Frame aggregation is one of the major MAC layer enhancements in the IEEE 802.11 family that boosts the network throughput performance. It aims to achieve higher throughput by transmitting huge amount of data in a single transmit oppor- tunity. With the increasing awareness of energy e ciency, it has become vital to rethink about the design of such frame aggregation protocol. Aggregation techniques help to reduce energy consumption over ideal channel conditions. However, in a noisy channel environment, a new energy-aware frame aggregation scheme is required. In this thesis, a novel Green Frame Aggregation (GFA) scheduling scheme has been proposed and evaluated. GFA optimizes the aggregate size based on channel quality in order to minimize the consumed energy. GFA selects the optimal sub-frame size that satisfies the loss constraint for real-time applications as well as the energy budget of the ideal channel situations. The design, the implementation, and evaluation of GFA using testbed deployment is done. The experimental analysis shows that GFA outperforms the conventional frame aggregation methodology in terms of energy e ciency by about 6⇥ in the presence of severe interference conditions. Moreover, GFA also outperforms the static frame sizing method in terms of network goodput and maintains almost the same end- to-end latency.

The present study focuses on developing a Frenet-Serret frame and the Apollonian Window. In the first part of the study Apollonian disks are generated for first four generations by developing visual basic codes in excel. For the second part of the study, three orthonormal basis vectors, namely, tangent, normal, and binormal vectors have been calculated for the tangent points of Apollonian discs for the first three generations. Equations of the Normal, Osculating and Rectifying planes and Taylor Series approximation have been calculated for specific theta. Because Apollonian Window consists of planar curves with constant curvature, torsion is nowhere present. The planar Frenet-Serret Equations for the first three generations for the Apollonian Window is also shown.

L’objectif de ce travail de thèse est d’enrichir la formulation du Lancer de Faisceaux Gaussiens (LFG) et de tester sa capacité à répondre à certains des besoins actuels en calculs de propagation dans le domaine du Radar terrestre. Le LFG est envisagé comme une alternative possible aux méthodes classiques (Equation Parabolique, méthodes de rayons) en environnement complexe urbanisé, en particulier en présence d’obstacles latéraux, avec une cible située en non visibilité. La méthode de LFG "de base", qui utilise des expressions analytiques obtenues par approximation paraxiale, permet des calculs de propagation rapides en environnements complexes, sans problèmes de caustiques. Elle conduit à des résultats de précision satisfaisante dans le domaine millimétrique, par exemple pour des calculs de champs intra-bâtiments. Aux fréquences plus basses comme celles utilisées en Radar terrestre, elle est limitée par une prise en compte trop approximative des effets de diffraction et par l’élargissement spatial des faisceaux gaussiens au regard des dimensions des obstacles. La théorie des frames est utilisée dans cette thèse pour dépasser ces limites. La théorie des frames fournit un cadre rigoureux pour la décomposition initiale du champ rayonné en faisceaux gaussiens, et permet de calibrer le nombre et les directions des faisceaux à lancer. Dans ce travail de thèse, l’emploi de frames de fenêtres gaussiennes pour décomposer des distributions de champs ou de sources équivalentes est généralisé aux distributions de champs incidents sur des plans ou des portions de plans, choisis en fonction des obstacles rencontrés et des distances parcourues. Les champs rayonnés à partir de ces plans sont alors obtenus par sommation des faisceaux gaussiens lancés depuis ces frames dits de "re-décomposition". Les transformations de faisceaux gaussiens par des obstacles de taille limitée sont ainsi traitées par redécomposition : les faisceaux incidents partiellement interceptés par des surfaces limitées sont "re-décomposés" successivement sur deux frames de re-décomposition, à fenêtres "étroites" puis "larges", définis dans les plans de ces surfaces. Le frame à fenêtres "étroites" permet de traiter les discontinuités physiques, tandis que le frame à fenêtres "larges" permet de propager les champs transformés sous la forme de faisceaux "collimatés". Dans cette thèse, nous présentons une formulation de ces re-décompositions permettant une mise en œuvre numériquement efficace, grâce à des expressions analytiques approchées des coefficients de frame pour la première décomposition, et des éléments de la matrice de changement de frame pour la seconde. Cette formulation est mise en œuvre numériquement, et l’influence de différents paramètres sur la précision des re-décompositions est analysée. Finalement, l’algorithme de LFG enrichi de ces re-décompositions successives est utilisé dans un scénario simplifié proche de situations rencontrées en propagation Radar terrestre. / In this work the Gaussian Beam Shooting (GBS) algorithm is complemented with new original formulations, and the ability of this "augmented" GBS algorithm to address specific problems encountered in electromagnetic field computations for ground-based Radar applications is tested. GBS is considered as an alternative to methods (Parabolic Equation, ray based methods) currently used for such computations in complex urban environments, especially when lateral obstacles and Non-Line-Of-Sight (NLOS) targets are involved. The "basic" GBS algorithm makes use of analytical expressions obtained through paraxial approximations. It allows to perform fast computations in complex environments, without suffering from any caustics problems. Reasonably accurate results have been obtained with this method in the millimetric range, e.g. for indoor field calculations. At lower frequencies, such as used in ground Radar systems, "basic" GBS cannot model diffraction effects accurately enough, and Gaussian beam width with respect to obstacle dimensions becomes a problem after some propagation distance. Frame theory is used in this PhD to overcome these limitations. Frame theory provides a rigorous framework for the initial decomposition of radiated fields into a set of Gaussian beams, providing flexible rules to adjust the number and directions of the launched beams. In this thesis, frame theory is used to discretize not only the source field distribution but also incident field distributions over planes or parts of planes of interest, according to encountered obstacles and propagation distances. The radiated fields are then obtained by summation of Gaussian beams launched from these frames called "reexpansion frames". Gaussian beam transformations by finite sized obstacles are addressed by this re-expansion scheme : the incident beams partially impinging on limited areas are successively "re-expanded" on two re-expansion frames, the first one composed of "narrow" windows and the second one of "wide" windows, both defined in the plane containing the limited area. Spatially narrow window frames allow to take into account abrupt transitions in space, and spatially wide window frames radiate in the form of collimated Gaussian beams. The re-expansion formulation proposed in this work is designed for efficient numerical implementation. Approximate analytical expressions are established for expansion coefficients on narrow window frames, and for frame change matrix elements. This formulation has been implemented, and the influence of frame parameters on re-expansion accuracy is analyzed. Finally, the GBS algorithm augmented with successive re-expansions is used to compute fields in simplified scenarios similar to situations encountered in ground-based Radar propagation problems.

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Thesis advisor: Elizabeth Rhodes / Historically, the narrative frame tale boasts a long and varied trajectory that originated in ancient India and includes texts such as the Panchatantra and the Arabian Nights. Eventually, many Eastern fables and the frame-tale structure that accompanied them entered the Western literary tradition through the cultural bridge that was medieval Spain. Considering the frame tale’s popularity in medieval texts, especially in fourteenth century Italian novella collections, it is curious to observe a decline in its use during the early-modern period in Europe. This study examines how the traditional framed novella collection dissolves into more fluid narrative forms. Novel, more structurally subtle types of framing devices, including the character-as-frame and the place-as-frame, maintain several consistent narratological functions with their historical counterparts. The frame tale’s form may have changed, but its function remains. The first chapter of this dissertation focuses on Boccaccio’s Decameron as the model for how a traditional frame tale functions. Four narratological framing functions – the aesthetic, the perspectivist, the metaleptic frame break, and the self-reflexive – work in concert to organize the text and engage readers in actively interpreting it. The remaining three chapters examine three exemplary moments in literary history when authors redesign and deploy the narrative frame: Lazarillo de Tormes, Part I of Don Quijote, and Cien años de soledad. These texts each create a paradigm shift by utilizing a well-known, well-established formal device in innovative ways. This dissertation argues that by understanding these works in a new light as framed texts, and by exposing the consistent functions at work within them, readers can better understand both the world of the text and the world outside it. / Thesis (PhD) — Boston College, 2018. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Romance Languages and Literatures.

When a structural element is acted upon by axial compressive force simultaneously with bending, the design must consider the effect of combined bending and compression. Hence, the structure should be designed with the consideration of bending moment in order to provide the enough design strength to the member. The main objective of this thesis is to compare the effect of interaction of flexural moment and axial compressive force on the regular column of the steel moment frame with the same column when cantilever section is introduced into the frame as the loading is kept constant in all three cases. In this work, STAAD is used to determine the required variables such as axial forces, bending moments and deformations in all the cases, and those values are used in approximate second order analysis for the further analysis of special steel moment frame. The calculated values are then plugged into the design interaction equation for combined flexure and compression as given by AISC Steel Construction Manual (2011) to check the criticality of the moment frame. The result of the analysis indicates that the regular frame model has higher demand of capacity ratio in design of columns than the one with cantilever projection.

Freud's theory of jokes explains how they overcome the mental "censors" that make it hard for us to think "forbidden" thoughts. But his theory did not work so well for humorous nonsense as for other comical subjects. In this essay I argue that the different forms of humor can be seen as much more similar, once we recognize the importance of knowledge about knowledge and, particularly, aspects of thinking concerned with recognizing and suppressing bugs ??neffective or destructive thought processes. When seen in this light, much humor that at first seems pointless, or mysterious, becomes more understandable.

Pilot Symbol Assisted Modulation (PSAM) is a good method to compensate for the channel fading effect in wireless mobile communications. In PSAM, known pilot symbols are periodically inserted into the transmitted data symbol stream and the receiver uses these symbols to derive amplitude and phase reference. <p> One aspect of this procedure, which has not received much attention yet, is the frame synchronization, i.e. the method used by the receiver to locate the time position of the pilot symbols. In this study, two novel non-coherent frame synchronization methods are introduced in which only the magnitude of received signal is used to obtain the timing of the pilot symbol. The methods are evaluated for both AWGN and frequency non-selective slow Rayleigh fading channels. <p> One synchronization technique is derived by standard maximum likelihood (ML) estimation formulation, and the other is obtained by using maximum a Posteriori probability (MAP) with a threshold test. Signal processing in the receiver uses simplifying approximations that rely on relatively high signal-to-noise ratio (SNR) as consistent with the reception of 16-QAM. Computer simulation has been used to test the acquisition time performance and the probability of false acquisition. Several lengths and patterns of pilot symbol sequences were tested where every 10th symbol was a pilot symbol and all other symbols were randomly selected data symbols. When compared with the other published synchronizers, results from this study show better performance in both AWGN and fading channels. Significantly better performance is observed in the presence of receiver frequency offsets.

Pilot Symbol Assisted Modulation (PSAM) is a good method to compensate for the channel fading effect in wireless mobile communications. In PSAM, known pilot symbols are periodically inserted into the transmitted data symbol stream and the receiver uses these symbols to derive amplitude and phase reference. <p> One aspect of this procedure, which has not received much attention yet, is the frame synchronization, i.e. the method used by the receiver to locate the time position of the pilot symbols. In this study, two novel non-coherent frame synchronization methods are introduced in which only the magnitude of received signal is used to obtain the timing of the pilot symbol. The methods are evaluated for both AWGN and frequency non-selective slow Rayleigh fading channels. <p> One synchronization technique is derived by standard maximum likelihood (ML) estimation formulation, and the other is obtained by using maximum a Posteriori probability (MAP) with a threshold test. Signal processing in the receiver uses simplifying approximations that rely on relatively high signal-to-noise ratio (SNR) as consistent with the reception of 16-QAM. Computer simulation has been used to test the acquisition time performance and the probability of false acquisition. Several lengths and patterns of pilot symbol sequences were tested where every 10th symbol was a pilot symbol and all other symbols were randomly selected data symbols. When compared with the other published synchronizers, results from this study show better performance in both AWGN and fading channels. Significantly better performance is observed in the presence of receiver frequency offsets.

­^¤åºK­n¡GInformation Technology (IT) as a competition advantage of the organization or individual has been widely welcome in the market. Orlikowski & Gash (1994) proposed the Theory of Technological Frame revealed that the organizational context affected the assumption and expectation of the technology. Furthermore, these assumption and expectation impacted the organization behavior. Thus, study the technological frame becomes a critical issue in understanding the IT development of the organization. We adopt the Theory of Technological Frame (Orlikowski & Gash, 1994) and make some reinforcement in the domain and category as the research model. This base guided us in understanding both the groups¡¦ and individual¡¦s behaviors of introduction and implementation of a groupware (Product Data Management, PDM) in the case study. In the data analyzing process, we employed the hermeneutic method to interpret and organize our finding. The research results indicated that the users hold positive perspective of PDM effectives in the following constructs¡G1. Reducing development time of new product¡F 2. Increasing the productivity of product design ¡F3. Increasing the accuracy of manufacturing and product design¡F4. Increasing and promoting the skill of working team¡F5. Assuring the data integrality and security¡F6. Building the data standard of aerospace. We believe that the consequence of research is useful for managers to understand the technological frame is important for enterprise¡¦s competitive capacity. Furthermore, understanding how to diagnosis, explanation and anticipation around information technology such change processes in organization. Keyword: information technology, Theory of Technological Frame