River basin planning in Nigeria

This paper discusses the concept and practice of river basin planning in Nigeria. The first River Basin Development Authorities (RBDAs) were established in 1973 and the number was increased to nine in 1979. A number of major water resource projects were developed during the 1970s, particularly dam and irrigation schemes. In this paper the importance of political factors in river basin planning is discussed, and planning in two particular basins is described. In the Gongola River Basin the pattern of project development demonstrates the lack of integrated basin planning, and in the Sokoto River Basin adverse environmental impacts occurred when one project was developed without consideration of the resources of the rest of the basin. The disappointing economic performance and social impacts of RBDA schemes are described, and the future contribution of river basin planning to development in Nigeria is discussed.     

A data model for multi-dimensional transportation applications

The distinctive data management needs of transportation agencies in developing transportation-based applications dictate the presence of essential elements that are beyond existing transportation location referencing system data models. These elements include multi-dimensional location referencing, multiscale representation, navigation, and temporal GIS. This paper looks at the foundation for these elements, describes the characteristics of these elements and offers solutions through a transportation-based multi-dimensional data model. By managing data expressed in one to four dimensions, the Multi-Dimensional Location Referencing System (MDLRS) data model allows organizations to implement improved solutions for transportation systems using advanced spatial technologies (e.g. GPS).     

Thematic signatures for cleansing and enriching place-related linked data

There has been significant progress transforming semi-structured data about places into knowledge graphs that can be used in a wide variety of geographic information systems such as digital gazetteers or geographic information retrieval systems. For instance, in addition to information about events, actors, and objects, DBpedia contains data about hundreds of thousands of places from Wikipedia and publishes it as Linked Data. Repositories that store data about places are among the most interlinked hubs on the Linked Data cloud. However, most content about places resides in unstructured natural language text, and therefore it is not captured in these knowledge graphs. Instead, place representations are limited to facts such as their population counts, geographic locations, and relations to other entities, for example, headquarters of companies or historical figures. In this paper, we present a novel method to enrich the information stored about places in knowledge graphs using thematic signatures that are derived from unstructured text through the process of topic modeling. As proof of concept, we demonstrate that this enables the automatic categorization of articles into place types defined in the DBpedia ontology (e.g., mountain) and also provides a mechanism to infer relationships between place types that are not captured in existing ontologies. This method can also be used to uncover miscategorized places, which is a common problem arising from the automatic lifting of unstructured and semi-structured data.     

Tsunami mapping in the Gulf of Guayaquil,Ecuador, due to local seismicity

The North-Andean subduction zone generates recurrent tsunamigenic earthquakes. The seismicity is usually considered to be segmented because of different specific morphological features of the Nazca Plate driving the subduction motion. Most of the recent powerful earthquakes in the margin were located in its northern part. To the south, the region of the Gulf of Guayaquil, only (undocumented) three events in 1901, 1933 and 1953 were possibly powerful and tsunamigenic. Here we are interested in the tsunami signature due to local seismicity. Two realistic earthquake scenarios (M_w = 7 and M_w = 7.5) taking into account the hypothesized segmentation of the area are proposed. Their return period is supposed to be intra-centenary. Then, a larger magnitude unsegmented M_w = 8 scenario is computed (half-millennium return period). The interior of the Gulf of Guayaquil as well as the Santa Elena Peninsula are sheltered areas including numerous coastal infrastructures and the city of Guayaquil. It is predicted that potential flooding would occur at high tide only for both segmented and unsegmented scenarios in (1) south of Playas with however only a few centimeters of wave height and (2) Chanduy (a few meters). Both are important zones of coastal farms.     

HOUSING MARKETS IN THE TWILIGHT OF MATERIALISM

Local housing markets mediate national growth of the housing stock and of household numbers. Unearned capital gains on housing for some homeowners produce corrosive effects resembling those generated by excessive material rewards in certain service industries. Excesses of a political economy driven by fair and unfair materialistic drives camouflage the arrival of a global information society whose terms of power and participation take non-material forms. Housing as shelter and neighborhood starts to replace housing as speculative investment and status symbol.     

A confirmed earthquake in continental Antarctica

Summary. An earthquake of magnitude ( M _b) 4.5 has been located by the International Seismological Centre, near 81°S, 37°E in the continental platform of east Antarctica, about 1200 km from the coast of Dronning Maud Land, and 500 km from the Pole of Inaccessibility. The event was found by the Centre's 'search' procedure, which is undertaken with a deliberate delay of about two years. It occurred on 1982 November 4, and its position is well determined from five stations in Antarctica, and four farther afield. This is the first earthquake definitely located in the interior of the Antarctic continent, although there have been some earlier less well established claims, and other earthquakes have occurred near the coast, or associated with areas of volcanism or ice movement.     

A GEOGRAPHICAL BASIS FOR URBAN PUBLIC POLICY

Policy makers express concern for rapid growth and decline of metropolitan regions and of urban neighborhoods. These changes are the net result of families trying to improve themselves socioeconomically and geographically. Recent school intergration trends highlight the many differences between the North and South. The differences in physical and human geography of these regions must be recognized so that effective public policy can be developed.     

Differential rotation of photospheric magnetic fields associated with coronal holes

An interesting aspect of solar rotation is the fact that coronal holes seem to exhibit little or no differential rotation. We set out to investigate the question of whether or not the photospheric magnetic fields underlying coronal holes also exhibit reduced differential rotation. In order to accomplish this we measured the daily positions of filaments and plages surrounding a large coronal hole that lasted for several disk passages. The resulting differential rotation curve was considerably flatter than the standard curve for long-lived filaments and was in remarkably good agreement with the curve found for the overlying coronal hole itself.