scholarly journals Empirical Assessment Tool for Bathymetry, Flow Velocity and Salinity in Estuaries Based on Tidal Amplitude and Remotely-Sensed Imagery

2018 ◽  
Vol 10 (12) ◽  
pp. 1915 ◽  
Author(s):  
Jasper Leuven ◽  
Steye Verhoeve ◽  
Wout van Dijk ◽  
Sanja Selaković ◽  
Maarten Kleinhans
Keyword(s):  
Flow Velocity ◽  
Assessment Tool ◽  
Numerical Models ◽  
High Water ◽  
Remotely Sensed ◽  
Channel Width ◽  
Tidal Amplitude ◽  
Intertidal Area ◽  
Cross Sectional ◽  
Remotely Sensed Imagery

Hydromorphological data for many estuaries worldwide is scarce and usually limited to offshore tidal amplitude and remotely-sensed imagery. In many projects, information about morphology and intertidal area is needed to assess the effects of human interventions and rising sea-level on the natural depth distribution and on changing habitats. Habitat area depends on the spatial pattern of intertidal area, inundation time, peak flow velocities and salinity. While numerical models can reproduce these spatial patterns fairly well, their data need and computational costs are high and for each case a new model must be developed. Here, we present a Python tool that includes a comprehensive set of relations that predicts the hydrodynamics, bed elevation and the patterns of channels and bars in mere seconds. Predictions are based on a combination of empirical relations derived from natural estuaries, including a novel predictor for cross-sectional depth distributions, which is dependent on the along-channel width profile. Flow velocity, an important habitat characteristic, is calculated with a new correlation between depth below high water level and peak tidal flow velocity, which was based on spatial numerical modelling. Salinity is calculated from estuarine geometry and flow conditions. The tool only requires an along-channel width profile and tidal amplitude, making it useful for quick assessments, for example of potential habitat in ecology, when only remotely-sensed imagery is available.

scholarly journals Modelling Built-Settlements between Remotely-Sensed Observations

2019 ◽  
Author(s):  
Jeremiah J. Nieves ◽  
Alessandro Sorichetta ◽  
Catherine Linard ◽  
Maksym Bondarenko ◽  
Jessica Steele ◽  
...  
Keyword(s):  
Remotely Sensed ◽  
Atmospheric Conditions ◽  
Modeling Framework ◽  
Time Step ◽  
Cross Sectional ◽  
Remotely Sensed Imagery ◽  
Flexible Modeling ◽  
Modelling Framework ◽  
Equal Chance ◽  
Spatio Temporal

Mapping settlement extents at the annual time step has a wide variety of applications in demography, public health, sustainable development, and many other fields. Recently, while more multitemporal urban feature or human settlement datasets have become available, issues still exist in remotely-sensed imagery due to coverage, adverse atmospheric conditions, and expenses involved in producing such feature sets. These challenges make it difficult to increase temporal coverage while maintaining high fidelity in the spatial resolution. Here we demonstrate an interpolative and flexible modeling framework for producing annual built-settlement extents. We use a combined technique of random forest and spatio-temporal dasymetric modeling with open source subnational data to produce annual 100m x 100m resolution binary settlement maps in four test countries of varying environmental and developmental contexts for test periods of five-year gaps. We find that in the majority of years, across all study areas, the model correctly identified between 85-99% of pixels that transition to built-settlement. Additionally, with few exceptions, the model substantially out performed a model that gave every pixel equal chance of transitioning to the category “built” in each year. This modelling framework shows strong promise for filling gaps in cross-sectional urban feature datasets derived from remotely-sensed imagery, provide a base upon which to create future built/settlement extent projections, and further explore the relationships between built area and population dynamics.

scholarly journals Modelling Built-Settlements between Remotely-Sensed Observations

2018 ◽  
Author(s):  
Jeremiah J. Nieves ◽  
Alessandro Sorichetta ◽  
Catherine Linard ◽  
Maksym Bondarenko ◽  
Jessica Steele ◽  
...  
Keyword(s):  
Remotely Sensed ◽  
Atmospheric Conditions ◽  
Modeling Framework ◽  
Time Step ◽  
Cross Sectional ◽  
Remotely Sensed Imagery ◽  
Flexible Modeling ◽  
Modelling Framework ◽  
Equal Chance ◽  
Spatio Temporal

Mapping settlement extents at the annual time step has a wide variety of applications in demography, public health, sustainable development, and many other fields. Recently, while more multitemporal urban feature or human settlement datasets have become available, issues still exist in remotely-sensed imagery due to coverage, adverse atmospheric conditions, and expenses involved in producing such feature sets. These challenges make it difficult to increase temporal coverage while maintaining high fidelity in the spatial resolution. Here we demonstrate an interpolative and flexible modeling framework for producing annual built-settlement extents. We use a combined technique of random forest and spatio-temporal dasymetric modeling with open source subnational data to produce annual 100m x 100m resolution binary settlement maps in four test countries of varying environmental and developmental contexts for test periods of five-year gaps. We find that in the majority of years, across all study areas, the model correctly identified between 85-99% of pixels that transition to built-settlement. Additionally, with few exceptions, the model substantially out performed a model that gave every pixel equal chance of transitioning to the category “built” in each year. This modelling framework shows strong promise for filling gaps in cross-sectional urban feature datasets derived from remotely-sensed imagery, provide a base upon which to create future built/settlement extent projections, and further explore the relationships between built area and population dynamics.

scholarly journals Annually Modelling Built-settlements between Remotely-sensed Observations Using Relative Changes in Subnational Populations and Lights at Night

2019 ◽  
Author(s):  
Jeremiah J. Nieves ◽  
Alessandro Sorichetta ◽  
Catherine Linard ◽  
Maksym Bondarenko ◽  
Jessica Steele ◽  
...  
Keyword(s):  
Remotely Sensed ◽  
Atmospheric Conditions ◽  
Modeling Framework ◽  
Time Step ◽  
Cross Sectional ◽  
Remotely Sensed Imagery ◽  
Flexible Modeling ◽  
Modelling Framework ◽  
Equal Chance ◽  
Spatio Temporal

Mapping settlement extents at the annual time step has a wide variety of applications in demography, public health, sustainable development, and many other fields. Recently, while more multitemporal urban feature or human settlement datasets have become available, issues still exist in remotely-sensed imagery due to coverage, adverse atmospheric conditions, and expenses involved in producing such feature sets. These challenges make it difficult to increase temporal coverage while maintaining high fidelity in the spatial resolution. Here we demonstrate an interpolative and flexible modeling framework for producing annual built-settlement extents. We use a combined technique of random forest and spatio-temporal dasymetric modeling with open source subnational data to produce annual 100m x 100m resolution binary settlement maps in four test countries of varying environmental and developmental contexts for test periods of five-year gaps. We find that in the majority of years, across all study areas, the model correctly identified between 85-99% of pixels that transition to built-settlement. Additionally, with few exceptions, the model substantially out performed a model that gave every pixel equal chance of transitioning to the category “built” in each year. This modelling framework shows strong promise for filling gaps in cross-sectional urban feature datasets derived from remotely-sensed imagery, provide a base upon which to create future built/settlement extent projections, and further explore the relationships between built area and population dynamics.

The association between dietary inflammatory index and risk of central obesity in adults: An updated systematic review and meta-analysis

2020 ◽  
Vol 90 (5-6) ◽  
pp. 535-552 ◽  
Author(s):  
Mahdieh Abbasalizad Farhangi ◽  
Mahdi Vajdi
Keyword(s):  
Systematic Review ◽  
Observational Studies ◽  
Central Obesity ◽  
Assessment Tool ◽  
Weighted Mean Difference ◽  
Meta Analysis ◽  
Dietary Factors ◽  
Cross Sectional ◽  
Inflammatory Status ◽  
Obesity Indices

Abstract. Backgrounds: Central obesity, as a pivotal component of metabolic syndrome is associated with numerous co-morbidities. Dietary factors influence central obesity by increased inflammatory status. However, recent studies didn’t evaluate the association between central obesity and dietary inflammation index (DII®) that give score to dietary factors according to their inflammatory potential. In the current systematic review and meta-analysis, we summarized the studies that investigated the association between DII® with central obesity indices in the general populations. Methods: In a systematic search from PubMed, SCOPUS, Web of Sciences and Cochrane electronic databases, we collected relevant studies written in English and published until 30 October 2019. The population of included studies were apparently healthy subjects or individuals with obesity or obesity-related diseases. Observational studies that evaluated the association between DII® and indices of central obesity including WC or WHR were included. Results: Totally thirty-two studies were included; thirty studies were cross-sectional and two were cohort studies with 103071 participants. Meta-analysis of observational studies showed that higher DII® scores were associated with 1.81 cm increase in WC (Pooled weighted mean difference (WMD) = 1.813; CI: 0.785–2.841; p = 0.001). Also, a non-significant increase in the odds of having higher WC (OR = 1.162; CI: 0.95–1.43; p = 0.154) in the highest DII category was also observed. In subgroup analysis, the continent, dietary assessment tool and gender were the heterogeneity sources. Conclusion: The findings proposed that adherence to diets with high DII® scores was associated with increased WC. Further studies with interventional designs are necessary to elucidate the causality inference between DII® and central obesity indices.

Remotely sensed imagery revealing the effects of hurricanes Gustav and Ike on coastal Louisiana

Data Series ◽  
10.3133/ds566 ◽  
2010 ◽  
Author(s):  
John A. Barras ◽  
John C. Brock ◽  
Robert A. Morton ◽  
Laurinda J. Travers
Keyword(s):  
Remotely Sensed ◽  
Remotely Sensed Imagery ◽  
Coastal Louisiana

About time lag and some morphometric characteristics of streams of the forest zone

2016 ◽  
Author(s):  
Н.А. Белоногова ◽  
А.Ю. Виноградов ◽  
Т.А. Виноградова ◽  
Д.А. Догановский ◽  
А.Н. Кондратьев ◽  
...  
Keyword(s):  
Flow Velocity ◽  
Average Rate ◽  
Time Lag ◽  
High Water ◽  
Spatial And Temporal Variability ◽  
Forest Zone ◽  
Average Flow Velocity ◽  
Small Watersheds ◽  
Maximum Water ◽  
General Movement

Расчет максимальных расходов воды дождевых паводков на малых водосборах, в целях эффективного проектирования лесохозяйственных инженерных дорожных сооружений, представляет собой весьма сложную задачу вследствие отсутствия достаточных наблюдений за характеристиками дождевого стока. Кроме того, характеристики дождевого стока и определяющие их факторы обладают большой пространственной и временной изменчивостью, что еще больше затрудняет их определение. Рекомендуемая действующими нормативами методика определения максимального дождевого стока, как показывает практический опыт, нуждается в незамедлительном редактировании с точки зрения сопоставления размерностей и правильности ссылок. Особое внимание в статье уделено определению времени добегания, включенного в расчетные формулы в качестве определяющего параметра. В настоящее время понятие «время добегания» однозначно не определено. В связи с тем, что наполненность русел рек имеет высокую пространственную и временную неоднородность и изменчивость, общее движение воды в створе проектируемого инженерного сооружения можно представить достаточно упорядоченным и единообразным, с практически постоянной паводковой средней скоростью. На основе натурных наблюдений известно, что во время паводка средняя по сечению скорость потока сохраняется постоянной в пределах верхней десятипроцентной части амплитуды уровней воды. Такие данные с конца 70-х годов не публикуются. Обработка имеющихся данных говорит о том, что существует незначительное увеличение скоростей течения с ростом площади бассейнов. Поэтому предлагается принять время добегания τi, определенное по характерным отрезкам руслового пути от исследуемого створа до истока с помощью интерполяции измеренных на гидрометрических постах данных по скоростям течения. The calculation of the maximum water flow during the high water, especially on small watersheds, in order to effectively design engineering of road structures, is a very difficult task due to the lack of sufficient observations. In addition, the characteristics of rainfall, and their determinants have a high spatial and temporal variability, which further complicates their definition. Currently recommended method of determining the characteristics of the maximum rainwater, as the experience, needs immediate clarification of dimensions and verify links. Particular attention is paid to the calculation of lag time, included in the formulas as the defining parameter. Fullness riverbeds has high spatial and temporal heterogeneity and variability. The general movement of water in the closing alignment ordered and uniform. The average rate of slightly increased or decreased depending on the dryness of the season. Each cross-section corresponds to the value of average flow velocity. These data are from the late 70-ies are not published. Processing of existing data suggests that there is a slight increase in the flow velocity with increasing basin areas. Therefore, as a constant time lag is invited to take the time determined by the characteristic segments of the channel path from the source to the alignment of the test.

Map-guided interpretation of remotely-sensed imagery

1980 ◽  
Author(s):  
J. M. Tenenbaum ◽  
H. G. Barrow ◽  
R. C. Bolles ◽  
M. A. Fischler ◽  
H. C. Wolf
Keyword(s):  
Remotely Sensed ◽  
Remotely Sensed Imagery

scholarly journals Chinesisation, adaptation and validation of the Chelsea Critical Care Physical Assessment Tool in critically ill patients: a cross-sectional observational study

BMJ Open ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. e045550
Author(s):  
Zhigang Zhang ◽  
Guoqiang Wang ◽  
Yuchen Wu ◽  
Jin Guo ◽  
Nannan Ding ◽  
...  
Keyword(s):  
Critical Care ◽  
Observational Study ◽  
Critically Ill ◽  
Content Validity ◽  
Assessment Tool ◽  
Western China ◽  
Validity Index ◽  
Cross Sectional ◽  
Physical Assessment ◽  
Content Validity Index

PurposeTo translate and adapt the Chelsea Critical Care Physical Assessment Tool (CPAx) into Chinese version (‘CPAx-Chi’), test the reliability and validity of CPAx-Chi, and verify the cut-off point for the diagnosis of intensive care unit-acquired weakness (ICU-AW).Study designCross-sectional observational study.MethodsForward and back translation, cross-cultural adaptation and pretesting of CPAx into CPAx-Chi were based on the Brislin model. Participants were recruited from the general ICU of five third-grade class-A hospitals in western China. Two hundred critically ill adult patients (median age: 53 years; 64% men) with duration of ICU stay ≥48 hours and Glasgow Coma Scale ≥11 were included in this study. Two researchers simultaneously and independently assessed eligible patients using the Medical Research Council Muscle Score (MRC-Score) and CPAx-Chi.ResultsThe content validity index of items was 0.889. The content validity index of scale was 0.955. Taking the MRC-Score scale as standard, the criterion validity of CPAx-Chi was r=0.758 (p<0.001) for researcher A, and r=0.65 (p<0.001) for researcher B. Cronbach’s α was 0.939. The inter-rater reliability was 0.902 (p<0.001). The area under the receiver operating characteristic curves of CPAx-Chi for diagnosing ICU-AW based on MRC-Score ≤48 were 0.899 (95% CI 0.862 to 1.025) and 0.874 (95% CI 0.824 to 0.925) for researcher B. The best cut-off point for CPAx-Chi for the diagnosis of ICU-AW was 31.5. The sensitivity was 87% and specificity was 77% for researcher A, whereas it was 0.621, 31.5, 75% and 87% for researcher B, respectively. The consistency was high when taking CPAx-Chi ≤31 and MRC-Score ≤48 as the cut-off points for the diagnosis of ICU-AW. Cohen’s kappa=0.845 (p=0.02) in researcher A and 0.839 (p=0.04) for researcher B.ConclusionsCPAx-Chi demonstrated content validity, criterion-related validity and reliability. CPAx-Chi showed the best accuracy in assessment of patients at risk of ICU-AW with good sensitivity and specificity at a recommended cut-off of 31.

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