In Situ Polymerized Wicks for Passive Water Management and Humidification of Dry Gases

2019 ◽  
Vol 25 (1) ◽  
pp. 303-309 ◽  
Author(s):  
Daniel G. Strickland ◽  
Juan G. Santiago
Keyword(s):  
Water Management

In situ analysis of water management in operating fuel cells by confocal Raman spectroscopy

2011 ◽  
Vol 13 (5) ◽  
pp. 418-422 ◽  
Author(s):  
P. Huguet ◽  
A. Morin ◽  
G. Gebel ◽  
S. Deabate ◽  
A.K. Sutor ◽  
...  
Keyword(s):  
Water Management ◽  
Raman Spectroscopy ◽  
Fuel Cells ◽  
In Situ Analysis ◽  
Confocal Raman Spectroscopy ◽  
Confocal Raman

scholarly journals Irrigation Events Detection over Intensively Irrigated Grassland Plots Using Sentinel-1 Data

2020 ◽  
Vol 12 (24) ◽  
pp. 4058
Author(s):  
Hassan Bazzi ◽  
Nicolas Baghdadi ◽  
Ibrahim Fayad ◽  
François Charron ◽  
Mehrez Zribi ◽  
...  
Keyword(s):  
Water Management ◽  
Time Series ◽  
Vegetation Index ◽  
Irrigation Schedule ◽  
Threshold Value ◽  
Climatic Conditions ◽  
Irrigated Agriculture ◽  
Sar Image ◽  
Detection Model

Better management of water consumption and irrigation schedule in irrigated agriculture is essential in order to save water resources, especially at regional scales and under changing climatic conditions. In the context of water management, the aim of this study is to monitor irrigation activities by detecting the irrigation episodes at plot scale using the Sentinel-1 (S1) C-band SAR (synthetic-aperture radar) time series over intensively irrigated grassland plots located in the Crau plain of southeast France. The method consisted of assessing the newly developed irrigation detection model (IDM) at plot scale over the irrigated grassland plots. First, four S1-SAR time series acquired from four different S1-SAR acquisitions (different S1 orbits), each at six-day revisit time, were obtained over the study site. Next, the IDM was applied at each available SAR image from each S1-SAR series to obtain an irrigation indicator at each SAR image (no, low, medium, or high irrigation possibility). Then, the irrigation indicators obtained at each image from each S1-SAR time series (four series) were added and combined by threshold value criteria to determine the existence or absence of an irrigation event. Finally, the performance of the IDM for irrigation detection was assessed by comparing the in situ recorded irrigation events at each plot and the detected irrigation events. The results show that using only the VV polarization, 82.4% of the in situ registered irrigation events are correctly detected with an F_score value reaching 73.8%. Less accuracy is obtained using only the VH polarization, where 79.9% of the in situ irrigation events are correctly detected with an F_score of 72.2%. The combined use of the VV and VH polarization showed that 74.1% of the irrigation events are detected with a higher F_score value of 76.4%. The analysis of the undetected irrigation events revealed that, in the presence of very well-developed vegetation cover (normalized difference of vegetation index (NDVI) ≥ 0.8); higher uncertainty in irrigation detection is observed, where 80% of the undetected events correspond to an NDVI value greater than 0.8. The results also showed that small-sized plots encounter more false irrigation detections than large-sized plots certainly because the pixel spacing of S1 data (10 m × 10 m) is not adapted to small size plots. The obtained results prove the efficiency of the S1 C-band data and the IDM for detecting irrigation events at the plot scale, which would help in improving the irrigation water management at large scales especially with availability and global coverage of the S1 product.

In-Situ Measurement in Through-Plane Direction in PEMFC

2009 ◽  
Author(s):  
Kohei Ito ◽  
Sangkun Lee ◽  
Atsushi Yamamoto ◽  
Masaaki Hirano ◽  
Hidetaka Muramatsu ◽  
...  
Keyword(s):  
Water Management ◽  
Sensor Array ◽  
Polymer Electrolyte Membrane ◽  
Cell Voltage ◽  
Gas Diffusion ◽  
Cross Sectional ◽  
Electrolyte Membrane ◽  
Water Behavior ◽  
Plane Direction

Water management is a large issue for putting PEMFC to practical use. Appropriate water management enables us to suppress the drying in PEM (Polymer Electrolyte Membrane) and the flooding in GDL (Gas Diffusion Layer), which degrade the performance of PEMFC. Against the background of importance for the water management, we challenged to develop the measurement method to grasp the water behavior in PEMFC. Especially, we focused on through-plane direction measurement, because the through-plane direction in cell has major role for the transport of mass, heat and electric charge in the cell. We developed the three methods to measure the water in cell directly or indirectly: cross sectional cell: micro NMR-sensor array: micro thermocouple array. These three methods successively captured the distribution of the liquid water in GDL, the water content in PEM and the temperature in cell. The data obtained help us to give the possible mechanism of how the water in cell impacted the cell voltage.

scholarly journals Towards Estimating Land Evaporation at Field Scales Using GLEAM

2018 ◽  
Vol 10 (11) ◽  
pp. 1720 ◽  
Author(s):  
Brecht Martens ◽  
Richard de Jeu ◽  
Niko Verhoest ◽  
Hanneke Schuurmans ◽  
Jonne Kleijer ◽  
...  
Keyword(s):  
Water Management ◽  
Soil Moisture ◽  
High Resolution ◽  
The Netherlands ◽  
Weather Conditions ◽  
Irrigation Scheduling ◽  
In Situ Measurements ◽  
Rainfall Interception ◽  
Interception Loss

The evaporation of water from land into the atmosphere is a key component of the hydrological cycle. Accurate estimates of this flux are essential for proper water management and irrigation scheduling. However, continuous and qualitative information on land evaporation is currently not available at the required spatio-temporal scales for agricultural applications and regional-scale water management. Here, we apply the Global Land Evaporation Amsterdam Model (GLEAM) at 100 m spatial resolution and daily time steps to provide estimates of land evaporation over The Netherlands, Flanders, and western Germany for the period 2013–2017. By making extensive use of microwave-based geophysical observations, we are able to provide data under all weather conditions. The soil moisture estimates from GLEAM at high resolution compare well with in situ measurements of surface soil moisture, resulting in a median temporal correlation coefficient of 0.76 across 29 sites. Estimates of terrestrial evaporation are also evaluated using in situ eddy-covariance measurements from five sites, and compared to estimates from the coarse-scale GLEAM v3.2b, land evaporation from the Satellite Application Facility on Land Surface Analysis (LSA-SAF), and reference grass evaporation based on Makkink’s equation. All datasets compare similarly with in situ measurements and differences in the temporal statistics are small, with correlation coefficients against in situ data ranging from 0.65 to 0.95, depending on the site. Evaporation estimates from GLEAM-HR are typically bounded by the high values of the Makkink evaporation and the low values from LSA-SAF. While GLEAM-HR and LSA-SAF show the highest spatial detail, their geographical patterns diverge strongly due to differences in model assumptions, model parameterizations, and forcing data. The separate consideration of rainfall interception loss by tall vegetation in GLEAM-HR is a key cause of this divergence: while LSA-SAF reports maximum annual evaporation volumes in the Green Heart of The Netherlands, an area dominated by shrubs and grasses, GLEAM-HR shows its maximum in the national parks of the Veluwe and Heuvelrug, both densely-forested regions where rainfall interception loss is a dominant process. The pioneering dataset presented here is unique in that it provides observational-based estimates at high resolution under all weather conditions, and represents a viable alternative to traditional visible and infrared models to retrieve evaporation at field scales.

scholarly journals Trends in Demand of Urban Surface Water Extractions and in Situ Use Functions

2020 ◽  
Vol 34 (15) ◽  
pp. 4943-4958
Author(s):  
E. S. van der Meulen ◽  
N. B. Sutton ◽  
F. H. M. van de Ven ◽  
P. R. van Oel ◽  
H. H. M. Rijnaarts
Keyword(s):  
Water Management ◽  
Surface Water ◽  
Water Use ◽  
Scientific Literature ◽  
Urban Surface ◽  
Urban Water ◽  
Urban Water Management ◽  
Comprehensive Overview ◽  
Waste Products

AbstractScientific literature currently lacks comprehensive understanding of urban surface water use functions. This hampers sound analysis of the demand and potential supply of these functions. This study provides a comprehensive overview of potential use functions, by integrating knowledge from ecosystem services and integrated urban water management fields. Analysis of water-related management plans for Toronto and Amsterdam shows that surface water is currently being used for a variety of functions related to nutrition, energy, water regulation, recreation, symbolic use, transportation and floating buildings. Notably, many use functions involve in situ use, rather than water extractions. Interviewed water managers and spatial planners in both cities expect demand of most use functions to increase by 2040, especially demand for thermal energy extraction, recreation and transportation. Some identified novel demands, such as climate regulation and reuse of waste products from waterway maintenance. Increasing demand is mainly driven by urban growth, climate change and sustainability ambitions. This study found urban surface water uses that are usually not acknowledged in scientific literature on urban water management. This comprehensive overview supports planning, design, and maintenance of urban surface waters, laying the foundation for future research on supply and demand of urban water use functions.

scholarly journals Inspecciones en la gestión del agua de fachadas ventiladas basadas en la evaluación in situ y pruebas de laboratorio = Insights in the water management characteristics of rear-ventilated façades based on on-site assessment and laboratory testing

2017 ◽  
Vol 3 (1) ◽  
pp. 14 ◽  
Author(s):  
María Arce Recatalá ◽  
Soledad García Morales ◽  
Nathan Van den Bossche
Keyword(s):  
Water Management ◽  
Laboratory Testing ◽  
Water Infiltration ◽  
Site Assessment ◽  
Site Analysis ◽  
El Sistema ◽  
Combined Action ◽  
Rain Infiltration ◽  
Wind Pressures

ResumenLas fachadas ventiladas son sistemas de construcción de fachadas contemporáneas, que incorporan funciones para la gestión del agua en su diseño y construcción. Sin embargo, muy a menudo estas funciones para la gestión de agua no funcionan adecuadamente en todo el sistema del recinto debido a un mal diseño de los detalles constructivos, fallas de construcción en la fachada o lagunas en la comprensión de los mecanismos de infiltración de lluvia, causando que el agua penetre en estos sistemas. El objetivo de este trabajo es presentar algunas ideas sobre cómo funcionan las características de gestión del agua de las fachadas ventiladas en todo el recinto del edificio. Posteriormente, se ha probado una maqueta a escala completa en condiciones  de laboratorio. Finalmente, se ha realizado una comparación entre el análisis in situ y los resultados obtenidos en las pruebas de laboratorio, concluyendo que es posible mejorar el comportamiento de gestión del agua de las fachadas ventiladas con la acción combinada de la lluvia y las presiones del viento, si los mecanismos que pueden causar infiltración de agua son bien comprendidosAbstractRear-ventilated façades are contemporary façade construction systems, which incorporate water management features into their design and construction. However, quite often these water management features do not properly work in the whole enclosure syste due to bad design of the constructive details, construction flaws in the façade or gaps in the understanding of the rain infiltration mechanisms causing water to penetrate in these systems. Consequently, the aim of his paper is to present some insights of how the water management features of rear-ventilated façades perform in the whole enclosure system of the building. Subsequently, a full-scale mock-up has been tested in laboratory conditions. Finally, a comparison between the on-site analysis and the results obtained in the laboratory tests has been made, concluding that it is possible to improve the water management performance of rear-ventilated façades to the combined action of wind-driven rain and driving rain wind pressures if the mechanisms that might cause water infiltration are well understood. 

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