERA radiometer were intercompared with simultaneous measurements from other techniques: radiosondes, MLS satellite and Rayleigh lidar. This intercomparison campaign was carried out at the aerological station of MeteoSwiss at Payerne (Switzerland). In addition, the temperature profiles from TEMPERA were used to validate the temperature outputs from the SD-WACCM model. The results showed in general a very good agreement between TEMPERA and the different instruments and the model, with a high correlation (higher than 0.9) in the temperature evolution at different altitudes between TEMPERA and the different data sets. An annual pattern was observed in the stratospheric temperature with generally higher temperatures in summer than in winter and with a higher variability during winter. A clear change in the tendency of the temperature deviations was detected in summer 2015, which was due to the repair of an attenuator in the TEMPERA spectrometer. The mean and the standard deviations of the temperature differences between TEMPERA and the different measurements were calculated for two periods (before and after the repair) in order to quantify the accuracy and precision of this radiometer over the campaign period. The results showed absolute biases and standard deviations lower than 2 K for most of the altitudes. In addition, comparisons proved the good performance of TEMPERA in measuring the temperature in the stratosphere.

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