Dealing with uncertainties in asteroid deflection demonstration missions: NEOTωIST

AbstractDeflection missions to near-Earth asteroids will encounter non-negligible uncertainties in the physical and orbital parameters of the target object. In order to reliably assess future impact threat mitigation operations such uncertainties have to be quantified and incorporated into the mission design. The implementation of deflection demonstration missions offers the great opportunity to test our current understanding of deflection relevant uncertainties and their consequences, e.g., regarding kinetic impacts on asteroid surfaces. In this contribution, we discuss the role of uncertainties in the NEOTωIST asteroid deflection demonstration concept, a low-cost kinetic impactor design elaborated in the framework of the NEOShield project. The aim of NEOTωIST is to change the spin state of a known and well characterized near-Earth object, in this case the asteroid (25143) Itokawa. Fast events such as the production of the impact crater and ejecta are studied via cube-sat chasers and a flyby vehicle. Long term changes, for instance, in the asteroid's spin and orbit, can be assessed using ground based observations. We find that such a mission can indeed provide valuable constraints on mitigation relevant parameters. Furthermore, the here proposed kinetic impact scenarios can be implemented within the next two decades without threatening Earth's safety.

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A REVIEW ON MECHANICAL PROPERTIES OF NATURAL FIBRE REINFORCED CONCRETE FOR RIGID PAVEMENTS

EPRA International Journal of Research & Development (IJRD) ◽

10.36713/epra8563 ◽

2021 ◽

pp. 266-270

Author(s):

M.Venkata Naga Prasad ◽

Dr.J.Sridhar

Keyword(s):

Low Cost ◽

Natural Fibers ◽

Natural Fibre ◽

Cement Matrix ◽

Rigid Pavements ◽

Steel Bars ◽

Coconut Coir ◽

The Impact ◽

Coconut Fibers

This study focuses on fiber reinforcement, specifically the use of jute and coir as a fiber reinforcing material in concrete. Natural fibers have been used to provide substantial toughness and strength in a very fragile cement matrix composite. It is necessary to make effective changes in this regard. Uses a very alkaline cement matrix to achieve durability. It is preferable to have a chemical composition that is clear. Reinforce the cement and change the surface of the fibers composite. The usage of jute fiber in this article is discussed. Concrete and the impact it has on the characteristics of the concrete it produces, for example this is an attempt to review the work that has just been completed. In the discipline, as well as to establish a foundation for future study in that case. It is critical to create low-cost building and reinforcing techniques that are suited for developing countries. If agricultural by-products like coconut coir can be used to replace steel bars as reinforcement, building costs can be reduced. Down significantly the purpose of this study is to evaluate the characteristics of coconut fibers. Species produced in India and their uses in many fields of engineering, notably civil engineering enhancing the long-term durability of concrete and mortar using engineering as a building material with the addition of coconut fibers the overall objective is to look into the possibility of utilizing domestic resources. Wastes for construction on a tiny scale a review of several researchers’ experiences utilizing is presented in this publication. The performance of coconut coir as a reinforcing component is explored in depth.

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Impact of Thermal Throttling on Long-Term Visual Inference in a CPU-Based Edge Device

Electronics ◽

10.3390/electronics9122106 ◽

2020 ◽

Vol 9 (12) ◽

pp. 2106

Author(s):

Théo Benoit-Cattin ◽

Delia Velasco-Montero ◽

Jorge Fernández-Berni

Keyword(s):

Ambient Temperature ◽

Low Cost ◽

Critical Role ◽

Frame Rate ◽

Raspberry Pi ◽

Maximum Throughput ◽

External Temperature ◽

Active Cooling ◽

The Impact

Many application scenarios of edge visual inference, e.g., robotics or environmental monitoring, eventually require long periods of continuous operation. In such periods, the processor temperature plays a critical role to keep a prescribed frame rate. Particularly, the heavy computational load of convolutional neural networks (CNNs) may lead to thermal throttling and hence performance degradation in few seconds. In this paper, we report and analyze the long-term performance of 80 different cases resulting from running five CNN models on four software frameworks and two operating systems without and with active cooling. This comprehensive study was conducted on a low-cost edge platform, namely Raspberry Pi 4B (RPi4B), under stable indoor conditions. The results show that hysteresis-based active cooling prevented thermal throttling in all cases, thereby improving the throughput up to approximately 90% versus no cooling. Interestingly, the range of fan usage during active cooling varied from 33% to 65%. Given the impact of the fan on the power consumption of the system as a whole, these results stress the importance of a suitable selection of CNN model and software components. To assess the performance in outdoor applications, we integrated an external temperature sensor with the RPi4B and conducted a set of experiments with no active cooling in a wide interval of ambient temperature, ranging from 22 °C to 36 °C. Variations up to 27.7% were measured with respect to the maximum throughput achieved in that interval. This demonstrates that ambient temperature is a critical parameter in case active cooling cannot be applied.

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Privatisation of Housing and the Impact of the Conservative Government's Initiatives on Low-Cost Homeownership and Private Renting between 1979 and 1984 in England and Wales: 3. Impact and Evaluation of Low-Cost Homeownership Policy

Environment and Planning A Economy and Space ◽

10.1068/a180901 ◽

1986 ◽

Vol 18 (7) ◽

pp. 901-911 ◽

Cited By ~ 4

Author(s):

A D H Crook

Keyword(s):

Low Income ◽

Low Cost ◽

Private Renting ◽

Income Groups ◽

Short Run ◽

Low Income Groups ◽

The Right ◽

The Impact ◽

Right To Buy

This is the third in a series of four papers describing and evaluating the British Government's policies of privatising housing. In this paper the research on the short-run impact of the low-cost homeownership programme is examined, by looking at the right to buy, shared ownership, improvement for sale, and homesteading, and at starter homes and licence schemes. The purchasers who have benefited from the programme are identified and the reasons for some of the failures of the policy to reach priority groups and areas of need are examined. An evaluation of the programme is made under three headings: the extent to which new investment is generated, the extent to which benefits are restricted to groups in need, and the long-term consequences of expanding homeownership amongst low-income groups. It is concluded that privatisation cannot be achieved without continued state support and regulation.

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Observations and Recommendations

Cultural Tourism in the Wake of Web Innovation - Advances in Hospitality, Tourism, and the Services Industry ◽

10.4018/978-1-5225-8395-0.ch006 ◽

2019 ◽

pp. 102-113

Keyword(s):

Low Cost ◽

Sustainable Use ◽

Revolutionary Change ◽

Use Of Resources ◽

The Future ◽

The Government ◽

Oil Revenues ◽

The Impact ◽

The City

The future of tourism and communication technology are intertwined. As Toffler observed with other revolutionary change, an inter-relationship will be difficult to predict but rewards will be substantial to those who are ahead of the curve. Two critical forces will continue to collide: increased democratization of tourism and increased focus on sustainable use of resources. The growth in incomes and the expansion of low-cost air service make China, India, and a few other developing countries the most rapidly growing tourism markets. This is particularly the case in parts of the Islamic world, resulting in rapidly expanding numbers of Muslims who seek to undertake the Haj. As detailed in a case study, this has resulted in demolition of much of ancient Mecca to make way for tourist hotels, a case where it appears the Saudi government is more interested in offsetting declining oil revenues with tourism revenues than with preservation of a unique tourism asset. Elsewhere the threat of over-tourism is evident in many places. In Europe, this is most evident in Venice where as tourism has expanded, the prices charged for overnight accommodations have shot up, forcing long-term residents to move out of the city and to endure commutes to their places of work back in the city. Local government has a choice – see the asset degrade or limit tourism. The market is well suited to limit tourism, but if the government imposes fees, say a day pass to enter the city, is this an equitable option (i.e., potentially making the city available only to wealthy visitors)? The nation of Bhutan has already imposed a high fee for visitors as a method to maintain the nation's happiness index. The future of tourism is uncertain as is the impact that technology change and concern regarding sustainability.

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Investigation of Low-Cost and Optical Particulate Matter Sensors for Ambient Monitoring

Atmosphere ◽

10.3390/atmos11101040 ◽

2020 ◽

Vol 11 (10) ◽

pp. 1040

Author(s):

Mariusz Rogulski ◽

Artur Badyda

Keyword(s):

Particulate Matter ◽

Relative Humidity ◽

Low Cost ◽

Reference Station ◽

Correction Function ◽

Maximum Temperature ◽

Large Set ◽

Campaign Evaluation ◽

The Impact

This article presents a long-term evaluation of low-cost particulate matter (PM) sensors in a field measurements campaign. Evaluation was performed in two phases. During the first five months of the campaign, two PM sensors were simultaneously compared with the results from the reference air quality monitoring station in various atmospheric conditions—from the days with freezing cold (minimum temperature below −10 °C) and high relative humidity (up to 95%) to the days with the maximum temperature above 30 °C and low relative humidity (at the level of 25%). Based on the PM10 measurements, the correlation coefficients for both devices in relation to the reference station were determined (r = 0.91 and r = 0.94, respectively), as well as the impact of temperature and relative humidity on measurements from the low-cost sensors in relation to the reference values. The correction function was formulated based on this large set of low-cost PM10 measurements and referential values. The effectiveness of the corrective function was verified during the second measurement campaign carried out in the city of Nowy Sącz (located in southern Poland) for the same five months in the following year. The absolute values of the long-term percentage errors obtained after adjustment were reduced to a maximum of about 20%, and the average percentage errors were usually around 10%.

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Implications of a Soy-Based Diet for Animal Models

International Journal of Molecular Sciences ◽

10.3390/ijms22020774 ◽

2021 ◽

Vol 22 (2) ◽

pp. 774

Author(s):

Justine Dhot ◽

Valentine Prat ◽

Marine Ferron ◽

Virginie Aillerie ◽

Angélique Erraud ◽

...

Keyword(s):

Animal Models ◽

Diastolic Dysfunction ◽

Low Cost ◽

New Drugs ◽

Male Rats ◽

Absolute Requirement ◽

Diet Versus ◽

Bias Attention ◽

The Impact

The use of animal models in fundamental or pre-clinical research remains an absolute requirement for understanding human pathologies and developing new drugs. In order to transpose these results into clinical practice, many parameters must be taken into account to limit bias. Attention has recently been focused on the sex, age or even strain of each animal, but the impact of diet has been largely neglected. Soy, which is commonly used in the diet in varying quantities can affect their physiology. In order to assess whether the presence of soy can impact the obtained results, we studied the impact of a soy-based diet versus a soy-free diet, on diastolic function in a rat model based on transgenic overexpression of the β3-adrenergic receptors in the endothelium and characterized by the appearance of diastolic dysfunction with age. Our results show that the onset of diastolic dysfunction is only observed in transgenic male rats fed with a soy-free diet in the long term. Our study highlights the importance of the diet’s choice in the study design process, especially regarding the proportion of soy, to correctly interpret the outcome as low-cost diets are more likely to be highly concentrated in soy.

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A methodology to quantify and monitor the impact of environmental restoration using climate data records from satellite observations

10.5194/ems2021-9 ◽

2021 ◽

Author(s):

Mendy van der Vliet ◽

Richard de Jeu ◽

Jaap Schellekens ◽

Robin van der Schalie

Keyword(s):

Climate Change ◽

Surface Temperature ◽

European Space Agency ◽

Quality Data ◽

Climate Mitigation ◽

Environmental Restoration ◽

Climate Data ◽

Great Opportunity ◽

The Impact

Environmental restoration has the potential to constrain human-induced land degradation, loss of biodiversity and climate change. Although the practise is increasingly integrated into natural resource and climate mitigation strategies, scientific studies underline that the effectiveness and impact of these restoration projects are currently difficult to monitor and assess. In order to measure the global community&#8217;s progress towards the Sustainable Development Goals (SDGs), restoration interventions need to be assessed in a systematic and objective manner. However, the long-term and high-quality data records that are required for this are often lacking in both time and space. Satellite data products that can detect changes in land use, surface temperature and hydrological conditions over time in a consistent manner, can fill this gap.Over the last few decades, the scientific community has made great efforts to merge different satellites into multi-decadal historical datasets of climate variables. Examples of such long-term climate data records (CDRs) are the soil moisture (from 1978 onwards), land surface temperature (since 1995) and land cover (since 2008) datasets of the European Space Agency Climate Change Initiative (ESA CCI). These consistent datasets, combined with near real-time observations, offer a great opportunity to quantify and monitor the impact of restoration interventions on degraded landscapes. In order to monitor restoration projects affecting areas smaller than the native resolutions of these datasets (up to approximately 25 km), downscaling techniques can be used to increase the spatial level of detail (approximately in the 0.1-1 km range). The resulting monitoring service could help managers of restoration programs and green investment funds to steer decisions and communicate on effectiveness towards their donors.&#160;The satellite datasets were investigated in space and time in relation to the effects of the restoration projects. For each restoration project area, several surface conditions were monitored and compared to those in an unaffected control area to detect and attribute the effects of the restoration program. The present work focuses on several case studies in which the relevance of satellite-based CDRs for the end users&#8217; operational practises related to impact monitoring is assessed in the context of the SDGs 12 (Responsible production and consumption), 13 (Life on land) and 15 (Climate action).

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LICIACube observation capabilities of dust plume evolution after DART impact

10.5194/egusphere-egu2020-19159 ◽

2020 ◽

Author(s):

Vincenzo Corte ◽

Elena Mazzotta Epifani ◽

Elisabetta Dotto ◽

Marilena Amoroso ◽

Simone Pirrotta ◽

...

Keyword(s):

Momentum Transfer ◽

Transfer Efficiency ◽

Mission Design ◽

Binary Asteroid ◽

Space Agency ◽

Asteroid Deflection ◽

High Resolution Images ◽

Binary Asteroid System ◽

Italian Space Agency ◽

The Impact

The NASA Double Asteroid Redirection Test (DART) mission will be the first test to check an asteroid deflection by a kinetic impactor. The target of DART mission is the secondary element of the (65803) Didymos binary asteroid system and the impact is expected in late September &#8211; early October, 2022. The DART S/C will carry a 6U cubesat called LICIACube (Light Italian Cubesat for Imaging of Asteroid), provided by the Italian Space Agency, with the aim to collect pictures of the impact&#8217;s effects. The impact of the 610&#160;kg DART spacecraft at 6.58 km/s on the 163 m Didymos B will result in a change of the binary orbital period of about 10 minutes assuming momentum transfer efficiency &#946; = 1. Values of &#946; > 1 are expected because the produced ejecta carries momentum, primarily in the direction opposite the DART speed direction. The LICIACube mission profile consists in a flyby of Didymos system with closest approach about 3 minutes after the DART impact. LICIACube will be able to acquire the structure and evolution of the DART impact ejecta plume and will obtain high-resolution images and also in 3 colour of the surfaces of both bodies. The nominal mission foresees also imaging of the Dydymos B non-impact hemisphere. The contributions of LICIACube observations to the DART investigations are important for determination of the momentum transfer efficiency &#946;, that is a crucial result of the planetary defence test. Moreover, captured images can enable scientific investigations about the main features of the asteroid system.&#160;In order to check the imaging capability and to optimize the fast scientific phase of LICIAcube, the LICIA team performed several simulations of pictures&#8217; acquisition. In these simulations, considering the specifications of the 2 optical payloads and the foreseen mission design, we reconstructed synthetic images mainly of the plume. As the plume evolution remains the most important uncertainty, since it depends on a very high number of impacting phase parameters, we simulated imaging of different expected evolution behaviours, to obtain instrument operative parameters and to prepare the data analysis. &#160;

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Suppressed, but Not Forgotten

Swiss Journal of Psychology ◽

10.1024/1421-0185/a000033 ◽

2011 ◽

Vol 70 (1) ◽

pp. 5-11 ◽

Cited By ~ 8

Author(s):

Beat Meier ◽

Anja König ◽

Samuel Parak ◽

Katharina Henke

Keyword(s):

Memory Trace ◽

Thought Suppression ◽

Test Phase ◽

Indirect Test ◽

Final Test ◽

Test Experiment ◽

And Control ◽

Cue Words ◽

The Impact

This study investigates the impact of thought suppression over a 1-week interval. In two experiments with 80 university students each, we used the think/no-think paradigm in which participants initially learn a list of word pairs (cue-target associations). Then they were presented with some of the cue words again and should either respond with the target word or avoid thinking about it. In the final test phase, their memory for the initially learned cue-target pairs was tested. In Experiment 1, type of memory test was manipulated (i.e., direct vs. indirect). In Experiment 2, type of no-think instructions was manipulated (i.e., suppress vs. substitute). Overall, our results showed poorer memory for no-think and control items compared to think items across all experiments and conditions. Critically, however, more no-think than control items were remembered after the 1-week interval in the direct, but not in the indirect test (Experiment 1) and with thought suppression, but not thought substitution instructions (Experiment 2). We suggest that during thought suppression a brief reactivation of the learned association may lead to reconsolidation of the memory trace and hence to better retrieval of suppressed than control items in the long term.

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