In situ real-time optical sensing device for three-dimensional water chemistry surveillance

2015 ◽  
Vol 10 (4) ◽  
pp. 836-845 ◽  
Author(s):  
C.-L. Ng ◽  
T.-B. Koay ◽  
S. Senft-Grupp ◽  
M. Chitre ◽  
H. F. Hemond
Keyword(s):  
Water Chemistry ◽  
Real Time ◽  
Autonomous Underwater Vehicles ◽  
Three Dimensional ◽  
Water Bodies ◽  
Spatiotemporal Variability ◽  
Sample Collection ◽  
Spatial Coverage ◽  
Small Team

Assessing the aquatic chemistry of water bodies through sample collection is labor- and time-intensive with limits on discrete spatial coverage that may not provide a detailed representation of the system. A practical approach is to develop in situ sensors deployed aboard autonomous underwater vehicles (AUVs) for three-dimensional water chemistry mapping. For this purpose, a compact optical instrument (LEDIF) measuring fluorescence, absorbance, and scattering to quantify contaminants and natural substances in water bodies is packaged inside a pressure hull and attached to a highly modular and flexible AUV (Small Team of Autonomous Robotic FISH (STARFISH)). LEDIF-STARFISH was deployed at a reservoir in Singapore for in situ real-time chlorophyll a and turbidity data collection. Locations of potential algal hot spots were observed, providing unprecedented insight into the plankton biomass distribution of the reservoir at different times. The results showcase the instrument's potential in tracking spatiotemporal variability of substances in large water bodies.

The International Soil Moisture Network in assistance of EO soil moisture validation products, services and models

2020 ◽  
Author(s):  
Daniel Aberer ◽  
Irene Himmelbauer ◽  
Lukas Schremmer ◽  
Ivana Petrakovic ◽  
Wouter Dorigo ◽  
...  
Keyword(s):  
Quality Control ◽  
Soil Moisture ◽  
Real Time ◽  
Land Surface ◽  
Measurement Techniques ◽  
European Space Agency ◽  
Web Portal ◽  
Soil Moisture Data ◽  
Spatial Coverage

<p>The International Soil Moisture Network (ISMN, https://ismn.geo.tuwien.ac.at/) is an international cooperation to establish and maintain a unique centralized global data hosting facility, making in situ soil moisture data easily and freely accessible. This database is an essential means for validating and improving global satellite soil moisture products, land surface -, climate- , and hydrological models. </p><p>In situ measurements are crucial to calibrate and validate satellite soil moisture products. For a meaningful comparison with remotely sensed data and reliable validation results, the quality of the reference data is essential. The various independent local and regional in situ networks often do not follow standardized measurement techniques or protocols, collecting their data in different units, at different depths and at various sampling rates. Besides, quality control is rarely applied and accessing the data is often not easy or feasible.</p><p>The ISMN has been created to address the above-mentioned issues and is building a stable base to assist EO products, services and models. Within the ISMN, in situ soil moisture measurements (surface and sub-surface) are collected, harmonized in terms of units and sampling rates, advanced quality control is applied and the data is then stored in a database and made available online, where users can download it for free.</p><p>Founded in 2009, the ISMN has grown to a widely used in situ data source including 61 networks with more than 2600 stations distributed on a global scale and a steadily growing user community > 3200 registered users strong. Time series with hourly timestamps from 1952 – up to near real time are stored in the database and are available through the ISMN web portal, including daily near-real time updates from 6 networks (> 900 stations). With continuous financial support through the European Space Agency (formerly SMOS and IDEAS+ programs, currently QA4EO program), the ISMN evolved into a platform of benchmark data for several operational services such as ESA CCI Soil Moisture, the Copernicus Climate Change (C3S), the Copernicus Global Land Service (CGLS) and the online validation service Quality Assurance for Soil Moisture (QA4SM). In general, ISMN data is widely used in a variety of scientific fields (e.g. climate, water, agriculture, disasters, ecosystems, weather, biodiversity, etc.).</p><p>About 10’000 datasets are available through the web portal. However, the spatial coverage of in situ observations still needs to be improved. For example, in Africa and South America only sparse data are available. Innovative ideas, such as the inclusion of soil moisture data from low cost sensors (eventually) collected by citizen scientists, holds the potential of closing this gap, thus providing new information and knowledge.</p><p>In this session, we give an overview of the ISMN, its unique features and its benefits for validating satellite soil moisture products.</p>

Assessing the Representativeness and Sufficiency of Chemical Data from Water Samples Collected During an Oil Spill

2017 ◽  
Vol 2017 (1) ◽  
pp. 2581-2599
Author(s):  
Ann Michelle Morrison ◽  
Melanie Edwards ◽  
John Buonagurio ◽  
Linda Cook ◽  
Karen Murray ◽  
...  
Keyword(s):  
Water Chemistry ◽  
Water Column ◽  
Oil Spill ◽  
Sampling Design ◽  
Survey Design ◽  
Three Dimensional ◽  
Chemical Exposure ◽  
Sufficient Information ◽  
Sample Collection ◽  
Chemistry Data

ABSTRACT Traditionally, the representativeness and sufficiency of data in environmental monitoring efforts are judged against an external standard, such as a pre-determined statistically-based survey design intended to achieve specified data quality objectives. However, given the nature of oil spill responses, where the primary focus is usually on finding the oil and documenting exposure related to the release, samples collected from oil spill studies rarely follow a statistically-based, pre-determined sampling design. Using water chemistry data from the Deepwater Horizon oil spill, we have developed statistical, observational, and forensic approaches to evaluate the representativeness and sufficiency of field-collected chemistry data to characterize exposure in the water column. Three complementary approaches were selected for evaluating water chemistry data. The first “Zone” approach evaluates properties of the data within defined spatial-temporal exposure zones. The second “Probability” approach examines the data independent of predetermined zones using three dimensional (3D; i.e., latitude, longitude, depth) modeling methods (interpolation, contouring) to assess whether the field-collected water chemistry data alone provide sufficient information to model chemical exposure in the water column. The final “Design” approach compares the field-collected sample data to a theoretical sampling design that could have been developed at the beginning of the incident. Integral to all of these approaches is a pre-analysis screening that considers the original objective of each sample collection and the method of sample collection. Review of the chemical forensics of samples can provide further refinement. In this way, samples that were collected as part of a targeted effort based on visual or sensor observations can be considered in light of the context in which they were collected. The results of this analysis can be used to inform future oil spill sample collections to provide sufficient and representative samples that meet the immediate needs of the response as well as longer-term damage assessment determinations.

AUV Sensors for Real-Time Detection, Localization, Characterization, and Monitoring of Underwater Munitions

2009 ◽  
Vol 43 (4) ◽  
pp. 76-84 ◽  
Author(s):  
Richard Camilli ◽  
Brian S. Bingham ◽  
Michael V. Jakuba ◽  
Anthony N. Duryea ◽  
Rand LeBouvier ◽  
...  
Keyword(s):  
Real Time ◽  
Situation Awareness ◽  
Chemical Sensors ◽  
Autonomous Underwater Vehicles ◽  
Underwater Vehicles ◽  
Chemical Plume Tracing ◽  
Plume Tracing ◽  
Chemical Plume ◽  
New Research

AbstractThis technical paper describes existing capabilities and new research results for autonomous underwater vehicles (AUVs) for use in locating, characterizing, and monitoring underwater munitions. The authors introduce advances in sensor technologies and search methods pertinent to AUV-based underwater munition mitigation operations. Results are presented from a series of trials using in situ chemical sensors to detect both conventional and nonconventional underwater munitions in real time. These technologies are considered within the context of chemical plume tracing and biomimetic search algorithms. This paper concludes with a look toward future AUV sensor payloads with more extensive real-time situation awareness. Advancement of these technologies and methods will be critical for realizing the potential of AUV platforms to manage the risks posed by underwater munitions sites.

scholarly journals Estimation of Daily Potential Evapotranspiration in Real-Time from GK2A/AMI Data Using Artificial Neural Network for the Korean Peninsula

Hydrology ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 129
Author(s):  
Jae-Cheol Jang ◽  
Eun-Ha Sohn ◽  
Ki-Hong Park ◽  
Soobong Lee
Keyword(s):  
Neural Network ◽  
Artificial Neural Network ◽  
Real Time ◽  
Korean Peninsula ◽  
Potential Evapotranspiration ◽  
Weather Prediction ◽  
Spatiotemporal Variability ◽  
Artificial Neural ◽  
Using Data

Evapotranspiration (ET) is a fundamental factor in energy and hydrologic cycles. Although highly precise in-situ ET monitoring is possible, such data are not always available due to the high spatiotemporal variability in ET. This study estimates daily potential ET (PET) in real-time for the Korean Peninsula, via an artificial neural network (ANN), using data from the GEO-KOMPSAT 2A satellite, which is equipped with an Advanced Meteorological Imager (GK2A/AMI). We also used passive microwave data, numerical weather prediction (NWP) model data, and static data. The ANN-based PET model was trained using data for the period 25 July 2019 to 24 July 2020, and was tested by comparing with in-situ PET for the period 25 July 2020 to 31 July 2021. In terms of accuracy, the PET model performed well, with root-mean-square error (RMSE), bias, and Pearson’s correlation coefficient (R) of 0.649 mm day−1, −0.134 mm day−1, and 0.954, respectively. To examine the efficiency of the GK2A/AMI-derived PET data, we compared it with in-situ ET measured at flux towers and with MODIS PET data. The accuracy of the GK2A/AMI-derived PET, in comparison with the flux tower-measured ET, showed RMSE, bias, and Pearson’s R of 1.730 mm day−1, 1.212 mm day−1, and 0.809, respectively. In comparison with the in-situ PET, the ANN model produced more accurate estimates than the MODIS data, indicating that it is more locally optimized for the Korean Peninsula than MODIS. This study advances the field by applying an ANN approach using GK2A/AMI data and could play an important role in examining hydrologic energy for air-land interactions.

Understanding Interphase Boundary Dynamics by In Situ High-Resolution and Energy-Filtering Transmission Electron Microscopy and Real-Time Image Simulation

1998 ◽  
Vol 4 (3) ◽  
pp. 235-247 ◽  
Author(s):  
J.M. Howe ◽  
T.M. Murray ◽  
K.T. Moore ◽  
A.A. Csontos ◽  
M.M. Tsai ◽  
...  
Keyword(s):  
High Resolution ◽  
Real Time ◽  
Interphase Boundary ◽  
Three Dimensional ◽  
Atomic Level ◽  
Dimensional Structure ◽  
Energy Filtering ◽  
Transmission Electron ◽  
Boundary Dynamics

This study discusses the use of in situ high-resolution transmission electron microscropy (HRTEM) techniques to determine the structure, composition, and interphase boundary dynamics during phase transformations at the atomic level. Three main in situ HRTEM techniques are described: (1) in situ HRTEM dynamic studies that are performed on the same precipitate plates from different viewing directions to determine the three-dimensional structure of the interfaces; (2) in situ compositional mapping of precipitate interfaces obtained by energy-filtering TEM experiments at temperature in a HRTEM, and (3) real-time HRTEM image simulations that are being created for comparison with and interpretation of experimental in situ HRTEM dynamic observations. The results from these studies demonstrate that it is possible to understand the mechanisms and kinetics of interphase boundary motion at the atomic level.

scholarly journals 3D cardiac μtissues within a microfluidic device with real-time contractile stress readout

Lab on a Chip ◽  
2016 ◽  
Vol 16 (1) ◽  
pp. 153-162 ◽  
Author(s):  
Aereas Aung ◽  
Ivneet Singh Bhullar ◽  
Jomkuan Theprungsirikul ◽  
Shruti Krishna Davey ◽  
Han Liang Lim ◽  
...  
Keyword(s):  
Real Time ◽  
Microfluidic Device ◽  
Three Dimensional ◽  
Stress Measurements ◽  
Contractile Stress

We present the development of three-dimensional (3D) cardiac microtissues within a microfluidic device with the ability to quantify real-time contractile stress measurementsin situ.

Three Dimensional Path Planning of Autonomous Underwater Vehicles

2013 ◽  
Vol 328 ◽  
pp. 128-132
Author(s):  
Yan Peng ◽  
Wei Qing Wu ◽  
Mei Liu ◽  
Shao Rong Xie ◽  
Jun Luo
Keyword(s):  
Lyapunov Function ◽  
Path Planning ◽  
Real Time ◽  
Tracking Control ◽  
Autonomous Underwater Vehicle ◽  
Autonomous Underwater Vehicles ◽  
Three Dimensional ◽  
Underwater Vehicle ◽  
Underwater Vehicles ◽  
Control Lyapunov Function

The path planning relates to the safe movement and navigation of the Autonomous Underwater Vehicles (AUV). This paper discusses the way of real-time path planning for autonomous underwater vehicle based on tracking control lyapunov function. The simulation conducted on H300 illustrates the effectiveness of proposed method.

Mobile Voltammetric Laboratory for Ship-Board and Shore-Based Analyses of Dissolved Copper

2006 ◽  
Vol 3 (6) ◽  
pp. 450 ◽  
Author(s):  
Sarah Knight ◽  
Nicholas Morley ◽  
Dónal Leech ◽  
Rachel Cave
Keyword(s):  
Real Time ◽  
Surface Waters ◽  
Low Cost ◽  
Stripping Voltammetry ◽  
Mobile Laboratory ◽  
Sample Collection ◽  
The Real ◽  
Cathodic Stripping Voltammetry ◽  
Spatial Coverage ◽  
Cathodic Stripping

Environmental Context. Determining concentrations of dissolved copper in seawater is of interest, because copper (i) affects the health of aquatic biota, and (ii) has the potential to act as a water mass tracer, a marker which can be used to follow the movement of water in oceans. In situ analyses of copper and other trace metals in seawater have become increasingly popular, because they circumvent potential contamination problems associated with sample collection, storage, and transport to off-site analysis locations. This paper describes the assembly of a low-cost, mobile laboratory utilizing adsorptive cathodic stripping voltammetry (AdCSV) for the real-time determination of total dissolved copper in surface waters. Abstract. The main advantages of using a mobile laboratory for the real-time analyses of copper in surface waters over classical discrete sampling include a reduction in the risk of sample contamination and significant savings in both time and money to the analyst. This paper outlines the development of a portable voltammetric laboratory, capable of deployment from ships or road vehicles, and an experimental method for the real time analysis of total dissolved copper in surface waters. It has been tested in estuarine and coastal waters to the west of Ireland and has proved suitable for the analysis of both fresh and marine waters. The system includes a trace metal-free sampling fish (for shipboard sampling), in-line filtration and UV-digestion units, and a voltammetric analyzer and electrode controlled by a portable PC. Analysis of samples is completed using adsorptive cathodic stripping voltammetry (AdCSV). Using this portable AdCSV laboratory, the high sample throughput – approximately three per hour with standard additions completed on every sample – means that for ship-board surveys good spatial coverage is possible without the need for time-consuming station stops. For van-based tidal surveys, the portable AdCSV laboratory is both straightforward and low in cost to deploy.

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