Challenging Weather Conditions Research Articles

Single Image Rain Removal via Cascading Attention Aggregation Network on Challenging Weather Conditions

Single Image Rain Removal via Cascading Attention Aggregation Network on Challenging Weather Conditions

Modelling and simulation of a wind energy system

Nowadays, wind energy systems are the most efficient systems of all renewable energy production systems. Therefore, all sizes and types of this kind of systems are available, but there are few portable systems which can be temporarily mounted in certain isolated areas. We propose in this case study another solution as an alternative: an adaptable mechatronic system which can withstand even in very difficult and challenging weather conditions due to their active surfaces that have reconfigurable automatic structure.

Variety, time of harvest and conditions during growing season have impact on red clover isoflavone content

Red clover (Trifolium pratense L.) is the predominant legume used in northern European agriculture. Official red clover variety trials are conducted by Natural Resources Institute Finland (Luke) to determine the value of field crop varieties. The trials used for the current analysis were conducted in Luke units in southern Finland (Mikkeli) and northern Finland (Ruukki) in two consecutive years. Plant samples for isoflavone analyses were collected from four varieties grown as four replicates and harvested twice during both growing seasons. The four main isoflavones biochanin A, genistein, daidzein and formononetin were analysed using high performance liquid chromatography. Total phytoestrogen content in the varieties varied in the range of 11.2−14.8 mg g-1 dry matter (DM). The variety and the time of harvest had most effect on the isoflavone, especially formononetin, contents of red clover. A more northern growing area and challenging weather conditions were associated with increased isoflavone concentrations.

Deterioration of cracks in onshore wind turbine foundations

Cracks can occur in reinforced-concrete onshore wind turbine foundations due to factors such as the use of substandard concrete mix, mistakes in foundation design or multi-stage concrete pouring under challenging weather conditions. Cracks are routinely identified via above ground inspections and follow-on examination of excavated underground surfaces and are repaired, for example with resin injection and grouting. Their impact on the structure or the efficacy of the repair are often unknown as crack degradation during normal operating conditions is unexplored. In this work, sub-surface cracks in an onshore wind turbine foundation have been instrumented with fibre-optic based strain sensors in an attempt to determine severity and magnitude of deterioration over time. Here we determine cracks monitored show a small magnitude of deterioration over the initial 9-month period after sensor installation, suggesting that repair is not required. We propose a novel methodology for the classification of the types of deterioration evident in cracks as “reactive”, “permanent” and “behavioural”, and demonstrate methods to extract these types of deterioration. Such methods will continually be developed over time as further knowledge of crack behaviour is gained to determine appropriate limits and identify the optimal time to repair.

A fine tuned tracking of vehicles under different video degradations

Estimating the tracking efficacy of vehicles in traffic videos is one of the most desirable analysis specially in the presence of a challenging weather conditions. In this paper, a fine-tuning Kalman filter based tracking system has been proposed so that it will work robustly on the traffic videos. Such tracking efficacy has been tested and tuned by integrating a system that calculates the distance between adjacent vehicles as a case study. The integrated system could provide some sort of traffic warning system according to the allowable traffic safety standards. Analysis has been utilized in two phases; phase (1): by changing the performance indices of Kalman filter parameters (initial estimation error, motion noise, and measurement noise). We have measured both average number of assigned tracks and processing time of interest in order to acquire best tuning decision. From observations, changing values of initial estimation error has no effect on the performance of the tracking efficacy however increasing both motion noise and measurement noise has an adverse impact on the tracking performance. Phase (2) by applying the integrated system on a degraded version of a captured urban traffic video to measure performance of the tracking procedure according to the existence of salt and pepper, Gaussian, and Speckle video degradations. Such video disturbances could perform an evaluation for some sort of challenging weather conditions (e.g., rain, fog, and reduced light conditions). It is obviously that average number of assigned tracks has been degraded in the presence of video disturbance with respect to percentage of occurrence and the appropriate statistical features (mean, and variance) of such degradation. Twelve different types of filtering mask have been applied in order to measure average number of assigned tracks (correct predictions) after the cleaning process. We have measured the deviation between both the no noise and the with noise traffic video to study effect of each filter mask within each noise type of video disturbance. Such deviation measurements introduce a decision making criteria for best tuning that increases the efficacy of the vehicular tracking.

Experiencing and Responding to Everyday Weather in Darwin, Australia: The Important Role of Tolerance

Abstract Climates are changing, yet the everyday implications for societies and cultures are unclear. Until recently, weather and climate (change) have been largely represented quantitatively and discussed at broad spatial and social scales. Qualitative weather research is helping to reconnect weather with its diverse local meanings and to explain how climate change may alter future representational and behavioral understands of weather (herein called “weather-relations”) in the hope of furthering climate change action. Responding to the need for greater research into weather-relations, particularly in industrialized urban areas, this paper examines the role of weather in everyday life in tropical Darwin, Australia. It identifies a willingness among participants to stay “weather-connected” despite challenging weather conditions and access to air conditioning. This willingness is driven by desires to remain acclimatized in order to enhance positive weather sensations, retain outdoor lifestyles, and reduce financial and environmental costs associated with resource-intensive technologies. In delving into weather adjustment strategies that facilitate weather-connectedness along with possible climate change implications, greater potential for weather-relations research is recognized. By drawing attention to weather experiences and understandings alongside resource efficient weather responses, this paper uncovered a substantial capacity among participants to respond sustainably to environmental change. These capacities are the outcome of adjustment practices relating to food, clothing, laundering, physical and outdoor activities, and domestic comfort and a previously unrecognized coping strategy—expressions of tolerance. Findings suggest that by recognizing and fostering existing adjustment capabilities of societies and cultures and the local values that afford their reproduction, communities would be better placed to adapt to future climate change.

Situating 1816, the ‘year without summer’, in the UK

The immediate local impacts of the eruption of Mount Tambora, Sumbawa, Indonesia in April 1815 were devastating, resulting in the loss of an estimated 60 000 lives on this and neighbouring islands. However, the longer term effects of the largest known historical eruption on global weather and climate and the related consequences for human health and wellbeing have maintained the prominence of the eruption in public memory. Among the most notable effects were global weather anomalies the following year, which has come to be referred to as ‘the year without summer’. Scholars across the sciences and humanities continue to investigate the eruption, seeking insights into the likely meteorological and societal impacts of future volcanic eruptions. The bicentenary of the ‘year without summer’ in 2016 provides a timely moment to revisit this weather episode. In this paper, we draw on a range of archival materials and contemporary publications to reconstruct the weather year and explore how the summer of 1816 was experienced and recorded across the UK. We also wish to demonstrate the importance of historical contingency in understanding the potential implications of the event at the local level, and of situating events within their appropriate temporal context. We do this by considering the summer of 1816 as set against the wider weather and cultural contexts of the 1810s. Our findings illustrate that in a UK context, summer 1816 was characterised by unusual and extreme weather events. Importantly it also took place within a sequence of years that were similarly replete with anomalous and challenging weather conditions.

Tony Wilkinson and the water history of the Near East

Water figured centrally throughout Tony Wilkinson’s spectacular career in landscape archaeology in the Near East. His case studies ranged geographically from Yemen to Turkey, Syria to Iran; they included arid desert fringes and (relatedly) moist foothills. The water systems he studied varied in scale from households to villages to states, with a general trend through time from small self-organized systems to massive imperial schemes. Wilkinson drew on any discipline from which data were available, and from which a collaborator or two could be procured. In all cases, however, empirical data from field archaeology held the central position. Despite the scale and number of his projects, collaborations, and students, these field data were overwhelmingly obtained by Wilkinson himself, often under the most challenging weather conditions, made necessary by local agricultural and university academic calendars—negotiating between when fields were clear and courses needed to be taught. Wilkinson often tackled the traces of daily life, the kinds of land use that occurred outside of the interest or notice of the palace elite that have consumed most of the attention of archaeologists. Some of his earliest research investigated falaj (qanat or karez) systems on the Omani coast, which fed sunken fields and powered mills in small oasis towns. He returned to the Arabian peninsula, to trace the small-scale runoff irrigation systems that fed the terraces of highland Yemen. His most widely cited scholarship, however, revolved around the dry-farming agricultural systems that sustained the earliest cities in northern Mesopotamia. He demonstrated how inter-annual variability in rainfall, and householdbased adaptations via manuring, imposed a ceiling on urbanization. Wilkinson’s model

Inventory of Small Forest Areas Using an Unmanned Aerial System

Acquiring high spatial and temporal resolution imagery from small unmanned aerial systems (sUAS) provides new opportunities for inventorying forests at small scales. Only a few studies have investigated the use of UASs in forest inventories, and the results are inconsistent and incomplete. The present study used three-dimensional (3D) variables derived from UAS imagery in combination with ground reference data to fit linear models for Lorey’s mean height (hL), dominant height (hdom), stem number (N), basal area (G), and stem volume (V). Plot-level cross validation revealed adjusted R2 values of 0.71, 0.97, 0.60, 0.60, and 0.85 for hL, hdom, N, G, and V, respectively, with corresponding RMSE values of 1.4 m, 0.7 m, 538.2 ha−1, 4.5 m2∙ha−1, and 38.3 m3∙ha−1. The respective relative RMSE values were 13.3%, 3.5%, 39.2%, 15.4%, and 14.5% of the mean ground reference values. The mean predicted values did not differ significantly from the reference values. The results revealed that the use of UAS imagery can provide relatively accurate and timely forest inventory information at a local scale. In addition, the present study highlights the practical advantages of UAS-assisted forest inventories, including adaptive planning, high project customization, and rapid implementation, even under challenging weather conditions.

Ground-based GNSS ZTD/IWV estimation system for numerical weather prediction in challenging weather conditions

The Global Navigation Satellite Systems (GNSS) are one of the very few tools that can provide continuous, unbiased, precise and robust atmosphere condition information. The extensive research of GNSS space-based segment (e.g. available precise, real-time satellite orbits and clocks), unlimited access to the ground-based Continuously Operating Reference Stations (CORS) GNSS networks along with the well established data processing methods provides an unprecedented opportunity to study the environmental impacts on the GNSS signal propagation. GNSS measurements have been successfully used in precise positioning, tectonic plate monitoring, ionosphere studies and troposphere monitoring. However all GNSS signals recorded on the ground by CORS are subject to ionosphere delay, troposphere delay, multipath and signal strength loss. Nowadays, the GNSS signal delays are gradually incorporated into the numerical weather prediction (NWP) models. Usually the Zenith Total Delay (ZTD) or Integrated Water Vapour (IWV) have been considered as an important source of water vapour contents and assimilated into the NWP models. However, successful assimilation of these products requires strict accuracy assessment, especially in the challenging severe weather conditions.In this study a number of GNSS signal processing strategies have been verified to obtain the best possible estimates of troposphere delays using a selection of International GNSS Service (IGS) orbit and clock products. Three different severe weather events (severe storm, flash flooding, flooding) have been investigated in this paper. The strategies considered are; 1) Double Differenced (DD) network solution with shortest baselines, 2) DD network solution with longest baselines, 3) DD baseline-by-baseline solution (tested but not considered), 4) Zero Differenced (ZD) Precise Point Positioning (PPP) based on ambiguity float solutions, all with precise orbits and clocks, and real time clocks and predicted orbits. The quality of the estimates obtained has been evaluated against radiosonde measurements, Automatic Weather Station (AWS) observations, NWP (assimilation step without ground-based GNSS data) and ZTD estimates from the well established IGS processing centre, the Center of Orbit Determination in Europe (CODE). It shows that the ZTD and IWV estimates from the DD short baseline solution are robust with usually a very small bias (−2.7 to −0.8mm) and errors of less than 10mm (7.6–8.5) (ZTD) or 3mm (2.6–2.7) (IWV). The DD short baseline network solution was found to be the most reliable method in the considered case studies, regardless of the type of orbits and clocks applied.

AERIAL MAGNETIC SENSING WITH AN UAV HELICOPTER

Abstract. This paper concentrates on aerial magnetic sensing with an autonomous Scout B1-100 UAV helicopter. A high-resolution 3-axis mag- netic sensor has been mounted on the helicopter in order to generate a detailed magnetic map and to identify various ferrous objects in the soil. The development is based on advanced mission planning for the UAV as well as test flights under challenging weather conditions such as wind gusts and snow fall. Finally, this paper summarizes a real-world application after the collapse of a daylight coal mining where various persons have been killed and multiple infrastructure objects have been buried. The task of magnetic scanning was applied in order to find buried vehicles where miners have been expected based on eyewitnesses during the collapse. However, while several ferrous objects have been located, the van could not be identified in the extensive area of the landslide.

A Review of Computer Vision Techniques for the Analysis of Urban Traffic

Automatic video analysis from urban surveillance cameras is a fast-emerging field based on computer vision techniques. We present here a comprehensive review of the state-of-the-art computer vision for traffic video with a critical analysis and an outlook to future research directions. This field is of increasing relevance for intelligent transport systems (ITSs). The decreasing hardware cost and, therefore, the increasing deployment of cameras have opened a wide application field for video analytics. Several monitoring objectives such as congestion, traffic rule violation, and vehicle interaction can be targeted using cameras that were typically originally installed for human operators. Systems for the detection and classification of vehicles on highways have successfully been using classical visual surveillance techniques such as background estimation and motion tracking for some time. The urban domain is more challenging with respect to traffic density, lower camera angles that lead to a high degree of occlusion, and the variety of road users. Methods from object categorization and 3-D modeling have inspired more advanced techniques to tackle these challenges. There is no commonly used data set or benchmark challenge, which makes the direct comparison of the proposed algorithms difficult. In addition, evaluation under challenging weather conditions (e.g., rain, fog, and darkness) would be desirable but is rarely performed. Future work should be directed toward robust combined detectors and classifiers for all road users, with a focus on realistic conditions during evaluation.

AMALi – the Airborne Mobile Aerosol Lidar for Arctic research

Abstract. The Airborne Mobile Aerosol Lidar (AMALi) is an instrument developed at the Alfred Wegener Institute for Polar and Marine Research for reliable operation under the challenging weather conditions at the Earth's polar regions. Since 2003 the AMALi has been successfully deployed for measurements in ground-based installation and zenith- or nadir-pointing airborne configurations during several scientific campaigns in the Arctic. The lidar provides backscatter profiles at two wavelengths (355/532 nm or 1064/532 nm) together with the linear depolarization at 532 nm, from which aerosol and cloud properties can be derived. This paper presents the characteristics and capabilities of the AMALi system and gives examples of its usage for airborne and ground-based operations in the Arctic. As this backscatter lidar normally does not operate in aerosol-free layers special evaluation schemes are discussed, the nadir-pointing iterative inversion for the case of an unknown boundary condition and the two-stream approach for the extinction profile calculation if a second lidar system probes the same air mass. Also an intercomparison of the AMALi system with an established ground-based Koldewey Aerosol Raman Lidar (KARL) is given.

HEAVY RAINFALL AND WATERBORNE DISEASE OUTBREAKS: THE WALKERTON EXAMPLE

Recent research indicates that excessive rainfall has been a significant contributor to historical waterborne disease outbreaks. The Meteorological Service of Canada, Environment Canada, provided an analysis and testimony to the Walkerton Inquiry on the excessive rainfall events, including an assessment of the historical significance and expected return periods of the rainfall amounts. While the onset of the majority of the Walkerton, Ontario, Escherichia coli O157:H7 and Campylobacter outbreak occurred several days after a heavy rainfall on May 12, the accumulated 5-d rainfall amounts from 8–12 May were particularly significant. These 5-d accumulations could, on average, only be expected once every 60 yr or more in Walkerton and once every 100 yr or so in the heaviest rainfall area to the south of Walkerton. The significant link between excess rainfall and waterborne disease outbreaks, in conjunction with other multiple risk factors, indicates that meteorological and climatological conditions need to be considered by water managers, public health officials, and private citizens as a significant risk factor for water contamination. A system to identify and project the impacts of such challenging or extreme weather conditions on water supply systems could be developed using a combination of weather/climate monitoring information and weather prediction or quantitative precipitation forecast information. The use of weather monitoring and forecast information or a “wellhead alert system” could alert water system and water supply managers on the potential response of their systems to challenging weather conditions and additional requirements to protect health. Similar approaches have recently been used by beach managers in parts of the United States to predict day-to-day water quality for beach advisories.

Impact-Echo: A method for flaw detection in concrete using transient stress waves: 36741 Sansalone, M.; Carino, N.J. National Bureau of Standards (NEL), Gaithersburg, Maryland (United States), PB87-104444, 236pp. (Sep. 1986). (Not held at Harwell)

Cracks can occur in reinforced-concrete onshore wind turbine foundations due to factors such as the use of substandard concrete mix, mistakes in foundation design or multi-stage concrete pouring under challenging weather conditions. Cracks are routinely identified via above ground inspections and follow-on examination of excavated underground surfaces and are repaired, for example with resin injection and grouting. Their impact on the structure or the efficacy of the repair are often unknown as crack degradation during normal operating conditions is unexplored. In this work, sub-surface cracks in an onshore wind turbine foundation have been instrumented with fibre-optic based strain sensors in an attempt to determine severity and magnitude of deterioration over time. Here we determine cracks monitored show a small magnitude of deterioration over the initial 9-month period after sensor installation, suggesting that repair is not required. We propose a novel methodology for the classification of the types of deterioration evident in cracks as “reactive”, “permanent” and “behavioural”, and demonstrate methods to extract these types of deterioration. Such methods will continually be developed over time as further knowledge of crack behaviour is gained to determine appropriate limits and identify the optimal time to repair.