A three-dimensional representation method for noisy point clouds based on growing self-organizing maps accelerated on GPUs

The research described in this thesis was motivated by the need of a robust model capable of representing 3D data obtained with 3D sensors, which are inherently noisy. In addition, time constraints have to be considered as these sensors are capable of providing a 3D data stream in real time. This thesis proposed the use of Self-Organizing Maps (SOMs) as a 3D representation model. In particular, we proposed the use of the Growing Neural Gas (GNG) network, which has been successfully used for clustering, pattern recognition and topology representation of multi-dimensional data. Until now, Self-Organizing Maps have been primarily computed offline and their application in 3D data has mainly focused on free noise models, without considering time constraints. It is proposed a hardware implementation leveraging the computing power of modern GPUs, which takes advantage of a new paradigm coined as General-Purpose Computing on Graphics Processing Units (GPGPU). The proposed methods were applied to different problem and applications in the area of computer vision such as the recognition and localization of objects, visual surveillance or 3D reconstruction.

Nuevas tecnologías en redes WAN y LAN

Los adelantos de la tecnología permiten que las comunicaciones tengan lugar a través de grandes distancias cada vez con mayor facilidad. Los computadores hablan a los computadores; la gente habla a los computadores y los computadores hablan a la gente. Este rápido cambio ha forzado a muchos de los medios corrientes de información hasta sus límites tecnológicos. Nuevas ideas de diseño y conceptos tecnológicos revolucionarios están surgiendo en todas partes, y con ellos la necesidad evidente de mejores sistemas de comunicación que brinden confiabilidad, seguridad y rápido desempeño, siendo nuestro objetivo brindar un conocimiento de los mismos.

Developing strategies to mitigate the energy consumed by network infrastructures

The energy consumption by ICT (Information and Communication Technology) equipment is rapidly increasing which causes a significant economic and environmental problem. At present, the network infrastructure is becoming a large portion of the energy footprint in ICT. Thus the concept of energy efficient or green networking has been introduced. Now one of the main concerns of network industry is to minimize energy consumption of network infrastructure because of the potential economic benefits, ethical responsibility, and its environmental impact. In this paper, the energy management strategies to reduce the energy consumed by network switches in LAN (Local Area Network) have been developed. According to the lifecycle assessment of network switches, during usage phase, the highest amount of energy consumed. The study considers bandwidth, link load and traffic matrixes as input parameters which have the highest contribution in energy footprint of network switches during usage phase and energy consumption as output. Then with the objective of reducing energy usage of network infrastructure, the feasibility of putting Ethernet switches hibernate or sleep mode was investigated. After that, the network topology was reorganized using clustering method based on the spectral approach for putting network switches to hibernate or switched off mode considering the time and communications among them. Experimental results show the interest of this approach in terms of energy consumption

Resilience to Climate Change: An Ethnographic Approach

Global projections for climate change impacts produce a startling picture of the future for low-lying coastal communities. The United States’ Chesapeake Bay region and especially marginalized and rural communities will be severely impacted by sea level rise and other changes over the next one hundred years. The concept of resilience has been theorized as a measure of social-ecological system health and as a unifying framework under which people can work together towards climate change adaptation. But it has also been critiqued for the way in which it does not adequately take into account local perspective and experiences, bringing into question the value of this concept as a tool for local communities. We must be sure that the concerns, weaknesses, and strengths of particular local communities are part of the climate change adaptation, decision-making, and planning process in which communities participate. An example of this type of planning process is the Deal Island Marsh and Community Project (DIMCP), a grant funded initiative to build resilience within marsh ecosystems and communities of the Deal Island Peninsula area of Maryland (USA) to environmental and social impacts from climate change. I argue it is important to have well-developed understandings of vulnerabilities and resiliencies identified by local residents and others to accomplish this type of work. This dissertation explores vulnerability and resilience to climate change using an engaged and ethnographic anthropological perspective. Utilizing participant observation, semi-structured and structured interviews, text analysis, and cultural domain analysis I produce an in-depth perspective of what vulnerability and resilience means to the DIMCP stakeholder network. Findings highlight significant vulnerabilities and resiliencies inherent in the local area and how these interface with additional vulnerabilities and resiliencies seen from a nonlocal perspective. I conclude that vulnerability and resilience are highly dynamic and context-specific for the local community. Vulnerabilities relate to climate change and other social and environmental changes. Resilience is a long-standing way of life, not a new concept related specifically to climate change. This ethnographic insight into vulnerability and resilience provides a basis for stronger engagement in collaboration and planning for the future.

Multiscale Modeling and Simulation of Stepped Crystal Surfaces

A primary goal of this dissertation is to understand the links between mathematical models that describe crystal surfaces at three fundamental length scales: The scale of individual atoms, the scale of collections of atoms forming crystal defects, and macroscopic scale. Characterizing connections between different classes of models is a critical task for gaining insight into the physics they describe, a long-standing objective in applied analysis, and also highly relevant in engineering applications. The key concept I use in each problem addressed in this thesis is coarse graining, which is a strategy for connecting fine representations or models with coarser representations. Often this idea is invoked to reduce a large discrete system to an appropriate continuum description, e.g. individual particles are represented by a continuous density. While there is no general theory of coarse graining, one closely related mathematical approach is asymptotic analysis, i.e. the description of limiting behavior as some parameter becomes very large or very small. In the case of crystalline solids, it is natural to consider cases where the number of particles is large or where the lattice spacing is small. Limits such as these often make explicit the nature of links between models capturing different scales, and, once established, provide a means of improving our understanding, or the models themselves. Finding appropriate variables whose limits illustrate the important connections between models is no easy task, however. This is one area where computer simulation is extremely helpful, as it allows us to see the results of complex dynamics and gather clues regarding the roles of different physical quantities. On the other hand, connections between models enable the development of novel multiscale computational schemes, so understanding can assist computation and vice versa. Some of these ideas are demonstrated in this thesis. The important outcomes of this thesis include: (1) a systematic derivation of the step-flow model of Burton, Cabrera, and Frank, with corrections, from an atomistic solid-on-solid-type models in 1+1 dimensions; (2) the inclusion of an atomistically motivated transport mechanism in an island dynamics model allowing for a more detailed account of mound evolution; and (3) the development of a hybrid discrete-continuum scheme for simulating the relaxation of a faceted crystal mound. Central to all of these modeling and simulation efforts is the presence of steps composed of individual layers of atoms on vicinal crystal surfaces. Consequently, a recurring theme in this research is the observation that mesoscale defects play a crucial role in crystal morphological evolution.

Desarrollo de un método para la evaluación de la gestión de mantenimiento de edificios multifamiliares ubicados en la ciudad de Cuenca

El deterioro es un proceso que afecta a toda edificación y una de sus causas es el mantenimiento deficiente. El mantenimiento involucra a actividades técnicas, administrativas y de gestión necesarias para conservar a una edificación o devolverle a un estado en el que pueda realizar la función requerida. Identificar cuál es el desempeño de un edificio en el área de la gestión de mantenimiento resulta preciso. Por lo cual el objetivo de este estudio es desarrollar un método para la evaluación de la gestión de mantenimiento en edificios multifamiliares ubicados en la ciudad de Cuenca. Para el efecto, es necesario responder las preguntas ¿cuáles son los requerimientos y criterios para la evaluación de la gestión de mantenimiento de edificios multifamiliares? y ¿cuáles son sus ponderaciones?, considerando el contexto local de la ciudad de Cuenca. La investigación se desarrolla en tres fases, empieza por la determinación de los criterios de evaluación; priorización de los requerimientos y criterios seleccionados, para lo cual se emplea el método AnalyticHierarchyProcess a través de la consulta a expertos: arquitectos, administradores de edificios y profesionales con grado de maestría en gestión de mantenimiento, se finaliza desarrollando el método de evaluación. El estudio determina que los requerimientos más importantes de la gestión de mantenimiento de edificios multifamiliares, en el área local son: el diseño del edificio, los riesgos laborales en el mantenimiento y la planificación, programación y control del mantenimiento. La metodología ha sido aplicada satisfactoriamente a un edificio multifamiliar en la ciudad de Cuenca.

Load frequency control of power systems with electric vehicles and diverse transmission links using distributed functional observers

This paper presents a load frequency control scheme using electric vehicles (EVs) to help thermal turbine units to provide the stability fluctuated by load demands. First, a general framework for deriving a state-space model for general power system topologies is given. Then, a detailed model of a four-area power system incorporating a smart and renewable discharged EVs system is presented. The areas within the system are interconnected via a combination of alternating current/high voltage direct current links and thyristor controlled phase shifters. Based on some recent development on functional observers, novel distributed functional observers are designed, one at each local area, to implement any given global state feedback controller. The designed observers are of reduced order and dynamically decoupled from others in contrast to conventional centralized observer (CO)-based controllers. The proposed scheme can cope better against accidental failures than those CO-based controllers. Extensive simulations and comparisons are given to show the effectiveness of the proposed control scheme.

Modeling, Simulation, and Characterization of Space Debris in low-Earth Orbit

Every space launch increases the overall amount of space debris. Satellites have limited awareness of nearby objects that might pose a collision hazard. Astrometric, radiometric, and thermal models for the study of space debris in low-Earth orbit have been developed. This modeled approach proposes analysis methods that provide increased Local Area Awareness for satellites in low-Earth and geostationary orbit. Local Area Awareness is defined as the ability to detect, characterize, and extract useful information regarding resident space objects as they move through the space environment surrounding a spacecraft. The study of space debris is of critical importance to all space-faring nations. Characterization efforts are proposed using long-wave infrared sensors for space-based observations of debris objects in low-Earth orbit. Long-wave infrared sensors are commercially available and do not require solar illumination to be observed, as their received signal is temperature dependent. The characterization of debris objects through means of passive imaging techniques allows for further studies into the origination, specifications, and future trajectory of debris objects. Conclusions are made regarding the aforementioned thermal analysis as a function of debris orbit, geometry, orientation with respect to time, and material properties. Development of a thermal model permits the characterization of debris objects based upon their received long-wave infrared signals. Information regarding the material type, size, and tumble-rate of the observed debris objects are extracted. This investigation proposes the utilization of long-wave infrared radiometric models of typical debris to develop techniques for the detection and characterization of debris objects via signal analysis of unresolved imagery. Knowledge regarding the orbital type and semi-major axis of the observed debris object are extracted via astrometric analysis. This knowledge may aid in the constraint of the admissible region for the initial orbit determination process. The resultant orbital information is then fused with the radiometric characterization analysis enabling further characterization efforts of the observed debris object. This fused analysis, yielding orbital, material, and thermal properties, significantly increases a satellite’s Local Area Awareness via an intimate understanding of the debris environment surrounding the spacecraft.

Australian native gardens: Is there scope for a community shift?

The negative impacts of urbanization on biodiversity are well known, and the use of native vegetation in private gardens and streetscapes have been shown to improve the species richness and abundance of native wildlife, thereby improving the biodiversity of the local area. This study poses the question of whether the general public is interested in planting native species, to determine whether a cultural shift in garden planting style is feasible. A total of 3707 questionnaires relating to nature in the backyard were delivered to residents in metropolitan Melbourne, Australia with 417 responses received (11.2% response rate). The results indicate that the public perception of the aesthetic appeal of native gardens is fairly positive and that Melbournians have considerable interest in planting native species in residential gardens and that a large number would like wildlife in their yards. The paper concludes that there is scope to encourage the use of native plants in residential landscaping.

Mothers’ ideals and experiences of raising children in inner and outer suburban Melbourne, Australia

Parents’ perceptions of their neighbourhoods are important for child health outcomes. This study compared views among mothers in inner versus outer suburbs of Melbourne, Australia using a mixed methods approach. Mothers of preschool-aged children were recruited via playgroups, mother’s groups and preschools and interviewed face-to-face regarding their local area as a good place to raise a family, with a second open-ended interview focussing on mothers’ ideals and experiences of raising children in their current location. Findings demonstrated that mothers had different ideals for, and experiences of, raising their children in their neighbourhoods. Inner suburban mothers valued a manageable work/family balance and access to public transport over the size of their homes. However, access to childcare, secondary schooling and heavy traffic were issues, with the latter two being reasons for moving from the municipality. In contrast, outer suburban mothers preferred a larger home in neighbourhoods that they perceived as low crime, over accessibility to work. Access to a car and activities for their children were also important. Findings suggest no ‘one size fits all’ in respect to what features mothers expect from a good place to raise a family, or how they experience these features. This has implications for service delivery and social planning of suburbs.

Library, Archives and Museum Annual Assessment Report, 2004-2005

The Library, Archives and Museum are a major component of South Carolina’s only state-assisted military college, The Citadel. They participate in the teaching, research, and public service programs of The Citadel: by providing scholarly information; by the acquisition, organization, management, preservation, and arrangement of collections for access and use; by provision of supportive reference and instruction services; and by a variety of cooperative and reciprocal programs in the local area, the region and the state. This annual report discusses their activities for the year 2004/05.

South Carolina's employment situation-April 2010

The South Carolina Department of Employment and Workforce publishes news releases with monthly statistics about the employment situation of the state, including unemployment rate, employment by industry, and local area unemployment by county and MSA.

South Carolina's employment situation-May 2010

The South Carolina Department of Employment and Workforce publishes news releases with monthly statistics about the employment situation of the state, including unemployment rate, employment by industry, and local area unemployment by county and MSA.

South Carolina's employment situation-July 2010

The South Carolina Department of Employment and Workforce publishes news releases with monthly statistics about the employment situation of the state, including unemployment rate, employment by industry, and local area unemployment by county and MSA.

South Carolina's employment situation-October 2010

The South Carolina Department of Employment and Workforce publishes news releases with monthly statistics about the employment situation of the state, including unemployment rate, employment by industry, and local area unemployment by county and MSA.