scholarly journals An extended Benthic Quality Index for assessment of lake profundal macroinvertebrates: addition of indicator taxa by multivariate ordination and weighted averaging

2014 ◽  
Vol 33 (3) ◽  
pp. 995-1007 ◽  
Author(s):  
Jussi Jyväsjärvi ◽  
Jukka Aroviita ◽  
Heikki Hämäläinen
Keyword(s):  
Quality Index ◽  
Weighted Averaging ◽  
Indicator Taxa ◽  
Multivariate Ordination

scholarly journals Enhancing the consistency of spaceborne and ground-based radar comparisons by using beam blockage fraction as a quality filter

2018 ◽  
Vol 11 (9) ◽  
pp. 5223-5236 ◽  
Author(s):  
Irene Crisologo ◽  
Robert A. Warren ◽  
Kai Mühlbauer ◽  
Maik Heistermann
Keyword(s):  
Quality Index ◽  
Weighted Average ◽  
Tropical Rainfall Measuring Mission ◽  
Radar Data ◽  
Weighted Averaging ◽  
Precipitation Measurement ◽  
Radar Calibration ◽  
Global Precipitation Measurement ◽  
Global Precipitation ◽  
Spaceborne Radar

Abstract. We explore the potential of spaceborne radar (SR) observations from the Ku-band precipitation radars onboard the Tropical Rainfall Measuring Mission (TRMM) and Global Precipitation Measurement (GPM) satellites as a reference to quantify the ground radar (GR) reflectivity bias. To this end, the 3-D volume-matching algorithm proposed by Schwaller and Morris (2011) is implemented and applied to 5 years (2012–2016) of observations. We further extend the procedure by a framework to take into account the data quality of each ground radar bin. Through these methods, we are able to assign a quality index to each matching SR–GR volume, and thus compute the GR calibration bias as a quality-weighted average of reflectivity differences in any sample of matching GR–SR volumes. We exemplify the idea of quality-weighted averaging by using the beam blockage fraction as the basis of a quality index. As a result, we can increase the consistency of SR and GR observations, and thus the precision of calibration bias estimates. The remaining scatter between GR and SR reflectivity as well as the variability of bias estimates between overpass events indicate, however, that other error sources are not yet fully addressed. Still, our study provides a framework to introduce any other quality variables that are considered relevant in a specific context. The code that implements our analysis is based on the wradlib open-source software library, and is, together with the data, publicly available to monitor radar calibration or to scrutinize long series of archived radar data back to December 1997, when TRMM became operational.

scholarly journals Enhancing the consistency of spaceborne and ground-based radar comparisons by using quality filters

2018 ◽  
Author(s):  
Irene Crisologo ◽  
Robert Warren ◽  
Kai Mühlbauer ◽  
Maik Heistermann
Keyword(s):  
Quality Index ◽  
Weighted Average ◽  
Early Warning Systems ◽  
Radar Data ◽  
Rain Gauge ◽  
The Philippines ◽  
Weighted Averaging ◽  
Torrential Rainfall ◽  
Radar Calibration ◽  
3D Volume

Abstract. Coinciding monsoon and typhoon seasons in the Philippines cause torrential rainfall, and associated hazards such as flooding and landslides. While early warning systems require accurate radar-based rainfall estimates, low-density rain gauge networks in the Philippines make it challenging to monitor the calibration of the ground-based radars (GRs). As an alternative, we explore the potential of spaceborne radar (SR) observations from the Ku-band precipitation radars on board the TRMM and GPM satellites as a reference to quantify the calibration bias of an S-band GR in the Philippines. To this end, the 3D volume-matching algorithm proposed by Schwaller and Morris (2009) is implemented and applied to five years (2012–2016) of observations. We further extend the procedure by a framework to take into account the data quality of each ground radar bin. Through these methods, we are able to assign a quality index to each matching SR-GR volume, and thus compute the GR calibration bias as a quality-weighted average of reflectivity differences in any sample of matching GR-SR volumes. We exemplify the idea of quality-weighted averaging by using the beam blockage fraction as a basis of a quality index. As a result, we can increase the consistency of SR and GR observations, and thus the precision of calibration bias estimates. The remaining scatter between GR and SR reflectivity, as well as the variability of bias estimates between overpass events indicate, however, that other error sources are not yet fully addressed. Still, our study provides a framework to introduce any other quality variables that are considered relevant in a specific context. The code that implements our analysis is based on the open source software library wradlib, and is, together with the data, publicly available to monitor radar calibration, or to scrutinize long series of archived radar data back to December 1997, when TRMM became operational.

The Effect of Kalman-Weighted Averaging and Artifact Rejection on Residual Noise During Auditory Brainstem Response Testing

2019 ◽  
Vol 28 (1) ◽  
pp. 114-124
Author(s):  
Linda W. Norrix ◽  
Julie Thein ◽  
David Velenovsky
Keyword(s):  
Repeated Measures ◽  
Auditory Brainstem ◽  
Weighted Averaging ◽  
Auditory Brainstem Responses ◽  
Residual Noise ◽  
Electrophysiological Recordings ◽  
Artifact Rejection ◽  
Brainstem Response ◽  
Active Motor ◽  
Averaging Time

Purpose Low residual noise (RN) levels are critically important when obtaining electrophysiological recordings of threshold auditory brainstem responses. In this study, we examine the effectiveness and efficiency of Kalman-weighted averaging (KWA) implemented on the Vivosonic Integrity System and artifact rejection (AR) implemented on the Intelligent Hearing Systems SmartEP system for obtaining low RN levels. Method Sixteen adults participated. Electrophysiological measures were obtained using simultaneous recordings by the Vivosonic and Intelligent Hearing Systems for subjects in 2 relaxed conditions and 4 active motor conditions. Three averaging times were used for the relaxed states (1, 1.5, and 3 min) and for the active states (1.5, 3, and 6 min). Repeated-measures analyses of variance were used to examine RN levels as a function of noise reduction strategy (i.e., KWA, AR) and averaging time. Results Lower RN levels were obtained using KWA than AR in both the relaxed and active motor states. Thus, KWA was more effective than was AR under the conditions examined in this study. Using KWA, approximately 3 min of averaging was needed in the relaxed condition to obtain an average RN level of 0.025 μV. In contrast, in the active motor conditions, approximately 6 min of averaging was required using KWA. Mean RN levels of 0.025 μV were not attained using AR. Conclusions When patients are not physiologically quiet, low RN levels are more likely to be obtained and more efficiently obtained using KWA than AR. However, even when using KWA, in active motor states, 6 min of averaging or more may be required to obtain threshold responses. Averaging time needed and whether a low RN level can be attained will depend on the level of motor activity exhibited by the patient.

Homocysteine Levels Show Significant Differences among Mediterranean Dietary Quality Index Variables Compared to Folate and Vitamin B12 Status in Women

2015 ◽  
Vol 85 (3-4) ◽  
pp. 202-210 ◽  
Author(s):  
Ivona Višekruna ◽  
Ivana Rumbak ◽  
Ivana Rumora Samarin ◽  
Irena Keser ◽  
Jasmina Ranilović
Keyword(s):  
Mediterranean Diet ◽  
Diet Quality ◽  
Quality Index ◽  
Fruits And Vegetables ◽  
Reproductive Age ◽  
Dietary Quality ◽  
Vitamin B ◽  
Cross Sectional ◽  
Poor Diet ◽  
The Mediterranean

Abstract. Results of epidemiologic studies and clinical trials have shown that subjects following the Mediterranean diet had lower inflammatory markers such as homocysteine (Hcy). Therefore, the aim of this cross-sectional study was to assess female diet quality with the Mediterranean diet quality index (MDQI) and to determine the correlation between MDQI, homocysteine, folate and vitamin B12 levels in the blood. The study participants were 237 apparently healthy women (96 of reproductive age and 141 postmenopausal) between 25 and 93 years. For each participant, 24-hour dietary recalls for 3 days were collected, MDQI was calculated, and plasma Hcy, serum and erythrocyte folate and vitamin B12 levels were analysed. Total MDQI ranged from 8 to 10 points, which represented a medium-poor diet for the subjects. The strength of correlation using biomarkers, regardless of group type, age, gender and other measured parameters, was ranked from best (0.11) to worst (0.52) for olive oil, fish, fruits and vegetables, grains, and meat, in this order. Hcy levels showed the best response among all markers across all groups and food types. Our study shows significant differences between variables of the MDQI and Hcy levels compared to levels of folate and vitamin B12 in participants with medium-poor diet quality, as evaluated according to MDQI scores.

Quality of Governance at the Communal Level in Poland: an Exploratory Study of the Worst Performer Case From the Opolskie Province

2020 ◽  
Vol 21 (1) ◽  
pp. 22-55
Author(s):  
Bartosz Czepil
Keyword(s):  
Exploratory Study ◽  
Quality Index ◽  
Extreme Case ◽  
Quality Level ◽  
Case Method ◽  
Major Conclusion ◽  
Second Stage ◽  
Quality Of Governance ◽  
Governance Quality

The objective of this paper is an attempt to explain the determinants of the lowest governance quality level in one of the communes of the Opolskie Province, Poland. The first stage of the research consisted in developing a commune-level governance quality index in order to measure the quality of governance in the 60 communes of the Opolskie Province. Subsequently, the commune with the lowest score in the index was qualified for the second stage of the research which was based on the extreme case method. The major conclusion from the research is that the commune leader's governance style which allowed him to hold on to power for many terms of office was responsible for generating low governance quality. Furthermore, the low quality of governance was not only the effect of the governance style but also the strategy aimed at remaining in the commune leader office for many terms.

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