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In March 2007 five satellites were launched as part of the NASA mission THEMIS. The aim of the mission is to answer the unknown questions regarding the onset of substorms. THEMIS data has also been used within other research fields. Today many scientists aim to investigate wave phenomena, such as whistler waves, wave interactions in the radiation belts and general turbulence in the magnetosphere and the solar wind. These processes occur at intermediate frequencies (a few hundreds of Hertz). Correct and reliable results require good knowledge of the frequency response,  the so called transfer function, for the electric field instrument (EFI). Post-launch calibrations have given good knowledge of the instrument's response at high and low frequencies. However, at intermediate frequencies (50-3000 Hz) the transfer function has only been determined via calculations/simulations and not yet obtained from data collected in space. Moreover, the transfer function changes substantially in this range, as the instrument transitions from a resistive low-frequency coupling to a capacitive high-frequency coupling. The transition is known as the RC roll-off. In this thesis, data from different regions and with different electrical settings have been analyzed to estimate the EFI sensors' sheath impedance and transfer function. Data have been collected during July 2009 and March 2011. From the first period, I-V curves where extracted for four different regions (i.e. with different plasma conditions) and their associated sheath impedance calculated. I-V curves are graphical representations of how the voltage differs with the changed bias current. From the sheath impedance and the measured free-space capacitance the RC roll-off can been directly calculated. An experiment was also conducted in March 2011 where the instrument was run in a special mode designed to measure the relative transfer function with the probes run at different bias setting, yielding different sheath impedances. The analysis of the I-V curves and relative transfer function show similar results, which clearly differ from the earlier believed values. Values for the sheath impedance are lower (4-6 MΩ) than the expected (30 MΩ) and depend on the usher setting. The usher is an electronic device which should shield the sensor from the photoelectron produced by illumination of the preamplifier. This lower sheath resistance implies higher than expected RC roll-off frequency, a result which is confirmed by the results from the relative transfer function. The roll-off is between 2-3 kHz, compared to the 400-500 Hz assumed prior to this study based on the assumption of a sheath impedance of around 30 MΩ.

My dissertation details the work I have done related to remote sensing of thermal activityon Io and thermal remote sensing used in the search for oases on Mars. At Io, I studiedtwo volcanoes, Tvashtar and Prometheus and their thermal activity. At Mars, I investigatedsuggestions of a possible oasis in one of the youngest volcanic regions, Cerberus Fossaeand nearby areas of SE Elysium.Tvashtar was the site of the first high-spatial-resolution observation of an extraterrestriallava curtain. The Tvashtar complex was also the site of a large, confined eruption a fewmonths after the fissure eruption. I discuss the work involved in estimating the brightnesstemperatures and power output of both eruptions as seen by the Galileo SSI. I also discusscooling and eruption-style models and their application to Tvashtar. In every geometricallycorrect observation of Prometheus, we have seen a 100 km tall SO2 gas and dust plumeabove its flow field. This plume and field migrated ~80 km between the Voyager and Galileo eras. I describe the work I performed in modeling the plume's creation as lava-volatileinteractions at the flow fronts.My Mars research entailed the search for thermal systems and constraints on nearsurfacewater ice in an equatorial region that contains some of the youngest lava flows onMars. This region, SE Elysium, also shows evidence of contemporaneous water and lava. Life as we know it requires a source of energy and liquid water, so a geologically youngregion containing both water and energy is an obvious place to study. I show, however, thatthe recent suggestions of extant near-surface water ice and possible endogenic energy escapeare not necessary, and that the thermal imaging of the region requires rock rather thanwater ice near the surface. I also show that the current instruments at Mars are insufficientfor the remote discovery of thermal reservoirs and then discuss some possible remedies.

The design of complex systems such as a launcher, or subsystems like its pressurization system, is known to be fastidious and expensive especially in the space domain. However, the recent emergence of new actors in this domain has been a game changer, binding these systems to fulfil more and more requirements (cheap, efficient, rapidly produced, aesthetic, environmentally friendly…) in order to compete with the market. For these reasons, engineers now need more than ever to consider the full picture of a system or subsystem in order to optimize it. In this context, this document aims to present the method and the results obtained in the optimization of the pressurization system of a reusable rocket first stage named Themis 3. The modelling of the pressurization system has been realized through a software called Geeglee. In order to cover as many impacts of this system as possible, an important part of the rocket stage has been considered and modelled (from the pressurization gases to the propellant tanks, passing by the pressurant and propellant feeding lines). Three High Level Requirements (HLR) have been identified as of major importance for the trade-off in the design of the pressurization system: the total mass impact, the total Recursive Cost (RC) impact and the total Non-Recursive Cost (NRC) impact. This optimization has in particular permitted to confirm some well-known results, so to say that exogenous pressurization systems represent a smaller mass impact on the vehicle, at the expense of a higher RC compared with autogenous systems. / Utformningen av komplexa system, som till exempel en bärraket, eller delsystem som dess trycksättningssystem, är känd för att vara krävande och kostsam, särskilt inom rymdteknikområdet. Den senaste tidens uppkomst av nya aktörer på detta område har dock förändrat spelregler då dessa system tvingas uppfylla allt fler krav (billiga, effektiva, snabbt producerade, estetiska, miljövänliga etc.) kunna vara konkurrenskraftiga på marknaden. Av dessa skäl måste ingenjörer nu mer än någonsin beakta hela bilden av ett system eller delsystem för att kunna optimera det. I detta sammanhang syftar detta dokument till att presentera metoden och resultaten från optimeringen av trycksättningssystemet för en återanvändbar rakets första steg som heter Themis 3. Modelleringen av trycksättningssystemet har genomförts med hjälp av ett systemmodelleringsverktyg som kallas Geeglee. För att täcka in så många effekter av detta system som möjligt har en viktig del av raketsteget beaktats och modellerats (från trycksättningsgaserna till drivmedelstankarna, via tryck- och drivmedelsmatningsledningarna). Tre krav på hög nivå har identifierats som mycket viktiga för avvägningen vid utformningen av trycksättningssystem konstruktion: den totala masspåverkan, den totala icke-rekursiva kostnaden och den totala rekursiva kostnaden. Denna optimering har framför allt gjort det möjligt att bekräfta vissa välkända resultat, dvs. att exogena trycksättningssystem ger en mindre masspåverkan på fordonet, på bekostnad av en högre RC jämfört med autogena system.

This report delves into the early developmental phase of an autonomous vehicle designed for defense applications. Navigating diverse terrains, this unmanned ground vehicle (UGV) poses unique challenges, particularly in the absence of clearly defined directives found in typical traffic scenarios. The analysis employs the Systems-Theoretic Process Analysis (STPA) to identify and anticipate risks inherent in the conceptual stage of product development. Beyond the specific UGV case, the report explores the broader landscape of validating autonomous systems. It discusses prevalent methods, emphasizing adaptability to different contexts and stages of development. By shedding light on the risks and challenges of autonomy in vehicles and examining effective validation strategies, this report aims to contribute valuable insights to the ongoing discourse surrounding autonomous vehicle development.

abstract: The temperature of a planet's surface depends on numerous physical factors, including thermal inertia, albedo and the degree of insolation. Mars is a good target for thermal measurements because the low atmospheric pressure combined with the extreme dryness results in a surface dominated by large differences in thermal inertia, minimizing the effect of other physical properties. Since heat is propagated into the surface during the day and re-radiated at night, surface temperatures are affected by sub-surface properties down to several thermal skin depths. Because of this, orbital surface temperature measurements combined with a computational thermal model can be used to determine sub-surface structure. This technique has previously been applied to estimate the thickness and thermal inertia of soil layers on Mars on a regional scale, but the Mars Odyssey Thermal Emission Imaging System "THEMIS" instrument allows much higher-resolution thermal imagery to be obtained. Using archived THEMIS data and the KRC thermal model, a process has been developed for creating high-resolution maps of Martian soil layer thickness and thermal inertia, allowing investigation of the distribution of dust and sand at a scale of 100 m/pixel. / Dissertation/Thesis / M.S. Geological Sciences 2013

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第19508号 / 理博第4168号 / 新制||理||1599(附属図書館) / 32544 / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)教授 田口 聡, 教授 家森 俊彦, 教授 余田 成男 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

T cells are an essential part of the adaptive immune system and protect the body from intracellular infections. The specificity with which αßTCR-bearing T cells recognize cognate antigen presented on MHC molecules is paramount to maintaining the balance between mounting effector functions against pathogens and establishing peripheral tolerance to self. The mechanism by which T cells translate qualitative differences in TCR:pMHC binding to sensitive proximal signalling events which ultimately result in specific Tcell effector responses to infected cells but not to self is mostly unknown. To address how T cell signalling responds to qualitative differences in TCR triggering by pMHC, I established a system of stimulating T cells bearing the 1G4 TCR specifically in vitro with a panel of four NY-ESO-1_156-165 peptide variant MHC tetramers. Single amino acid substitutions to the NY-ESO-1_156-165 peptide conferred a maximum 35-fold difference in the monomeric affinity for the 1G4 TCR. The system allows the highly controlled investigation of very rapid TCR proximal signalling events simultaneously and quantitatively using flow cytometry. Stimulations with pMHC tetramers showed rapid sensitive sequential signalling responses which were able to confer ligand discrimination. Very early signalling events such as CD3ζ phosphorylation showed analogue responses to the different affinity pMHC tetramers. Later signalling events including phospho-ERK showed a distinct on/off switch-like response. The amplitude of the very early analogue signalling responses determined the extent of later digital ERK signals. This indicates that a certain analogue signalling threshold must be passed to result in T cell activation. The thymocyte protein Themis has been shown proximal TCR signalling to modulate thymocyte selection thresholds. Its deletion results in profound defects in positive thymocyte selection. Themis locates to the LAT signalosome of the TCR signalling cascade via Grb2, yet its molecular function is unknown. Employing the system I established, I demonstrate that Themis-k/d cells show increased levels of CD3z-chain phosphorylation, phospho-ERK signalling and signal-induced apoptosis which was independent of the ERK signal. This shows that Themis is a global attenuator of proximal TCR signalling. We are currently investigating possible associations of Themis to proteins phosphastases such as SHP-1 which could attenuate TCR proximal protein tyrosine signalling events.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20184号 / 理博第4269号 / 新制||理||1613(附属図書館) / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)教授 田口 聡, 教授 家森 俊彦, 教授 塩谷 雅人 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

Esta dissertação aborda um estudo de caso da experiência educacional realizada pela Organização não Governamental Themis, cuja missão é promover, defender e proteger os direitos humanos das mulheres. A pesquisa foi realizada com um grupo de mulheres cuja identidade racial abrange negras, brancas e indígena, residentes nos municípios de Canoas e Porto Alegre, no estado do Rio Grande do Sul. Todas são lideranças comunitárias que concluíram o curso de formação de Promotoras Legais Populares (PLPs), coordenado pela ONG Themis-Assessoria Jurídica e Estudos de Gênero. O período em estudo vai de 1996 a 2000, quando foi incluída a temática racial no programa do curso de formação das PLPs. Os fundamentos dessa pesquisa empírica/teórica estão no campo dos estudos sobre gênero, raça e educação popular, com ênfase no conceito de exclusão social. Trabalhei na perspectiva de compreender, a partir do ponto de vista das PLPs, se a inclusão da temática racial junto ao curso de formação de PLPs contribuiu ou não para a construção de suas identidades raciais e nas suas práticas sociais e políticas, como sujeitos multiplicadores de cidadania e defesa dos direitos das mulheres A experiência educacional é um recurso muito recorrente utilizado pelos movimentos sociais e pelas ONGs, como uma forma de suprir a ausência do Estado em responder pela construção plena da cidadania de todos brasileiros e brasileiras. Portanto, a pesquisa tem por referência um projeto pedagógico cujo objetivo é evidenciar o fenômeno do racismo, do patriarcalismo existente na sociedade brasileira, buscando resgatar ou reconstruir relações raciais, de gênero e classe social, baseadas no respeito às diferenças e no acesso universal dos direitos, bem como aos bens e serviços a todos e a todas / This study approaches a case study based on an educational experience conducted by an a non govemmental organization (NGO) called Themis, whose aim is to promote, defend and protect women's rights, recognizing the Judicial Power as the strategically privileged space for accomplishing a project aiming at women's social justice. This research was conducted with a group of women whose racial identities include black, white and indigenous women residing in Canoas and Porto Alegre, in the state of Rio Grande do Sul. They are ali community leaders, who have concluded the Popular Legal Prosecutors (PLPs) preparation course, which was coordinated by the Juridical and Gender Studies Support from Themis-NGO. The period studied began in 1996 until 2000, when the racial issue was included in the PLPs formation course. The fundaments of this theoretical/empirical research belong to the studies on gender, race and popular education, with emphasis on the concept of social exclusion. From this angle, social exclusion presents increasing obstacles towards the access of goods and social services resulting from the social production of wealth. The exclusion processes affect social groups in different ways, with higher or lower degree contact with exclusion, revealing itself to be extremely cruel, and the more extensive, the more the race, gender and social class overlap I have worked aiming at acquiring, from the PLPs point of view, a better understanding at whether the inclusion of the racial topic towards their formation, contributes or not to the construction of their racial identities and to their social and political practices, while being multipliers of citizenship and women's rights defense_ lt is important to highlight that this study refers to a five-year length experience. However, Themis - Juridical Assistance and Gender Studies - has been developing a pedagogical practice for ten years with popular groups at the county, state and national leveis_ The educational experience is a well used and recurrent resource being used by social movements and NGOs, as a way of supplying for the State's absence in assisting the complete citizenship construction of ali Brazilians. Therefore, this a pedagogical project aiming at making the phenomenon of racism, and the existing patronizing phenomenon in Brazilian society evident, and thus, rescuing or reconstructing racial, gender and social class relationships, based on respect to differences and on universal access to human rights, as well as goods and services to every one.