Energy-efficient Communication and Estimation in Wireless Sensor Networks

This thesis focuses on the energy efficiency in wireless networks under the transmission and information diffusion points of view. In particular, on one hand, the communication efficiency is investigated, attempting to reduce the consumption during transmissions, while on the other hand the energy efficiency of the procedures required to distribute the information among wireless nodes in complex networks is taken into account. For what concerns energy efficient communications, an innovative transmission scheme reusing source of opportunity signals is introduced. This kind of signals has never been previously studied in literature for communication purposes. The scope is to provide a way for transmitting information with energy consumption close to zero. On the theoretical side, starting from a general communication channel model subject to a limited input amplitude, the theme of low power transmission signals is tackled under the perspective of stating sufficient conditions for the capacity achieving input distribution to be discrete. Finally, the focus is shifted towards the design of energy efficient algorithms for the diffusion of information. In particular, the endeavours are aimed at solving an estimation problem distributed over a wireless sensor network. The proposed solutions are deeply analyzed both to ensure their energy efficiency and to guarantee their robustness against losses during the diffusion of information (against information diffusion truncation more in general).

Integration von Heizern in thermotrope flüssigkristalline Elastomer-Aktoren und deren Anwendung beim technischen Nachbau eines menschlichen Auges

Flüssigkristalline Elastomere (LCE) zeigen eine reversible Kontraktion und werden in der Literatur auch als „künstliche Muskeln“ bezeichnet. In dieser Arbeit werden sie mit einem integrierten Heizer versehen, um eine schnelle und präzise Ansteuerung zu ermöglichen. Anschließend werden diese als Aktoren zur Realisierung eines technischen Nachbaus des menschlichen Auges verwendet. rnDas einzigartige Verhalten der flüssigkristallinen Elastomere beruht auf der Kombination der Entropie Elastizität des Elastomers mit der Selbstorganisation der flüssigkristallinen Einheiten (Mesogene). Diese beiden Eigenschaften ermöglichen eine reversible, makroskopische Verformung beim Phasenübergang des Flüssigkristalls in die isotrope Phase. Hierbei ist es wichtig eine homogene Orientierung der Mesogene zu erzeugen, was in dieser Arbeit durch ein Magnetfeld erreicht wird. Da es sich um ein thermotropes flüssigkristallines Elastomer handelt, werden in dieser Arbeit zwei Ansätze vorgestellt, um den LCE intern zu heizen. Zum einen werden Kohlenstoffnanoröhren integriert, um diese über Strahlung oder Strom zu heizen und zum anderen wird ein flexibler Heizdraht integriert, welcher ebenfalls über Strom geheizt wird. rnUm den technischen Nachbau des menschlichen Auges zu realisieren, ist die Herstellung einer flüssigkristallinen Iris gezeigt. Hierzu wird ein radiales Magnetfeld aufgebaut, welches eine radiale Orientierung des Mesogene ermöglicht, wodurch wiederum eine radiale Kontraktion ermöglicht wird. Außerdem sind zwei Konzepte vorgestellt, um eine Elastomer Linse zu verformen. Zum einen wird diese mit einem ringförmigen LCE auseinandergezogen und somit abgeflacht. Zum anderen sind acht Aktoren über Anker an einer Linse angebracht, welche ebenfalls eine Vergrößerung der Linse bewirken. In beiden Fällen werden LCE mit dem zuvor präsentierten integrierten Heizdraht verwendet. Abschließend ist das Zusammensetzen des technische Nachbaus des menschlichen Auges dargestellt, sowie Aufnahmen, welche mit diesem erzeugt wurden.

"Dar voce a una voce": diversità e rappresentazione nella letteratura young adult. Proposta di traduzione di Gabi, a Girl in Pieces di Isabel Quintero.

In this dissertation, I will present my translation into Italian of several excerpts from Gabi, A Girl in Pieces, a young adult (YA) novel by Mexican-American author Isabel Quintero, along with examining the issues of diversity and representation in YA literature. This study aims to demonstrate the benefits of multicultural literature for young readers and the importance of publishing stories that reflect the diversity of the world we inhabit. The translation of the novel is accompanied by an analysis of its social, cultural, and literary context. The first chapter provides an overview of Chican@ history, literature, and culture, focusing on the concepts of identity and hybridity. The second chapter describes YA literature and its characteristics, outlines its history, and discusses the value of diverse books in the lives of teenage readers. Additionally, it cites relevant studies and statistics proving the dearth of diverse literature for young readers in the United States. The third chapter focuses specifically on the representation of Latin@s and Chican@s in literature for young readers, examining the main stereotypes that have plagued the depiction of this community and the new perspectives offered by Mexican-American YA authors. In the fourth chapter, I introduce Isabel Quintero and her novel Gabi, A Girl in Pieces, analyzing its plot, style, format, and main themes. In the fifth chapter, I provide my translation, which is then analyzed in the sixth and final chapter. The translation commentary details some of the problems I encountered and the strategies I applied. The sixth chapter also includes some observations on the translation of teenage speech, of multilingual texts, and of children’s and YA literature.

The Nightmare of Actual Identity": Franco-Algerian Literature after Liberation"

In this thesis I examine the issues of postcolonial Algerian identity expressed in literature, and the difficulty of defining an Algerian identity independent of French influence. I analyze and contextualize three novels (Le Polygone etoile by Kateb Yacine,L'Amour, la fantasia by Assia Djebar, and Le Village de l'allemand ou le journal des freres Schiller) representative of their respective periods. I explore the evolution of expressions of identity through post-liberation Algeria. The years immediately following decolonization are marked by the effort to return to aprecolonial blank slate, an effort that Yacine cautions against. The 1980s and 1990s are most concerned with re-inserting Algeria into the Western historical discourse, and the most recent literature moves beyond decolonization to discuss the current Islamistchallenge and immigration. Among the pertinent issues are language, oral vs. written traditions, the often blatant absence of Algerians and women from the accounts in the French colonial archives, and, of course, the Self/Other binary. I have found that theserepresentative authors and texts use asynchronic time, fragmented narrative, re-written history, and expressions of violence in an attempt to cope with the colonial period and decolonization. I show that these authors provide a commentary on those who have triedto erase their French side, but with little success. Ultimately, though in different ways, each author writes that Algerians much accept their French past and move beyond it,rather than fighting their collective history.

Modeling of red blood cell life-spans in hematologically normal populations

Despite the impact of red blood cell (RBC) Life-spans in some disease areas such as diabetes or anemia of chronic kidney disease, there is no consensus on how to quantitatively best describe the process. Several models have been proposed to explain the elimination process of RBCs: random destruction process, homogeneous life-span model, or a series of 4-transit compartment model. The aim of this work was to explore the different models that have been proposed in literature, and modifications to those. The impact of choosing the right model on future outcomes prediction--in the above mentioned areas--was also investigated. Both data from indirect (clinical data) and direct life-span measurement (biotin-labeled data) methods were analyzed using non-linear mixed effects models. Analysis showed that: (1) predictions from non-steady state data will depend on the RBC model chosen; (2) the transit compartment model, which considers variation in life-span in the RBC population, better describes RBC survival data than the random destruction or homogenous life-span models; and (3) the additional incorporation of random destruction patterns, although improving the description of the RBC survival data, does not appear to provide a marked improvement when describing clinical data.

Aporias of Trauma in Joyce's Ulysses and Faulkner's Light in August

In this thesis, I explore the relationships between trauma, memory, and narrative, particularly the ways in which trauma simultaneously disrupts and engenders narrative structures. I consider various trauma theories by authors such as Cathy Caruth, Judith Herman, Ruth Leys, and Dominick LaCapra. I also consider how psychoanalytic theory and criticism, specifically the writings of Sigmund Freud, inform the study of traumatic experience from both literary and personal perspectives. Furthermore, I consider theories regarding the relationship between trauma and narrative by authors such as Peter Brooks and John Pilkington. James Joyce¿s Ulysses and William Faulkner¿s Light in August serve, for my purposes, as trauma-texts and reflect the ways in which trauma might complicate the simultaneous destruction and creation of narrative strategies. Reading Ulysses and Light in August as trauma-texts that are both in mourning and melancholic gives us complementary, and contradictory, reasons for why we enjoy them. Mourning constructs a relationship between victim and witness, in which we can hear the voice of trauma and engage it in discourse. Conversely, melancholia creates a relationship between performer and spectator, in which we experience, and are fascinated by, the spectacle of another¿s trauma. Laughter, perversity, sorrow, and respite engage the reader in both texts, and raise questions about how one `remembers-to-forget¿ traumatic experiences. The narratives of each text¿s characters offer unique performances of mourning and melancholia. Thus, while this thesis engenders more questions than answers, I hope to argue that Ulysses and Light in August are significant literary works because each engages the reader in traumatic discourse, entertains the reader with the traumatic spectacle, and enlightens the reader on the complex relationship between trauma and narrative.

Interethnic Interaction Dynamics in the Russian Federation

The collapse of the Soviet Union at the beginning of the 1990s also meant the end of the idea of a common soviet identity incarnated in the "soviet man" and the new "historic community of the soviet people". While this idea still lives on in the generations of the 1920s to 1940s, the younger generations tend to prefer identification with family, profession, ethnic group or religion. Ms. Alexakhina set out to investigate different interethnic interaction strategies in the multi-ethnic context of the Russian Federation, with an emphasis on analysing the role of cultural and ethno-demographic characteristics of minority ethnic groups. It aimed to identify those specific patterns of interaction dynamics that have emerged in response to the political and economic transformation at present under way. The basic supposition was that the size and growth of an ethnic population are defined not only by demographic features such as fertility, mortality and net migration, but are also dependent on processes interethnic interaction and ethnic transition. The central hypothesis of the project was that the multi-ethnic and multi-cultural composition of Russia is apparently manifesting itself in the ethnic minority groups in various forms, but particularly in the form of ethnic revival and/or assimilation. The results of these complex phenomena are manifested as changes in ethnic attachments (national re-identification and language behaviour (multi-lingualism, language transition and loss of the mother tongue). The stress of the political and economic crisis has stimulated significant changes in ethnographic, social and cultural characteristics of inter-ethnic dynamics such as the rate of national re-identification, language behaviour, migration activity and the spread of mixed marriages, among both those minorities with a long history of settlement in Russia and those that were annexed during the soviet period. Patterns of language behaviour and the spread of mixed marriages were taken as the main indicators of the directions of interethnic interaction described as assimilation, ethnic revival and cultural pluralism. The first stage of the research involved a statistical analysis of census data from 1959 to 1994 in order to analyse the changing demographic composition of the largest ethnic groups of the Russian Federation. Until 1989 interethnic interaction in soviet society was distinguished by the process of russification but the political and economic transformation has stimulated the process of ethnic revival, leading to an apparent fall in the size of the Russian population due to ethnic re-identification by members of other ethnic groups who had previously identified themselves as Russian. Cross-classification of nationalities by demographic, social and cultural indicators has shown that the most important determinants of the nature of interethnic interaction are cultural factors such as religion and language affiliation. The analysis of the dynamics of language shift through the study of bilingualism and the domains of language usage for different demographic groups revealed a strong correlation between recognition of Russian as a mother tongue among some non-Russian ethnic groups and the declining size of these groups. The main conclusion from this macro-analysis of census data was the hypothesis of the growing importance of social and political factors upon ethnic succession, that ethnic identity is no longer a stable characteristic but has become dynamic in nature. In order to verify this hypothesis Ms. Alexakhina conducted a survey in four regions showing different patterns of interethnic interaction: the Karelian Republic, Buryatiya, the Nenezkii Autonomous Region and Tatarstan. These represented the west, east, north and south of the Russian Federation. Samples for the survey were prepared on the basis of census lists so as to exclude mono-Russian families in favour of mixed and ethnic-minority families. The survey confirmed the significant growth in the importance of ethnic affiliation in the everyday lives of people in the Federation following the de-centralisation of the political and economic spheres. Language was shown to be a key symbol of the consciousness of national distinction, confirmed by the fact that the process of russification has been reversed by the active mastering of the languages of titular nationalities. The results also confirmed that individual ethnic identity has ceased to be a fixed personal characteristic of one's cultural and genetic belonging, and people's social adaptation to the current political, social and economic conditions is also demonstrated in changes in individual ethnic self-identification. In general terms, the dynamic nature of national identity means that ethnic identity is at present acquiring the special features of overall social identity, for which the frequent change of priorities is an inherent feature of a person's life cycle. These are mainly linked with a multi-ethnic environment and high individual social mobility. From her results Ms. Alexakhina concludes that the development of national languages and multi-lingualism, together with the preservation of Russian as a state language, seems to be the most promising path to peaceful coexistence and the development of the national cultures of different ethnic groups within the Russian Federation.

Multiscale constitutive modeling of polymer materials

Materials are inherently multi-scale in nature consisting of distinct characteristics at various length scales from atoms to bulk material. There are no widely accepted predictive multi-scale modeling techniques that span from atomic level to bulk relating the effects of the structure at the nanometer (10-9 meter) on macro-scale properties. Traditional engineering deals with treating matter as continuous with no internal structure. In contrast to engineers, physicists have dealt with matter in its discrete structure at small length scales to understand fundamental behavior of materials. Multiscale modeling is of great scientific and technical importance as it can aid in designing novel materials that will enable us to tailor properties specific to an application like multi-functional materials. Polymer nanocomposite materials have the potential to provide significant increases in mechanical properties relative to current polymers used for structural applications. The nanoscale reinforcements have the potential to increase the effective interface between the reinforcement and the matrix by orders of magnitude for a given reinforcement volume fraction as relative to traditional micro- or macro-scale reinforcements. To facilitate the development of polymer nanocomposite materials, constitutive relationships must be established that predict the bulk mechanical properties of the materials as a function of the molecular structure. A computational hierarchical multiscale modeling technique is developed to study the bulk-level constitutive behavior of polymeric materials as a function of its molecular chemistry. Various parameters and modeling techniques from computational chemistry to continuum mechanics are utilized for the current modeling method. The cause and effect relationship of the parameters are studied to establish an efficient modeling framework. The proposed methodology is applied to three different polymers and validated using experimental data available in literature.

The Investigation of Different Variables in the Assaying of Silver Cyanide Solution

The assaying of gold and silver cyanide solutions is by no means new. The first method of analysis which is given in the literature is an evaporation method by S. B. Christy in 1896. However, the fire assaying of gold and silver dates further back than this. There is a method of fire assaying for gold and silver given in literature as early as 1556 in Georgius, Agricola’s De Re Metallica book.

Oil and Gas Production Methods in Montana

Montana's oil and gas industries aggregate a gross income of over 12,000,000 annually to the state. Oil and gas fields have been thoroughly discussed in liter­ature as to geology, location, production and future possibilities. The specific object of this report has been to compile a comprehensive study of the production methods as they occur.

The Determination of Aluminum in the Presence of Manganese and Iron by the Use of a Mercury Cathode

Since 1880, when Wolcott Gibbs made the suggestion that mercury could be used as a cathode in gravimetric electroanalysis, many articles have appeared in literature either criticizing the method or citing successful results which have been obtained by it.

An Isopach Map and a Discussion of the Permian in Wyoming and Adjacent Areas

The accelerated post-war demand for petroleum products with resultant high prices and dwindling reserves has spurred producers to an extensive search for new fields and for ad­ditional production in known fields. Exploration and discov­ery is dependent on the collection and correlation of vast amounts of data both in the field and that found in liter­ature.