Space and time are both crucial characteristic dimensions of geographic events and phenomena. Although exploratory spatial data analysis (ESDA) can be used to visualize and summarize complex spatial ...patterns, it has limitations in capturing the temporal dynamics of geographic features. Efforts have been made to incorporate the time dimension into ESDA techniques to detect space-time clustering or trends. Localized space-time statistics that could help in exploratory space-time data analysis (ESTDA), however, are still lacking. Focusing on spatial panel data, our work extended Getis-Ord
and
statistics using a space-time contemporaneous weight matrix and a space-time lagged weight matrix to account for local space-time autocorrelation. Two applications in this article show that the newly developed method can be used to summarize space-time patterns from spatial panel data, identify changes of landscape more consistently, and lend the results readily to visualization.
INTRODUCTION: In the 1990s, Canada, member states of the European Space Agency, Japan, the Russian Federation, and the United States entered into an international agreement Concerning Cooperation on ...the Civil International Space Station. Among the many unique infrastructure challenges,
partners were to develop a comprehensive international medical system and related processes to enable crew medical certification and medical support for all phases of missions, in a framework to support a multilateral space program of unprecedented size, scope, and degree of integration. During
the Shuttle/Mir Program, physicians and specialized experts from the United States and Russia studied prototype systems and developed and operated collaborative mechanisms. The 1998 NASA Memoranda of Understanding with each of the other four partners established the Multilateral Medial Policy
Board, the Multilateral Space Medicine Board, and the Multilateral Medical Operations Panel as medical authority bodies to ensure International Space Station (ISS) crew health and performance. Since 1998, the medical system of the ISS Program has ensured health and excellent performance of
the international crewsan essential prerequisite for the construction and operation of the ISSand prevented mission-impacting medical events and adverse health outcomes. As the ISS is completing its second decade of crewed operation, it is prudent to appraise its established medical framework
for its utility moving forward in new space exploration initiatives. Not only the ISS Program participants, but other nations and space agencies as well, concomitant with commercial endeavors in human spaceflight, can benefit from this evidence for future human exploration programs.Doarn
CR, Polk JD, Grigoriev A, Comtois J-M, Shimada K, Weerts G, Dervay JP, Taddeo TA, Sargsyan A. A framework for multinational medical support for the International Space Station: a model for exploration. Aerosp Med Hum Perform. 2021; 92(2):129134.
Free space optical (FSO) communication technology, also known as optical wireless communications, has regained a great interest over the last few years. In some cases, FSO is seen as an alternative ...to existing technologies, such as radio frequency. In other cases, FSO is considered as a strong candidate to complement and integrate with next-generation technologies, such as 5G wireless networks. Accordingly, FSO technology is being widely deployed in various indoor (e.g., data centers), terrestrial (e.g., mobile networks), space (e.g., inter-satellite and deep space communication), and underwater systems (e.g., underwater sensing). As the application portfolio of FSO technology grows, so does the need for a clear classification for FSO link configurations. Most existing surveys and classifications are single-level classifications, and thus not inclusive enough to accommodate recent and emerging changes and developments of different FSO link configurations and systems. In this paper, we propose a multi-level classification framework to classify existing and future indoor, terrestrial, space, underwater, and heterogenous FSO links and systems using common and simple unified notation. We use the proposed classification to review and summarize major experimental work and systems in the area until 2017. Using the proposed classification and survey, we aim to give researchers a jump-start to tap into the growing and expanding realm of the FSO technology in different environments. The proposed classification can also help organize and systematically present the progress in the research on FSO technology. This makes the identification of the market needs for standards an easier task. Moreover, different entities involved in the standardization process including academic, industry, and regulatory organizations can use the proposed classification as a unified language to communicate during the early stages of standard development which require ambiguity-free discussions and exchange of ideas between different standardization entities. We use the proposed classification to review existing standards and recommendations in the field of FSO. It is also envisioned that the proposed classification can be used as a unified framework to define different FSO channel models for simulation tools.
BepiColombo is a joint mission between the European Space Agency, ESA, and the Japanese Aerospace Exploration Agency, JAXA, to perform a comprehensive exploration of Mercury. Launched on
20
th
...October 2018 from the European spaceport in Kourou, French Guiana, the spacecraft is now en route to Mercury.
Two orbiters have been sent to Mercury and will be put into dedicated, polar orbits around the planet to study the planet and its environment. One orbiter, Mio, is provided by JAXA, and one orbiter, MPO, is provided by ESA. The scientific payload of both spacecraft will provide detailed information necessary to understand the origin and evolution of the planet itself and its surrounding environment. Mercury is the planet closest to the Sun, the only terrestrial planet besides Earth with a self-sustained magnetic field, and the smallest planet in our Solar System. It is a key planet for understanding the evolutionary history of our Solar System and therefore also for the question of how the Earth and our Planetary System were formed.
The scientific objectives focus on a global characterization of Mercury through the investigation of its interior, surface, exosphere, and magnetosphere. In addition, instrumentation onboard BepiColombo will be used to test Einstein’s theory of general relativity. Major effort was put into optimizing the scientific return of the mission by defining a payload such that individual measurements can be interrelated and complement each other.
The International Space Station (ISS) is the largest and most complex international science and technology program in history. As such, it is a laboratory for a myriad of important policy issues. ...These include crisis decision-making. Begun by President Ronald Reagan in 1984, as Freedom, it was rechristened ISS in 1993 by President Bill Clinton. Completed in 2011 under President Barack Obama, it continues to this day and is likely to extend to 2028 and beyond. The ISS represents an international partnership of the National Aeronautics and Space Administration (NASA); Roscosmos, the Russian space agency; the European Space Agency, itself a partnership of 11 nations; the Japan Aerospace Exploration Agency; and the Canadian Space Agency. With NASA as the “managing partner,” the ISS coalition has endured many crises over its long history. One of the most severe came in 2003 when the Columbia Shuttle disintegrated, killing all seven astronauts aboard and grounding the shuttle fleet indefinitely. A crew was on the space station at the time. What was the partnership to do? The Columbia crisis might have torn the partnership apart. It did not and thus presents an opportunity to analyze critical factors in collaboration under stress. The following article uses a process approach to discuss key decisions in the crisis period, from 2003 through 2004. It points to a certain style of leadership as vital, along with several other factors, including interdependency, urgency, rapid decision-making, a plan of action, and political support. These and other elements held the partnership together and kept it going in a common direction. Given the fact that continuing space exploration carries grave risks and is likely to be done through international partnerships, it is highly desirable to draw policy lessons from the shuttle/ISS experience as a guide for the future.
Progress in spaceflight research has led to the introduction of various manned and unmanned reusable space vehicle concepts, opening up uncharted opportunities for the newborn space transport ...industry. For future space transport operations to be technically and commercially viable, it is critical that an acceptable level of safety is provided, requiring the development of novel mission planning and decision support tools that utilize advanced Communication, Navigation and Surveillance (CNS) technologies, and allowing a seamless integration of space operations in the current Air Traffic Management (ATM) network. A review of emerging platform operational concepts is conducted, highlighting both the challenges and the opportunities brought in by the integration with conventional atmospheric air transport. Common launch and re-entry planning methodologies are then discussed, where the physical and computational limitations of these approaches are identified and applicability to future commercial space transport operations is assessed. Attention is then turned to the on-orbit phase, where the unique hazards of the space environment are examined, followed by an overview to the necessary elements required for space object de-confliction and collision avoidance modelling. The regulatory framework evolutions required for spacecraft operations are then discussed, with a focus on space debris mitigation strategies and operational risk assessment. Within the atmospheric domain, possible extensions and alternatives to the conventional airspace segregation approaches are identified including promising Air Traffic Flow Management (ATFM) techniques to facilitate the integration of new-entrant platforms. Lastly, recent modelling approaches to meet on-orbit risk criteria are discussed and evolutionary requirements to improve current operational procedures are identified. These insights will inform future research on CNS/ATM and Avionics (CNS + A) systems and associated cyber-physical architectures for Space Traffic Management (STM).
The development of space robots is vital to broadening human cognitive boundaries. Space robots have been deployed in space science experiments, extravehicular operations, and deep space exploration. ...The application of space robots undoubtedly reduces the risk and cost of space activities. Traditional space robots primarily utilize rigid structures, resulting in limited degrees of freedom, which restricts their operational capabilities. In contrast, soft robots with greater flexibility and robustness may be used for future space exploration. Soft robots applied in space environments must overcome significant challenges associated with ultrahigh vacuum, microgravity, extreme temperatures, and high‐energy radiation. Herein, a comprehensive analysis of the key advantages of soft robots is presented based on the special requirements of the space environments for soft robots. Furthermore, brief insights into how soft robots must be changed in terms of their design, modeling, fabrication, sensing, and control to adapt to space environments are discussed. Specifically, soft robot scenarios with potential space application value are introduced. Finally, opinions regarding the potential directions of soft space robots are provided.
The development of space robots is vital to broadening human cognitive boundaries. Compared with rigid space robots with limited degrees of freedom, soft robots exhibit apparent advantages of dexterity, adaptability, and robustness. Successes such as inflatable antennas have attracted interest in soft space mechanisms. Soft robots are expected to have a role in future on‐orbit missions and planetary exploration.
Delay/disruption-tolerant networking (DTN) is a networking technology conceived to manage opportunistic connections with no consistent end-to-end link connectivity which is common in both terrestrial ...and space communication environments. DTN is recognized as a baseline technology for implementing deep-space networks. Considered as the primary transport protocol of DTN in space, Licklider transmission protocol (LTP) is expected to provide reliable data delivery service in a challenging networking environment regardless of presence of random link disruptions and/or extremely long propagation delays. The National Aeronautics and Space Administration (NASA) has implemented the use of DTN protocols on the International Space Station (ISS) for data delivery to the earth ground station. However, little work has been done in studying the performance of LTP for reliable data/file delivery in such a communication environment, especially in presence of link disruption. There is a lack of a solid performance evaluation of LTP for its use in the space station communications. In this paper, an analytical framework is presented to evaluate the performance of LTP for reliable file delivery between the space station and the ground stations with a focus on the effect of link disruption, which may occur either over the downlink or over the uplink. The effect of data loss due to channel error is also integrated. Realistic data block transmission experiments using a PC-based experimental infrastructure are conducted to validate the analytical models.
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