<title>Characterization of the potential impact of space systems on the orbital debris environment: satellite constellations</title>

AbstractIn the last decade, self-healing materials have become extremely appealing for the field of space applications, due to their technological evolution and the consequent possibility of designing space systems and structures able to repair autonomously after damage arising from impacts with micrometeoroids and orbital debris, from accidental contact with sharp objects, from structural fatigue or simply due to material aging. The integration of these novel materials in the design of spacecraft structures would result in increased reliability and safety leading to longer operational life and missions. Such concepts will bring a decisive boost enabling new mission scenario for the establishment of new orbital stations, settlement on the Moon and human exploration of Mars.The proposed review aims at presenting the newest and most promising self-healing materials and associated technologies for space application, along with the issues related to their current technological limitations in combination with the effect of the space environment. An introductory part about the outlooks and challenges of space exploration and the self-healing concept is followed by a brief description of the space environment and its possible effects on the performance of materials. Self-healing materials are then analysed in detail, moving from the general intrinsic and extrinsic categories down to the specific mechanisms.

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The impact of alternative mission models on the future orbital debris environment

Advances in Space Research ◽

10.1016/0273-1177(91)90538-u ◽

1991 ◽

Vol 11 (12) ◽

pp. 29-32

Author(s):

R.C. Reynolds ◽

P.D. Anz-Meador ◽

G.W. Ojakangas

Keyword(s):

Orbital Debris ◽

The Future ◽

The Impact ◽

Orbital Debris Environment

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Radio Frequency Support for Space Systems Based on Multi-Satellite Constellations Taking into Account the ITU-R Requirements and the WRC-19 Results

Rocket-Space Device Engineering and Information Systems ◽

10.30894/issn2409-0239.2021.8.4.72.76 ◽

2021 ◽

Vol 8 (4) ◽

pp. 72-76

Author(s):

А. А. Talanov ◽

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S. А. Fedotov ◽

А. М. Stepanov ◽

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...

Keyword(s):

Radio Frequency ◽

Frequency Spectrum ◽

Communication Systems ◽

Electromagnetic Compatibility ◽

Satellite Communication ◽

Space Systems ◽

Satellite Constellations ◽

Broadband Internet ◽

State Commission ◽

Radio Frequency Spectrum

Deployment of space systems based on multi-satellite constellations to provide broadband Internet access and communication services acutely raises the question of their radio frequency support including issues of electromagnetic compatibility (EMC) between competing space systems using multi-satellite constellations (StarLink, OneWeb, Kuiper, etc.), their EMC with traditional space systems (satellite communication systems that employ spacecraft in geostationary and non-geostationary orbits, space systems of other services), as well as regulatory issues of entering into service and staged deployment of space systems. The article formulates the problematic issues of radio frequency support of modern space systems taking into account the trends of satellite constellations deployment and proposes the solutions with consideration to international and national requirements in the regulation of radio frequency spectrum including the ITU requirements and the requirements of Russian State Commission for Radio Frequencies. The paper shows the ways to share the radio frequency spectrum to meet new requirements of the World Radiocommunication Conference 2019 (WRC-19).

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Single-operator cholangioscopy for diagnosis of cholangioadenoma (bile duct adenoma) and its potential impact on surgical management

Endoscopy International Open ◽

10.1055/a-0743-5386 ◽

2018 ◽

Vol 06 (11) ◽

pp. E1312-E1316 ◽

Cited By ~ 2

Author(s):

John Eccles ◽

Aducio Thiesen ◽

Gurpal Sandha

Keyword(s):

Bile Duct ◽

Surgical Management ◽

Liver Enzymes ◽

Clinical Indication ◽

Targeted Biopsy ◽

Patient Demographics ◽

Single Operator ◽

Potential Impact ◽

Per Oral

Abstract Background and study aims Cholangioadenoma is not recognized commonly and is often only diagnosed on surgical specimens. Direct per oral single-operator cholangioscopy (SOC) allows characterization of common bile duct (CBD) lesions through direct visualization and directed forceps biopsies with potential for impacting surgical management decisions. This is a retrospective review of all SOC cases diagnosed with cholangioadenoma. Patient demographics and outcomes were recorded. Three patients (all male), average age 68 years (range 62 – 76 years), were identified to have a cholangioadenoma. The clinical indication for SOC was deranged liver enzymes with a dilated CBD and a CBD abnormality identified on biliary imaging. The site of cholangioadenoma was proximal, mid and distal CBD, respectively. All patients had a successful SOC with targeted biopsy-proven diagnosis. One patient had a synchronous cholangiocarcinoma and underwent palliative stenting whereas the other two patients underwent appropriate curative resection based on cholangioadenoma location. We conclude that SOC is safe and effective for diagnosis of cholangioadenoma and has potential impact on decisions for surgical management.

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Characterization of a newly established aggregation of the invasive ladybeetle Harmonia axyridis and current status of the invader in Spain

Spanish Journal of Agricultural Research ◽

10.5424/sjar/2015132-7054 ◽

2015 ◽

Vol 13 (2) ◽

pp. e1006 ◽

Cited By ~ 3

Author(s):

Xavier Pons ◽

Meritxell Roca ◽

Belén Lumbierres ◽

Éric Lucas

Keyword(s):

Harmonia Axyridis ◽

Biocontrol Agent ◽

Current Status ◽

Aphid Control ◽

Potential Impact ◽

Overwintering Aggregation ◽

North And South America ◽

First Time ◽

North And South

The multicoloured Asian ladybeetle, Harmonia axyridis (Pallas), an invasive biocontrol agent introduced in North and South America, as well as in Europe for aphid control, drastically affected assemblages of native coccinellid species, local communities and people. Although the insect is common in several European countries and it was released in Spain for aphid control in 1995, no evidence of population establishment has been reported until 2011. In the present paper, 1) we summarize the records of the invasive ladybeetle in Spain and provide numerous new mentions, and 2) we follow for the first time an overwintering aggregation from autumn to spring and characterize some individual features which allow us to determine its phenology of the establishment and spreading. The results establish clearly that: 1) H. axyridis is (until now) restricted to Catalonia (NE Spain) but the invading process is in progress and the insect is able to occupy different habitats; 2) the ladybeetle overwinters successfully in Spain without significant natural mortality or parasitism; 3) the form succinea represents 73-81% of the overwintering individuals, and 4) the invasion takes probably its origin from Southern France. The potential impact of the invasion by H. axyridis in Spain is discussed.

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