Low–interfacial toughness materials for effective large-scale deicing

Science ◽  
2019 ◽  
Vol 364 (6438) ◽  
pp. 371-375 ◽  
Author(s):  
Kevin Golovin ◽  
Abhishek Dhyani ◽  
M. D. Thouless ◽  
Anish Tuteja
Keyword(s):  
Adverse Effects ◽  
Large Scale ◽  
Power Lines ◽  
Ice Accretion ◽  
Interfacial Toughness ◽  
Ship Hulls ◽  
Surface Areas

Ice accretion has adverse effects on a range of commercial and residential activities. The force required to remove ice from a surface is typically considered to scale with the iced area. This imparts a scalability limit to the use of icephobic coatings for structures with large surface areas, such as power lines or ship hulls. We describe a class of materials that exhibit a low interfacial toughness with ice, resulting in systems for which the forces required to remove large areas of ice (a few square centimeters or greater) are both low and independent of the iced area. We further demonstrate that coatings made of such materials allow ice to be shed readily from large areas (~1 square meter) merely by self-weight.

scholarly journals Patch antenna sensor for wireless ice and frost detection

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ryan Kozak ◽  
Kasra Khorsand ◽  
Telnaz Zarifi ◽  
Kevin Golovin ◽  
Mohammad H. Zarifi
Keyword(s):  
Resonant Frequency ◽  
Patch Antenna ◽  
Wide Band ◽  
Power Lines ◽  
Ice Thickness ◽  
Ice Accretion ◽  
Robust Method ◽  
Frequency Shifts ◽  
Resonant Amplitude ◽  
Recorded Data

AbstractA patch antenna sensor with T-shaped slots operating at 2.378 GHz was developed and investigated for wireless ice and frost detection applications. Detection was performed by monitoring the resonant amplitude and resonant frequency of the transmission coefficient between the antenna sensor and a wide band receiver. This sensor was capable of distinguishing between frost, ice, and water with total shifts in resonant frequency of 32 MHz and 36 MHz in the presence of frost and ice, respectively, when compared to the bare sensor. Additionally, the antenna was sensitive to both ice thickness and the surface area covered in ice displaying resonant frequency shifts of 2 MHz and 8 MHz respectively between 80 and 160 μL of ice. By fitting an exponential function to the recorded data, the freezing rate was also extracted. The analysis within this work distinguishes the antenna sensor as a highly accurate and robust method for wireless ice accretion detection and monitoring. This technology has applications in a variety of industries including the energy sector for detection of ice on wind turbines and power lines.

scholarly journals Using Participatory Spatial Tools to Unravel Community Perceptions of Land-Use Dynamics in a Mine-Expanding Landscape in Ghana

2021 ◽  
Author(s):  
Jane J. Aggrey ◽  
Mirjam A. F. Ros-Tonen ◽  
Kwabena O. Asubonteng
Keyword(s):  
Land Use ◽  
Adverse Effects ◽  
Large Scale ◽  
Sub Saharan Africa ◽  
Small Scale ◽  
Eastern Region ◽  
Food Crop ◽  
Mosaic Landscape ◽  
Rural Landscapes ◽  
The Future

AbstractArtisanal and small-scale mining (ASM) in sub-Saharan Africa creates considerable dynamics in rural landscapes. Many studies addressed the adverse effects of mining, but few studies use participatory spatial tools to assess the effects on land use. Hence, this paper takes an actor perspective to analyze how communities in a mixed farming-mining area in Ghana’s Eastern Region perceive the spatial dynamics of ASM and its effects on land for farming and food production from past (1986) to present (2018) and toward the future (2035). Participatory maps show how participants visualize the transformation of food-crop areas into small- and large-scale mining, tree crops, and settlement in all the communities between 1986 and 2018 and foresee these trends to continue in the future (2035). Participants also observe how a mosaic landscape shifts toward a segregated landscape, with simultaneous fragmentation of their farming land due to ASM. Further segregation is expected in the future, with attribution to the expansion of settlements being an unexpected outcome. Although participants expect adverse effects on the future availability of food-crop land, no firm conclusions can be drawn about the anticipated effect on food availability. The paper argues that, if responsibly applied and used to reveal community perspectives and concerns about landscape dynamics, participatory mapping can help raise awareness of the need for collective action and contribute to more inclusive landscape governance. These findings contribute to debates on the operationalization of integrated and inclusive landscape approaches and governance, particularly in areas with pervasive impacts of ASM.

scholarly journals Patients’ attitudes toward conventional and herbal treatments for depression and anxiety: A cross-sectional Israeli survey

2021 ◽  
pp. 002076402199238
Author(s):  
Or Burstein ◽  
Alon Shamir ◽  
Nurit Abramovitz ◽  
Ravid Doron
Keyword(s):  
Adverse Effects ◽  
Large Scale ◽  
Prescription Medications ◽  
Depression And Anxiety ◽  
Cultural Backgrounds ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Cultural Aspects ◽  
Final Sample ◽  
Choice Of Treatment

Background: As many patients view conventional antidepressants and anxiolytics negatively, it is not surprising that the willingness to apply these treatments is far from ideal, thus posing a critical barrier in promoting an effective and durable treatment. Aim: The present study aimed to explore patients’ attitudes toward conventional and herbal treatments for depression and anxiety, while considering cultural and demographic factors, to further elucidate the antecedes that putatively determine the treatment’s outcome. Methods: During June 2017, a cross-sectional survey was conducted using stratified sampling from a large-scale Israeli volunteer online panel. The final sample included 591 Jewish Israeli adults that reported they were suffering from depression or anxiety. Results: A heterogeneous range of attitudes toward treatment was found: for example, a large group of patients did not utilize prescription medications (39%), a professional consultation (12.9%), or any form of treatment (17.4%). Interestingly, these patients were significantly more likely to support naturally-derived treatments and were less concerned with scientific proof. Further, adverse effects were demonstrated as a prominent factor in the choice of treatment. A higher incidence of adverse effects was associated with an increased willingness to consider an alternative herbal treatment. Noteworthy attitudes were found in orthodox-Jewish individuals, who showed similar consultation rates, but utilized more psychological, rather than pharmacological treatments. Conclusions: It is proposed that patients’ perspectives and cultural backgrounds are needed to be taken into consideration during the clinical assessment and choice of treatment. The findings imply that a particular emphasis should be placed on patients that discard conventional pharmacological options and on distinct cultural aspects. Several recommendations for revising the current policy are advocated to promote more culturally-informed and patient-oriented care.

scholarly journals Ice-Accretion Test Results for Three Large-Scale Swept-Wing Models in the NASA Icing Research Tunnel

2016 ◽  
Author(s):  
Andy P. Broeren ◽  
Mark G. Potapczuk ◽  
Sam Lee ◽  
Adam M. Malone ◽  
Bernard P. Paul ◽  
...  
Keyword(s):  
Large Scale ◽  
Ice Accretion ◽  
Test Results ◽  
Swept Wing

scholarly journals Mechanical Properties of Protective Coatings against Marine Fouling: A Review

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 173
Author(s):  
Alessandro Pistone ◽  
Cristina Scolaro ◽  
Annamaria Visco
Keyword(s):  
Mechanical Properties ◽  
Large Scale ◽  
Protective Coatings ◽  
Scale Up ◽  
Product Distribution ◽  
Properties Of Coatings ◽  
Fouling Organism ◽  
Ship Hulls ◽  
Marine Industry ◽  
Application Fields

The accumulation of marine organisms on ship hulls, such as microorganisms, barnacles, and seaweeds, represents a global problem for maritime industries, with both economic and environmental costs. The use of biocide-containing paints poses a serious threat to marine ecosystems, affecting both target and non-target organisms driving science and technology towards non-biocidal solutions based on physico-chemical and materials properties of coatings. The review reports recent development of hydrophobic protective coatings in terms of mechanical properties, correlated with the wet ability features. The attention is focused mainly on coatings based on siloxane and epoxy resin due to the wide application fields of such systems in the marine industry. Polyurethane and other systems have been considered as well. These coatings for anti-fouling applications needs to be both long-term mechanically stable, perfectly adherent with the metallic/composite substrate, and capable to detach/destroy the fouling organism. Prospects should focus on developing even “greener” antifouling coatings solutions. These coatings should also be readily addressable to industrial scale-up for large-scale product distribution, possibly at a reasonable cost.

scholarly journals Fault Detection in Power Equipment via an Unmanned Aerial System Using Multi Modal Data

Sensors ◽  
2019 ◽  
Vol 19 (13) ◽  
pp. 3014 ◽  
Author(s):  
Bushra Jalil ◽  
Giuseppe Riccardo Leone ◽  
Massimo Martinelli ◽  
Davide Moroni ◽  
Maria Antonietta Pascali ◽  
...  
Keyword(s):  
Transmission Lines ◽  
Power Plants ◽  
Large Scale ◽  
Infrared Imaging ◽  
Power Transmission ◽  
Video Stream ◽  
Power Lines ◽  
Power Transmission Lines ◽  
Ground Station ◽  
Illumination Changes

The power transmission lines are the link between power plants and the points of consumption, through substations. Most importantly, the assessment of damaged aerial power lines and rusted conductors is of extreme importance for public safety; hence, power lines and associated components must be periodically inspected to ensure a continuous supply and to identify any fault and defect. To achieve these objectives, recently, Unmanned Aerial Vehicles (UAVs) have been widely used; in fact, they provide a safe way to bring sensors close to the power transmission lines and their associated components without halting the equipment during the inspection, and reducing operational cost and risk. In this work, a drone, equipped with multi-modal sensors, captures images in the visible and infrared domain and transmits them to the ground station. We used state-of-the-art computer vision methods to highlight expected faults (i.e., hot spots) or damaged components of the electrical infrastructure (i.e., damaged insulators). Infrared imaging, which is invariant to large scale and illumination changes in the real operating environment, supported the identification of faults in power transmission lines; while a neural network is adapted and trained to detect and classify insulators from an optical video stream. We demonstrate our approach on data captured by a drone in Parma, Italy.

A cost effective approach to stormwater management? source control and distributed storage

1997 ◽  
Vol 36 (8-9) ◽  
pp. 307-311 ◽  
Author(s):  
R. Y. G. Andoh ◽  
C. Declerck
Keyword(s):  
Large Scale ◽  
Traditional Approach ◽  
Distributed Storage ◽  
Cost Effective ◽  
Source Control ◽  
Slowing Down ◽  
Surface Areas ◽  
Cost Effective Approach ◽  
Receiving Waters ◽  
The Cost

Rapid urbanisation and its consequent increase in impermeable surface areas and changes in land use has generally resulted in problems of flooding and heavy pollution of urban streams and other receiving waters. This has often been coupled with ground water depletion and a threat to water resources. The first part of this paper presents an alternative drainage philosophy and strategy which mimics nature's way by slowing down (attenuating) the movement of urban runoff. This approach results in cost-effective, affordable and sustainable drainage schemes. The alternative strategy can be described as one of prevention rather than cure by effecting controls closer to source rather than the traditional approach which results in the transfer of problems downstream, resulting in its cumulation and the need for large scale, centralised control. The second part describes a research project which has been launched in order to quantify the cost and operational benefits of source control and distributed storage. Details of the methodology of the modelling and simulation processes which are being followed to achieve this target are presented.

scholarly journals Simulation-Based Evaluation of the Performance of Broadband over Power Lines with Multiple Repeaters in Linear Topology of Distribution Substations

2020 ◽  
Vol 10 (19) ◽  
pp. 6879
Author(s):  
Petr Musil ◽  
Petr Mlynek ◽  
Jan Slacik ◽  
Jiri Pokorny
Keyword(s):  
Smart Grids ◽  
Large Scale ◽  
Field Measurements ◽  
Lessons Learned ◽  
Power Lines ◽  
Multiple Streams ◽  
Linear Topology ◽  
Performance Improvements ◽  
Multiple Data ◽  
The Impact

Broadband over Power Lines (BPL) is considered a promising communication technology in the concept of Smart Grids. This paper evaluates networks based on BPL, with a focus on the impact of repeaters in the linear topology of distribution substations. In large-scale Smart Grids network planning, positions of repeaters have to be carefully chosen. This article should help to determine such positions and limitations of BPL linear topology networks. Laboratory and on-field measurements and their results are presented in this article. Results show the impact of repeater’s deployment for different testing methodologies also with regard to other already presented studies. Measured values and the determined impacts of repeaters are later used as input data for simulation of the linear BPL topology in terms of network throughput with multiple streams and bottlenecks. These occur especially on lines shared by multiple communicating nodes. Furthermore, the simulation investigates the balancing time of multiple data streams throughput. The simulation shows that the throughput balancing can occupy a significant time slot, up to tens of seconds before the throughput of different streams balances. Also, the more data is generated, the more time the balancing time takes. Additionally, the throughput drop caused by a repeater is determined into the range of 35–60%. Based on the measurement and simulation results, lessons learned are presented, and possible performance improvements are discussed.

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