No / The development of the IEEE 802.22 standard is aimed at providing broadband access in rural areas by effectively utilizing the unused TV band, provided no harmful interference is caused to the incumbent operation. The motivation behind TV band selection is of having lower frequencies compared to other licensed bands, which, therefore, results in lower propagation path loss. Due to this quality, the spectral power density of the radio signal reduces slowly, which results in a high coverage area. Further, it has been observed that many TV channels largely remain unoccupied, as most households and businesses rely on cable and satellite TV services. This is the first international standard for a wireless regional area network (WRAN) based on cognitive radio technologies. This standard provides both PHY and MAC layer functionalities in an infrastructure based network for communication between customer premise equipments (CPEs) through a base station (BS). The Spectrum Manager is the central part of the BS, which plays a significant role in maintaining spectrum availability information, channel selection, channel management, scheduling quiet periods for spectrum sensing, accessing to the database and implementing IEEE 802.22 policies. A WRAN can particularly accommodate up to 512 CPEs in a cell. Contention may occur during initial ranging, periodic ranging, bandwidth request and urgent coexistence situation notification. The medium access control (MAC) incorporates several schemes to control contention between CPEs within a cell and overlapping cells sharing the same channel. A CPE has to make decision to resolve collisions in the upstream direction. In the case of initial ranging and periodic ranging, code division multiple access (CDMA) is employed to resolve collisions. For bandwidth and UCS notification, either a CDMA or exponential time backoff approach can be applied for collision resolution. This paper presents the analytical framework to evaluate the number of active CPEs in a cognitive radio network, It is important to note that when the arrival rate becomes equal to the service rate, the active CPEs curve attains a constant value. Further, the active CPEs length is highly dependent on service rate. The different special cases have been addressed and the effectiveness of the proposed framework has been validated through various evaluation results.

Cognitive radio (CR) is seen as one of the enabling technologies for realizing a new regulatory spectrum management paradigm, viz. opportunistic spectrum sharing (OSS). In the OSS paradigm, unlicensed users (a.k.a. secondary users) opportunistically operate in fallow licensed spectrum on a non-interference basis to licensed users (a.k.a. incumbent or primary users). Incumbent users have absolute priority in licensed bands, and secondary users must vacate the channel where incumbent user signals are detected. A CR network is composed of secondary users equipped with CRs and it can coexist with incumbent users in licensed bands under the OSS paradigm. The coexistence between incumbent users and secondary users is referred to as incumbent coexistence, and the coexistence between CR networks of the same type is referred to as self-coexistence. In this dissertation, we address three coexistence-related problems at the medium access control (MAC) layer in CR networks: (1) the rendezvous (control channel) establishment problem, (2) the channel assignment problem in an ad hoc CR network, and (3) the spectrum sharing problem between infrastructure-based CR networks, i.e., the 802.22 wireless regional area networks (WRANs). Existing MAC layer protocols in conventional wireless networks fail to adequately address the key issues concerning incumbent and self coexistence that emerge in CR networks. To solve the rendezvous establishment problem, we present a systematic approach, based on quorum systems, for designing channel hopping protocols that ensure a pair of CRs to "rendezvous" within an upper-bounded time over a common channel that is free of incumbent user signals. In a single radio interface, ad hoc CR network, we propose a distributed channel assignment scheme that assigns channels at the granularity of "segments" for minimizing the channel switching overhead. By taking into account the coexistence requirements, we propose an inter-network spectrum sharing protocol that enables the sharing of vacant TV white space among coexisting WRANs. Our analytical and simulation results show that these proposed schemes can effectively address the aforementioned MAC layer coexistence problems in CR networks. / Ph. D.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal. / Cette étude porte sur l'un des épisodes les moins biens connus de l'histoire grecque hellénistique, le royaume de Bactriane (v. 245- v. 130 av. J.-C.). La Bactriane, ancienne satrapie perse d'Asie Centrale, entra dans le monde grec à la suite des conquêtes d'Alexandre le Grand et fit partie pendant plus d'un demi-siècle de l'empire séleucide, avant de s'en détacher dans des circonstances qui restent obscures. Les rois gréco-bactriens contrôlèrent durant plus d'un siècle la presque totalité de l' Asie Centrale, de même que le Nord-Ouest indien, avant de sombrer sous les assauts des peuples nomades de la steppe. Mais plus qu'une histoire politique, cette étude s'intéresse avant tout aux questions relatives à la cohabitation des Grecs et des barbares, et à ses conséquences sur la culture et les croyances des différents peuples qui habitaient le royaume. L'examen des sources littéraires, épigraphiques et numismatiques, ainsi que des données archéologiques nous permettra de constater que si la cohabitation de ces divers éléments du royaume fut pacifique, elle ne mena ni à la création d'un nouveau peuple, ni à l'hellénisation massive d'iraniens subjugués par la grandeur de la civilisation grecque. Qu'au contraire, Grecs et Iraniens, sujets tout autant à l'admiration réciproque qu'à la haine de l'autre, surent établir en Bactriane un modus vivendi qui leur permit de maintenir les privilèges des uns et des autres, la cohésion sociale et le mode de vie de chacun sans y apporter de grands changements. C'est donc de cette brève expérience, et en quelque sorte de l'échec de cette branche orientale de l'hellénisme, que traiteront les pages qui suivent.

En la actualidad, algunas regiones del Perú tienen muchas dificultades con respecto a la coexistencia pacífica, porque la mayoría de sujetos no obedecen ni respetan las normas, derechos y deberes que tiene la sociedad. En este contexto, se realizó una investigación con el objetivo de diseñar un programa Llasú basado en juegos cooperativos basado en reglas para desarrollar la convivencia democrática en niños de 4 años I.E.P. Rosita de Jesús -Chiclayo. Se utilizó el diseño no experimental, teniendo como muestra a 30 estudiantes, seleccionados mediante muestreo no probabilístico de tipo intencional, a quienes se le aplicó una lista de cotejo para medir el nivel de coexistencia pacífica en los niños. El instrumento fue adaptado por la investigadora, sometido a juicio de expertos obteniendo una validez de 0,91 y una confiabilidad de 0.878. Como resultado se obtuvo que el 63% de los estudiantes no desarrollan una buena coexistencia pacífica en las siguientes dimensiones: a) relaciona con cada sujeto b) elaboración de normas c) uso de disconformidad. Asimismo, se planteó una propuesta basada en un programa de juegos de reglas el cual consta de 12 sesiones, las cuales fueron validadas por profesionales expertos, quienes le otorgaron un puntaje de 98.1% de validez. Se concluye que el niño necesita de diferentes actividades lúdicas o recreativas basadas en juego de reglas con el fin de mejorar el nivel de coexistencia pacífica en los niños de la etapa pre escolar. / At present, some regions of Peru have many difficulties with respect to peaceful coexistence, because the majority of subjects do not obey or respect the norms, rights and duties that society has. In this context, an investigation was carried out with the objective of designing a Llasú program based on cooperative games based on rules to develop democratic coexistence in 4-year-old I.E.P. Rosita de Jesús -Chiclayo. The non-experimental design was used, taking as a sample 30 students, selected by intentional non-probabilistic sampling, to whom a checklist was applied to measure the level of peaceful coexistence in the children. The instrument was adapted by the researcher, subjected to expert judgment, obtaining a validity of 0.91 and a reliability of 0.878. As a result, it was obtained that 63% of the students do not develop a good peaceful coexistence in the following dimensions: a) relates to each subject b) elaboration of norms c) use of disagreement. Likewise, a proposal was made based on a game of rules program which consists of 12 sessions, which were validated by expert professionals, who gave it a score of 98.1% validity. It is concluded that the child needs different playful or recreational activities based on the game of rules in order to improve the level of peaceful coexistence in pre-school children.

En god sex- och samlevnadsundervisning i skolan är central för att ha möjlighet att utveckla en god hälsa, vilken dock enligt tidigare forskning har visats vara av bristande kvalitet. Syftet med studien är att undersöka högstadieelevers upplevelse av sex- och samlevnadsundervisningen på deras skola, med fokus på pedagog ledda lektioner. Studiens metod var en kvalitativ intervjustudie, där sex högstadieelever intervjuades individuellt. Resultatet visade att eleverna upplevde att undervisningens innehåll inte tillgodosåg deras behov fullt ut, då det lades för stort fokus på risker och faktabaserad kunskap. Det som eleverna ville veta mer om var sådant som kunde kopplas till samlevnad samt gjorde eleverna mer delaktiga i undervisningen, vilket de i stort upplevde att de inte var. Eleverna värdesatte undervisning som relaterade till deras vardag och verklighet. Internet framkom vara den främsta informationskällan för att skaffa kunskaper om sex och samlevnad och beskrevs som den källa som i första hand användes. Eleverna menade även att relationer var betydelsefullt i lärande om sex och samlevnad. Studiens slutsatser tryckte på att eleverna ska vara centrerade och i fokus i undervisningen, för att tillgodose deras behov av kunskaper samt delaktighet. Då internet visades vara den främsta kunskapskällan av sex och samlevnad, bör skolan använda sig av elevernas vana av internet i undervisningen. Det finns även anledning för skolan att ha relationer i åtanke, mellan såväl pedagoger och elever som eleverna i klassen. / A good sex-education in school is crucial for having the possibility to develop a good health, which though has been shown to be lacking in quality. The aim of the study is to examine high school students’ experiences of sex-education in their school with a focus on teacher led lectures. The study method was a qualitative interview study, where six high school students were interviewed individually. The result showed that the students experienced that the content of the sex-education did not meet their needs to the fullest, because there was too much focus on risks and fact-based knowledge. What the students wanted to know more about was topics related to coexistence and also made them more participant, which in generally they felt like they were not. The students valued education that related to their daily life and reality. Internet showed to be the primary source of information to get knowledge about sex and coexistence and was described as the firstly used source. The students also meant that relations with others was crucial when learning about sex and coexistence. Conclusions of the study pressures the students to be centered and the actual focus of the education, to meet their needs of knowledge and participation. Internet showed to be the primary used source of information of sex and coexistence content the school therefore should make use of it and integrate use of Internet in the education process. There are also reasons for the school to have relations in mind, between educators and students as well as students in classes.

The focus of this thesis is the numerical study of subcritical transition to turbulence in boundary-layer flows. For the most part, boundary layers with uniform suction are considered. Constant homogeneous suction counteracts the spatial growth of the boundary layer, rendering the flow parallel. This enables research approaches which are not feasible in the context of spatially developing flows. In the first part, the laminar–turbulent separatrix of the asymptotic suction boundary layer (ASBL) is investigated numerically by means of an edge-tracking algorithm. The obtained edge states experience recurrent dynamics, going through calm and bursting phases. The self-sustaining mechanism bears many similarities with the classical regeneration cycle of near-wall turbulence. The recurrent simple structure active during calm phases is compared to the nucleation of turbulence events in bypass transition originating from delocalised initial conditions. The implications on the understanding of the bypass-transition process and the edge state's role are discussed. Based on this understanding, a model is constructed which predicts the position of the nucleation of turbulent spots during free-stream turbulence induced transition in spatially developing boundary-layer flow. This model is used together with a probabilistic cellular automaton (PCA), which captures the spatial spreading of the spots, correctly reproducing the main statistical characteristics of the transition process. The last part of the thesis is concerned with the spatio-temporal aspects of turbulent ASBL in extended numerical domains near the onset of sustained turbulence. The different behaviour observed in ASBL, i.e. absence of sustained laminar–turbulent patterns, which have been reported in other wall-bounded flows, is associated with different character of the large-scale flow. In addition, an accurate quantitative estimate for the lowest Reynolds number with sustained turbulence is obtained / <p>QC 20160429</p>

The dissertation "History of newspaper publishing in Trutnov County between the second half of 19th century until 1938" is focused on the development of written journalism in Trutnov region since 1948 till the Munich Conference (29th - 30/9/1938). The thesis also reflects the period's wider theoretic and socio-historic context. Due to demographic characteristics of the region the dissertation also considers the issue of Czech-German coexistence and the changes in the mutual relationship among these nations in the border area. The dissertation also includes picture references taken from chosen newspapers. The reason for this is to give the reader a notion of the period regional newspapers.

Made available in DSpace on 2016-04-26T20:27:17Z (GMT). No. of bitstreams: 1 Jose Antonio Borges Pereira.pdf: 2355491 bytes, checksum: 0ed713529e8dd84e1e398eb2f28caff6 (MD5) Previous issue date: 2008-05-06 / The present work tries to show the importance of the children's and adolescents Family and Community Coexistence, which is considered, nowadays, one of the fundamental rights of this significant portion in the Brazilian population. This insertion in the child's and adolescents constitutional system was introduced with an independent micro system with its own principles causing the appearance of a new branch of the law, which intends to preserve the common and fundamental rights of any person and other special fundamental rights due to the fact that they are considered people under development. With this new view, the children and the adolescents are entitled of freedom of family and community coexistence with their natural family and only for serious reasons according to the law, the family power can be breached. In this case the substitutive family will always supply the lack of this fundamental right preserving to the maximum the closer relationship bonds through the guard, tutoring and also the adoption, that makes a new family without any differentiation of a natural family. This way the children's and adolescents institutionalization must be admitted in exceptional and precarious instance, not as the definitive solution for social accommodation, because it is the family, society and Estate s obligation to empower the family and social bows or, as a last resource, find substitutive families in order to avoid the orphanages. In this aspect it is important to have a law system for children and adolescents committed to solve the processes which are related to the family and community coexistence, mainly if they are institutionalized children and adolescents, because the longer the social and familiar isolation period is, the bigger are the psychosocial consequences / O presente trabalho buscou demonstrar a importância da Convivência Familiar e Comunitária das crianças e dos adolescentes, hoje considerado um dos direitos fundamentais desta parcela significativa para população brasileira. Esta inserção no sistema constitucional da criança e do adolescente eclodiu com um microssistema independente com princípios próprios trazendo o surgimento de um novo ramo do direito, que busca preservar os direitos fundamentais comuns de qualquer pessoa, outros direitos fundamentais especiais diante da condição de pessoas ainda em desenvolvimento. Com essa nova visão as crianças e os adolescentes têm o direito fundamental especial de liberdade da convivência familiar e comunitária no seio de sua família natural e somente por motivo gravíssimo previsto em lei poderá haver a quebra do vínculo do poder familiar, mas neste caso deverá sempre se buscar suprir a falta deste direito fundamental na família substituta preservando ao máximo os vínculos de parentesco mais próximos por meio da guarda, tutela e por fim a adoção que forma uma nova família sem qualquer diferenciação de uma família natural. Desta maneira a institucionalização de crianças e adolescentes deverá ser admitida em caráter excepcional e transitório, jamais como a solução definitiva de acomodação social, sendo dever da família, sociedade e Estado buscarem empoderar os laços familiares e sociais e em último caso buscarem famílias substitutas evitando o abrigamento. Neste aspecto é importante um sistema de justiça da infância e Juventude comprometida e ágil na solução de processos que esteja em questão à convivência familiar e comunitária, principalmente quanto se tratarem de crianças e adolescentes institucionalizadas, pois quando maior for o período de isolamento familiar e social, maior serão as seqüelas deixadas na sua formação psicossocial

The following essay aims to investigate Martin Heidegger’s notion of Dasein in Being and Time by taking into account the therein neglected existential-ontological aspect of birth. The point of departure is the concept of grundsein, i.e. Dasein being handed over itself as itself, groundlessly, with the remaining task of becoming its own basis from which it is able to properly project itself. In Being and Time this is made possible by actively grasping and appropriating ones ’ownmost possibility’ of being-towards-death. The present investigation however, raises the question whether or not Daseins other fundamental limit of being, namely birth, which in Being and Time is continuously disregarded, can provide a different understanding of grundsein; complementing the existing analysis by giving Dasein a more thorough framing. As for the proposed supplementing theory, the essay first turns to the concept of natality as it is developed in Hannah Arendt’s The Human Condition. Thereafter it traces the notion of birth as it unfolds in the work Relating Narratives by the contemporary Italian philosopher Adriana Cavarero, who thematically remains close to Arendt, although not without some crucial differences. With that in mind, the essay finally returns to Heidegger for a critical exploration of the theories opposed.  The present investigation aims to show that these theories of birth does in fact offer insights that are foreign to, albeit not irreconcilable with, the framework of Being and Time. Especially regarding that of mitsein, coexistence, which nonetheless also have inevitable consequences for the question of grundsein. By taking birth into consideration existentially, this essay seeks to shed light on what can be considered fundamentally relational aspects of Dasein as it is shown to be constitutively in-front-of, and a being-from-others. Furthermore there is shown to be an aspect of passive reception to Dasein, more specifically the non-negotiable gift of existence at all which unceasingly remains out of it’s reach; that is, arguably, somewhat overlooked in Being and Time (even though the concepts of thrownness and historicity may indicate such a condition). Lastly the author wishes to embed the existential-ontological matter of birth in the pressing planetary crisis of our time, asserting that the question of (human) birth and existence no longer can afford to ignore these biological-ecological aspects that are undeniably of due importance for the question at hand.

La forme du noyau est une caractéristique fondamentale de la matière nucléaire. Les isotopes légers pairs-pairs du krypton possèdent la surprenante propriété de présenter deux minimas pour leur énergie potentielle correspondants à deux déformations opposées. Alors que l'état fondamental 0+ peut avoir une déformation allongée ou aplatie, un second minimum aplati ou allongé respectivement, se dessine à une énergie inférieure à 1 MeV. Un tel phénomène est appelé coexistence de formes. Une première indication expérimentale est l'observation du second minimum correspondant à un état 0+ excité. Celui-ci a été observé tout au long de la chaîne du krypton. Un calcul de mélange des configurations allongée et aplatie met en évidence un changement de forme important de l'état fondamental en fonction du nombre de neutrons. Celui-ci serait de déformation allongée pour les 76,74Kr et deviendrait aplati pour le 72Kr. Une mesure directe de la déformation de ces noyaux est l'étape indispensable pour confirmer ces hypothèses. Une série d'expériences d'excitation Coulombienne auprès du dispositif SPIRAL associé au multi-détecteur EXOGAM au GANIL a été réalisée. Lors de ces expériences, la statistique était suffisante pour extraire les moments quadripolaires intrinsèques de ces noyaux grâce au code GOSIA. Ils établissent le caractère allongé de l'état fondamental et un état excité aplati conformément au scénario de coexistence de formes. Une mesure par « plunger » des temps de vie des états excités complète cette étude. Une expérience a été réalisée à haute énergie auprès du spectromètre LISE au GANIL permettant une première estimation de la collectivité du noyau de 68Se qui présenterait les mêmes propriétés. L'ensemble des résultats obtenus est comparé à des calculs théoriques de type HFB+Sly6+GCM.