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The rationality of formulas 22, 27 and 28 in the paper by Qi Zhang et al. (2019) were discussed due to its derivation process. The reason for this irrationality was analyzed in detail and the relationship between RMR 89 and RMR 14 under the condition of considering only discontinuities of rock mass was extracted. On this basis, a more reasonable formula has been proposed to replace formula 22. And another new relationship between R M R 89 and GSI considering strength of intact rock and groundwater has also been put forward. The case study shows that the two formulas proposed in this discussion are applicable. [ABSTRACT FROM AUTHOR]

The global community, with coordination from the United Nations, is energized to pursue the Sustainable Development Goals (SDGs), a list of 17 important aspirations that summarize the key challenges of our era. The SDGs apply to every nation and represent an international effort to eliminate extreme poverty, ensure access to safe drinking water, strengthen food security, and produce clean and reliable energy, among other pursuits. Space technology is already being used around the world to advance progress toward the SDGs and monitor their related Indicators. This paper explores how six technologies related to space—satellite Earth observation, satellite communication, satellite navigation and positioning, human spaceflight and microgravity research, space technology transfer, and basic scientific research—are being used to realize the vision that the SDGs represent. The paper also discusses the obstacles that limit the application of these technologies for the SDGs and provides an overview of potential paths to overcome these barriers. The paper finally studies the historical and potential roles that four distinct types of entities involved in global sustainable development—governments, non- and inter-governmental organizations, entrepreneurial companies, and universities— have played or may play in the application of space technologies towards the SDGs. • Six space technology areas are shown to support the U.N. Sustainable Development Goals. • Examples of space projects that support the SDGs are found in many sectors. • New designs for technology are needed to improve effectiveness of space applications for the SDGS. [ABSTRACT FROM AUTHOR]

• Human resources development aided the developing space program of the Philippines. • Most of the selected personnel for training came from the academia. • Trainees taken from the industry followed later to support the push for space. • Most of trained personnel opted to stay in the country to support the space program. The Philippines has experienced a shift of interest in space technology development and utilization over the past decade, culminating with the establishment of its national space agency in 2019. In cooperation with different universities in Japan, the Philippines successfully developed and launched two microsatellites, DIWATA-1 and DIWATA-2, and six nanosatellites, MAYA-1 to MAYA-6. By sending personnel to Japan and other space-faring countries, the country was able to rapidly ramp up its satellite development and utilization capabilities. In this paper, we examine and evaluate the complex human resources development efforts conducted by the country to support the creation of a local space ecosystem and ensure its long-term sustainability. Through a careful review, we identify how many people benefited from training programs, studies abroad or other forms of capacity building, and how these skilled individuals were retained in the budding Filipino space sector. Precisely, we looked at the backgrounds of the different people trained by the country, what type of training they received (funding, location, and duration), and how they are supporting the local space ecosystem at the time of writing this paper. [ABSTRACT FROM AUTHOR]

The Korea Pathfinder Lunar Orbiter (KPLO), officially named as Danuri, is the Republic of Korea's first spacecraft to orbit the Moon. The goal of KPLO is to secure core deep space technology for future space exploration in Korea and contribute to lunar science by gathering data from the lunar orbit for one year. This paper presents the results of KPLO's Lunar Orbit Acquisition (LOA) phase in detail, with a particular focus on the operational results of Flight Dynamics (FD). During the LOA phase, the KPLO FD team experienced many expected and unexpected issues. These issues were mitigated by making real-time updates to the LOA phase Design Reference Mission (DRM). The paper also presents the results of the Orbit Determination (OD) and performance of each Lunar Orbit Insertion (LOI) maneuver conducted during the actual flight operation. The importance of considering operational constraints when designing the DRM is emphasized by presenting lessons learned based on actual flight experiences. Unlike the original KPLO LOA phase DRM, KPLO successfully achieved the final mission orbit using only three LOI burns, instead of the planned five LOI burns and an Orbit Trim Maneuver (OTM). Despite the extensive revisions made to the DRM, all mission requirements were still fulfilled during the final lunar orbit insertion, taking into account the significant operational constraints. • Real flight operation results of the Korea Pathfinder Lunar Orbiter's lunar orbit acquisition phase are presented. • Orbit determination and lunar orbit insertion maneuver performance are analyzed based on actual flight data. • Unexpected issues during the actual flight operation were mitigated through real-time updates on the design reference mission. • Considering real-world operational constraints while designing the design reference mission is very critical. [ABSTRACT FROM AUTHOR]

There is no doubt that space matters in today's time. We have become highly reliant on space science and technology; life without it cannot be imagined. No one can deny the significance of space safety. Thus, for the smooth functioning of life, there is a need for safety and security in outer space. So, it would not be wrong to say that we are at the mercy of these new space technologies. Currently, space debris has been facing universal embryonic challenge to the sustainable activities of outer space, and if not coped at the earliest, the world would face titanic catastrophe. From the preceding decades, there have been some crashing episodes that heightened the space debris build-up, and the speed at which myriad space activities have caused the production of debris. Such huge congregation of debris can pose dangers to the working space satellites. It could also fetch numerous challenges at the same time. In addition, the tremendous development in space technology, involvement of private sector in space activities, Anti Satellite tests adventure of space powers, weaponization and commercialization (space tourism) has made outer space more vulnerable. Presently, there is a dearth of stringent space laws with regards to the proliferation of space debris. So, these issues can have an impact on the long-term sustainability of space activities. Progressing and advanced space faring nations have found the worth of a proficient International Regime that can play a vital role for ordering, overseeing, and managing the research and advancement of space. The paper will magnet the attention towards the real legal, technical, financial and managerial facts. Some countries are capable of removing space debris but encounter many obstacles while applying such actions. Besides who will bear the expense for the removal of space debris as its prerequisites giant sum of money. This paper is going to put forward an independent international space regime (ISR). In order to meet the financial issues this paper proposed to establish a Global Debris Removal Fund. The old-fashioned space law regime is the core obstruction for the debris removal procedure. Finally, it is desirable that all legal issues be fixed through the innovative procedures and reformed international space law (ISL) system with inclusive coordination and co-operation. Thus, it would be the perfect ISR for the resolutions of remediation and mitigation of space debris. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to study the development of space-age aesthetics culture and arts in seven decades since 1950s. The first known use of "space-age" was in 1946, and was defined as "of, relating to, or befitting the age of space exploration." A more popular definition for the "space age" is "The space age is the time period in human history related to the space race, space exploration, and space technology. Most people say this started when Sputnik 1 was launched in 1957, and continues to today. This has influenced culture such as in movies, television, music, art, and architecture." Culture, in the anthropology, is the patterns of behaviour and thinking that people living in social groups learn, create, and share. Culture distinguishes one human group from others. It also distinguishes humans from other animals. A people's culture includes their beliefs, rules of behaviour, language, rituals, art, technology, styles of dress, ways of producing and cooking food, religion, and political and economic systems. Therefore, the space-age art is one of the major elements of the space-age culture of human beings. On the other hand, the space exploration has significant inspiration and influence on the aesthetics art. In particular, the following aspects shall be studied in this paper: architecture and exhibition craftworks. • The space-age architecture and exhibition craftworks were investigated. • Five space-age architecture shapes investigated are disc, rocket, tower, spherical and combined. • Three space-age installation craftworks studied are sky waves, embroidery, planet models, etc. • Many space-age architectures are destroyed due to many reasons. • Hopefully the young generations can be inspired to carry forward these precious heritages. [ABSTRACT FROM AUTHOR]

• Research on possible scenarios of implementing AI in nanosatellite constellations. • Challenges, applications and possible strategies in Low Earth Orbits, Transfer Region and Lunar Orbits is discussed. • Several examples and major necessities have been included. • Figures portray severe issues to applications and strategic ways to adopt the AI in nanosat constraints is shown in detail. • The future prospects and ways to step-wise organize and implement AI is discussed. The small satellites have been changing the paradigm of space technology and implementation techniques ever since the NewSpace era has begun a stiff competition and dynamic atmosphere for innovation and recreation. Nanosatellites (ranging from 1 to 10 Kg) have been of significant importance since they have been launched and experimented in the past few decades. The constellations of these satellites will be a test of technology and management in due course of time. The complexity of operations and skilled functioning of the satellites in LEO and beyond is becoming crucial for the space industry and scientific communities. This paper will demonstrate the challenges, applications, and strategies to implement Artificial Intelligence (AI) optimally to make these constellations efficient and productive under the given scenarios and constraints. A thorough investigation through literature study has been initially done to observe and monitor the recent developments and envision the futuristic implementation of cognitive computing in CisLunar space. Hence, a detailed description of strategizing this artificial intelligence implementation in three classified regions as Low Earth Orbits (LEO), Transfer Region (TR), and Lunar Orbits (LO) to emphasize their crucial role in operating nanosatellites is significantly presented. [ABSTRACT FROM AUTHOR]

Konstantin Tsiolkovsky famously stated that while the Earth serves as the birthplace of humanity, it is not a place where mankind can indefinitely remain. Perhaps during that period, the prospect of exploring the mysteries of outer space appeared to be an unattainable aspiration. However, in the present day, there are no longer any limitations, not even the sky, since human ingenuity has facilitated access to outer space for humanity. This access is not just for the purposes of research and exploration but also for economic endeavours. Until now, the commercial utilisation of outer space has advanced at a very sluggish rate. However, firms including SpaceX, Orion Span, Virgin Galactic, and Blue Origin have achieved significant advancements in the growth of the space industry. The revenue generated by various space-related endeavours has experienced a significant 73% increase over the last ten years. The global space economy, estimated to be valued at USD one trillion in the coming years, is primarily driven by commercial activities. This presents a formidable challenge to the existing national and international taxation systems. Similar to the open seas, space is also considered res communis omnium, meaning it belongs to the entire community, and presents comparable taxing challenges with potentially uncertain solutions. The three fundamental elements of every taxation regulation, such as the Organisation for Economic Co-operation and Development or the United Nations Model Double Taxation Convention, are the taxpayer's place of residence, the origin of their income, and the methods by which they generate their money. The current tax system does not have the necessary concepts and provisions to adapt to the rapid advancements in commercial space technology. This paper examines the legal issues surrounding commercial activities conducted in space, including the nature and handling of the income generated in various legal systems. It also addresses concerns such as tax avoidance and excessive taxation, emphasising the necessity for a globally coordinated approach to effectively tax commercial activities in space. • Human ingenuity has facilitated access to outer space for humanity, for the purposes of research and exploration and also for economic endeavours. • Space-related endeavours has experienced a significant 73% increase over the last ten years. • Commercial activities conducted in space require concerted action at international level. [ABSTRACT FROM AUTHOR]

• We introduce a graph theory model and utilize dispatchable STN to address the mission planning problem for deep space detectors. • The proposed algorithm efficiently decreases the network scale and streamline the computational workload. • Our proposed algorithm effectively tackles the challenge of dynamic mission scheduling to effectively handle emergencies. Deep space exploration activities can effectively promote the development and application of space technology, which holds significant scientific and strategic value. The multi-mission and long-period detector is executed in deep space, and numerous temporal constraints are generated by mission planning. Moreover, scheduled missions may face external uncertainties, hindering their smooth execution. Therefore, temporal constraint processing strategies that possess dynamic adjustment capabilities play a crucial role in ensuring the successful execution of deep space detectors. Existing methods primarily concentrate on investigating fixed mission series, with limited efficiency in planning. Specifically, these methods do not rigorously enforce temporal constraints and lack the capability to handle the disruptions caused by emergencies, which hinder the smooth execution of planned missions. In this paper, we propose a dynamic temporal constraints algorithm, aiming to efficiently plan missions subject to temporal constraints and let it possess a certain degree of dynamic adjust capability. The simulation results demonstrate the effective simplification of redundant temporal constraints in mission networks by the proposed algorithm. In comparison to the classical algorithm, the computation time exhibits a clear advantage. Furthermore, the proposed algorithm possesses the capability to perform local, small-scale dynamic adjustments in response to emergencies that may disrupt the normal execution of missions. Consequently, this research establishes a robust basis for addressing temporal constraints in deep space detectors. [ABSTRACT FROM AUTHOR]

The Mars rotorcraft is an aerial exploration platform capable of repeated take-offs and landings to extend the range of rover explorations. NASA's Ingenuity helicopter is a full y functioning coaxial helicopter for technology demonstration. Increasing the rotor diameter or the number of blades can enhance the load capacity of the coaxial helicopter but would make it difficult to be folded. A more suitable configuration for Mars exploration is the multi-rotor aircraft, which has a stronger load capacity with the same rotor diameter. Although the aerodynamic performance and operational capabilities of the Mars multi-rotor aircraft have been partially considered, mechatronic system design and autonomous flight control have not been fully addressed. Harbin Institute of Technology and China Academy of Space Technology jointly proposed a deployable Mars quadcopter for air patrol and sampling with a sample mass of 100 g. This paper presents a concept for a Mars quadcopter and its mission operations, including operational procedures and flight modes, to provide a framework for future Mars flight sampling missions. We describe the structure and avionics architecture of the Mars quadcopter. Then, we present the hardware and software design of the guidance, navigation, and control (GNC) system to illustrate the autonomous flight control method. Finally, we introduce the deployment mechanism of the Mars quadcopter. • A foldable Mars quadcopter improves the efficiency and flexibility of Mars sample return tasks. • Five-module avionics system augments the Mars quadcopter for survival and operation. • A navigation method combining inertial and binocular vision enables autonomous flight on Mars. • The guidance system based on mode commands can independently plan exploration operations. [ABSTRACT FROM AUTHOR]

Trends in space technology development and rapidly increasing traffic in outer space are likely to lead to the emergence of a market for services for the removal of large debris objects to disposal orbits. The commercial benefits of Active Debris Removal missions are possible when multiple objects are removed by a single spacecraft-collector that flies between targets in an optimal sequence, trying to achieve a rational ratio between mission duration and fuel costs. Given the size of the large debris population, selecting candidates for removal and optimizing such a mission is a non-trivial task. In this paper, a review of solutions, which are proposed in 65 publications between 2010 and 2023 for the problem of path planning between space debris objects in low orbits, is performed. These solutions could be categorized into three main types. The search for transfer chains in the first type of approaches is based solely on combinatorics, supplemented by various heuristics as required. In the second case, combinatorial-heuristic algorithms fully or partially utilize the secular effects of the Earth's polar compression. Solutions of the third type are based only on the use of precession of the Right Ascension of the Ascending Node of the orbit. For each analyzed work, the following information is given: objects of study, maneuvering scheme for a flight between two successive objects, method of choosing the transfer sequence, and main results. At the end of this paper, a subjective general evaluation of the analyzed works is proposed. In order to deepen the reader's understanding of the problem of large space debris removal, this review also provides background information from related fields. The reasons for the growth of observable fragments in near-Earth space and the need to remove large objects to disposal orbits are shown. The history of experiments aimed at the development of ADR technology is given. The article contains a large number of explanatory illustrations. • The review includes more than 200 research articles on the space debris origin, danger and necessity of ADR. • The study covers 65 papers on ADR path planning published between 2010 and 2023. • The thematic publications are divided into three types depending on the approach to the problem. • The description of each paper contains schemes of maneuvers of an active spacecraft and a method of finding its path. • Analysis of ADR mission parameters shows the advantages of solutions using the RAAN drift. [ABSTRACT FROM AUTHOR]

Deep space exploration technology is an important development direction for scientific exploration. The penetrator method has been proposed as an inexpensive method of studying planetary bodies. The basic principle of this method is that the detection equipment carried by the high-speed penetrator hits a planetary body at a high speed and is buried up to several meters below the surface to carry out detection work. During the frictional collision process with the planets crust, the instantaneous acceleration peaks of the scientific payload (electronic instrumentation) are large. Shock protection of these payloads is necessary to improve their survival and mission success. In this paper, with the goal of improving the survival rate of scientific loads inside a penetrator, a penetrator with a multilayer energy-absorbing structure is developed, in which cushioning protection measures, such as an aluminum foam-filled corrugated tube(AFFT) structure, polyurethane rubber, and epoxy resin potting, are applied to the penetrator. Since the analysis of this process is a highly nonlinear problem, a numerical modeling method is the main approach in this paper. The LS-DYNA software platform was used to simulate the penetrators penetration process on a moon soil medium. The results obtained using empirical formulas and theoretical derivations were compared with the results of numerical analysis to ensure the accuracy of the penetration simulation model. The finite element model of the penetrator was then verified and modified by conducting shock response spectral experiments and shock simulations. The results showed that the spacer scheme had a positive effect on the impact isolation and energy absorption. In addition, this scheme provides an important reference for the design of the penetrator prototype to guarantee the success of subsequent ground rocket sled experiments. • The buffering and energy absorption characteristics of the proposed AFFT structure are analyzed applied to the penetrator. • Through numerical simulation of the penetration process, the initial velocity satisfying the penetration depth was obtained. • The impact response spectrum test and simulation analysis of the penetrator prototype have verified the numerical model. [ABSTRACT FROM AUTHOR]

• Rental housing laundering is subject to care practices and topologies of power. • Social dimensions of communal laundering are at risk. • The concept care could include spatial and temporal aspects. Laundering activities enact a range of socio-material relations and spatialisation of infrastructures such as provision of machines, water, energy, laundry and lately digitalisation. Drawing on a case study on communal laundry facilities in Sweden, this paper focuses on socio-material relations and explores laundry practices in Swedish rental housing, aiming for a theoretical contribution in the field of care, which could incorporate spatial and temporal aspects to be more inclusive. Theoretically based in topologies of power, with sensitivity to processes of spatialisation and temporalities, the analyses show how decisions about design, space and technologies influence everyday life of tenants. The paper illuminates how availability and access to laundry facilities were conformed and individualised to reach expected standards. Laundry spaces were subject to digitalisation and automation technologies introduced to meet efficiency and environmental demands and handle perceived problematic tenant practices. Conclusions are that relational materialism in the field of care and scripting processes would benefit from explicitly including theoretical thinking about space and temporality, conceptualised as choreography. The approach "thinking with care" brought backgrounded laundering phenomena to the fore and pointed out laundering as a matter we should care about. Digitalisation and automation facilitated control of shared laundry spaces and ambitions to individualise laundry made private spaces, such as bathrooms, more attractive to host laundering activities but backgrounded social dimensions of communal laundering. [ABSTRACT FROM AUTHOR]

Private commercial space tourism carrying passengers to outer space is no longer a distant or far-fetched fantasy, rather it is at verge of becoming an affordable reality with exponential development in space technology including development of Reusable Launch Vehicle (RLV), increasing involvement of private companies like Virgin Galactic, SpaceX, Blue Origin etc. into research and funding of space tourism explorations and applications. It is also receiving huge attention from the public. These developments reflect the infinite possibilities and inevitability of space tourism in near future. However, space tourism may also pose many critical legal issues which must be addressed to ensure the consistent and sustainable development of space tourism, and to secure the rights of all stakeholders involved including operators, passengers, launching State etc. The research paper would highlight the crucial legal issues associated with the space tourism. The paper would critically analyze the efficiency of the present international space treaties in dealing with these issues. At the end, the paper would also attempt to provide few suggestions and solutions to these legal conundrums relating to space tourism. • Commercial space tourism • Legal framework governing space tourism • Sustainable development of outer space • Space tourism and international law [ABSTRACT FROM AUTHOR]

• A class of novel deployable units was proposed. • A method of programmatically constructing ring topology was proposed. • DOF of the ring truss deployable mechanism and units were carried out by screw theory. • The kinematic and dynamic models of the deployable mechanism unit were analyzed. • Prototypes of two splicing schemes were manufactured to verify the mobility. With the rapid development of space technology, deployable mechanisms have attracted much attention because of their potential applications. In this paper, novel deployable mechanism units with self-limiting position function are proposed. Then, the ring truss deployable mechanisms are constructed according to two schemes of shared-nodes and shared-edges. The ring truss deployable mechanism constructed using the shared-edges scheme has higher stability, to further expand the application potential of this scheme, a procedural method is proposed to obtain the ring topology with larger aperture. Next the degree of freedom(DOF) of deployable units are analyzed using screw theory, and according to the synchronization between the units, it is proved that the constructed ring truss deployable mechanisms have only one DOF. The dynamic model of the deployable mechanism unit with the passive actuation is established and verified by simulation. Compared with others, the deployable mechanism units proposed in this paper have the advantages of strong scalability and high stability, and they have good application prospect in constructing large deployable mechanisms. [ABSTRACT FROM AUTHOR]

When we talk about Space, our interlocutors think about planets, stars, asteroids, astronauts and, sometimes satellites. But, only a small percentage is aware of what satellite technology can do and the relevance of satellite applications in our everyday life. From satellite communication, to navigation and to earth imagery, satellites data and technology are contributing in improving our daily life, or businesses or helping the management of our cities. Often, the end users come across an obstacle in communicating their needs to the service providers. On the other side, the service providers themselves are not fully aware how to communicate with the end-users. In some cases, this lack of communication makes difficult to meet the demand of space applications from the user side with the supply from the service providers. Eurisy, an association of space agencies established thirty years ago, works to put the end users at the core of the space value chain. In this last decades, Eurisy has been attentive and responsive to the changes of the space sector trying to picture how end users are becoming familiar with space technology. In particular, how the democratisation of space is turning space, especially satellite technology, into an enabler to guarantee the development of a sustainable living, accessible to everyone. Eurisy recently started a review of the case studies collected over the last ten years thanks to direct testimonials, event and conferences, publications and surveys. The user-centred approach adopted is innovative in the space sector and over the years proved to be effective in connecting users and service providers in different contexts. The paper aims at: 1- Identifying challenges and barriers that characterise the relations between service and/or information providers and end users. 2- Analysing the changes occurred in the relations between end users and service providers from 2007 to date in Europe. 3- Presenting the reasons that motivates the use of satellite data and technologies and which of these is the most used. 4- Presenting Eurisy's approach as an applicable model outside the European borders and the benefits deriving from connecting space and society. Furthermore, the paper will briefly present the ongoing activities as examples of the work put in place by the organisation and how the user-centred approach is applied. • The so-called democratisation of space has consequences on the downstream sector. • End users are mostly local and regional public authorities. • Central Europe seems to be the most fertile area where to find use cases. • The main technology adopted is Satellite Navigation. SatComs are not common. • Eurisy works putting the end-users central in the space value chain. [ABSTRACT FROM AUTHOR]

This paper presents the crucial method for the results found at Beijing Institute of Technology and China Academy of Space Technology in the 11th Global Trajectory Optimization Competition (GTOC-11). To build 12 solar-power stations placed in the "Dyson Ring" orbit around the Sun, GTOC-11 focuses on the flyby trajectory design, low-thrust trajectory optimization, and target assignment problem. The mission with time and state constraints causes many difficulties in the design and optimization, which is performed in the following four steps. The first step is to design the orbital elements of the "Dyson Ring" by the grid search method. An approximate model is utilized to evaluate the minimum transfer time for each candidate at first, and the accurate solutions are obtained by the indirect method. The second step involves the Mother Ship trajectories design. A large quantity of earth-to-asteroid and asteroid-to-asteroid subsequences are generated by parallel beam search. The complete trajectories of Mother Ship are designed by connecting the subsequences using beam search. The third step involves the station assignment problem, which is required to design the asteroid transfer device activation epoch and the target station assignment. Based on the results above, the last step involves the rendezvous trajectories optimization to obtain the accurate thrust direction profile. Finally, the submitted and post-competition results are reported. • The simplified and accurate model are proposed to obtain the optimal transfer time. • The parallel beam search is developed to reduce the computational burden. • The station assignment problem is solved by coordinate descent method. [ABSTRACT FROM AUTHOR]

Space can be used as a tool for business decision and policy makers. The maritime sector is rapidly evolving as far as business and industrial activities are concerned. Space can assist in transforming this sector through satellite navigation and positioning, telecommunications and integrated applications as well as earth observation. Additionally, space can be used as a tool in developing, implementing maritime affairs. This paper focuses on the role of space in maritime policy. Space technologies have been serving the maritime community for over fourty years. Satellite technology is becoming increasingly important for a wide range of maritime activities through enhanced navigation accuracy, marine environmental monitoring and maritime surveillance. For this reason, agreements between the European Space Agency (ESA) and the European Maritime Safety Agency (EMSA), have been signed in 2007 and 2010, strengthening the framework for cooperation between the two agencies for the use of space-based systems in support of maritime activities. The first part of the paper summarizes European maritime related policy areas where space assets can contribute to achieve their objectives. The second part of the paper addresses how ESA's initiatives and programs could contribute and support the maritime sector in Europe. The main purpose of this paper is to come up with conclusions on whether and how the use of space assets, technology and applications, can contribute in achieving the maritime policy objectives for the benefit of Europe. • Holistic assesment of the role of space in maritime sector. • Understanding of European maritime related policy areas where space assets can contribute to achieve their objectives. • Identification of particular uses of space assets, technology and applications contributing to maritime policy. • Identification of ESA's initiatives and programs contributing and supporting the maritime sector. • Assessment of the role of space in achieving the maritime policy objectives for the benefit of Europe. [ABSTRACT FROM AUTHOR]

• It is presented a review of the AGAM, showing the classifications and proposed configurations of AGAMs and PAGAMs. • It is studied the effect of low Lift-to-Drag ratios in high altitude AGAM and PAGAM. • It is explored the use of continuum propulsion to null the Drag, improving the gains of energy when compared to GAM. The Gravity Assisted Maneuver has been applied in lots of space missions, to change the spacecraft heliocentric velocity vector and the geometry of the orbit, after the close approach to a celestial body, saving propellant consumption. It is possible to take advantage of additional forces to improve the maneuver, like the forces generated by the spacecraft-atmosphere interaction and/or propulsion systems; reducing the time of flight and the need for multiple passages around secondary bodies. However, these applications require improvements in critical subsystems, which are necessary to accomplish the mission. In this paper, a few combinations of the Gravity-Assist were classified, including maneuvers with thrust and aerodynamic forces; presenting the advantages and limitations of these variations. There are analyzed the effects of implementing low Lift-to-Drag ratios at high altitudes for Aero-gravity Assist maneuvers, with and without propulsion. The maneuvers were simulated for Venus and Mars, due to their relevance in interplanetary missions, the interest in exploration, and the knowledge about their atmospheres. The Aero-gravity Assist maneuver with low Lift-to-Drag ratios at high altitudes shows an increase of more than 10° in the turn angle for Venus and 2.5° for Mars. The maneuvers increase the energy gains by more than 15% when compared to the Gravity-Assist. From the Technology Readiness Levels, it was observed that the current level of development of the space technology makes feasible the application of Aero-gravity Assisted Maneuvers at high altitudes in short term. [ABSTRACT FROM AUTHOR]

The paper investigates the possibility of improving the technology of diffusion welding, which can be used both for joining dissimilar materials for the manufacture of complex devices in the aerospace industry on the ground, and for repair and design in outer space. A laser treatment by nanosecond laser pulses of the ultraviolet range was carried out for surface modification of industry alloys (CrNi55CuВZn, steel AISI 316, Cu–Cr bronze) used in space technology due to high values of thermal and electrical conductivity. It was shown that the preliminary laser treatment leads to an improvement in the properties of the weld: an increase in tensile strength by more than 10%, and tensile strain by more than 20% for certain joints of materials. Also, laser pre-processing can improve the productivity of the welding process, in particular, reduce the temperature and shorten the welding time. • Preliminary laser treatment of alloy samples for diffusion welding was studied. • A method of direct micro- and nanostructuring was used for surface modification. • Laser treatment improves mechanical properties of welded joints used in space and aviation technologies. • Tensile strength increases by more than 10% for joints with treated samples. • Laser pre-processing can reduce the welding temperature and shorten the welding time. [ABSTRACT FROM AUTHOR]

Abstract Attention has been devoted to distributed position and orientation system (DPOS) which can provide high precision spatial and temporal information for all remote sensing loads for airborne multi-task synthetical earth observation system in recent years. Since there are restrictions of space, weight and cost of the DPOS, it is unrealistic to install an IMU of DPOS at the location of each load, and the optimized layout of DPOS has become an urgent problem should be solved. However, there is no report on the optimized layout method for airborne DPOS yet. In this paper, the optimized layout of DPOS is classified as the optimization problem, and two classical optimization algorithms, the genetic algorithm (GA) and particle swarm optimization (PSO), and two novel optimization algorithms, the particle swarm optimization with mutation (PSOM) and hybrid of PSO and GA (HPSOGA), are used and compared for the first time to determine the optimal layout of DPOS. The mathematical simulation shows that the novel method named HPSOGA is superior to the other three methods. In order to accelerate the convergence rate of this layout method, further mathematical simulation and semi-physical simulation based on flight experiment is carried out and the results show that the calculation amount of this method can be reduced by adjusting the individual number calculated by PSO. The work of this paper can provide new ideas and make a good start for the optimized layout study of DPOS. [ABSTRACT FROM AUTHOR]

Highlights • Mission to Mars is currently beyond technological, political, and mental scope of humanity. • There is no one strong rationale for this mission. • Future progress in space technology will be counterbalanced by growing anthropogenic risks including overpopulation, limited resources and climate change. Abstract This paper discusses rationale for human mission to Mars. Human interplanetary mission is still beyond current technological and medical capabilities. But it is also beyond social, political, financial and mental scope of humanity. This paper suggests that it is hard to find any strong rationale for human mission to Mars, which could counterbalance unovoidable risks, threats and costs. [ABSTRACT FROM AUTHOR]

Abstract Italy, as well as many other countries, has increasing interest in Commercial Space Transportation and in particular, in suborbital flights. A suborbital space transportation system is an opportunity to involve the Italian industry in the development of new technologies, exploit opportunities of microgravity experimentation and pilots/astronauts training, as well as catalyse the national industry. The central position of Italy in the Mediterranean basin, the generically favourable climate condition, the touristic vocation resulting in hospitality at the highest level, pretty much allow year round suborbital operations and unique customer experience. Consequently, Italy appears to be a suitable location to host a Spaceport, even though the density of population has to be factored in as a key aspect, together with a proper environmental assessment. This paper outlines the current Italian approach that, instead of focusing on the development of new Spaceport from scratch, evaluates the capabilities of existing airports and their possible upgrades to achieve the Spaceport license, when a proper regulatory frame is established. Advances in the technical activities that are being conducted to assess various Italian sites of interest are described, including trade off methodologies and ranking criteria. Different aspects are considered, from the availability of civil and military airports, to the identification of the best location between coastline or inland sites but, first of all, in compliance to the safety requirements. Some specific Spaceport infrastructure and operational aspects are described, along with their integration with the already existing ones. These include hangars, propellant storage facilities, ground support equipment, high and low airspace surrounding the airport area, ascent and descent corridors, as well as tracking telemetry station to support specific mission profiles in integrated fashion with the existing airport infrastructure and air traffic. The paper will also describe the approach to the definition of a harmonized cooperative regulatory framework, according to the Aviation Authority, that represents the basis to assess suborbital operations and allows the relevant missions execution. In this activity, basing upon an established Memorandum of Cooperation between FAA, ENAC and the Italian Space Agency, the existing FAA/AST regulatory work frame is considered as reference benchmark and further tailored to the Italian case. Some considerations will also be developed relevant to initial challenges to be faced, by interested stakeholders, in starting commercial spaceflight initiatives as a new ground and emerging business opportunity. Highlights • Spaceport and Ground Segment assessment for future suborbital transportation system. • Market opportunities and benefits for the Italian economy. • Spaceport requirements identification for the Italian case. • Spaceport operations business strategy considerations for the Italian case. [ABSTRACT FROM AUTHOR]

The idea of establishing a South American Space Agency (SASA) is not new. There have been many discussions about this topic for a couple of decades, including an agreement by the Union of South American Nations to create such a space agency. Roughly 10 years ago, Argentina was the first to propose this collaboration with a military orientation. As the ideas progressed, Brazil was proposed to host its headquarters. However, not much support from the South American region has been given, either financially or logistically. To this day, a South American Space Agency or a similar concept has not yet been established in the region. The Space Generation Advisory Council (SGAC) hosted the first South American Space Generation Workshop in Argentina in 2015, where one of the working groups was tasked to further investigate the feasibility, advantages and challenges of implementing SASA. This paper presents an extension of the main findings from this working group where South American students and young professionals study and present a rationale in favor of SASA, outlining possible solutions and a structure that could be taken into account for its implementation. This paper pays particular attention to the question: Is it possible for countries in South America to establish the kind of cooperation necessary to stimulate the development and application of capabilities in the space sector, which would then enable undertaking missions far beyond the scope of what any single country in South America could do on its own? The existence of SASA would allow access to a common representative agency, which would lower costs, be accessible to all participating countries, and allow engagement with other emerging and established space agencies around the world. [ABSTRACT FROM AUTHOR]

Abstract: Wernher von Braun''s historic talk at Huntsville on June 7, 1962, when he endorsed “lunar-orbit rendezvous” (LOR) as the mode for landing on the Moon, has long been seen as one of the most critical dates in the Apollo program. It effectively ended a months-long, divisive debate inside NASA over LOR versus “earth-orbit rendezvous” (EOR) versus “direct ascent” (a single huge rocket to launch a lander directly at the Moon, with no rendezvous). Von Braun and his Marshall Space Flight Center had a long-standing commitment to EOR. While historians have long emphasized the significance of this surprise endorsement of LOR, there has been little analysis of how and when he arrived at that decision. This paper will discuss the process by which von Braun finally picked LOR in the spring of 1962 and attempts to pinpoint the date of that decision. However, it also examines his long prehistory of Moon proposals, beginning in public with his October 1952 Collier''s articles. In 1961, after President Kennedy''s endorsement of the Apollo landing goal, he leaned toward EOR primarily because he did not want to build the huge launch vehicle required for direct ascent. He only gradually and somewhat reluctantly changed his mind. How that came about is the fundamental substance of this paper. [Copyright &y& Elsevier]

The International Academy of Astronautics (IAA) Symposia on the History of Rocketry and Astronautics have been held annually at the International Astronautical Congresses since 1967. During these past 50 years nearly 800 papers have been presented and subsequently published in the proceedings. With a 20-year rule imposed for historical presentations, the first 10 symposia concentrated on pre-World War II and early 1950s activities. A surprisingly large number of papers on early, less well-known Soviet-Russian contributions to rocketry and astronautics were presented in the first symposia, despite the ongoing Space Race between the U.S and USSR. Another important element in these symposia involved memoir papers offered by pre- and post-war rocket and astronautics pioneers from many countries, and the participation of many of these pioneers in person. In sum, the history of national space and rocket projects from some 40 countries were presented over the years in IAA History Symposia. These 50 symposia have provided a platform for scholars and professional and non-professional historians to meet and discuss the history of rocketry and astronautics, and to personally interview many space pioneers, most of whom today are deceased. Their personal recollections have since been shared with a large audience. Over time, IAA history papers divided into recognizable periods: ancient times through the 19th century, and the 20th and 21st centuries, which separate among actions and events that took place before 1945, in 1945 to 1957, and after 1957 (which marked the beginning of the space age). Proceedings of the IAA History Symposia have been published in English, ultimately in the History Series of the American Astronautical Society (AAS) and its publishing arm, Univelt Inc., under an agreement secured with the IAA. This paper presents an overview of the IAA History Symposia. It examines the early years of the history committee and its first symposium, the evolution of subsequent symposia, and it recognizes those individuals who shaped these symposia and the publication of its proceedings. [ABSTRACT FROM AUTHOR]

This article discusses the basic philosophy behind India's space strategy based on ideological, sociological, political, economic, geostrategic and legal constructs. The paper uses the metaphor of “deconstruction” made famous by the French philosopher Jacques Derrida's (1930–2004) to understand various transitions (if any) in India's space policy over the years and the philosophy behind them. The paper follows a ‘narrative based scrutiny’ approach to recognise Indian attitude for investments into space technologies. [ABSTRACT FROM AUTHOR]

• Co-production regularly falls short of its transformation ambitions. • Co-production is being stretched beyond the local into global research and technology spaces. • The meaning of co-production is extended in transformative ways in global gene drive. • Transformative ambitions in gene drive'slip' towards reductive framings of collaboration. • Slippage in co-production can be linked to established and new knowledge hierarchies. Co-production is an increasingly popular framework for knowledge generation, evaluation and decision making. Despite its potential to open up decisions and practices to the input of others, co-production regularly falls short of its transformative ambitions. Through documentary analysis, we investigate the meaning and dynamics of co-production as it stretches beyond the local into global research and technology spaces. We find that in the case of global gene drive, the meaning of co-production is extended in novel ways and underpinned by new possibilities for meaningful transformation. At the same time, we also identify a simultaneous resurfacing of reductive framings of collaboration. In the paper we present 'slippage' as a useful heuristic in helping to understand why co-production fails. We argue that if co-production in these new spaces is to achieve its transformative ambitions, there is a need to engage with new and entrenched knowledge hierarchies that contribute to this slippage. [ABSTRACT FROM AUTHOR]

With the development of space technology, the amount of information transmission required by satellites and various spacecraft has increased exponentially. The use of optical communications is a means for future high-speed communications. Adopting superconducting nanowire single photon detectors (SNSPDs) as a receive detector can be capable of detecting signals on the photon scale, which has great application prospects in the field of deep-space optical communication for faint signal detection. However, the use of SNSPDs and high-peak-power optical pulse signals also place higher demands on the extinction ratio of modulators. Therefore, in this paper, we designed a high extinction ratio optical modulator, which adopts cascaded Mach-Zehnder modulators structure, and the static extinction ratio can be reached 77.5 dB. In addition, an SNSPD-based 3.4 km free space optical communication experiment is successfully carried out by using the modulator and a diffuse reflector plate. • A high static extinction ratio optical modulator is designed, and the extinction ratio can be reached 77.5 dB. • SNSPD-based real time FSO experiment is successfully carried out using the modulator and a diffuse reflector plate. • The experiment successfully transmitted live video signals through 3.4 km FSO channels. [ABSTRACT FROM AUTHOR]

The aim of this paper is to optimize reliability and mass of three CO 2 extraction technologies/components: the 4-Bed Molecular Sieve, the Electrochemical Depolarized Concentrator and the Solid Amine Water Desorption. The first one is currently used in the International Space Station and the last two are being developed, and could be used for future long duration missions. This work is part of a complex study of the Environmental Control and Life Support System (ECLSS) reliability. The result of this paper is a methodology to analyze the reliability and mass at a component level, which is used in this paper for the CO 2 extraction technologies, but that can be applied to the ECLSS technologies that perform other tasks, such as oxygen generation or water recycling, which will be a required input for the analysis of an entire ECLSS. The key parameter to evaluate any system to be used in space is mass, as it is directly related to the launch cost. Moreover, for long duration missions, reliability will play an even more important role, as no resupply or rescue mission is taken into consideration. Each technology is studied as a reparable system, where the number of spare parts to be taken for a specific mission will need to be selected, to maximize the reliability and minimize the mass of the system. The problem faced is a Multi-Objective Optimization Problem (MOOP), which does not have a single solution. Thus, optimum solutions of MOOP, the ones that cannot be improved in one of the two objectives, without degrading the other one, are found for each selected technology. The solutions of the MOOP for the three technologies are analyzed and compared, considering other parameters such as the type of mission, the maturity of the technology and potential interactions/synergies with other technologies of the ECLSS. [ABSTRACT FROM AUTHOR]

Terminology is a key issue for a better understanding among people using various languages. Since 1986, when the International Academy of Astronautics (IAA) multilingual terminology database committee on astronautics was formed, the committee and its successor IAA study groups on the IAA multilingual space dictionary have made a continuous effort to construct a multilingual dictionary database on astronautical terms. In 2002, the dictionary was computerized using a database server and some recent internet technologies. The database is accessible from all over the world via the internet. You can search for terms at your home and office using a web browser installed on the computer with an internet connection. Since then, the number of terms and languages included in the database has increased. The current version includes about 3500 terms in 22 languages. The flexibility of the database enables the addition and the revision of new terms without much effort. The computerization has also demonstrated another possibility to utilize the database. When total of four paper books about the multilingual space terminology were published on the 50th anniversary of IAA in 2010, one of the lexicon books was edited by a computer program which accessed to the database. In this paper, the authors present the current status of the IAA multilingual database as well as the future possibilities on the utilization of the database. [ABSTRACT FROM AUTHOR]

Owing to the rapid developments in space technology, there has been a substantial increase in the demand for large-diameter and low-mass space-borne deployable antennas with high geometric stability. To meet this demand, this paper presents a novel single mobility deployable ring mechanism with a high deploy/fold ratio. This mechanism is suitable for constructing large-scale satellite deployable antennas. First, a basic truss element with a low storage height is proposed, and fundamental parameters of the deployable mechanism are analyzed. Second, a general motion analysis model of the deployment process is established, and the corresponding cable-net structure is designed. Finally, a ground experimental prototype with a diameter of 5.0 m is fabricated to demonstrate the feasibility of the proposed mechanism. Based on the experimental results, the feasibility and effectiveness of the novel deployable antenna proposed herein are verified. • A novel single mobility deployable ring mechanism with a high deploy/fold ratio is proposed. • The general model for deployment kinematic analysis is established. • The equal-force form-finding method is applied. • The ground experiment prototype verify the feasibility of the ring deployable antenna. [ABSTRACT FROM AUTHOR]

In this paper, drawn from anthropological research done for a project on Mexican imaginaries of outer space, I consider the role of the AEM, or Mexican Space Agency, in space education and outreach in Mexico, focusing on the ways in which the AEM engages with different sectors and social groups, including elementary age children, college students undertaking STEM careers and artists who use space imagery and technology in their work. The research undertaken for this project consists primarily of formal and informal interviews with key actors engaged with outer space who project space into Mexican futures from different perspectives, from enthusiastic involvement in technological advancement as a means of fomenting social and economic progress, to the artistic uses of space and technology as a means of critically reflecting on earthly issues of human relationality and geopolitical power. In addition to interviews, I draw on information gathered from documents, works of art, online discussion groups and attendance at events sponsored by the Mexican Space Agency. I am particularly interested in exploring the implications of the agency's mission to "promote space culture", as I critically confront anthropological notions of "culture" with the uses of this concept in the public sphere. I am also interested in understanding what is "Mexican" about Mexican space culture, and how national institutions and actors relate to their international counterparts. • Mexico has a nascent space program, but a millennial tradition of stargazing. • The AEM has a strong outreach program, although its public visibility could improve. • Importance of creation of a network of space entrepreneurs, scientists and artists. • Mexicans' outer space imaginaries are diverse, often critical of space exploration. • Anthropology can contribute to the dialogue on the promotion of "space culture. [ABSTRACT FROM AUTHOR]

The Arctic has become an area of particular relevance, where manifold interests meet with particular challenges, such as the harsh environment, a limited infrastructure and a low population density. Since many years, the European Space Agency (ESA) supports its Member States with interests in the Arctic. A variety of ESA programmes are directly or indirectly targeting the Arctic area for scientific purposes, for a better understanding of the Arctic environment or to support other activities in the Arctic region, since many of the specific challenges of the Arctic can be addressed by space technology. Monitoring and assessing the Arctic environment are tasks best met with space systems. Satellite technology facilitates navigation and communication and improves marine safety, and it enables the comprehension of climate change impacts, which are particularly evident and dramatic in the Arctic. While the Sustainable Development Goals (SGDs), which were adopted by UN Member States in 2015, apply globally, the Arctic is especially affected by the changing climate and thus considered to be of great interest to the European and international community. ESA fully supports and works towards attaining the SGDs, and has to this end created a toolbox to target each of the 17 goals. Given the technological capabilities of ESA as well as the Agency's commitment to the SDGs, ESA continues to strengthen its contributions towards a sustainable economic development in the Arctic. After providing a general introduction to the Arctic and its legal status, as well as an overview over different interests in the region, this paper details the numerous ways, in which space activities can contribute to the sustainable development and life in the Arctic. It then turns to retracing the specific steps taken in the European Space Agency, including the work of specific Arctic Task Forces, and gives an outlook on future projects in support of a sustainable Arctic. • The Arctic, heavily affected by climate change, is vital for the global community. • Monitoring and assessing Arctic environment are tasks best met with space systems. • ESA, working on attaining the 17 SGDs, has created a toolbox to target each of them. [ABSTRACT FROM AUTHOR]

The 3U CubeSat OrigamiSat-1 has been developed and launched into orbit in January 2019 to demonstrate a "multifunctional" membrane deployable space structure technology in orbit. Thin-film devices attached throughout the membrane will enable innovative space systems, such as ultralightweight array antennas and solar arrays. The CubeSat's main mission consists of (i) multifunctional membrane deployment mission, and (ii) deployable structure experiment platform mission to enable successive on-orbit demonstrations by CubeSats. This paper describes the significance of these technology demonstrations, and the system design achieved through various prototyping and testing. It also describes the development process and on-orbit operation experience, which will be useful information for other nano-satellite projects that aim at demonstrating innovative technologies actually in space. • OrigamiSat-1 is a 3U CubeSat for the demonstration of a membrane space structure. • Membrane deployment is its primary mission. • Deployable structure experiment platform mission is another object of the satellite. • The satellite's design, development process, and operation experience are provided. [ABSTRACT FROM AUTHOR]

This paper examines the decentralization of European space technology research and development through the joint lenses of policy, systems architecture, and innovation contexts. It uses a detailed longitudinal case history of the development of a novel astrophysics instrument to explore the link between policy-imposed institutional decomposition and the architecture of the technical system. The analysis focuses on five instances of collaborative design decision-making and finds that matching between the technical and institutional architectures is a predictor of project success, consistent with the mirroring hypothesis in extant literature. Examined over time, the instances reveal stability in the loosely coupled nature of institutional arrangements and a trend towards more integral, or tightly coupled, technical systems. The stability of the institutional arrangements is explained as an artifact of the European Hultqvist policy and the trend towards integral technical systems is related to the increasing complexity of modern space systems. If these trends persist, the scale of the mismatch will continue to grow. As a first step towards mitigating this challenge, the paper develops a framework for balancing upfront decomposition and in-process coordination in collaborative development projects. The astrophysics instrument case history is used to illustrate how collaborations should be defined for a given inherent system complexity. [ABSTRACT FROM AUTHOR]

This paper presents the practice of the artist/researcher Ioannis Michaloudis. It showcases his use of a space technology nanomaterial, silica aerogel, and its potential in the cultural utilization of space. Since 2001, his projects have centered around the esthetic, sculptural and conceptual use of silica aerogel. For Michaloudis, this material is highly allegorical of what he terms ‘our breaking sky’. For the authors, the step towards space is a real ‘bridge moment’, analogous to the evolutionary progression of organisms from water to earth. In this current era of space exploration, it is clear that humans need to develop new organs and survival skills – or, cultivate new skies in response to the breaking of our atmosphere׳s dome. It is also clear that science and art need to collaborate more productively. To this end, it is argued that allegory provides the link between imaginability, experiment and representation in both scientific and artistic practices. Etherospermia (εθεροσπερμία) is an invented word from ether and panspermia . The Etherospermia project pursues, allegorically, the creation of new atmospheres on other planets, in order to draw attention to the degradation and destruction of the earth׳s protective veil. Imagine an astronaut who, during a space walk, scatters fragments of Michaloudis׳ silica aerogel as seed material to alter the atmospheres of other planets, making them habitable. The paper discusses nine artworks as a way of presenting the conceptual core of the etherospermia allegory. [ABSTRACT FROM AUTHOR]

Long Duration Balloon missions are key platforms for scientific research and space technology development. Thermal analyses of this kind of systems are crucial for the success of the mission. Even though the science is usually performed at float altitude, the ascent phase, usually non-operational, is where the extreme cold conditions occur, due to the convective effects caused by relative wind speed together with the low temperatures found in the tropopause, making this scenario a dimensioning case. In this paper, a thorough study of the thermal environmental conditions during the ascent is carried out, in particular winds, temperature, and radiative thermal loads have been obtained as a function of the altitude. The study is based on real data obtained from different sources, including atmospheric soundings, radar and satellite, and a meticulous statistical treatment. The study is focussed on one of the main stratospheric balloon launch sites in Europe, Esrange (Sweden), a center of the Swedish Space Corporation, and the analyses are performed for the summer period. However, the methodology can be extended to any other location and epoch. As an example, the convective effect of the horizontal winds on a plate has been studied, and the heat transfer during the ascent phase has been quantified. A subcooling of around 7 °C was found in this case, which make worth the dedicated analysis. • Real data-based thermal environment for Long Duration Balloon missions. • Thermal influence of the high winds found in the tropopause. • Radiative thermal environment parametrized as a function of the Solar Zenith Angle. • Results compared with traditional methodologies. • Convective and radiative heat transfer quantification during the ascent phase. [ABSTRACT FROM AUTHOR]

• This paper summarizes the previous and recent advances of ZnO-NWs. • The work unraveled the benefit of irradiation on ZnO-NWs in harsh environments. • The effects of various energy photons where discussed. • Irradiated samples help in optimizing the properties of ZNO-NWs. It is a misunderstanding that higher energy ion irradiation on nanomaterials has only detrimental effects on their properties. Recent research reveals that higher energy irradiation on nanostructure materials is favorable with advantageous effects. Light, medium, heavy ions, and high energy photons serve as a veritable tool to synthesized nanowires for these effects. In this article, experimental research on the impact of ion species and high energy photons irradiation on structured ZnO nanowires (ZnO-NWs) and at different ion energies (keV to MeV), ion fluences, and substrate temperatures are discussed. The study has revealed that ZnO-NWs structures were damaged at high irradiation fluence under room temperature. Moreover, the porous structures of ZnO-NWs are created by light ions irradiation at a higher temperature. It is noteworthy that the effect of these irradiation beams induced-cutting of ZnO-NWs and fabrication of nano-holes in ZnO-NWs valuable for nano-devices in space technology under harsh environment. [ABSTRACT FROM AUTHOR]

• The proposed control framework mitigates assumptions about accurate physical models. • A novel exploration mechanism incorporates historical information representation. • Each MG controller can manage the energy of MG in a decentralized manner. Reliability and cost-effectiveness in the operation of the multiple microgrid (MMG) system depend on the skillful management of its energy resources. Traditional energy management approaches are physics-model-based, which rely on the precise system parameters (e.g., line parameters) of the electricity and heat network. It is difficult to establish the precise system parameters in practice because they depend on a variety of factors. In this context, this paper proposes a physics-model-free control framework for the energy management of MMGs with heat-electricity energy, consisting of proposed surrogate model and multi-agent deep reinforcement learning (MADRL) approach. An important step is to use historical data to train a surrogate model in supervised manner that can imitate the realistic power and thermal flow calculations. Meanwhile, the energy management problem is reformulated as a Markov game. It is solved by the proposed MADRL-based approach by modeling each MG controller as an agent with a specific objective. The historical trajectories representation, parameter space technology, and deep dense architecture in reinforcement learning are introduced in MADRL to overcome the negative impact brought by the time series data from the input state on the decision-making process and construct an efficient exploration mechanism to overcome inefficient optimization of the MMG system in a multi-agent setting. During training period of MADRL, the trained surrogate models integrate into the environment of the MADRL, which can develop optimal energy management strategy based on the continuous interaction with the surrogate models. The proposed surrogate model enabled MADRL approach can reduce the reliance on precise physical systems and prevent having an impact on the real system while being trained involving trial and error process. Simulation results demonstrate the effectiveness of the proposed control framework. [ABSTRACT FROM AUTHOR]

Abstract: This paper analyzes Colombia׳s space policy: its successes, its failures and what it still needs to achieve. The paper examines the interaction among the different players, and how this policy contributes to economic and social development of the country. And postulates that, unless a real national plan of action, with specific milestones and budget as well as a managing agency are developed, this policy may be in danger of disappearing. The Colombian Space Commission (Comisión Colombiana del Espacio, or CCE) was created by Presidential Decree 2442 in 2006. It is a multi-sectorial entity, in charge of coordinating, planning, and leading in the implementation of national policies for the development and application of space technologies. The CCE was also charged with the drafting of plans and programs in this field. The CCE began with only a few members (15) and today is comprised of 47 members: 13 ministries, 4 administrative departments, another 21 governmental entities and 9 universities, the latter acting as consultants. The Vice-President of the Republic is the President of the CCE. These different actors gave great importance to the development of Colombia׳s space sector, and 6 years later, they are continuing support and development the country׳s space policy. This analysis takes into account three aspects: first, achieving the objectives of the CCE: the creation and development of a national space policy for Colombia; secondly, focussing on “target groups” and “end users”; and thirdly, the “outcomes” or achievements to date. Some conclusions are worth highlighting: first, the warm reception and support of the CCE by both the public and private sectors on high levels, but the poor knowledge of the national space policy by the Colombian people and the small and medium companies. Secondly, in the context of public policy [9], the strategic plan called “National Policy in regard to Space Activities”, is caught between two phases: the formulation and decision-making regarding the program, and its implementation. And finally, the members of the CCE do not necessarily act in accordance with a national strategy, but follow their own interests, resulting in undue influence (and perhaps interference) in the development of a coherent national space policy. In brief, the author hopes that this first analysis of Colombia׳s experience with its Space Commission will serve as an example to other developing countries that also are seeking to develop their space sector, and implement a national space policy. Further, the author hopes that this analysis will allow the various politico-administrative actors “policy makers” in Colombia, as well as the general public, to realize that, while much has been accomplished, much still remains to be done. It is essential to keep alive the interest shown in space activities; otherwise, Colombia׳s space policy may become an “endangered species”, in danger of failing and disappearing. [Copyright &y& Elsevier]

Abstract: India in Asia and Brazil in Latin America are regarded as the most promising global economies. This paper examines the openings and possibilities for space technology collaboration between India and Latin American states under the larger rubric of science and technology collaboration. While the distance and language barriers between the two regions have proved a hindrance in the past, the paper proceeds with an assumption that, in the 21st century, such barriers should not be a limitation on developing strategic, economic, and science and technology partnerships among nation-states. The paper argues that the Latin American states are keen to have their own satellites because of their significant utility in the socioeconomic sector and this offers an opportunity to India to use cooperation in space technologies as a powerful tool for engagement in Latin America. [Copyright &y& Elsevier]

Abstract: Countries on every continent are making new or renewed commitments to domestic satellite programs. These programs have the potential to address national needs by enhancing access to information, improving infrastructure and providing inspiration to the public. How do countries without local expertise in space technology begin a new satellite program? What is the role of international collaboration in supporting the efforts of a new space fairing country? This paper explores such questions by highlighting outputs from intensive field work in Africa and Asia. Specifically, the study explores case studies of early space activity in these countries to search for lessons about the management of a young space program. The observations from field work are compared to ideas from scholarly literature on technological learning. The findings are organized using principles from systems architecture. The paper presents a model that captures many of the influences and strategic decision areas for a collaborative satellite development project. The paper also highlights the growth of capability among African countries in the area of satellite technology. [Copyright &y& Elsevier]

Abstract: Government organizations have to justify high expenditure during periods of financial crisis such as the one we are experiencing today. Space agencies have attempted to increase the returns on their investments in space missions by encouraging the commercial use of advanced technologies. This paper describes two technology transfer (TT) cases promoted by JAXA, in order to identify the organizational models and determinants of TT. The development of a TT process from space to Earth not only benefits the aerospace industry but also the network of national companies. The aim of the paper is to investigate who the actors are and the nature of their role, as well as the determinants of the TT process in the Japanese space sector. The case studies confirm the typical path of transfer as ‘Earth–space–Earth’. [Copyright &y& Elsevier]

Abstract: Power-limited systems with variable Isp, which have been studied theoretically since the beginning of astronautics, are getting closer to practical applications thanks to recent technological advances in the field of magnetosplasma rockets, such as Ad-Astra’s VASIMR concept. This type of propulsion system is considered for high-speed interplanetary transfers, such as Mars missions, with demanding payload fractions that would be compatible with manned missions. This paper explores the problem of the optimization of a power-limited propulsion system through simple performance models, and investigates the trade-off between the technological requirements, the transfer time and the payload fraction 1 [1] The work presented in this paper has been funded by the French space agency CNES. . Following previous works existing in literature, we model the technological characteristics of the vehicle through a small number of parameters, the most important of which being the specific weight (or mass-to-power ratio) of the power generation system. Also, we use in our models the classical “trajectory characteristic” parameter (defined as the integral over time of the squared thrust acceleration) which represents – under certain hypotheses – the propulsion requirements for an orbital or interplanetary transfer with a given time and a given thrust strategy. In this paper, we first give a review of existing methods in literature, then we present the equations of a new class of optimal design which maximizes the payload fraction, for a given transfer time and given technological characteristics. This class of optimal design is described through very simple equations that make possible to study more straightforwardly than existing calculations the links between the main mission requirements (transfer time and payload fraction) and the main technological requirements (specific weight of the power generation and structure mass ratio of the whole vehicle, excluding the power generation system). One important result obtained from these equations is a simple expression which estimates the theoretical upper limit of the power source’s specific weight as a function of transfer time and the payload mass ratio. In the last part of this paper, we apply this simple performance model to discuss the feasibility of a fast Earth-to-Mars transfer using a power-limited system. [Copyright &y& Elsevier]

Abstract: Science and technology satellite-3 (STSAT-3) is being developed and is scheduled for launch in 2011. One of the primary objectives of its mission is to verify the performance of a hall thruster propulsion system (HPS) that uses xenon gas. According to its major functions, the HPS can be divided into several sub-modules. This paper presents the development and qualification of the hall effect thruster propulsion subsystem that includes a xenon feed system (XFS). The xenon feed system regulates the pressure down from the xenon propellant tank and supplies the xenon flows to the anode and cathode. The technology and xenon feed system developed for the STSAT-3 spacecraft will also be applicable to a variety of future electronic propulsion systems and micro-satellites. Details related to the overall development and performance results of the HPS are presented in this paper. [Copyright &y& Elsevier]

Abstract: Several small remote sensing satellites have been developed and launched during the last decade by several developing countries in Africa, the Middle East and East Asia. These satellites share among them several features; chief among them is that they were developed for use in developmental planning and to gain access to space technology. The first generation of those satellites had a relatively course resolution of about 30m, but the second generation reaches a resolution of 2.5m. This group of satellites also have “similar” designs, which stems from the fact that they were developed to achieve a similar purpose: introducing developing countries to space technology and application through small remote sensing satellites. The other side of building national space programs in developing nations is building the technological base for satellite manufacturing, building the infrastructure for operation and utilization of these satellites and most importantly building the user community and the user applications, which uses these results for sustainable development. This paper attempts to assess the degree to which these objectives were achieved for various satellites. In addition to these more “programmatic” aspects, the paper attempts to shed light, from published information, on some aspects of the recent trends in designs of small remote sensing satellites. [Copyright &y& Elsevier]