With the increasing use of multimedia applications on the wireless network, the functionalities of the IEEE 802.11 WLAN was extended to allow traffic differentiation so that priority traffic gets quicker service time depending on their Quality of Service (QoS) requirements. The extended functionalities contained in the IEEE Medium Access Control (MAC) and Physical Layer (PHY) Specifications, i.e. the IEEE 802.11e specifications, are recommended values for channel access parameters along traffic lines and the channel access parameters are: the Minimum Contention Window CWmin, Maximum Contention Window CWmax, Arbitration inter-frame space number, (AIFSN) and the Transmission Opportunity (TXOP). These default Enhanced Distributed Channel Access (EDCA) contention values used by each traffic type in accessing the wireless medium are only recommended values which could be adjusted or changed based on the condition of number of associated nodes on the network. In particular, we focus on the Contention Window (CW) parameter and it has been shown that when the number of nodes on the network is small, a smaller value of CWmin should be used for channel access in order to avoid underutilization of channel time and when the number of associated nodes is large, a larger value of CWmin should be used in order to avoid large collisions and retransmissions on the network. Fortunately, allowance was made for these default values to be adjusted or changed but the challenge has been in designing an algorithm that constantly and automatically tunes the CWmin value so that the Access Point (AP) gives out the right CWmin value to be used on the WLAN and this value should be derived based on the level of activity experienced on the network or predefined QoS constraints while considering the dynamic nature of the WLAN. In this thesis, we propose the use of feedback based control and we design a controller for wireless medium access. The controller will give an output which will be the EDCA CWmin value to be used by contending stations/nodes in accessing the medium and this value will be based on current WLAN conditions. We propose the use of feedback control due to its established mathematical concepts particularly for single-input-single-output systems and multi-variable systems which are scenarios that apply to the WLAN.

A methodology was developed for isolation and transfer of 1-4 monolayer graphene from both Cu and Ni foil and Ni/SiO2/Si layered substrate types for use as electron transparent windows in environmental electron microscopy and spectroscopy. The graphene membranes were transferred onto disc "frames" made of stainless steel containing 3-10 μm diameter apertures. Such frames "windowed" with the graphene membrane are assembled into the custom designed environmental cell (e-cell) which contain a specimen immersed in the desired liquid or gaseous environment, and are compatible for imaging with a conventional scanning electron microscope (SEM) (in this case, a Hitachi 4500 SEM). Gold nanoparticles (50 nm) colloidal in water served as model specimens and were observed inside the e-cell using both secondary electron and backscattered electron detectors. An imaging induced radiolysis of water was observed at higher electron doses, which manifested itself in the formation of bubbles growing and coalescing under the enclosed graphene surface. Key SEM imaging parameters responsible for driving the radiolysis phenomena were addressed.

Amphibian populations are rapidly declining worldwide. Although individual factors may have large local influences, worldwide declines are attributed to interacting global stressors including rising temperatures and environmental pollutants. Globally, water temperatures closely track rising air temperatures and increase the metabolic rates of aquatic ectotherms, changing the rates of uptake, biotransformation, and excretion of contaminants, such as metals. To test how interactions of multiple, chronic stressors affect amphibian growth, I exposed Cope's gray treefrogs (Hyla chrysoscelis) in an outdoor mesocosm facility to three temperature regimes (ambient, ambient +1.5 oC, ambient +2.5 oC) in filtered lake water amended with mixtures of cadmium, copper, and lead ranging from 3.7 to 26.7 risk quotients (relative to the chronic concentration criteria protective of freshwater organisms). Temperature shifts and sublethal metals concentrations significantly affected the energetics of tadpoles as assessed by non-parametric and parametric analyses. Regression analyses indicated no significant relationship between temperature and time to forelimb emergence at the three lowest metals concentrations, but the relationship was parabolic at the three highest concentrations, indicating a differential effect of temperature across a gradient of water quality. The concept that tadpoles increase developmental rates to escape unfavorable aquatic conditions was supported at each temperature by shortened time to forelimb emergence (Gosner Stage 42) at the second highest metals concentration. This response, however, was overwhelmed by the energetic costs associated with the highest concentration and the highest temperature. Moreover, these parabolic relationships match predictions based on species specific thermal windows and pejus temperatures. My findings indicate that global warming may affect contaminated waters to a greater extent than pristine aquatic ecosystems, and that the primary effect may be diminished pejus and critical thermal maximum temperatures, and a narrowing of the species' thermal window.

Este trabalho teve o objetivo de mensurar o grau de satisfação dos clientes de uma loja de automóveis usados na serra gaúcha. O número de questionários coletados ao final da pesquisa foi de 146 entrevistados, possibilitando a criação de um perfil destes. O método utilizado foi de cunho exploratório, descritivo e explicativo. Para a coleta de dados, utilizou-se o um formulário baseado na escala Likert, que permitiu avaliar questões relativas à importância baseada no nível de concordância de uma afirmação. A partir das médias obtidas, aplicou-se uma série de ferramentas de análise. A principal delas foi a “Janela do Cliente”. A intenção foi descrever os principais atributos apontados a melhorar, sendo os principais e mais relevantes: flexibilidade na negociação, financiamento próprio, tempo de resposta, qualidade dos automóveis, promoções, taxa de juros, horário de atendimento, qualidade no atendimento, iluminação da loja, agilidade no atendimento, disposição dos carros e comprometimento. Também foi aplicada a ferramenta análise de variância (ANOVA), onde observamos a maioria dos atributos listados, com seus respectivos resultados. A análise de regressão serviu para apurar que 5 atributos foram eleitos como de maior relevância para os entrevistados, sendo a variável com maior impacto positivo sobre a satisfação geral dos clientes a flexibilidade na negociação. Por fim, com a análise fatorial foi possível criar grupos de variáveis que se relacionam, identificando 5 grupos de importância, classificados como: aparência estrutura e precificação, habilidade e negociação, disponibilidade da equipe, solicitude ao cliente e confiança. / This work had the objective of measuring the degree of customer satisfaction of a used car shop in the state of Rio Grande do Sul. The number of questionnaires collected at the end of the survey was 146 interviewees, making it possible to create a profile of these. The method used was exploratory, descriptive and explanatory. For data collection, a form based on the Likert scale was used, which allowed to evaluate questions related to the importance based on the level of agreement of an affirmation. From the averages obtained, a series of analysis tools were applied. The main one was the "Client Window". The intention was to describe the main attributes aimed at improving, being the main and most relevant: flexibility in negotiation, own financing, response time, car quality, promotions, interest rate, service hours, service quality, store lighting , Agility in service, car layout and commitment. We also applied the analysis of variance (ANOVA) tool, where we observed most of the listed attributes, with their respective results. The regression analysis served to ascertain that 5 attributes were chosen as of greater relevance for the interviewees, being the variable with the greatest positive impact on the general satisfaction of the clients the flexibility in the negotiation. Finally, with the factorial analysis it was possible to create groups of variables that are related, identifying 5 groups of importance, classified as: structure and pricing appearance, skill and negotiation, team availability, client solicitude and trust.

El tema de la presente investigación es “Elementos del Window Displays aplicados por tiendas de ropa y su influencia en la intención de compra en mujeres de 23 a 30 años del NSE B de la zona 7 de Lima Metropolitana”. La metodología de esta investigación es mixta de tipo correlacional, ya que se emplean datos cualitativos como cuantitativos y se busca asociar si existen relación o no ente dos variables (elementos del Window Displays e intención de compra). El principal objetivo de esta investigación es responder a la pregunta de investigación planteada que cuestiona si los elementos del Window Displays aplicadas por tiendas de ropa influyen en su intención de compra y comprobar la hipótesis propuesta, que señala que son tres los elementos (maniquíes, colores e iluminación). Es así que el objetivo general de investigación es indicar la influencia de dichos elementos. Para responder a dicho objetivo, como primer punto, se establecen los conceptos que intervienen en este estudio como visual externo, sus partes (rótulo, las entradas y las puertas y el Window Displays) y los tipos de compra de las personas. En la investigación cualitativa se recurrió a expertos en temas de Retail o Visual Merchandising y en la investigación cuantitativa a 129 personas pertenecientes al público objetivo con las que se realizó un análisis bivariado. Es así que se puede concluir que los elementos del Window Displays en mujeres de 23 a 30 años del NSC B de la zona 7 de Lima Metropolitana si influyen en su intención de compra. / The theme of the present investigation is "Elements of the Window Displays applied by clothing stores and their influence on the purchase intention in women from 23 to 30 years of NSE B of zone 7 of Metropolitan Lima". The methodology of this research is mixed correlational type, qualitative and quantitative are used in order to seeks if there is a relation or not between two variables (elements of the Window Displays and purchase intention). The main objective of this research is to answer the question of research raised whether the elements of the Window Displays applied by clothing stores influence their purchase intention and check the proposed hypothesis, which states that there are three elements (mannequins, colors and lighting). Thus, the general objective of research is to indicate the influence of these elements. To respond to this objective, as a first point, the concepts involved in this study as external visual, its parts (sign, entrances and doors and the Window Displays) and the types of people's purchases are established. In the qualitative research, experts in Retail or Visual Merchandising were consulted and in quantitative research, 129 people belonging to the target public were interviewed with a bivariate analysis. Thus, it can be concluded that the elements of the Window Displays in women from 23 to 30 years of the NSC B in zone 7 of Metropolitan Lima do influence their intention to purchase. / Trabajo de investigación

The resolution of spatial data has increased over the past decade making them more accurate in depicting landform features. From using a 60m resolution Landsat imagery to resolution close to a meter provided by data from Unmanned Aerial Systems, the number of pixels per area has increased drastically. Topographic features derived from high resolution remote sensing is relevant to measuring agricultural yield. However, conventional algorithms in Geographic Information Systems (GIS) used for processing digital elevation models (DEM) have severe limitations. Typically, 3-by-3 window sizes are used for evaluating the slope, aspect and curvature. Since this window size is very small compared to the resolution of the DEM, they are mostly resampled to a lower resolution to match the size of typical topographic features and decrease processing overheads. This results in low accuracy and limits the predictive ability of any model using such DEM data. In this dissertation, the landform attributes were derived over multiple scales using the concept of sliding window-based aggregation. Using aggregates from previous iteration increases the efficiency from linear to logarithmic thereby addressing scalability issues. The usefulness of DEM-derived topographic features within Random Forest models that predict agricultural yield was examined. The model utilized these derived topographic features and achieved the highest accuracy of 95.31% in predicting Normalized Difference Vegetation Index (NDVI) compared to a 51.89% for window size 3-by-3 in the conventional method. The efficacy of partial dependence plots (PDP) in terms of interpretability was also assessed. This aggregation methodology could serve as a suitable replacement for conventional landform evaluation techniques which mostly rely on reducing the DEM data to a lower resolution prior to data processing. / National Science Foundation (Award OIA-1355466)

A vertical-style data structure and operations on data in that structure are explored and tested in the domain of sliding window average algorithms for geographical information systems (GIS) data. The approach allows working with data of arbitrary precision, which is centrally important for very large GIS data sets. The novel data structure can be constructed from existing multi-channel image data, and data in the structure can be converted back to image data. While in the new structure, operations such as addition, division, and bit-level shifting can be performed in a parallelized manner. It is shown that the computation of averages for sliding windows on this data structure can be performed faster than using traditional computation techniques, and the approach scales to larger sliding window sizes.

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.

The apparent switch of the stated topic and name of the thesis from Art History to the actual name of the video Inside and Outside the Window became specifically meaningfull to me in that it reflects my own search for understanding, meaning and finding my own place in life and society. The term art history becomes one of many symbols of understanding and learning about a certain topic and it's value system. History of Art and it's evolution is first presented as a unified story, to be learned and accepted on face value as the only truth. But at a certain point it begins to unravel and fall apart and one is forced to doubt exactly those learned and accepted values. What was once accepted as observed or directly experienced is suddenly questioned not only through historical revaluation, but also personal introspection, rejection of absorbed values and a search for new and inherent personal values. But I myself am becoming a part of history and I am no longer the observer, but become the observed and I begin to realise that the newly discovered values are just a revised version of the old and learned ones.

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