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Design of microcontroller circuit and measurement software for SiC and MOREBAC experiment / Konstruktion av mikrokontrollerkort och utveckling av mätprogramvara för experimenten SiC och MorebacAndré, Mikael, Paulsson, Hannes January 2016 (has links)
This paper describes the development of an experiment to test the characteristics and functionality of Silicon Carbide (SiC) components in a space environment. The experiment is a part the "Miniature Student Satellite" (MIST) project, and the "Work on Venus" project, both situated at KTH, Stockholm, Sweden The paper primarily covers the development and implementation of the experiments microcontroller and its software, whilst the construction and development of the test circuit for the transistors is carried out at the same time by another team, and therefore described in a separate paper. A microcontroller is selected for this experiment after consideration is taken to both the Low Earth Orbit environment where the experiment will take place, end the power consumption restrictions due to the limited amount of power available at the satellite itself. The software on the microcontroller is then developed to read temperature and voltage input from the different transistors under test, and transform the input data to a readable format sent to the satellites On Board Computer, which can then communicate the readings to the Earth Base Station. Apart from the software of the SiC experiment, a similar software solution on a similar microcontroller is developed for another experiment called MOREBAC, which will be placed on the same satellite. The main difference between the MOREBAC project and SiC in Space will be the type of data read on the input, the number of inputs and the format of the package sent to the On Board Computer. The final stage of the work for this thesis is the design and construction of a Printed Circuit Board. The board contains the microcontroller and connected components, the transistors to be tested, as well as power supplying components, covered in yet another thesis work. / Den här rapporten beskriver utvecklingen av ett experiment vars uppgift är att testa karaktäristiken och funktionaliteten hos Kiselkarbid(SiC)-komponenter i rymden. Experimentet, som går under namnet SiC in Space, är en del av "Minitature Student Satellite"-projektet (MIST), samt projektet "Working on Venus", vilka båda utförs på KTH, Stockholm, Sverige. Rapporten avhandlar huvudsakligen utvecklingen och implementationen av experimentets mikrokontroller samt den tillhörande mjukvaran, samtidigt som testkretsen för den transistor som undersökts utvecklades i ett annat projekt, och är således avhandlat i en annan rapport. En mikrokontroller valdes ut för projektet baserat både klimatet i "Low Earth Orbit" där satelliten kommer att befinna sig, samt de krav som ställdes på strömförbrukningen baserat på den begränsade strömförsörjningen på själva satelliten. Mjukvaran på mikrokontrollern utvecklades sedan för att avläsa temperaturvärden och spänningsnivåer vid testpunkter på transistorerna, för att sedan översätta denna data till ett läsbart format samt skicka den till satellitens omborddator, som i sin tur kan skicka datan till basstationen på jorden. Utöver den mjukvara som utvecklats till SiC in Space, utvecklades även en liknande lösning för ett annat experiment på satelliten, kallat MOREBAC. Den huvudsakliga skillnaden mellan de två mjukvarulösningarna är att de testpunkter som ska läsas av på MOREBAC skiljer sig både i antal och i utförande från de testpunkter som ska läsas på SiC in Space, samt det datapaket som sedan skickas till omborddatorn. Det slutgiltiga steget under detta projekt var sedan att designa och konstruera ett kretskort (PCB). Kretskortet innehåller både den mikrokontroller som avhandlas i denna rapport, transistorerna som ska testas, samt en strömförsörjningslösning som utvecklats i ytterligare ett parallellt projekt.
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Routine omics collection is a golden opportunity for European human research in space and analog environmentsCope, H., Willis, Craig R.G., MacKay, M.J., Rutter, L.A., Toh, L.S., Williams, P.M., Herranz, R., Borg, J., Bezdan, D., Giacomello, S., Muratani, M., Mason, C.E., Etheridge, T., Szewczyk, N.J. 06 October 2022 (has links)
Yes / Widespread generation and analysis of omics data have revolutionized molecular medicine on Earth, yet its power to yield new mechanistic insights and improve occupational health during spaceflight is still to be fully realized in humans. Nevertheless, rapid technological advancements and ever-regular spaceflight programs mean that longitudinal, standardized, and cost-effective collection of human space omics data are firmly within reach. Here, we consider the practicality and scientific return of different sampling methods and omic types in the context of human spaceflight. We also appraise ethical and legal considerations pertinent to omics data derived from European astronauts and spaceflight participants (SFPs). Ultimately, we propose that a routine omics collection program in spaceflight and analog environments presents a golden opportunity. Unlocking this bright future of artificial intelligence (AI)-driven analyses and personalized medicine approaches will require further investigation into best practices, including policy design and standardization of omics data, metadata, and sampling methods. / H.C., R.H., J.B., D.B., S.G., T.E., and N.J.S. are members of the ESA Space Omics Topical Team, funded by the ESA grant/contract 4000131202/20/NL/PG/pt “Space Omics: Towards an integrated ESA/NASA –omics database for spaceflight and ground facilities experiments” awarded to R.H., which was the main funding source for this work. H.C. is also supported by the Horizon Center for Doctoral Training at the University of Nottingham (UKRI grant no. EP/S023305/1). S.G. is supported by the Swedish Research Council VR grant 2020-04864. L.A.R. and M.M. represent the Omics Subgroup of the Japan Society for the Promotion of Science KAKENHI funding group “Living in Space” and are supported by JP15K21745, JP20H03234, and 20F20382. L.A.R. is also supported by the JSPS postdoctoral fellowship P20382. We thank Dr. Sarah Castro-Wallace, the NASA GeneLab Animal AWG, ISSOP, ESA Space Omics Topical Team, ESA Personalized Medicine Topical Team, and Global Alliance for Genomic Health (GA4GH) for useful discussions.
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Operational scenarios optimization for resupply of crew and cargo of an International gateway Station located near the Earth-Moon-Lagrangian point-2 / Optimisation des scénarios opérationnels d’un véhicule de ravitaillement et de transport d'équipage pour la servitude d’une Station Spatiale située au point de Lagrange EML2Lizy-Destrez, Stéphanie 15 December 2015 (has links)
Ce projet se place dans le contexte des futures missions habitées d’exploration du système solaire (avec un horizon de 2025), en respect de la feuille de route proposée par l’ISECG (International Space Exploration Coordination Group) [1]. Une nouvelle avancée serait de maintenir, à un des points de Lagrange du système Terre-Lune, en avant-poste, une station spatiale qui faciliterait l’accès vers les destinations telles que la Lune, Mars et les astéroïdes et permettrait de tester certaines technologies, notamment avant de les employer pour des missions plus lointaines. Un des principaux défis sera de maintenir en permanence et de garantir à bord la santé de l’équipage, à l’aide d’un centre médical (SMC) autonome arrimé à cette station. Se pose alors la problématique de la servitude d’une telle station, pendant la phase de déploiement (assemblage des différents modules constitutifs du centre médical) et la phase opérationnelle. Les enjeux résident, d’un point de vue global, dans la construction des scénarios opérationnels et, d’un point de vue local, la sélection de trajectoires, cherchant notamment à minimiser les incréments de vitesse (la dépense énergétique) et les temps de transport (sauvegarde des équipages). Quelles recommandations pourrait-on apporter en terme d’optimisation de trajectoire, satisfaisant des critères de dépense énergétique, durée de transport et sécurité ? Quels sont les verrous technologiques à lever pour permettre la réalisation d’une telle station spatiale? Quelles seraient les performances à viser pour les sous-systèmes critiques impliqués? Les résultats d’une telle étude permettraient d’ouvrir des perspectives de recherche et développement dans le domaine des vols habités, notamment dans le domaine du transport mais également dans l’optique d’une occupation de longue durée. / In the context of future human space exploration missions in the solar system (with an horizon of 2025) and according to the roadmap proposed by ISECG (International Space Exploration Coordination Group) [1], a new step could be to maintain as an outpost, at one of the libration points of the Earth-Moon system, a space station. This would ease access to far destinations as Moon, Mars and asteroids and would allow to test some innovative technologies, before employing them for far distant human missions. One of the main challenges will be to maintain permanently, and ensure on board crew health thanks to an autonomous space medical center docked to the proposed space station, as a Space haven. Then the main problem to solve is to manage the station servitude, during deployment (modules integration) and operational phase. Challenges lie, on a global point of view, in the design of the operational scenarios and, on a local point of view, in trajectories selection, so as to minimize velocity increments (energy consumption) and transportation duration (crew safety). Which recommendations could be found out as far as trajectories optimization is concerned, that would fulfill energy consumption, transportation duration and safety criterion? What would technological hurdles be to rise for the building of such Space haven? What would be performances to aim at for critical sub-systems? Expected results of this study could point out research and development perspectives for human spaceflight missions and above all, in transportation field for long lasting missions.Thus, the thesis project, presented here, aims at from global system life-cycle decomposition, to identify by phase operational scenario and optimize resupply vehicle mission. The main steps of this project consist in:- Bibliographical survey, that covers all involved disciplines like mission analysis (Astrodynamics, Orbital mechanics, Orthography, N-Body Problem, Rendezvous…), Applied Mathematics, Optimization, Systems Engineering….- Entire system life-cycle analysis, so as to establish the entire set of scenarios for deployment and operations (nominal cases, degraded cases, contingencies…) and for all trajectories legs (Low Earth Orbit, Transfer, Rendezvous, re-entry…)- Trade-off analysis for Space Station architecture- Modeling of the mission legs trajectories- Trajectories optimizationThree main scenarios have been selected from the results of the preliminary design of the Space Station, named THOR: the Space Station deployment, the resupply cargo missions and the crew transportation. The deep analysis of those three main steps sorted out the criticality of the rendezvous strategies in the vicinity of Lagrangian points. A special effort has been set on those approach maneuvers. The optimization of those rendezvous trajectories led to consolidate performances (in term of energy and duration) of the global transfer from the Earth to the Lagrangian point neighborhood and return. Finally, recommendations have been deduced that support the Lagrangian points importance for next steps of Human Spaceflight exploration of the Solar system.
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Impact du stress sur la survie des lymphocytes T CD8+ mémoires dans le contexte des missions spatialesDubeau Laramée, Geneviève 06 1900 (has links)
No description available.
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Understanding the Effects of Long-Duration Spaceflight on Fracture Risk in the Human Femur Using Finite Element AnalysisHenderson, Keyanna Brielle 01 December 2020 (has links) (PDF)
Long-duration spaceflight has been shown to have significant, lasting effects on the bone strength of astronauts and to contribute to age-related complications later in life. The microgravity environment of space causes a decrease in daily mechanical loading, which signals a state of disuse to bone cells. This affects the bone remodeling process, which is responsible for maintaining bone mass, causing an increase in damage and a decrease in density. This leads to bone fragility and decreases overall strength, posing a risk for fracture. However, there is little information pertaining to the timeline of bone loss and subsequent fracture risk.
This study used finite element analysis to model the human femur, the bone most adversely affected by spaceflight, and to simulate the environments of Earth preflight, a six-month mission on the International Space Station, and one year on Earth postflight. Changes in the properties of cortical and trabecular bone in the femoral neck were measured from the simulations, and used to provide evidence for high fracture risk and to predict when it is most prominent.
It was found that a risk for fracture is extremely evident in the femoral neck in both cortical and trabecular bone. Cortical bone in the inferior neck exhibited high magnitudes of damage, while the superior neck suffered the greatest increases in damage that proceeded to increase upon return to Earth. The density of trabecular bone decreased the most significantly and was not fully recovered in the following year. While it is still unclear exactly when these changes cause the greatest risk for fracture, it is possible that they will add to and advance the onset of medical complications such as osteoporosis. Additionally, the results of this study support the claim that the current countermeasure of inflight exercise is insufficient in sustaining bone mass and preserving skeletal health. The effects of long-duration spaceflight on bone health should continue to be investigated especially if future missions are to last as long as one to three years.
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The Role of the Actin Cytoskeleton in Gravity Signal Transduction of Hypocotyls of Arabidopsis thalianaPalmieri, Maria 14 August 2006 (has links)
No description available.
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A Study of International Space Station Ground/Crew Communication Methods with Applications to Human Moon and Mars MissionsEsper, Jennifer Eileen 05 May 2007 (has links)
The International Space Station utilizes many different forms of written and verbal communication between the flight crews and ground control personnel. This study analyzes the historical use of three regular communication methods, Daily Planning Conferences, Weekly Planning Conferences and written Daily Summaries, as well as specific, science and internal maintenance events for characteristics and perceived effectiveness across eight expeditions (4 ? 11). The results are recommendations for the continued use of, or substitution for, these methods for future long-duration human space missions, specifically to the Moon and to Mars. General conclusions are that most of the conference content could have been relayed through written/electronic methods, and that the Daily Summaries are considered succinct and effective as a communication cornerstone. Conclusions formed from the study of individual events involved the importance of well-written crew procedures, the effective stowage and retrieval of necessary materials and the selection of well-defined science experiments.
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A Markovian state-space framework for integrating flexibility into space system design decisionsLafleur, Jarret Marshall 16 December 2011 (has links)
The past decades have seen the state of the art in aerospace system design progress from a scope of simple optimization to one including robustness, with the objective of permitting a single system to perform well even in off-nominal future environments. Integrating flexibility, or the capability to easily modify a system after it has been fielded in response to changing environments, into system design represents a further step forward. One challenge in accomplishing this rests in that the decision-maker must consider not only the present system design decision, but also sequential future design and operation decisions. Despite extensive interest in the topic, the state of the art in designing flexibility into aerospace systems, and particularly space systems, tends to be limited to analyses that are qualitative, deterministic, single-objective, and/or limited to consider a single future time period.
To address these gaps, this thesis develops a stochastic, multi-objective, and multi-period framework for integrating flexibility into space system design decisions. Central to the framework are five steps. First, system configuration options are identified and costs of switching from one configuration to another are compiled into a cost transition matrix. Second, probabilities that demand on the system will transition from one mission to another are compiled into a mission demand Markov chain. Third, one performance matrix for each design objective is populated to describe how well the identified system configurations perform in each of the identified mission demand environments. The fourth step employs multi-period decision analysis techniques, including Markov decision processes (MDPs) from the field of operations research, to find efficient paths and policies a decision-maker may follow. The final step examines the implications of these paths and policies for the primary goal of informing initial system selection.
Overall, this thesis unifies state-centric concepts of flexibility from economics and engineering literature with sequential decision-making techniques from operations research. The end objective of this thesis' framework and its supporting analytic and computational tools is to enable selection of the next-generation space systems today, tailored to decision-maker budget and performance preferences, that will be best able to adapt and perform in a future of changing environments and requirements. Following extensive theoretical development, the framework and its steps are applied to space system planning problems of (1) DARPA-motivated multiple- or distributed-payload satellite selection and (2) NASA human space exploration architecture selection.
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Augmented Reality in Lunar Extravehicular Activities: A Comprehensive Evaluation of Industry Readiness, User Experience, and the Work EnvironmentVishnuvardhan Selvakumar (17593110) 11 December 2023 (has links)
<p dir="ltr">This research explores the potential of AR for lunar missions via the xEMU spacesuit. A market analysis of commercial off-the-shelf AR devices identifies technological trends and constraints that inform the architectural decisions for AR integration with the xEMU. User evaluations in simulated work environments ensure lunar informatics align with crew needs. Drawing insights from human-in-the-loop testing of COTS AR devices, qualitative test results underscore the importance of display optimization, occlusion management, and environmental considerations for enhancing the AR experience during lunar EVAs. Grounded in a task analysis from JETT3 analog testing, crew workflows and communication dynamics are baselined, underscoring the vital role of communication and collaboration. Integrating AR into the EVA work environment holds the potential to streamline decision-making, improve navigation, and enhance overall efficiency, but may come with unintended operational consequences. The human-centered approach prioritizes crew involvement, ensuring that technology remains a facilitator rather than an encumbering element in lunar exploration. The study's significance lies in advancing AR technology for lunar EVAs, guiding hardware design, and enabling seamless integration into the EVA work environment. AR holds promise in reshaping the human-technology relationship, empowering crew members, maximizing science output, and contributing to the next chapter in lunar exploration.</p>
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Spatially resolved gene expression profiling of mouse brain tissue to study the impact of spaceflights / Spatiellt upplöst genuttrycksprofilering av mushjärnvävnad för att studera effekterna av rymdflygningarFrieberg, Paula January 2021 (has links)
Since the first human spaceflight in 1961, hundreds of humans have been in space. Microgravity and high radiation are the main spaceflight hazards. The space environment is known to impact several aspects of human health, such as bone density and cognitive performance. However, the effects of longduration spaceflights on a cellular and molecular level, utilizing biosamples and multiomic approaches, is poorly studied. In this project, the method Spatial Transcriptomics has been utilized to compare brain tissue from the hippocampus region of mice that have been in space with a control group of mice that have stayed on Earth. Spatial Transcriptomics allow for the quantification of gene expression, while maintaining the spatial information of the transcriptome. The results of this study suggest that spaceflights cause mitochondrial stress. This thesis work is part of a more extensive study in collaboration with NASA, and more studies will be conducted to investigate the effects of spaceflights further. If these findings are confirmed, medicines used on Earth to treat patients with mitochondrial dysfunction could increase the wellbeing of astronauts in space. / Sedan den första människan skickades till rymden år 1961, har hundratals astronauter lämnat jordens atmosfär. De mest signifikanta hälsoriskerna i rymden är mikrogravitation och hög strålning och rymdmiljön har stor påverkan på oss. Exempelvis upplever astronauter ofta minskad benmassa och nedsatt kognitiv funktion. Men kunskapen kring hur människor påverkas av långtidresor i rymden är begränsad. Särskilt få experiment har genomförts på stora dataset från biologiska prover, på en molekylär och cellulär nivå. I detta projekt har genuttryck hos möss som varit i rymden jämförts med en kontrollgrupp av möss som stannat på jorden. Metoden Spatial Transcriptomics (ST) har använts för att undersöka vävnadssnitt från hippocampus i mushjärna. Med ST är det möjligt att undersöka RNAmolekyler och kartlägga deras position i vävnaden. Resultatet från denna studie indikerar att miljön i rymden leder till dysfunktion i mitokondrierna. Detta arbete är en del av en större studie i samarbete med NASA och fler experiment kommer genomföras för att undersöka hur vi påverkas av miljön i rymden. Om fler studier stödjer detta resultat, kan mediciner som använts på jorden för att behandla patienter med dysfunktion i mitokondrierna, användas i förebyggande syfte för astronauter.
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