Lunar constellations providing the capabilities of situational awareness and surveillance for future mission operators are analyzed in this study. The use of specialty orbits, such as sun-synchronous and frozen orbits, are analyzed to determine the applicability of these unique orbits. Additionally, altitude and inclination trades are performed to determine the degree to which mission objectives are achieved through ranges of these orbital parameters. Using the analyzed orbits, constellations of varying patterns are developed and surface coverage figures of merit are used to evaluate them. The research concludes with calculation of the yearly cross-track and in-track stationkeeping costs of a representative constellation. This stationkeeping is necessary for preservation of the designed coverage statistics.

The diploma paper addresses the topic of the relation between systemic constellations, social environment and social work. The objective of the paper was to ascertain for what reasons clients most often use this method of work. The questions we wished to be answered were for example how the respondents came across systemic constellations, how long their decision-making lasted, and what primary impulse was the most important one. It was also interesting to learn what experience they had with this method of work, what effect on their life they perceived and what benefit for themselves they saw in the method. The paper includes description of the course of their first experience with their own constellation which had been elaborated for them.

On étudie le problème de la transmission de l'information à travers le canal AWGN en utilisant des réseaux. On commence par considérer des constellations infinies. Une nouvelle famille de réseaux obtenus par Construction A à partir de codes linéaires non binaires est proposée. Ces réseaux sont appelés LDA ("Low-Density Construction A") et sont caractérisés par des matrices de parité p-aires creuses, qui les mettent en relation directe avec les codes LPDC. Deux résultats sur leur possibilité d'atteindre la capacité de Poltyrev sont provés ; cela est d'abord démontré pour des poids des lignes logarithmiques des matrices de parité associées, puis pour des poids constants. Le deuxième résultat est basé sur certaines propriétés d'expansion des graphes de Tanner correspondants à ces matrices. Un autre sujet de ce travail concerne les constellations finies de réseaux. une nouvelle preuve est donnée du fait que des réseaux aléatoires obtenus par Construction A generale atteignent la capacité avec décodage de type "lattice decoding". Cela prolonge et améliore le travail de Erez et Zamir (2004), Ordentlich et Edrez (2012) Ling et Belfiore (2013). Cette preuve est basée sur les constellations de Coronoï et la multiplication par le coefficient de Wiener ("MMSE scaling") du siganl en sortie du canal. Finalement, ce résultat est adapté au cas des réseaux LDA, qui eux aussi atteignent la capacité avec le même procédé de transmission. Encore une fois, il est nécessaire d'exploiter les propriétés d'expansion des graphes de Tanner. A la fin de la dissertation, on présente un algorithme de décodage itératif et de type "message-passing" approprié au décodage des LDA en grandes dimensions. / The probleme of transmission of information over the AWGN channel using lattices is addressed. Firstly, infinite constellations are considered. A nex family of integer lattices built by means of construction A with non-binary linear condes is introduced. These lattices are called LPA (Low-Density Construction A) and are characterised by sparse p-ary parity-chedk matrices, that put them in direct relation with LPDC codes. Two results about the Poltyrev-capacity-archieving qualities of this family are proved, respectively for logarithmic row degree and constant row degree of the associated parity-check matrices. The second result is based on some expansion poperties of the Tanner graphs related to these matrices. Another topic of this work concerns finite lattice constellations. A new proff that heneral random Construction A lattices achieve capacity under lattice deconding is provided, continuing and pimproving the work of Erez and Zamir (2004), Ordentlich an Erez (2012), and Ling and Belfiore (2013). This proof is based on Voronoi lattice constellations and MMSE scaling of the channel output. Finally, this approach is adapted to the LDA case abd ut us scgiwn tgat LDA lattices achive capacity with the ame transmission scheme, too. Once again, it is necessary to exploit the expansion properties of the Tanner graphs. At he end of the dissertation, an iterative message-passing algorithm suitable for decoding LDA lattices in high dimensions is presented.

As near-Earth space becomes increasingly crowded with spacecraft and debris, the need for improved space situational awareness has become paramount. Contemporary ground-based systems are limited in the detection of very small or dim targets. In contrast, space-based systems, above most atmospheric interference, can achieve significant improvements in dim target detection by observing targets against a clutter-free space background, i.e. targets above the horizon (ATH). In this study, numerical methods for the evaluation of ATH coverage provided by constellations of satellites are developed. Analysis of ATH coverage volume is reduced to a planar analysis of cross-sectional coverage area in the orbit plane. The coverage model performs sequences of boolean operations between polygons representing cross-sections of satellite sensor coverage regions and regions of interest, returning the coverage area at the desired multiplicity. This methodology allows investigation of any coverage multiplicity for planar constellations of any size, and use of arbitrary sensor profiles and regions of interest. The implementation is applied to several constellation design problems demonstrating the utility of the numerical ATH coverage model in a constellation design process. / text

Literature suggests that consumers perceive collective symbolic meaning in a set of products and brands and they associate this meaning with social roles or lifestyles that form consumption constellations. Such constellations exist as cognitive associative frameworks in consumers’ minds, which possess varying levels of accessibility. This thesis uses a multi-method approach to investigate how consumer perception and accessibility of consumption constellations is shaped by the psychosocial development that occurs during the transitional period of emerging adulthood. More specifically, two studies examine the role of the key drivers of psychosocial development at this stage: ego identity exploration and commitment. Study 1 employs a long interview methodology to provide insight into the dynamic nature of identity development during the period of emerging adulthood and its influence on perceptions of social roles and associated products and brands that comprise consumption constellations. Study 2 uses a response latency methodology to examine how emerging adults’ accessibility of consumption constellations is impacted by identity exploration and commitment, with hypotheses being partially supported. For aspirational constellations, high identity commitment participants displayed greater accessibility, with no significant differences based upon identity exploration as hypothesized.

In wireless channels and many other channels, interference is a central phenomenon. Mitigating interference is a key to improving system performance. To find the limit of the achievable rates for these channels in the presence of interference, the two-user Gaussian interference channel has been the subject of intensive study in network information theory. However, most current results have been obtained by assuming Gaussian input distributions. While optimal in single-user Gaussian channels, the issue with this assumption is that the Gaussian noise becomes the worst noise when the input distribution is also Gaussian. In this thesis, we propose a class of discrete constellations. We show that this class of constellations can automatically achieve the same sum rates as schemes that treat interference as noise or perform time sharing.

In wireless channels and many other channels, interference is a central phenomenon. Mitigating interference is a key to improving system performance. To find the limit of the achievable rates for these channels in the presence of interference, the two-user Gaussian interference channel has been the subject of intensive study in network information theory. However, most current results have been obtained by assuming Gaussian input distributions. While optimal in single-user Gaussian channels, the issue with this assumption is that the Gaussian noise becomes the worst noise when the input distribution is also Gaussian. In this thesis, we propose a class of discrete constellations. We show that this class of constellations can automatically achieve the same sum rates as schemes that treat interference as noise or perform time sharing.

Substantial research has examined how linguistic structures are realized in the visual/spatial modality. However, we know less about linguistic pragmatics in signed languages, particularly the functioning of referring expressions (REs). Recent research has explored how REs are deployed in signed languages, but much remains to be learned. Study 1 explores the inventory and workings of REs in American Sign Language by seeking to replicate and build upon Frederiksen & Mayberry (2016). Following Ariel, F&M propose an inventory of REs in ASL ranked according to the typical accessibility of the referents each RE type signals. Study 1 reproduced their results using more complex narratives and including a wider range of REs in various syntactic roles. Using Toole’s (1997) accessibility rating protocol, we calculated average accessibility ratings for each RE type, thus making possible statistical analyses that show more precisely which REs differ significantly in average accessibility. Further, several RE types that F&M had collapsed are shown to be distinct. Finally, we find general similarities between allocations of REs in ASL and in spoken English, based on 6 matched narratives produced by native English speakers. Study 2 explores a previously unexamined set of questions about concurrently occurring REs: collections of REs produced simultaneously. It compares isolated REs that occur in a linear fashion, similar to spoken language grammars, with co-occurring REs, signaling multiple referents simultaneously (termed here constellations). This study asks whether REs in constellations have pragmatic properties different from those of isolated/linear REs. Statistical evidence is presented that some categories of REs do differ significantly in the average accessibility values of their referents, when compared across linear versus concurrent configurations. Study 3 examines whether the proportions of various RE categories used by native ASL signers vary according to the recipient’s familiarity with the narrative. Do ASL narratives designed to be maximally explicit because of low recipient familiarity demonstrate distinct RE allocations? In this sample of 34 narratives, there is no statistically significant difference in RE use attributable to recipient familiarity. These findings have important implications for understanding the impact of modality on accessibility, the use of REs in ASL, and visual processing.

We comprehensively examined the rare variants in the IPO11-HTR1A region to explore their roles in neuropsychiatric disorders. Five hundred seventy-three to 1,181 rare SNPs in subjects of European descent and 1,234-2,529 SNPs in subjects of African descent (0

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