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Approved for public release; distribution in unlimited. / The relational database model has become the most popular and widespread database model. Most current database systems are based upon or related to -he relational model. However, the relational model is beset with significant limitations, pitfalls and deficiencies. The relational model can be substantially improved with graphical interfaces. To this end, the Graphics Language for Accessing Database (GLAD) can provide easy to use and learn graphics interfaces for the relational model. Data structures and algorithms for GLAD will be presented to extend the relational model. / http://archive.org/details/datastructuresal00gren / Captain, United States Marine Corps

M.Com. (Informatics) / In this study the issue on User Interface Management Systems (UIMSs) is addressed. Specific attention is given to the design principles regarding development of user interface management systems that allow the creation of graphical user interfaces for existing text-oriented command-line applications. As an introduction the concept of user interface management systems is discussed and a working and formal definition is derived. Thereafter a survey is discussed concerning user interface tools. A user interface management system architecture is proposed; \he planning, design and development aspects of user interface management systems are addressed, and the effect of human factors in the design of a user interface management system is discussed. Attention is also given to various interaction and dialogue models ...

Notre recherche concerne les nouvelles approches qui améliorent l’exploration 3D dans des environnements virtuels pour les utilisateurs. De ce fait, nous nous focalisons sur la conception de nouvelles techniques d’interaction 3D transversales, qui sont simples, efficaces et bénéficient de la nouvelle périphérique d’entrée, comme les interfaces tactiles. Notre approche permet aux utilisateurs d’effectuer une interaction 3D complexes à l’aide d’entrée touche simple et multiples. Les utilisateurs effectuer des gestes en utilisent des touches simple et des esquisses pour interagir avec le contenu. Pour faire des conclusions sur la facilité d’utilisation de nos interfaces nous évaluons les techniques d’interaction en menant des études utilisateurs. Ensuite, nous adoptons des techniques traditionnelles et d’illustration de visualisation pour mettre en avant des caractéristiques différentes de l’objet en cible tout en préservant les informations de contexte. En outre, nous proposons de nouvelles méthodes de collaboration entre les utilisateurs qui interagissent avec les données 3D en utilisant la technologie divers, comme des périphériques mobiles de petite taille et des environnements virtuels immersifs. / Our research concerns the investigation of new approaches that enhance 3D exploration in virtual environments for users. Thereby, we concentrate on design of novel transversal 3D interaction techniques that are simple, efficient and benefit from new input technology, like tactile interfaces. Our approach allows users to perform complex 3D interaction using single and multiple 2D touch input. Users carry out simple touch, stroke or sketch-based gestures to interact with content. To draw conclusions about the usability of our interfaces we evaluate the interaction techniques by conducting users studies. In addition, we adopt different traditional and illustrative visualization techniques to highlight object characteristics in focus while preserving context information. Furthermore, we propose new methods for collaboration between users, who interact together with 3D data using varying technology, from small mobile devices to immersive virtual environments.

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, in ful llment of the requirements for the degree of Master of Science. October 31, 2016. / Brain Computer Interface (BCI) technology is a promising new channel for communication between humans and computers, and consequently other humans. This technology has the potential to form the basis for a paradigm shift in communication for people with disabilities or neuro-degenerative ailments. The objective of this work is to create an asynchronous BCI that is based on a commercial-grade electroencephalography (EEG) sensor. The BCI is intended to allow a user of possibly low income means to issue control signals to a computer by using modulated cortical activation patterns as a control signal. The user achieves this modulation by performing a mental task such as imagining waving the left arm until the computer performs the action intended by the user. In our work, we make use of the Emotiv EPOC headset to perform the EEG measurements. We validate our models by assessing their performance when the experimental data is collected using clinical-grade EEG technology. We make use of a publicly available data-set in the validation phase. We apply signal processing concepts to extract the power spectrum of each electrode from the EEG time-series data. In particular, we make use of the fast Fourier transform (FFT). Specific bands in the power spectra are used to construct a vector that represents an abstract state the brain is in at that particular moment. The selected bands are motivated by insights from neuroscience. The state vector is used in conjunction with a model that performs classification. The exact purpose of the model is to associate the input data with an abstract classification result which can then used to select the appropriate set of instructions to be executed by the computer. In our work, we make use of probabilistic graphical models to perform this association. The performance of two probabilistic graphical models is evaluated in this work. As a preliminary step, we perform classification on pre-segmented data and we assess the performance of the hidden conditional random fields (HCRF) model. The pre-segmented data has a trial structure such that each data le contains the power spectra measurements associated with only one mental task. The objective of the assessment is to determine how well the HCRF models the spatio-spectral and temporal relationships in the EEG data when mental tasks are performed in the aforementioned manner. In other words, the HCRF is to model the internal dynamics of the data corresponding to the mental task. The performance of the HCRF is assessed over three and four classes. We find that the HCRF can model the internal structure of the data corresponding to different mental tasks. As the final step, we perform classification on continuous data that is not segmented and assess the performance of the latent dynamic conditional random fields (LDCRF). The LDCRF is used to perform sequence segmentation and labeling at each time-step so as to allow the program to determine which action should be taken at that moment. The sequence segmentation and labeling is the primary capability that we require in order to facilitate an asynchronous BCI protocol. The continuous data has a trial structure such that each data le contains the power spectra measurements associated with three different mental tasks. The mental tasks are randomly selected at 15 second intervals. The objective of the assessment is to determine how well the LDCRF models the spatio-spectral and temporal relationships in the EEG data, both within each mental task and in the transitions between mental tasks. The performance of the LDCRF is assessed over three classes for both the publicly available data and the data we obtained using the Emotiv EPOC headset. We find that the LDCRF produces a true positive classification rate of 82.31% averaged over three subjects, on the validation data which is in the publicly available data. On the data collected using the Emotiv EPOC, we find that the LDCRF produces a true positive classification rate of 42.55% averaged over two subjects. In the two assessments involving the LDCRF, the random classification strategy would produce a true positive classification rate of 33.34%. It is thus clear that our classification strategy provides above random performance on the two groups of data-sets. We conclude that our results indicate that creating low-cost EEG based BCI technology holds potential for future development. However, as discussed in the final chapter, further work on both the software and low-cost hardware aspects is required in order to improve the performance of the technology as it relates to the low-cost context. / LG2017

El trabajo desarrollado en la presente tesis consiste en el diseño e implementación de un emulador de redes de alta capacidad, como entorno de pruebas de nuevas tecnologías previo su despliegue. El emulador está conformado por módulos implementados usando el lenguaje de programación Python. A largo plazo, se desea integrar el presente emulador en un rack de alta capacidad (con enlaces de 10 Gbps), el cual se encuentra en el laboratorio del Grupo de Investigación en Redes Avanzadas (GIRA) de la Pontificia Universidad Católica del Perú. En dicho rack, se ha instalado el software de Cloud Computing OpenStack, el cual emplea diferentes servicios para la creación de las máquinas virtuales a usar en el emulador. El objetivo principal del emulador es que las pruebas realizadas en él presenten una alta fidelidad: no solo se desea capturar el comportamiento de la red al limitar la tasa de bits o introducir latencia en un enlace, sino también evitar generar fenómenos espurios –como pérdida de paquetes– debido a las limitaciones de procesamiento del hardware sobre el cual funciona el emulador. Por ello, el emulador incluye un proceso de calibración del hardware subyacente, así como un módulo de validación de recursos (p.ej. RAM, cores, etc.) para asegurar que el emulador puede soportar la topología de interés. En el primer capítulo, se describe la situación actual de las redes —específicamente la de los proveedores de servicios— y se identifican los problemas que surgen con la evolución y desarrollo de nuevos servicios. Asimismo, se presentan algunas tecnologías emergentes como posibles soluciones a los problemas mencionados. En el segundo capítulo, se presentan los tipos de entornos de prueba que se utilizan para evaluar distintos prototipos de redes; en especial, los que proponen las tecnologías emergentes. Adicionalmente, se realiza un análisis de las ventajas y desventajas de cada entorno y se determina cuál es más conveniente para los objetivos del presente trabajo. En la última parte del capítulo, se presentan los objetivos del trabajo de tesis, en base a la problemática y al entorno de prueba determinado. El tercer capítulo está orientado a las tecnologías de virtualización. Primero, se introduce el concepto de virtualización y se presenta el modelo de Cloud Computing. Luego, se desarrollan las áreas de virtualización, mostrando las diversas técnicas existentes en cada una y la necesidad de monitorear el estado de la infraestructura. Por último, se realiza una descripción de OpenStack, dado que es el software empleado en el presente trabajo de tesis. En el cuarto capítulo, se detalla el diseño completo del emulador. Se inicia con las consideraciones y requerimientos del emulador; a continuación, se presenta la arquitectura del emulador, indicando sus módulos y el funcionamiento de cada uno; luego, se detallan los cambios realizados a OpenStack, seguido del módulo de validación del emulador –que lo diferencia de los demás existentes; finalmente, se muestra la interfaz de usuario para la creación de los experimentos. En el capítulo final, se presentan los resultados obtenidos al realizar pruebas en el emulador. Estas pruebas tienen la finalidad de demostrar que el emulador funciona en base a los objetivos y requerimientos planteados. También se muestra el análisis realizado en la etapa de calibración, en donde se obtiene la cantidad de recursos requeridos por cada nodo. Por último, se presentan las conclusiones obtenidas de la implementación y de las pruebas desarrolladas, basadas en los objetivos de la tesis y los requerimientos del emulador, así como las recomendaciones sugeridas para un mejor desempeño del mismo. / Tesis

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目前，膠體粒子在眾多領域扮演著越來重要的角色，例如工業中油漆流變特性的修飾以及在醫藥靶向藥物釋放等。通過改變膠體粒子間的相互作用 ，可以設計得到適合不同需要的穩定的流體、凝膠和晶體 。而開拓膠體粒子廣泛用途的 前提是對於膠體粒子穩定性的充分理解， 因此，對溶液中粒子間的相互作用的研究很有必要 。 / 本文主要討論了兩個問題 ，均圍繞如何利用小體積膠粒子改變大體積粒子間相互作用 。第一部分 ，我們研究二元粒子懸浮液中膠體粒間的相互作用。結果顯示，帶電納米粒子的加入可以改變帶電納米粒子與平面間的相互作用。當以上三者均輕微帶電，即使在很低的濃度下， 納米粒子也會發生沉積，並導致表面間靜電排斥作用的增強 。而對於高度帶電的納米粒子， 微米粒子和平面 ，納米粒子的吸附將受到阻礙，但實驗結果顯示，此時納米粒子仍能夠引導微與平引導微與平面間的額外斥力。此現象違反傳統高電系統中小體積粒子通常引導排空引力的認知。我們認為此現象可能來源於納米粒子被困於平面附近的區域時引導的排斥力 。 在相互排斥的微米粒子及納體系中 ，這個結果是對納米光暈增強的第一個研究 ，並對利用帶電納米粒子調節二元體系穩定性的傳統方法提出挑戰。 / 在本文的第二部分，我們將對二元帶電粒子相互作用的研究擴展到流體介面。 我們系統研究了二元膠體粒子分別在油水介面和空氣上的相互作用。我們利用高分辨亮場顯微鏡和粒子追蹤方法對受限膠體粒子間的相互作用進行研究。結果顯示 ，偶極 -偶極排斥作用在油水介面和空氣上的行為一致。介面膠體粒子間的相互作用主要包括兩個方面，一是對水相電解質敏感的偶極-偶極排斥作用，二是油相中殘餘電荷的靜電排斥作用 。另外，我們的結果顯示在介面上小體積粒子的加入可以導致二維排空引力，使得大體積粒子相互靠近。與溶液中不同的是，這個二維排空引力能夠在很低濃度時發生。 相信這個結果可以鼓勵更多理論方面的研究，從而對解決有關結晶，擠阻及相轉變等基礎問題提供幫助 。 / Colloidal particies are playing an increasingly important role in a wide range of applications, from rheological modifiers in the paint industry to nanoparticies for targeted drug delivery. By altering interactions between colloidal particies, one can design stable fluids, gels or crystals needed for different purposes. Prior to exploit of a widespread application for colloidal particies, a good understanding of the stability of particies suspension and thus of the interaction between particies in aqueous suspension, are required. / In this thesis two major topics are addressed, and both of them are connected with the use of smaller particies to manipulate the interaction force between larger particies. In the first part of this thesis, I have performed an experimental investigation on the interparticie interaction in a binary particie suspension. The results show that the initial addition of charged nanoparticies can alter the interaction force between charged microparticie and plate surface. When the nanoparticie, microparticie and plate were slightly charged, sufficient nanoparticie deposition on plate occurred, leading to an increased electrostatic repulsion between the surfaces even at low nanoparticie concentration. When the nanoparticies, microparticie and plate were highly charged, the adsorption of nanoparticies onto plate/particie surfaces was hindered. Surprisingly, the addition of nanoparticies also produced a repulsive force. This observed trend is substantially different from the conventional highly charged systems where the addition of nanoparticies creates an attractive depletion force between the microparticie and plate. Our results suggest that these nanoparticies might reside to the region near the plate surface, which eventually give rise to the effective repulsive force. This is the first study to demonstrate that nanoparticie halos can also arise in binary systems of mutually but highly repulsive microparticie/nanoparticie dispersions. We believe that this finding will stimulate theoretians to investigate the nature of such induced interparticie interactions. Our study thus highlights the challenges associated with using charged nanoparticles as a tool to regulate stability in the binary particle systems. / In the second part of this thesis, we extend our study of using smaller charged colloidal particles to alter the interaction force between larger colloidal particles at the fluid-fluid interfaces. We systemically study the binary mixture of colloidal particles at both oil/water and air/water interface. We focus on resolving the interaction forces between confined colloidal particles by using a combination of high tempo-spatial resolution optical microscopy and particle tracking algorithm. Our results show that dipolar-dipolar repulsive force is consistently presented at the both air/water and oil/water systems. The interaction force between charged particles trapped at the fluid interfaces may contain two parts: the dipole-dipole repulsion which is sensitive to the electrolyte content of the water phase, and the electrostatic repulsion arised from the presence of a very small amount of residual electric charge at the particle-oil interface that is insensitive to the electrolyte content of the water phase. Moreover, our results show that the addition of small particle can lead to a 2D depletion attraction, pushing the large particles closer at the interface. Unlike in bulk solution, this depletion force occurs even at very low depletant concentration because there is no need of depletants to reside above and below the larger particles when they are confined at the interfaces. We believe this kind of 2D depletion interaction will stimulate more theoretical simulations in order to provide an insight for answering fundamental questions concerning with crystallization, jamming and other phase transitions. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Xing, Xiaochen. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references. / Abstract also in Chinese. / Chapter 1. --- Interaction of Colloidal Particles in Bulk Solution --- p.1 / Chapter 1.1. --- Interparticle Forces --- p.1 / Chapter 1.1.1. --- Steric Stabilization and Bridging Interaction --- p.1 / Chapter 1.1.2. --- Electrostatic Stabilization --- p.2 / Chapter 1.1.3. --- Depletion Interaction --- p.4 / Chapter 1.1.4. --- Haloing Stabilization --- p.7 / Chapter 1.2. --- Surface Force Measurement Techniques --- p.10 / Chapter 1.3. --- Total Internal Reflection Microscope (TIRM) --- p.12 / Chapter 1.3.1. --- The Technique and Principle --- p.12 / Chapter 1.3.2. --- Measuring the Potentials --- p.18 / Chapter 1.4. --- References and Notes --- p.22 / Chapter 2. --- Direct Measurement of Interaction Forces in Bidispersed Particle Suspension Systems --- p.25 / Chapter 2.1. --- Introduction --- p.25 / Chapter 2.2. --- Interaction Forces in the Bidispersed Systems --- p.28 / Chapter 2.2.1. --- Direct Measurement of the Interaction Forces between Colloidal Particles in a Solution of PS Nanoparticles. --- p.28 / Chapter 2.2.1.1. --- Materials and Methods Materials and Methods Materials and Methods Materials and MethodsMaterials and Methods Materials and Methods --- p.29 / Chapter 2.2.1.2. --- Results Results --- p.32 / Chapter 2.2.1.3. --- Discussion Discussion --- p.41 / Chapter 2.2.2. --- Direct Measurement of the Interaction Forces between Colloidal Particles in a Solution of PS-co-NIPAm Nanoparticles --- p.45 / Chapter 2.3. --- Conclusion --- p.52 / Chapter 2.4. --- References and Notes --- p.54 / Chapter 3. --- Colloidal Particles at Liquid/Liquid Interface --- p.56 / Chapter 3.1. --- Introduction --- p.56 / Chapter 3.2. --- Interactions Forces between Colloidal Particles at Interface --- p.59 / Chapter 3.2.1. --- Repulsive Interactions --- p.63 / Chapter 3.2.2. --- Attractive Interactions --- p.74 / Chapter 3.2.3. --- Force Measurements of Interfacial Particles --- p.79 / Chapter 3.3. --- References and Notes --- p.82 / Chapter 4. --- Direct Measurement of Interaction Force between Colloidal Particles at Fluid Interfaces --- p.88 / Chapter 4.1. --- Materials and Method --- p.90 / Chapter 4.1.1. --- Apparatus and Sample Preparation --- p.90 / Chapter 4.1.2. --- Image processing --- p.92 / Chapter 4.1.3. --- Pair Distribution Function (PDF) and Radial Distribution Function (RDF) --- p.92 / Chapter 4.1.4. --- Pair-Potential of Particle Ensembles --- p.96 / Chapter 4.2. --- Interactions of Particles at Oil (Air)/Water Interface --- p.97 / Chapter 4.2.1. --- Interactions of Monodispersed Colloidal Particles at Oil (Air)/Water Interface --- p.97 / Chapter 4.2.2. --- Effect of Adding Salt on the Interparticle Interaction at Oil(Air)/Water Interface --- p.104 / Chapter 4.2.3. --- Interaction of Binary Particles at Oil/Water Interface --- p.108 / Chapter 4.2.4. --- Effect of Adding Salt on the Binary Particles at the Oil/Water Interface --- p.114 / Chapter 4.2.5. --- Mesostructures at the Interface --- p.118 / Chapter 4.3. --- References and Notes --- p.122