Dynamic Substructuring is a powerful tool for simplification of the analysis of complex structures and it has been well established along the years in analytical calculations by means of the Craig-Bampton technique. Recently, a new branch of substructuring, the Experimental Dynamic Substrucuring, appeared as a promising field of research for the engineering community. This area presents several intrinsic difficulties, evincing a need to develop the traditional substructuring methods towards obtaining better results using the experimental approach. In this scenery, the Transmission Simulator technique emerges as an instrument for potential improvement of the achieved results. This work represents a study on the use of the Transmission Simulator technique in the analysis of an Ampair A600 wind turbine blade subjected to loads at the interface to the hub, and it is a part of the benchmarking studies of SEM (Society of Experimental Mechanics). The work consisted of collecting experimental data via vibration tests of a single blade connected to different sizes of transmission simulators. After that, a mathematical representation of the blade was obtained via subtraction of the effect of the transmission simulators via substructuring technique. The computed model was subsequently coupled to a model of the remainder of the wind turbine (the hub plus two blades), and the results were compared to data acquired in tests of the whole assembly. The final findings did not reflect the theory prospects and further investigation is necessary to evaluate the effectiveness of the used methodology.

Research on multiple antenna systems has been a hot topic in recent years due to the demands for higher transmission rate and more reliable link in rich scattering environment in wireless communications. Using multiple antennas at both the transmitter side and the receiver side increases the channel capacity without additional frequency spectrum and transmitted power. However, due to the limited space at the size-limited terminal devices, the most critical problem in designing multiple antennas is the severe mutual coupling among them. The aim of this thesis is to provide compact, decoupled and efficient multiple antenna designs for terminal devices. At the same time, we propose a simple and cost effective method in multiple antenna measurement. All these efforts contribute to the development of terminal devices for the fourth generation wireless communication. The background and theory of multiple antenna systems are introduced first, in which three operating schemes of multiple antenna systems are discussed. Critical factors influencing the performance of multiple antenna systems are also analyzed in details. To design efficient multiple antenna systems in compact terminals, several decoupling methods, including defected ground plane, current localization, orthogonal polarization and decoupling networks, are proposed. The working mechanism and design procedure of each method are introduced, and their effectiveness is compared. Those methods can be applied to most of the terminal antennas, reducing the mutual coupling by at least 6dB. In some special cases, especially for low frequency bands below 1GHz, the chassis of the device itself radiates like an antenna, which complicates the antenna decoupling. Thus, we extend the general decoupling methods to the cases when the chassis is excited. Based on the characteristic mode analysis, three different solutions are provided, i.e., optimizing antenna locations, localizing antenna currents and creating orthogonal modes. These methods are applied to mobile phones, providing a more reliable link and a higher transmission rate, which are evaluated by diversity gain and channel capacity, respectively. In order to measure the performance of multiple antenna systems, it is necessary to obtain the correlation coefficients. However, the traditional measurement technique, which requires the phase and polarization information of the radiation patterns, is very expensive and time consuming. In this thesis, a more practical and convenient method is proposed. Fairly good accuracy is achieved when it is applied to various kinds of antennas. To design a compact and efficient multiple antenna system, besides the reduction of mutual coupling, the performance of each single antenna is also important. The techniques for antenna reconfiguration are demonstrated. Frequency and pattern reconfigurable antennas are constructed, providing more flexibility to multiple antenna systems. / QC 20120604

Interaction designers for mobile phones mainly focus on displays but have only little knowledge about sensor characteristics. Beside multitouch input, mobile devices provide versatile possibilities to interact in a physical, device-based manner due to their built-in hardware. Even though such interactions may provide many advantages in everyday life, they have limited visibility in interaction design. Interaction designers are seldom experts in gesture and pattern recognition and even prototypical implementations of simple mobile-based interactions need advanced technical knowledge. Hence, the potential for designing mobile device-based interactions is often not fully exploited. To contribute to a common knowledge of mobile device-based interactions, this paper proposes Mobile Spaces. This model aims at supporting designers of mobile applications to broaden their view on interaction possibilities with one or more collocated devices which go beyond the screen. We discuss the applicability of Mobile Spaces by means of several examples from research.

Beside traditional multitouch input, mobile devices provide various possibilities to interact in a physical, device-based manner due to their built-in hardware. Applying such interaction techniques allows for sharing content easily, e.g. by literally pouring content from one device into another, or accessing device functions quickly, e.g. by facing down the device to mute incoming calls. So-called mobile-based interaction techniques are characterized by movements and concrete positions in real spaces. Even though such interactions may provide many advantages in everyday life, they have limited visibility in interaction design due to the complexity of sensor processing. Hence, mobile-based interactions are often integrated, if any, at late design stages. To support testing interactive ideas in early design stages, we propose MilkyWay, a toolbox for prototyping collocated collaborative mobile-based interaction techniques. MilkyWay includes an API and a mobile application. It enables easily building up mobile interactive spaces between multiple collocated devices as well as prototyping interactions based on device sensors by a programming-by-demonstration approach. Appropriate sensors are selected and combined automatically to increase tool support. We demonstrate our approach using a proof of concept implementation of a collaborative Business Model Canvas (BMC) application.

In collocated collaboration, applied methods and technologies to support the collaboration process mainly comprise either analog paper and pen methods, large display applications or the usage of several laptops. Whereas paper and pen are easy to use, they impair the digital documentation and further editing. Large displays are expensive, stationary, and depend on speci_c environments. Furthermore, laptops build physical barriers between people, which impedes face-to-face communication. This leads to the fact that direct digitization is still not often performed in collocated collaborative scenarios, although it would be useful for further processing or permanent storing of created content.To address advantages of analog media, especially small size and high ubiquity, and eliminate the disadvantages, namely the lack of direct digitization, we aim at applying mobile devices to collocated collaboration. To contribute to the development of future collaboration tools, we derive and propose concrete design goals for applying mobile devices in collocated mixed-focus collaboration.

In mixed-focus collaboration, group members create content both individually as a kind of groundwork for discussion and further processing as well as directly together in group work sessions. In case of individual creation, separate documents and contents need to be merged to receive an overall solution. In our work, we focus on mixed-focus collaboration using mobile devices, especially smartphones, to create and merge content. Instead of using emails or messenger services to share content within a group, we describe three different mobile device-based interaction techniques for merging that use built-in sensors to enable ad-hoc collaboration and that are easy and eyes-free to perform. We conducted a user study to investigate these merging interactions. Overall, 21 participants tested the interactions and evaluated task load and User Experience (UX) of the proposed device-based interactions. Furthermore, they compared the interactions with a common way to share content, namely writing an email to send attached content. Participants gave valuable user feedback and stated that our merging interaction techniques were much easier to perform. Furthermore, we found that they were much faster, less demanding, and had a greater UX than email.

Esta dissertação de mestrado apresenta os resultados de uma investigação sobre os métodos de co-estimativa comumente utilizados em geoestatística. Estes métodos são: cokrigagem ordinária; cokrigagem colocalizada e krigagem com deriva externa. Além disso, a krigagem ordinária foi considerada apenas a título de ilustração como esse método trabalha quando a variável primária estiver pobremente amostrada. Como sabemos, os métodos de co-estimativa dependem de uma variável secundária amostrada sobre o domínio a ser estimado. Adicionalmente, esta variável deveria apresentar correlação linear com a variável principal ou variável primária. Geralmente, a variável primária é pobremente amostrada enquanto a variável secundária é conhecida sobre todo o domínio a ser estimado. Por exemplo, em exploração petrolífera, a variável primária é a porosidade medida em amostras de rocha retiradas de testemunhos e a variável secundária é a amplitude sísmica derivada de processamento de dados de reflexão sísmica. É importante mencionar que a variável primária e a variável secundária devem apresentar algum grau de correlação. Contudo, nós não sabemos como eles funcionam dependendo do grau de correlação. Esta é a questão. Assim, testamos os métodos de co-estimativa para vários conjuntos de dados apresentando diferentes graus de correlação. Na verdade, esses conjuntos de dados foram gerados em computador baseado em algoritmos de transformação de dados. Cinco valores de correlação foram considerados neste estudo: 0,993, 0,870, 0,752, 0,588 e 0,461. A cokrigagem colocalizada foi o melhor método entre todos testados. Este método tem um filtro interno que é aplicado no cálculo do peso da variável secundária, que por sua vez depende do coeficiente de correlação. De fato, quanto maior o coeficiente de correlação, maior é o peso da variável secundária. Então isso significa que este método funciona mesmo quando o coeficiente de correlação entre a variável primária e a variável secundária é baixo. Este é o resultado mais impressionante desta pesquisa. / This master dissertation presents the results of a survey into co-estimation methods commonly used in geostatistics. These methods are ordinary cokriging, collocated cokriging and kriging with an external drift. Besides that ordinary kriging was considered just to illustrate how it does work when the primary variable is poorly sampled. As we know co-estimation methods depend on a secondary variable sampled over the estimation domain. Moreover, this secondary variable should present linear correlation with the main variable or primary variable. Usually the primary variable is poorly sampled whereas the secondary variable is known over the estimation domain. For instance in oil exploration the primary variable is porosity as measured on rock samples gathered from drill holes and the secondary variable is seismic amplitude derived from processing seismic reflection data. It is important to mention that primary and secondary variables must present some degree of correlation. However, we do not know how they work depending on the correlation coefficient. That is the question. Thus, we have tested co-estimation methods for several data sets presenting different degrees of correlation. Actually, these data sets were generated in computer based on some data transform algorithms. Five correlation values have been considered in this study: 0.993; 0.870; 0.752; 0.588 and 0.461. Collocated simple cokriging was the best method among all tested. This method has an internal filter applied to compute the weight for the secondary variable, which in its turn depends on the correlation coefficient. In fact, the greater the correlation coefficient the greater the weight of secondary variable is. Then it means this method works even when the correlation coefficient between primary and secondary variables is low. This is the most impressive result that came out from this research.

Esta dissertação de mestrado apresenta os resultados de uma investigação sobre os métodos de co-estimativa comumente utilizados em geoestatística. Estes métodos são: cokrigagem ordinária; cokrigagem colocalizada e krigagem com deriva externa. Além disso, a krigagem ordinária foi considerada apenas a título de ilustração como esse método trabalha quando a variável primária estiver pobremente amostrada. Como sabemos, os métodos de co-estimativa dependem de uma variável secundária amostrada sobre o domínio a ser estimado. Adicionalmente, esta variável deveria apresentar correlação linear com a variável principal ou variável primária. Geralmente, a variável primária é pobremente amostrada enquanto a variável secundária é conhecida sobre todo o domínio a ser estimado. Por exemplo, em exploração petrolífera, a variável primária é a porosidade medida em amostras de rocha retiradas de testemunhos e a variável secundária é a amplitude sísmica derivada de processamento de dados de reflexão sísmica. É importante mencionar que a variável primária e a variável secundária devem apresentar algum grau de correlação. Contudo, nós não sabemos como eles funcionam dependendo do grau de correlação. Esta é a questão. Assim, testamos os métodos de co-estimativa para vários conjuntos de dados apresentando diferentes graus de correlação. Na verdade, esses conjuntos de dados foram gerados em computador baseado em algoritmos de transformação de dados. Cinco valores de correlação foram considerados neste estudo: 0,993, 0,870, 0,752, 0,588 e 0,461. A cokrigagem colocalizada foi o melhor método entre todos testados. Este método tem um filtro interno que é aplicado no cálculo do peso da variável secundária, que por sua vez depende do coeficiente de correlação. De fato, quanto maior o coeficiente de correlação, maior é o peso da variável secundária. Então isso significa que este método funciona mesmo quando o coeficiente de correlação entre a variável primária e a variável secundária é baixo. Este é o resultado mais impressionante desta pesquisa. / This master dissertation presents the results of a survey into co-estimation methods commonly used in geostatistics. These methods are ordinary cokriging, collocated cokriging and kriging with an external drift. Besides that ordinary kriging was considered just to illustrate how it does work when the primary variable is poorly sampled. As we know co-estimation methods depend on a secondary variable sampled over the estimation domain. Moreover, this secondary variable should present linear correlation with the main variable or primary variable. Usually the primary variable is poorly sampled whereas the secondary variable is known over the estimation domain. For instance in oil exploration the primary variable is porosity as measured on rock samples gathered from drill holes and the secondary variable is seismic amplitude derived from processing seismic reflection data. It is important to mention that primary and secondary variables must present some degree of correlation. However, we do not know how they work depending on the correlation coefficient. That is the question. Thus, we have tested co-estimation methods for several data sets presenting different degrees of correlation. Actually, these data sets were generated in computer based on some data transform algorithms. Five correlation values have been considered in this study: 0.993; 0.870; 0.752; 0.588 and 0.461. Collocated simple cokriging was the best method among all tested. This method has an internal filter applied to compute the weight for the secondary variable, which in its turn depends on the correlation coefficient. In fact, the greater the correlation coefficient the greater the weight of secondary variable is. Then it means this method works even when the correlation coefficient between primary and secondary variables is low. This is the most impressive result that came out from this research.

During discussions in collocated work it is necessary to vote for results or to rate them to reach an agreement and continue working. To ensure impartiality and to avoid social embarrassment, the assessment should then be performed anonymously in so far as other groups members should not see directly how a person votes or rates. With a growing number of digital devices in collaboration, this requirement also concerns such kinds of equipment. Our approach of ensuring anonymity of individual votes and ratings submitted on personal mobile phones is to avoid shoulder surfing activities. For this purpose, we designed four device-based interactions that aim at being easy to use and eyes-free to perform to stay in touch with the environment and potential shoulder surfers. We conducted a user study to investigate these interaction techniques and observed seven groups with four participants each while testing the interactions. Participants evaluated usability and User Experience (UX) aspects as well as unobtrusiveness of the four device-based interactions. Furthermore, participants gave valuable user feedback and stated that our proposed interactions help to avoid shoulder surfing.