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This is a study of the change in property values over a ten year period, from 1993 to 2003, in New Orleans, Louisiana. Sales prices for the entire city are compared to sales prices in two locally designated historic districts and one control neighborhood. The intent of the paper is to identify the effect that local historic protections have on real property values.

<p>In this paper we examine the need of navigational aids when designing interfaces for e-newspapers </p><p>– newspapers presented on a digital paper built on E-Ink technology. By reviewing literature on </p><p>navigation, and by handling input from both newspaper designers and potential e-newspaper </p><p>adopters, we have suggested a number of navigational aids for the future e-newspaper. Our </p><p>suggestions have been tested through a prototype using a modification of the Cooperative </p><p>Usability Testing model (CUT) on a total of fifteen potential users. The results show that most </p><p>users prefer a linear organization of the e-newspaper. To render a sense of depth in this flat </p><p>medium, page-numbering is essential. Several different interaction possibilities will also be </p><p>needed to ease the navigation and our suggestions include a blend of page-turning and hyper </p><p>linking, combined with an index to give the user a better overview of the content.</p>

In this paper we examine the need of navigational aids when designing interfaces for e-newspapers – newspapers presented on a digital paper built on E-Ink technology. By reviewing literature on navigation, and by handling input from both newspaper designers and potential e-newspaper adopters, we have suggested a number of navigational aids for the future e-newspaper. Our suggestions have been tested through a prototype using a modification of the Cooperative Usability Testing model (CUT) on a total of fifteen potential users. The results show that most users prefer a linear organization of the e-newspaper. To render a sense of depth in this flat medium, page-numbering is essential. Several different interaction possibilities will also be needed to ease the navigation and our suggestions include a blend of page-turning and hyper linking, combined with an index to give the user a better overview of the content.

Libraries are filled with indistinct landmarks, such as rows of identical bookshelves, which make it difficult for patrons to navigate and locate books. Call numbers are the primary resource that can be utilized while locating books, and these consist of letters and digits that are incomprehensible to many library users. With libraries increasingly offering both physical and digital resources and mobile devices being more common, we aimed to investigate the potential for mobile devices to assist in locating books within the complex physical spaces of libraries.

Rats learn to navigate to a specific location faster in a familiar environment (Keith and Mcvety 1988). It has been proposed that place learning does not require specific reward signals, but rather, that it occurs automatically. One of the strongest pieces of evidence for the automatic nature of place learning comes from the observation that place and head direction cells reference their receptive fields to prominent landmarks in an environment without needing a reward signal (O’Keefe and Conway 1978; Taube et al. 1990b). It has also been proposed that an allocentric representation of an environment would be bound to the landmarks with the greatest relative stability to guide its orientation (O’Keefe and Nadel 1978). The first two parts of this thesis explore whether place and head direction cells automatically use the most coherent landmarks for orientation. Head direction cells have been shown to orient their preferred firing directs coherently when being exposed to conflicting landmarks in an environment (Yoganarasimha et al. 2006). A model of head direction cells was thus used to explore the necessary mechanisms required to implement an allocentric system that selects landmarks based on their relative stability. We found that the simple addition of Hebbian projections combined with units representing the orientation of landmarks to the head direction cell system is sufficient for the system to exhibit such a capacity. We then recorded both entorhinal head direction cells and CA1 place cells and at the same time subjected the rats to repeated experiences of landmark conflicts. During the conflicts a subset of landmarks always maintained a fixed relative relationship with each other. We found that the visual landmarks retained their ability to control the place and head direction cells even after repeated experience of conflict and that the simultaneously recorded place cells exhibited coherent representations between conflicts. However, the ’stable landmarks’ did not show significantly greater control over the place and head direction cells when comparing to the unstable landmarks. This argues against the hypothesis that the relative stability between landmarks is encoded automatically. We did observe a trend that, with more conflict experience, the ’stable landmarks’ appeared to exert greater control over the cells. The last part of the thesis explores whether goal sensitive cells (Ainge et al. 2007a) discovered from CA1 of hippocampus are developed due to familiarity with the environment or from the demands for rats to perform a win-stay behaviour. We used the same win-stay task as in Ainge et al. and found that there were few or no goal sensitive cells on the first day of training. Subsequent development of goal sensitive activity correlated significantly with the rat’s performance during the learning phase of the task. The correlation provides support to the hypothesis that the development of goal sensitive cells is associated to the learning of the win-stay task though it does not rule out the possibility that these goal sensitive cells are developed due to the accumulated experience on the maze. In summary, this thesis explores what kind of spatial information is encoded by place and head direction cells and finds that relative stability between landmarks without a reward signal is not automatically encoded. On the other hand, when additional information is required to solve a task, CA1 place cells adapt their spatial code to provide the necessary information to guide successful navigation.

Providing unambiguous, succinct descriptions of routes for pedestrians to follow is very challenging. Route descriptions vary according to many things, such as route length and complexity, availability of easily identifiable landmarks, and personal preferences. It is well known that the inclusion of a variety of landmarks facilitates route following – either at key decision points, or as a confirmatory cue. Many of the existing solutions, however, behave like car navigation systems and do not include references to such landmarks. The broader ambition of this research is the automatic generation of route descriptions that cater specifically to the needs of the pedestrian. More specifically this research describes empirical evidence gathered to identify the information requirements for an automated pedestrian navigation system. The results of three experiments helped to identify the criteria that govern the relative saliency of features of interest within an urban environment. There are a large variety of features of interest (together with their descriptions) that can be used as directional aids within route descriptions (for example buildings, statues, monuments, hills, and roads). A set of variables were developed in order to measure the saliency of the different classes of features. The experiments revealed that the most important measures of saliency included name, size, age, and colour. This empirical work formed the basis of the development of a pedestrian navigation system that incorporated the automatic identification of features of interest using the City of Edinburgh as the study area. Additionally the system supported the calculation of the saliency of a feature of interest, the development of an intervisibility model for the route to be navigated to determine the best feature of interest to use at each decision point along the route. Finally, the pedestrian navigation system was evaluated against route descriptions gathered from a random set of individuals to see how efficiently the system reflected the more natural and richer route description that people typically generate. This work shows that modelling features of interest is the key to the automatic generation of route descriptions that can be readily understood and followed by pedestrians.

Thesis (M.A.)--Carleton University, 1988. / Also available in electronic format on the Internet.

En los métodos actuales de SLAM visual, los mapas son representados mediante landmarks puntuales. Como la observación de un landmark puntual entrega sólo información angular sobre la cámara, se debe estimar una matriz de covarianza que considere todos los puntos para poder converger a una escala global. Sin embargo, como la complejidad computacional asociada al trabajo con matrices de covarianza crece de una forma cuadrática respecto al número de landmarks, la cantidad máxima de puntos con los cuales se puede trabajar n tiempo real está limitada a unos cientos. En este trabajo se propone un sistema de SLAM visual basado en el uso de los denominados landmarks cuerpo rígido. Un landmark cuerpo rígido representa la pose completa 6D (posición y orientación) de un cuerpo rígido en el espacio, y la observación de uno de estos landmarks proporciona información completa acerca de la pose de una cámara móvil. Cada landmarks cuerpo rígido es creado a partir de un conjunto de N landmarks puntuales mediante el colapso de 3N componentes del estado en 7 nuevas componentes del estado, además de un conjunto de parámetros que describe la forma del landmark. Los landmark cuerpo rígido son representados y estimados usando puntocuaterniones, los cuales son introducidos en este trabajo. Mediante el uso de los landmarks cuerpo rígido, el tiempo de ejecución del sistema de SLAM puede reducirse hasta un 5.5% a medida que la cantidad de landmarks aumenta. El sistema SLAM propuesto es validado y simulado en secuencias de video reales. El método propuesto puede ser extendido a cualquier sistema de SLAM que se base en el uso de landmarks puntuales, incluyendo aquellos generados mediante sensores láser.

Recent inquiry into the nomenclature of several species within Spinocyrtia has led to questions concerning name applicability and validity, particularly whether Delthyris granulosa and Spinocyrtia (Spirifer) granulosa are synonymous. This study utilized two-dimensional outline landmark analysis, a form of geometric morphometric analysis, to evaluate interspecific variation among these species. I took over a thousand photographs of over a hundred specimens of brachiopods belonging to the family Spinocyrtiidae. Ninety-six specimens originated from the Givetian outcrop belt of New York state, three were from northwestern Ohio, there was single Canadian specimen, and there was a single German specimen. The results from these analyses indicate that the mophospaces of Spinocyrtia (Spirifer) congesta, S. (Spirifer) granulosa, and S?. (Spirifer) marcyi are statistically (p < 0.05) distinct from one another.