scholarly journals Rapid Detection of Windthrows Using Sentinel-1 C-Band SAR Data

2019 ◽  
Vol 11 (2) ◽  
pp. 115 ◽  
Author(s):  
Marius Rüetschi ◽  
David Small ◽  
Lars Waser
Keyword(s):  
Rapid Detection ◽  
Temperate Forests ◽  
Weather Conditions ◽  
Independent Study ◽  
Storm Event ◽  
Storm Events ◽  
Before And After ◽  
Sar Data ◽  
Short Time ◽  
Flexible Application

Storm events are capable of causing windthrow to large forest areas. A rapid detection of the spatial distribution of the windthrown areas is crucial for forest managers to help them direct their limited resources. Since synthetic aperture radar (SAR) data is acquired largely independent of daylight or weather conditions, SAR sensors can produce temporally consistent and reliable data with a high revisit rate. In the present study, a straightforward approach was developed that uses Sentinel-1 (S-1) C-band VV and VH polarisation data for a rapid windthrow detection in mixed temperate forests for two study areas in Switzerland and northern Germany. First, several S-1 acquisitions of approximately 10 before and 30 days after the storm event were radiometrically terrain corrected. Second, based on these S-1 acquisitions, a SAR composite image of before and after the storm was generated. Subsequently, after analysing the differences in backscatter between before and after the storm within windthrown and intact forest areas, a change detection method was developed to suggest potential locations of windthrown areas of a minimum extent of 0.5 ha—as is required by the forest management. The detection is based on two user-defined parameters. While the results from the independent study area in Germany indicated that the method is very promising for detecting areal windthrow with a producer’s accuracy of 0.88, its performance was less satisfactory at detecting scattered windthrown trees. Moreover, the rate of false positives was low, with a user’s accuracy of 0.85 for (combined) areal and scattered windthrown areas. These results underscore that C-band backscatter data have great potential to rapidly detect the locations of windthrow in mixed temperate forests within a short time (approx. two weeks) after a storm event. Furthermore, the two adjustable parameters allow a flexible application of the method tailored to the user’s needs.

The dynamics of faecal indicator organisms in a temperate river during storm conditions

2012 ◽  
Vol 3 (2) ◽  
pp. 139-150 ◽  
Author(s):  
Daniel Ekane Nnane ◽  
James Ebdon ◽  
Huw Taylor
Keyword(s):  
Weather Conditions ◽  
Water Quality Monitoring ◽  
Source Tracking ◽  
P Value ◽  
Storm Event ◽  
Storm Events ◽  
Indicator Organisms ◽  
Specific Strain ◽  
Summer Storm ◽  
Temperate River

Greater incidence of storm events, which can lead to greater contamination of surface waters by human and animal faeces, are a predicted feature of climate change in parts of Europe and elsewhere. The aim of this study was to combine the use of a novel quantitative microbial source tracking (QMST) method with established water quality monitoring procedures during an intense summer storm event in a rural UK river catchment, to establish dominant sources of faecal pollution. One-litre grab samples of river water were collected every 12 h for a period of seven days from three sampling sites on the Bevern Stream (a tributary of the Sussex Ouse). All samples were tested for a range of chemophysical and bacteriological parameters, and also for phage-lysis of a human specific strain of Bacteroides spp. GB-124. Presumptive levels of Escherichia coli and intestinal enterococci were statistically significantly (p-value < 0.05) higher during the storm event, compared with dry weather conditions. Low recorded levels of phages of Bacteroides GB-124 during the storm event, compared with dry weather conditions, support the hypothesis that the predominant sources of faecal material in the river during the storm event were non-human. Using traditional faecal indicator bacteria and a QMST marker during storm events may improve human health protection protocols.

Rapid mapping of landslides by Deep-Learning of combined optical and SAR data

2021 ◽  
Author(s):  
Lorenzo Nava ◽  
Filippo Catani ◽  
Oriol Monserrat
Keyword(s):  
Deep Learning ◽  
Cloud Cover ◽  
Optical Data ◽  
Rapid Mapping ◽  
Optical Images ◽  
Short Time Span ◽  
Before And After ◽  
Comparable Accuracy ◽  
Sar Data ◽  
Short Time

<div> <p><span>In the world, various natural calamities, like earthquakes and massive rainfalls sometimes combined with windstorms, can trigger multiple landslide events that can occur in groups of hundreds to thousands in a region, over a short time span. Therefore, there is a growing need to be able to intervene quickly to accurately map the impacted areas. To this end, VHR optical images ensure best performances in terms of spatial accuracy but, for rapid mapping, they present limitations due to the possible presence of cloud cover as, often, the first cloudless image is available with an unacceptable time delay, see, e.g., the cases of strong earthquakes of Chile 2017, Nepal 2015 and Ecuador 2016. A possible solution may stand in the combined exploitation of optical and SAR data. In this study, deep-learning convolution neural networks (CNNs) techniques have been used to compare and combine the mapping and classification performances of optical images (from Sentinel-2) and SAR images (from Sentinel-1). The training and test zones used to independently evaluate the performance of CNNs on different datasets are located in the eastern Iburi subprefecture in Hokkaido, where, at 03.08 local time (JST) on September 6, 2018, a Mw 6.6 earthquake triggered about 7837 coseismic landslides. We analyzed the conditions before and after the earthquake exploiting SAR and optical data by means of a series of CNNs implemented in Python that point out the locations where the <em>Landslide</em> class is predicted as more likely. As expected, the CNN run on optical images proved itself excellent for the landslide detection task, achieving an overall accuracy of 98.48% while a CNN based on the combination of ground range detected (GRD) data (SAR) achieved an overall accuracy of 95.54%. Despite this, the integrated use of SAR data allows for a rapid mapping even during storms and under cloud cover and seems to provide a comparable accuracy than optical change detection. We believe that, in the near future, such classification accuracy might even increase with the availability of new, VHR SAR products, such as the 50 cm x 50 cm resolution imagery from the Capella-2 satellite.</span></p> </div>

Evaluation of Metal Contents in Correlation with Phytosanitary Treatments at Vineyard

2017 ◽  
Vol 68 (6) ◽  
pp. 1289-1293
Author(s):  
Oana Mihai ◽  
Octav Pantea ◽  
Daniela Roxana Popovici ◽  
Catalina Gabriela Gheorghe
Keyword(s):  
Soil Samples ◽  
Flame Atomic Absorption ◽  
Mobile Forms ◽  
Before And After ◽  
Phytosanitary Treatment ◽  
Zinc Concentrations ◽  
Zinc Levels ◽  
Ph Range ◽  
In The Beginning ◽  
Short Time

The present work aims with the evaluation of copper, manganese and zinc concentrations (mobile forms) from vineyard soil before and after phytosanitary treatment with Curzate Manox and Dithane M-45 compounds, during and after remanence period. Different vineyard soils types were collected at 0-20 cm and 20-40 cm depths. Flame Atomic Absorption Spectroscopy (FAAS) method was used for measurements of the micronutrients. The soil samples were analyzed after 5 and 21 days after treatment application. Since copper is mainly accumulates in the upper layer following fungicidal sprays application, high levels of copper concentrations are obtained. The soil samples exhibits different behavior in terms of manganese and zinc contents. Manganese and zinc levels are classified as medium in the beginning of the experiment (Mn-M0 and Zn-M0), whereas these levels increased in the soil samples (at moments M1- 5 days and M2- 21 days after treatment). This behavior can be due to the Mancozeb decomposition, knowing that Mancozeb decomposes in the pH range 5-9 and it remains short time into the soil.

scholarly journals High Oxygen Packaging of Atlantic Cod Fillets Inhibits Known Spoilage Organisms, but Sensory Quality Is Not Improved Due to the Growth of Carnobacterium/Carnobacteriaceae

Foods ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1754
Author(s):  
Anlaug Ådland Hansen ◽  
Solveig Langsrud ◽  
Ingunn Berget ◽  
Mari Øvrum Gaarder ◽  
Birgitte Moen
Keyword(s):  
Shelf Life ◽  
Sensory Quality ◽  
Atlantic Cod ◽  
Bacterial Load ◽  
Modified Atmosphere Packaging ◽  
Volatile Components ◽  
Spoilage Bacteria ◽  
Before And After ◽  
Thawing Process ◽  
Short Time

Improved quality control and prolonged shelf life are important actions in preventing food waste. To get an overview of the bacterial diversity of fillets from live stored mature Atlantic cod, bacterial isolates were identified before and after storage (air and vacuum) and freezing/thawing. Based on the load of dominating bacteria, the effect of different packaging methods and a short freezing/thawing process on prolonged shelf-life was evaluated (total viable counts, bacteriota, sensory attributes, and volatile components). Hand filleted (strict hygiene) cod fillets had a low initial bacterial load dominated by the spoilage organism Photobacterium, whereas industrially produced fillets had higher bacterial loads and diversity (Pseudomonas, Arthrobacter, Psychrobacter, Shewanella). The identified bacteria after storage in vacuum or air were similar to the initially identified bacteria. Bacteriota analysis showed that a short time freezing/thawing process reduced Photobacterium while modified atmosphere packaging (MAP; 60%CO2/40%O2 or 60%CO2/40%N2) inhibited the growth of important spoilage bacteria (Photobacterium, Shewanella, Pseudomonas) and allowed the growth of Carnobacterium/Carnobacteriaceae and Acinetobacter. Despite being dominated by Photobacterium, fresh fillets stored in MAP 60%CO2/40%N2 demonstrated better sensory quality after 13 days of storage than fillets stored in MAP 60%CO2/40%O2 (dominated by Carnobacterium/Carnobacteriaceae). Carnobacterium spp. or other members of Carnobacteriaceae may therefore be potential spoilage organisms in cod when other spoilage bacteria are reduced or inhibited.

scholarly journals The effects of the big storm events in the first half of 2015 on the radiation belts observed by EPT/PROBA-V

2016 ◽  
Vol 34 (1) ◽  
pp. 75-84 ◽  
Author(s):  
V. Pierrard ◽  
G. Lopez Rosson
Keyword(s):  
Charged Particle ◽  
High Resolution ◽  
Geomagnetic Storm ◽  
Energetic Particle ◽  
High Energy ◽  
Radiation Belts ◽  
Radiation Environment ◽  
Storm Event ◽  
Storm Events ◽  
Particle Radiation

Abstract. With the energetic particle telescope (EPT) performing with direct electron and proton discrimination on board the ESA satellite PROBA-V, we analyze the high-resolution measurements of the charged particle radiation environment at an altitude of 820 km for the year 2015. On 17 March 2015, a big geomagnetic storm event injected unusual fluxes up to low radial distances in the radiation belts. EPT electron measurements show a deep dropout at L > 4 starting during the main phase of the storm, associated to the penetration of high energy fluxes at L < 2 completely filling the slot region. After 10 days, the formation of a new slot around L = 2.8 for electrons of 500–600 keV separates the outer belt from the belt extending at other longitudes than the South Atlantic Anomaly. Two other major events appeared in January and June 2015, again with injections of electrons in the inner belt, contrary to what was observed in 2013 and 2014. These observations open many perspectives to better understand the source and loss mechanisms, and particularly concerning the formation of three belts.

scholarly journals Boosting English Competency and Learning Motivation Through the Integrated Approach For Non-English Departments Students

ELT-Lectura ◽  
2021 ◽  
Vol 8 (1) ◽  
pp. 1-14
Author(s):  
Samsul Amri ◽  
Syafrizal
Keyword(s):  
Time Allocation ◽  
Integrated Approach ◽  
Learning Motivation ◽  
Affecting Factors ◽  
English Departments ◽  
Data Collection Process ◽  
Improvement Process ◽  
Before And After ◽  
Internal And External Factors ◽  
Short Time

At the tertiary level, English as a General Subject supports the learning process's main course. The observations show they are not yet proficient enough to use it. It causes indisposed motivation, dearth vocabulary, low learning interest, short time allocation, and others. Therefore, the researchers provide a solution by applying the Integrated Approach. The research objectives are to determine whether the Integrated Approach can improve English competency and learning motivation, how the learners’ improvement process, and what factors influence these improvements. It is action research, which was Accounting majoring students as subjects - Islamic University of Indragiri. The data collection process used tests and questionnaires. Furthermore, the results showed an increase in their competence and motivation to learn English before and after the Integrated Approach. The improvement process covers several activities; socializing, analyzing, monitoring, guiding, and practicing. Meanwhile, the development affecting factors are internal and external factors such as learning motivation, teaching methods, and the instructors’ roles. In conclusion, the Integrated Approach application positively contributes to the learners’ learning outcomes and motivation.

Structural, Textural and Thermal Characterization of Nano-Mg/Al Hydrotalcite before and after Cr (VI) Removal

2013 ◽  
Vol 755 ◽  
pp. 53-60
Author(s):  
Esthela Ramos Ramírez ◽  
Norma Leticia Gutiérrez Ortega ◽  
Cesar Augusto Contreras Soto ◽  
Gustavo Rangel Porras
Keyword(s):  
Crystalline Structure ◽  
Sol Gel ◽  
Textural Properties ◽  
Kinetic Studies ◽  
Thermal Characterization ◽  
Gel Method ◽  
Sol Gel Method ◽  
Before And After ◽  
Short Time

In this work there was studied the structural, textural and effect that has treat thermal on the removal of Cr (VI) of nanoMg/Al hydrotalcite (NHT) synthesized by the sol-gel method with a ratio of Mg/Al=3. These present the characterization of the nanoMg/Al hydrotalcite before and after Cr (VI) removal, as well as the kinetic studies and of balance. In agreement with the results, when the NHT are thermal treated to 350 °C the hydrotalcite crystalline structure remains but the textural properties are improved and structural. The NHT synthesized by the sol-gel method present a good capacity of removal with values of 91 mg of Cr (VI) removed / g of NHT. The above mentioned capacity of removal gets improved after thermal treating the material, reaching values of removal of 124 mg of Cr (VI) removed / g of NHT. The NHT with the Cr (VI) absorbed show decrease of the crystalline structure, as well as a saturation of the pores that annuls the porosity due to the fact that the Cr (VI) lodges both at the pores and at the intersheets. The time that him takes the HLM to remove the Cr (VI) of the watery solution is alone of 2 minutes, with which it is possible to conclude that the NHT have an excellent aptitude to remove Cr (VI) of watery solutions in an interval of very short time.

scholarly journals Rapid tranquillisation: practice in Zambia, before and after training

2013 ◽  
Vol 10 (4) ◽  
pp. 95-97
Author(s):  
Mahesh Jayaram ◽  
Ranga Rattehalli ◽  
Lindsay Moran ◽  
John Mwanza ◽  
Paul Banda ◽  
...  
Keyword(s):  
Evidence Base ◽  
Sub Saharan Africa ◽  
Collaborative Partnerships ◽  
Inappropriate Use ◽  
Short Time Span ◽  
Safety Awareness ◽  
Before And After ◽  
Sub Saharan ◽  
Therapeutic Doses ◽  
Short Time

The evidence base for rapid tranquillisation is small in higher-income countries but is even smaller in sub-Saharan Africa. We initiated the first ever survey on the use of rapid tranquillisation in Zambia in 2009; a further survey was then done in 2010, after a programme of teaching and training. It demonstrated an overall improvement in clinical practice, safety, awareness and use of medications within therapeutic doses. It also led to a reduction in inappropriate use of medications. These improvements in practice occurred within a short time span and with minimal effort. Further international collaborative partnerships are required to build stronger mental health infrastructure in Zambia.

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