MicroPulse DIAL (MPD) – a Diode-Laser-Based Lidar Architecture for Quantitative Atmospheric Profiling

Abstract. Continuous water vapor and temperature profiles are critically needed for improved understanding of the lower atmosphere and potential advances in weather forecasting skill. Ground-based, national-scale profiling networks are part of a suite of instruments to provide such observations; however, the technological method must be cost-effective and quantitative. We have been developing an active remote sensing technology based on a diode-laser-based lidar technology to address this observational need. Narrowband, high-spectral-fidelity diode lasers enable accurate and calibration-free measurements requiring a minimal set of assumptions based on direct absorption (Beer–Lambert law) and a ratio of two signals. These well-proven quantitative methods are known as differential absorption lidar (DIAL) and high-spectral-resolution lidar (HSRL). This diode-laser-based architecture, characterized by less powerful laser transmitters than those historically used for atmospheric studies, can be made eye-safe and robust. Nevertheless, it also requires solar background suppression techniques such as narrow-field-of-view receivers with an ultra-narrow bandpass to observe individual photons backscattered from the atmosphere. We discuss this diode-laser-based lidar architecture's latest generation and analyze how it addresses a national-scale profiling network's need to provide continuous thermodynamic observations. The work presented focuses on general architecture changes that pertain to both the water vapor and the temperature profiling capabilities of the MicroPulse DIAL (MPD). However, the specific subcomponent testing and instrument validation presented are for the water vapor measurements only. A fiber-coupled seed laser transmitter optimization is performed and shown to meet all of the requirements for the DIAL technique. Further improvements – such as a fiber-coupled near-range receiver, the ability to perform quality control via automatic receiver scanning, advanced multi-channel scalar capabilities, and advanced processing techniques – are discussed. These new developments increase narrowband DIAL technology readiness and are shown to allow higher-quality water vapor measurements closer to the surface via preliminary intercomparisons within the MPD network itself and with radiosondes.

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MicroPulse DIAL (MPD) ground-based network for Thermodynamic Profiling in the Lower Troposphere

10.5194/egusphere-egu2020-10310 ◽

2020 ◽

Author(s):

Scott Spuler ◽

Robert Stillwell ◽

Matt Hayman ◽

Tammy Weckwerth ◽

Kevin Repasky

Keyword(s):

Water Vapor ◽

Weather Forecasting ◽

Low Cost ◽

Lower Troposphere ◽

Atmospheric Temperature ◽

Lower Atmosphere ◽

High Spectral Resolution ◽

Montana State University ◽

Aerosol Scattering ◽

Thermodynamic Variables

The National Center for Atmospheric Research and Montana State University have developed a 5-unit ground-based test network of MicroPulse Differential Absorption Lidar (MPD) instruments to continuously measure high-vertical-resolution water vapor profiles in the lower atmosphere. These diode-laser-based instruments are accurate, low-cost, operate unattended, do not require external calibration, and eye-safe &#8211; all key features to enable larger 'national-scale' networks needed to characterize atmospheric moisture variability, which influences important processes related to weather and climate.&#160; Enhancements to the water vapor MPD architecture have been recently developed that enable quantitative aerosol measurements and atmospheric temperature profiling by simultaneously measuring O2 absorption and aerosol backscatter ratio. This combination of measurements allows for the first DIAL measurements of atmospheric temperature with useful accuracy. The MPD has been demonstrated to provide continuous, range-resolved measurements of atmospheric thermodynamic variables, water vapor and temperature, and quantitative measurements of aerosol scattering from a high spectral resolution (HSRL) channel.&#160; Thus, a network of these instruments shows promise to provide atmospheric profiling capabilities needed by both the climate and weather forecasting research communities.

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Biosensors and nanomaterials and their application for mycotoxin determination

World Mycotoxin Journal ◽

10.3920/wmj2011.1318 ◽

2011 ◽

Vol 4 (4) ◽

pp. 361-374 ◽

Cited By ~ 61

Author(s):

I. Tothill

Keyword(s):

Food Quality ◽

Quantitative Methods ◽

Scientific Literature ◽

Cost Effective ◽

Screening Tools ◽

Field Analysis ◽

Quality And Safety ◽

Site Testing ◽

Food Quality And Safety ◽

Mycotoxin Analysis

Mycotoxin analysis and detection in food and drinks is vital for ensuring food quality and safety, eliminating and controlling the risk of consuming contaminated foods, and complying with the legislative limits set by food authorities worldwide. Most analysis of these toxins is still conducted using conventional methods; however, biosensor methods are currently being developed as screening tools for use in field analysis. Biosensors have demonstrated their ability to provide rapid, sensitive, robust and cost-effective quantitative methods for on-site testing. The development of biosensor devices for different mycotoxins has attracted much research interest in recent years with a range of devices being designed and reported in the scientific literature. However, with the advent of nanotechnology and its impact on the evolution of ultrasensitive devices, mycotoxin analysis is also benefiting from the advances taking place in applying nanomaterials in sensors development. This paper reviews the developments in the area of biosensors and their applications for mycotoxin analysis, as well as the development of micro/nanoarray transducers and nanoparticles and their use in the development of new rapid devices.

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Leveraging machine learning to produce a cost-effective national building height map of Ireland

10.5194/ems2021-48 ◽

2021 ◽

Author(s):

Eoghan Keany ◽

Geoffrey Bessardon ◽

Emily Gleeson

Keyword(s):

Machine Learning ◽

Remote Sensing ◽

High Resolution ◽

Land Cover ◽

Urban Areas ◽

Cost Effective ◽

Land Cover Classification ◽

National Scale ◽

Building Height ◽

Height Data

To represent surface thermal, turbulent and humidity exchanges, Numerical Weather Prediction (NWP) systems require a land-cover classification map to calculate sur-face parameters used in surface flux estimation. The latest land-cover classification map used in the HARMONIE-AROME configuration of the shared ALADIN-HIRLAMNWP system for operational weather forecasting is ECOCLIMAP-SG (ECO-SG). The first evaluation of ECO-SG over Ireland suggested that sparse urban areas are underestimated and instead appear as vegetation areas (1). While the work of (2) on land-cover classification helps to correct the horizontal extent of urban areas, the method does not provide information on the vertical characteristics of urban areas. ECO-SG urban classification implicitly includes building heights (3), and any improvement to ECO-SG urban area extent requires a complementary building height dataset.Openly accessible building height data at a national scale does not exist for the island of Ireland. This work seeks to address this gap in availability by extrapolating the preexisting localised building height data across the entire island. The study utilises information from both the temporal and spatial dimensions by creating band-wise temporal aggregation statistics from morphological operations, for both the Sentinel-1A/B and Sentinel-2A/B constellations (4). The extrapolation uses building height information from the Copernicus Urban Atlas, which contains regional coverage for Dublin at 10 m x10 m resolution (5). Various regression models were then trained on these aggregated statistics to make pixel-wise building height estimates. These model estimates were then evaluated with an adjusted RMSE metric, with the most accurate model chosen to map the entire country. This method relies solely on freely available satellite imagery and open-source software, providing a cost-effective mapping service at a national scale that can be updated more frequently, unlike expensive once-off private mapping services. Furthermore, this process could be applied by these services to reduce costs by taking a small representative sample and extrapolating the rest of the area. This method can be applied beyond national borders providing a uniform map that does not depends on the different private service practices facilitating the updates of global or continental land-cover information used in NWP.&#160;(1) G. Bessardon and E. Gleeson, &#8220;Using the best available physiography to improve weather forecasts for Ireland,&#8221; in Challenges in High-Resolution Short Range NWP at European level including forecaster-developer cooperation, European Meteorological Society, 2019.(2) E. Walsh, et al., &#8220;Using machine learning to produce a very high-resolution land-cover map for Ireland, &#8221; Advances in Science and Research,&#160; (accepted for publication).(3) CNRM, "Wiki - ECOCLIMAP-SG" https://opensource.umr-cnrm.fr/projects/ecoclimap-sg/wiki(4) D. Frantz, et al., &#8220;National-scale mapping of building height using sentinel-1 and sentinel-2 time series,&#8221; Remote Sensing of Environment, vol. 252, 2021.(5) M. Fitrzyk, et al., &#8220;Esa Copernicus sentinel-1 exploitation activities,&#8221; in IGARSS 2019-2019 IEEE International Geoscience and Remote Sensing Symposium, IEEE, 2019.

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Financial Inclusion in Developing Countries: Applying Financial Technology as a Panacea

South Asian Journal of Social Studies and Economics ◽

10.9734/sajsse/2021/v9i230237 ◽

2021 ◽

pp. 42-60

Author(s):

Araniyar Isukul ◽

Ben Tantua

Keyword(s):

Developing Countries ◽

Financial Development ◽

Low Income ◽

Quantitative Methods ◽

Cost Effective ◽

Financial Inclusion ◽

Viable Option ◽

Policy Objective ◽

Banking Business ◽

Financial Technology

Traditional banking methods of addressing the problem of financial inclusion in developing countries is not working efficiently. As it is becoming obvious, opening operational and functional banking business offices in many developing countries is not a financially viable option. Banking offices need enormous amounts of resources, equipment and personnel to run efficiently. In most developing countries were low income is the norm rather than the exception, it is not possible to sustain a policy objective that employs the use of banking business offices to address the problem of financial inclusion. Such initiative could start out well, however the possibility of sustainability is called into question. Thus, whatever meaningful gains have been garnered from such policy will be reversed or lost overtime. This research employs the use of quantitative methods and it sets out to test whether the usage of financial technology has had any meaningful impact in improving financial inclusion in the developing countries selected in the study. The findings of the research reveal that financial technology offers the instrument, tools and mechanism for drive financial inclusion in ways traditional methods of banking cannot. Financial technology offers, cost effective and cheaper means of driving financial development. This research suggests that financial technology should be used as a means of driving financial development in developing countries as it offers a more sustainable and cost-effective solution to the problem of financial inclusion. Developing countries, should embrace, adopt and adapt financial technologies to address their financial development issues.

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High-Resolution Melting-Based Quantitative Analysis of RASSF1 Methylation in Breast Cancer

Medicina ◽

10.3390/medicina49020014 ◽

2013 ◽

Vol 49 (2) ◽

pp. 14 ◽

Cited By ~ 1

Author(s):

Kristina Stuopelytė ◽

Kristina Daniūnaitė ◽

Aida Laurinavičienė ◽

Valerijus Ostapenko ◽

Sonata Jarmalaitė

Keyword(s):

Breast Cancer ◽

Polymerase Chain Reaction ◽

High Resolution ◽

Quantitative Methods ◽

High Resolution Melting ◽

Cost Effective ◽

Chain Reaction ◽

Specific Polymerase Chain Reaction ◽

Polymerase Chain ◽

Breast Tissues

Background and Objective. Breast cancer is the leading cause of death from cancer among women worldwide. The aberrant promoter methylation of tumor suppressor genes is a typical epigenetic alteration for breast cancer and can be detected in early carcinogenesis. High-throughput and cost-effective methods are needed for the early and sensitive detection of epigenetic changes in clinical material. The main purpose of our study was to optimize a high-resolution melting (HRM) assay for the reliable and quantitative assessment of RASSF1 gene methylation, which is considered one of the earliest epigenetic alterations in breast cancer. Material and Methods. A total of 76 breast carcinomas and 10 noncancerous breast tissues were studied by means of HRM and compared with the results obtained by means of quantitative methylation-specific polymerase chain reaction (QMSP) and methylation-specific polymerase chain reaction (MSP). Results. Both quantitative methods, HRM and QMSP, showed a similar specificity and sensitivity for the detection of RASSF1 methylation in breast cancer (about 80% and 70%, respectively). In breast cancer, the mean methylation intensity of RASSF1 was 42.5% and 48.6% according to HRM and QMSP, respectively. Both methods detected low levels of methylation (less than 5%) in noncancerous breast tissues. In comparison with quantitative methods, MSP showed a lower sensitivity (70%), but a higher specificity (80%) for the detection of RASSF1 methylation in breast cancer. Conclusions. HRM is as a simple, cost-effective method for the reliable high-throughput quantification of DNA methylation in clinical material.

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Theory and method in the study of poverty in east Africa

Focaal ◽

10.3167/092012905780909225 ◽

2005 ◽

Vol 2005 (45) ◽

pp. 56-68 ◽

Cited By ~ 2

Author(s):

John R. Campbell

Keyword(s):

Poverty Reduction ◽

Quantitative Methods ◽

Rural Poverty ◽

Small Scale ◽

National Scale ◽

Policy Makers ◽

Qualitative And Quantitative Methods ◽

Methodological Choices ◽

Reduction Strategies ◽

Context Specific

This article explores the relation between theory and method in three methodologically innovative studies of rural poverty. The issue is pertinent because the nature of research on poverty has shifted from small-scale qualitative studies to large surveys, and to national-scale studies that combine qualitative and quantitative methods in an effort to inform policy makers on appropriate poverty reduction strategies. The interest in combined methods holds considerable promise for poverty research because it links a search for 'objective' economic concerns to the analysis of 'subjective' and context-specific issues. It is instructive to examine recent studies of poverty that have pursued different theoretical and methodological choices with a view to understand how 'theory' influenced methodological choices, and whether and how such choices influenced their understanding of poverty.

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Evolution of a pyrocumulonimbus event associated with an extreme wildfire in Tasmania, Australia

Natural Hazards and Earth System Science ◽

10.5194/nhess-20-1497-2020 ◽

2020 ◽

Vol 20 (5) ◽

pp. 1497-1511 ◽

Cited By ~ 2

Author(s):

Mercy N. Ndalila ◽

Grant J. Williamson ◽

Paul Fox-Hughes ◽

Jason Sharples ◽

David M. J. S. Bowman

Keyword(s):

Weather Forecasting ◽

Fire Severity ◽

Atmospheric Stability ◽

Lower Atmosphere ◽

Fire Weather ◽

Natural Ecosystems ◽

Near Surface ◽

South Eastern ◽

Crown Defoliation ◽

Extreme Fire

Abstract. Extreme fires have substantial adverse effects on society and natural ecosystems. Such events can be associated with the intense coupling of fire behaviour with the atmosphere, resulting in extreme fire characteristics such as pyrocumulonimbus cloud (pyroCb) development. Concern that anthropogenic climate change is increasing the occurrence of pyroCbs globally is driving more focused research into these meteorological phenomena. Using 6 min scans from a nearby weather radar, we describe the development of a pyroCb during the afternoon of 4 January 2013 above the Forcett–Dunalley fire in south-eastern Tasmania. We relate storm development to (1) near-surface weather using the McArthur forest fire danger index (FFDI) and the C-Haines index, the latter of which is a measure of the vertical atmospheric stability and dryness, both derived from gridded weather reanalysis for Tasmania (BARRA-TA); and (2) a chronosequence of fire severity derived from remote sensing. We show that the pyroCb rapidly developed over a 24 min period on the afternoon of 4 January, with the cloud top reaching a height of 15 km. The pyroCb was associated with a highly unstable lower atmosphere (C-Haines value of 10–11) and severe–marginally extreme (FFDI 60–75) near-surface fire weather, and it formed over an area of forest that was severely burned (total crown defoliation). We use spatial patterns of elevated fire weather in Tasmania and fire weather during major runs of large wildfires in Tasmania for the period from 2007 to 2016 to geographically and historically contextualise this pyroCb event. Although the Forcett–Dunalley fire is the only known record of a pyroCb in Tasmania, our results show that eastern and south-eastern Tasmania are prone to the conjunction of high FFDI and C-Haines values that have been associated with pyroCb development. Our findings have implications for fire weather forecasting and wildfire management, and they highlight the vulnerability of south-east Tasmania to extreme fire events.

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Evaluating Cost-Effective Methods for Rapid and Repeatable National Scale Detection and Mapping of Invasive Species Spread

Scientific Reports ◽

10.1038/s41598-019-43729-y ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Ruth A. Aschim ◽

Ryan K. Brook

Keyword(s):

Invasive Species ◽

Cost Effective ◽

National Scale ◽

Scale Detection

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Research and Development of Universal Equipment for Geological Hazard Monitoring and Early Warning

10.5194/egusphere-egu2020-8494 ◽

2020 ◽

Author(s):

Juan Ma ◽

Mingzhi Zhang ◽

Gan Qi ◽

Gloria Xing ◽

Zack Huang

Keyword(s):

Early Warning ◽

Field Tests ◽

Cost Effective ◽

Impact Factors ◽

Geological Hazard ◽

Sensing Technology ◽

Disaster Monitoring ◽

Adaptation Scenarios ◽

Monitoring And Early Warning

Hilly and mountainous areas account for 65% of the total land area in China. There were 286,708 potential geological hazard sites registered at the end of 2018, among which 276,600 were small-and medium-sized. Small and medium geological hazards are a priority in geological disaster prevention. However, due to their large number and the high prices of professional monitoring equipment, it is difficult to find a cost-effective and accurate monitoring technology, method, or means for their long-term disaster monitoring. To this end, this paper aims to explore a reliable, cost-effective, precise, easily installable, low-power solution for small and medium geological hazard monitoring and early warning, centring on characteristic quantities such as deformation before collapse, landslides, and other disasters, and some key impact factors such as rainfall, moisture content, stress, and displacement velocity. Using universal &#160;equipment&#160;based on microelectromechanical sensing technology and narrowband IoT technology, laboratory simulations and field tests were performed to research the equipment in terms of adaptation scenarios, effective monitoring ranges, installation methods and locations, and normalization of data reporting content, thus setting up a scientific method for small and medium geological hazard monitoring and early warning.

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