Location Area Planning Using Simulated Annealing With A New Solution Representation

Location area planning problem is to partition the cellular/mobile network into location areas with the objective of minimizing the total cost. This partitioning problem is a difficult combinatorial optimization problem. In this paper, we use the simulated annealing with a new solution representation. In our method, we can automatically generate different number of location areas using Compact Index (CI) to obtain the optimal/best partitions. We compare the results obtained in our method with the earlier results available in literature. We show that our methodology is able to perform better than earlier methods.

El pulso urbano-industrial de O Porriño

En el planteamiento de la presente disertación, se tienen en consideración las premisas sobre los orígenes de la ciudad, su influencia industrial y su resolución a través de la Teoría de la Lógica Social del Espacio como herramienta de trabajo para los análisis sobre los planes urbanos propuestos para el municipio a estudio, su historia y para la elaboración de propuestas de interacción futuras. Inicialmente, la propuesta surge de la importancia de las vías de comunicación, como elemento creador urbano, es decir, de una determinada infraestructura, la calle-carretera como el “eje” de consolidación de la ciudad, donde se realizan la mayoría de recorridos o flujos en este caso, ejemplificado en la villa de Porriño. El urbanismo pos-moderno, hasta finales de 1970 e inicios de 1980, no abordaba una articulación entre social y técnica, una ciencia de lucha de clases. En este contexto, en 1984, Bill Hillier y Julienne Hanson escriben “La Lógica Social del Espacio” donde argumentan que los movimientos o flujos obedecen a una lógica racional, según la cual, cualquier desplazamiento es llevado a cabo por el menor recorrido y, por tanto, el urbanismo influye en esos flujos. La configuración urbana genera condiciones de accesibilidad y da origen a una diferenciación espacial jerarquizada con conceptos como la conectividad, integración y segregación en un espacio influenciado y construido por la dinámica social. De este modo, la Teoría de la Sintaxis Espacial describe la configuración del trazado urbano y las relaciones entre el espacio público y privado a través de medidas cuantitativas, las cuales permiten entender aspectos importantes del sistema urbano como la accesibilidad y la distribución y usos del suelo consolidado. Por tanto, en la teoría existe una correlación establecida entre las propiedades de los elementos presentados, espacio y sociedad, de modo que cada elemento incumbe al otro y no existiría sin su presencia, siendo fundamental para la definición de la forma. Esta herramienta, Space Syntax, busca la integración del espacio en la ciudad, mediante un análisis y una evaluación a diversas escalas en la red urbana, con una correcta distribución de los espacios, sus usos y las vías de transporte o comunicación necesarios para llegar a los diferentes lugares de la ciudad. La realización de la investigación se centrará en el análisis de la infraestructura viaria en el municipio de Porriño y sus regiones colindantes a lo largo del período histórico analizado, centrándose en tres momentos históricos, 1956, 1986 y la actualidad 2015, debido a los vuelos fotogramétricos de dichas etapas. Así, se obtendrán las respectivas mediciones correspondientes a través del programa informático Depthmap, las cuales se contrarrestarán y compararán entre sí en cada etapa analizada y entre los propios años examinados, para lograr obtener las consideraciones establecidas a lo largo del estudio en cuanto a la influencia comunicativa de los flujos de interacción social en el entorno urbano definido y la respectiva lucha de los sectores industriales y residenciales. En conclusión, se pretende la justificación del origen de la ciudad a través de la comparación sus vías, las cuales fueron fomentadas por el comercio e industria para su creación, dotando así a la industria del dominio del espacio para satisfacer sus necesidades, creando y ampliando su área de intervención, la cual puede ser analizada y tratada no sólo independientemente, sino en el conjunto urbano en el que se sitúa, Porriño.

Drug interaction and location in liposomes: correlation with polar surface areas

An important step in liposome characterization is to determine the location of a drug within the liposome. This work thus investigated the interaction of dipalmitoylphosphatidylcholine liposomes with drugs of varied water solubility, polar surface area (PSA) and partition coefficient using high sensitivity differential scanning calorimetry. Lipophilic estradiol (ES) interacted strongest with the acyl chains of the lipid membrane, followed by the somewhat polar 5-fluorouracil (5-FU). Strongly hydrophilic mannitol (MAN) showed no evidence of interaction but water soluble polymers inulin (IN) and an antisense oligonucleotide (OLG), which have very high PSAs, interacted with the lipid head groups. Accordingly, the drugs could be classified as: hydrophilic ones situated in the aqueous core and which may interact with the head groups; those located at the water-bilayer interface with some degree of penetration into the lipid bilayer; those lipophilic drugs constrained within the bilayer. (c) 2004 Elsevier B.V. All rights reserved.

Methodological issues in applying Location Models to Rural areas

Location Models are usedfor planning the location of multiple service centers in order to serve a geographicallydistributed population. A cornerstone of such models is the measure of distancebetween the service center and a set of demand points, viz, the location of thepopulation (customers, pupils, patients and so on). Theoretical as well asempirical evidence support the current practice of using the Euclidian distancein metropolitan areas. In this paper, we argue and provide empirical evidencethat such a measure is misleading once the Location Models are applied to ruralareas with heterogeneous transport networks. This paper stems from the problemof finding an optimal allocation of a pre-specified number of hospitals in alarge Swedish region with a low population density. We conclude that the Euclidianand the network distances based on a homogenous network (equal travel costs inthe whole network) give approximately the same optimums. However networkdistances calculated from a heterogeneous network (different travel costs indifferent parts of the network) give widely different optimums when the numberof hospitals increases.  In terms ofaccessibility we find that the recent closure of hospitals and the in-optimallocation of the remaining ones has increased the average travel distance by 75%for the population. Finally, aggregation the population misplaces the hospitalsby on average 10 km.

How does the use of different road networks effect the optimal location of facilities in rural areas?

The p-median problem is often used to locate P service facilities in a geographically distributed population. Important for the performance of such a model is the distance measure. Distance measure can vary if the accuracy of the road network varies. The rst aim in this study is to analyze how the optimal location solutions vary, using the p-median model, when the road network is alternated. It is hard to nd an exact optimal solution for p-median problems. Therefore, in this study two heuristic solutions are applied, simulating annealing and a classic heuristic. The secondary aim is to compare the optimal location solutions using dierent algorithms for large p-median problem. The investigation is conducted by the means of a case study in a rural region with an asymmetrically distributed population, Dalecarlia. The study shows that the use of more accurate road networks gives better solutions for optimal location, regardless what algorithm that is used and regardless how many service facilities that is optimized for. It is also shown that the simulated annealing algorithm not just is much faster than the classic heuristic used here, but also in most cases gives better location solutions.

THE MULTIPLE LOCATION TIME WEIGHTED INDEX: USING PATIENT ACTIVITY SPACES TO CALCULATE PRIMARY CARE SERVICE AREAS

Geographic health planning analyses, such as service area calculations, are hampered by a lack of patient-specific geographic data. Using the limited patient address information in patient management systems, planners analyze patient origin based on home address. But activity space research done sparingly in public health and extensively in non-health related arenas uses multiple addresses per person when analyzing accessibility. Also, health care access research has shown that there are many non-geographic factors that influence choice of provider. Most planning methods, however, overlook non-geographic factors influencing choice of provider, and the limited data mean the analyses can only be related to home address. This research attempted to determine to what extent geography plays a part in patient choice of provider and to determine if activity space data can be used to calculate service areas for primary care providers. During Spring 2008, a convenience sample of 384 patients of a locally-funded Community Health Center in Houston, Texas, completed a survey that asked about what factors are important when he or she selects a health care provider. A subset of this group (336) also completed an activity space log that captured location and time data on the places where the patient regularly goes. Survey results indicate that for this patient population, geography plays a role in their choice of health care provider, but it is not the most important reason for choosing a provider. Other factors for choosing a health care provider such as the provider offering “free or low cost visits”, meeting “all of the patient’s health care needs”, and seeing “the patient quickly” were all ranked higher than geographic reasons. Analysis of the patient activity locations shows that activity spaces can be used to create service areas for a single primary care provider. Weighted activity-space-based service areas have the potential to include more patients in the service area since more than one location per patient is used. Further analysis of the logs shows that a reduced set of locations by time and type could be used for this methodology, facilitating ongoing data collection for activity-space-based planning efforts.

The multiple location time weighted index: Using patient activity spaces to calculate primary care service areas

Geographic health planning analyses, such as service area calculations, are hampered by a lack of patient-specific geographic data. Using the limited patient address information in patient management systems, planners analyze patient origin based on home address. But activity space research done sparingly in public health and extensively in non-health related arenas uses multiple addresses per person when analyzing accessibility. Also, health care access research has shown that there are many non-geographic factors that influence choice of provider. Most planning methods, however, overlook non-geographic factors influencing choice of provider, and the limited data mean the analyses can only be related to home address. This research attempted to determine to what extent geography plays a part in patient choice of provider and to determine if activity space data can be used to calculate service areas for primary care providers. ^ During Spring 2008, a convenience sample of 384 patients of a locally-funded Community Health Center in Houston, Texas, completed a survey that asked about what factors are important when he or she selects a health care provider. A subset of this group (336) also completed an activity space log that captured location and time data on the places where the patient regularly goes. ^ Survey results indicate that for this patient population, geography plays a role in their choice of health care provider, but it is not the most important reason for choosing a provider. Other factors for choosing a health care provider such as the provider offering "free or low cost visits", meeting "all of the patient's health care needs", and seeing "the patient quickly" were all ranked higher than geographic reasons. ^ Analysis of the patient activity locations shows that activity spaces can be used to create service areas for a single primary care provider. Weighted activity-space-based service areas have the potential to include more patients in the service area since more than one location per patient is used. Further analysis of the logs shows that a reduced set of locations by time and type could be used for this methodology, facilitating ongoing data collection for activity-space-based planning efforts. ^

Location of uranium deposits in southwestern North Dakota and the Cave Hills and Slim Buttes Areas, Harding County, South Dakota.

"July, 1956."

Between the centre and the margins: Services location, economic (re)structuring and quality of life in metropolitan periurban areas.

This paper aims to discuss the specificities of the role of services in the economic structuring and in the social liveliness and attractiveness of periurban areas. Drawing upon on the result of an empirical work developed in 5 different parishes of Lisbon Metropolitan area, which represent five categories of periurban spaces previously identified, it is analysed the role of services in these “in-between” territories and the way they are important in the spatial economic structuring of these areas and in the quality of life and well-being of their inhabitants and users. A tentative typology for framing the analysis of the role of services on periurban metropolitan spaces is suggested and some policy implications are pointed out.