Managing spatial uncertainty using attribute,geometric, and neighborhood measures in an empirical rule-based model approach

 A rule-based model for managing uncertainty in spatial databases is presented. The overall goal of the model is to allow a user to assign to a single map class each polygon whose class is not entirely certain using more information than only the map class attributes of such polygons (that are herein termed abjects). This situation might arise when multiple map realizations of an area are available and interpreters/cartographers are not in agreement as to what class is present at a given location or when a digital image is classified by algorithmic/probabilistic means. The scale-based model developed relies on attribute, geometric, and neighborhood measures of abjects arranged in a hierarchical rule-based structure. Structural knowledge of these measures leads to the procedural knowledge that determines what action – e.g., merge, reclassify, retain – is to be taken for a given abject. The wider applicability of the model and associated methodology is also discussed. Received: 5 July 2001 / Accepted: 11 April 2002     

Variations in seasonal rainfall in Southern Europe during the present century: relationships with the North Atlantic Oscillation and the El Niño-Southern Oscillation

 Analysis of data from seventeen rainfall stations in the Iberian Peninsula, Balearic Islands and Northern Africa has revealed significant El Ni?o-Southern Oscillation (ENSO) signals in Europe. Both North Atlantic Oscillation (NAO) and Southern Oscillation (SO) exert an influence on Iberian climate, but at different temporal and spatial scales. Though most of the peninsula is under NAO influence in winter, some stations in the eastern region show no connection with this phenomenon. The same is found for ENSO, with a positively correlated region appearing in the eastern part of Spain, while the rest of the peninsula remains insensitive. The correlation between ENSO and Iberian rainfall has increased towards the end of the present century, with strong positive signals spanning over half of the area studied. The percentage of springtime variability due to ENSO has similarly increased, reaching up to 50% in certain areas. We also show how there are outstanding climatic sensors of these phenomena such as Lake Gallocanta, which manifests a positive response to ENSO while appears insensitive to NAO. Common long-term patterns are observed between SOI and an inferred lake level series, suggesting a constant influence of the low-frequency component of ENSO throughout the period considered. Lake drying phases every 14 years reflect the impact of this signal, approximately every four ENSO events. Received: 6 June 1996/Accepted: 30 October 1996     

Trace element concentrations in nesting flatback turtles (Natator depressus) from Curtis Island, Queensland, Australia

The blood and eggs of the flatback turtle (Natator depressus) sampled when nesting at Curtis Island, Queensland, Australia. In the blood, zinc was present at the highest concentration of 151.15 ± 1.45 μg/L followed by copper (7.74 ± 0.09 μg/L). Lead was found only in some individuals. The measured trace elements in the blood were maternally transferred into the eggs. Other metals and metalloids detected in eggs were chromium, manganese, arsenic and selenium. Eggs showed a more complex trace element profile than blood, suggesting that they provided more representative tissues for determining maternal levels of trace element accumulation in N. depressus. Intra-clutch variation was over 15% for most of the studied trace elements suggesting one egg is not in sufficient to determine trace element accumulation within a clutch. Copper was the only element which was positively correlated with breeding age. Furthermore, no detectable levels of tin compound derivates were measured in N. depressus.     

Effect Of A Heat Island On The Meteorology Of A Complex Urban Airshed

A three-dimensional mesoscale model was used to study the effect of an urban heat island in a relatively complex situation. A heat emission inventory was carried out for an urban airshed thatincludes sources such as motor vehicles, waste heat from industries and electricity consumption. To demonstrate the relative significance of anthropogenic heat flux and variant surface characteristics, three model simulations were conducted. In the first simulation, anthropogenic heat flux was ignored and non-variant surface properties were considered for the entire modelling domain. In the second simulation, variant surface characteristics were considered. While in the third simulation, gridded anthropogenic heat flux and variant surface characteristic were utilised. From these experiments, it was inferred that an additional source of heat in urban areas can substantially affect the wind and temperature regime under light wind conditions. During the day, the anthropogenic heat flux has minimum effect on the urban temperature, however it magnifies the intensity of the convergence near the urban areas.     

The Export Behavior of Small Canadian Manufacturing Firms*

This paper reports on a survey of the export behavior of small Canadian manufacturing firms. An analysis of tables (ANOTA) model is used to describe the relationship between export performance and market characteristics. The export transactions of these firms are also examined using ANOTA and latent class analysis. The relationship between export experience and geographic diversification predicted by stages of development models is confirmed. In addition, two types of export transactions are identified: (1) active exports that help firms reach a market of sufficient size and (2) passive exports in response to demand from foreign customers.     

Enhanced rock‐slope failure following ice‐sheet deglaciation: timing and causes

The temporal pattern of rock‐slope failures (RSFs) following Late Pleistocene deglaciation on tectonically stable terrains is controversial: previous studies variously suggest (1) a rapid response due to removal of supporting ice (‘debuttressing’), (2) a progressive decline in RSF frequency, and (3) a millennial‐scale delay before peak RSF activity. We test these competing models through beryllium‐10 (¹⁰Be) exposure dating of five closely‐spaced quartzite RSFs on the Isle of Jura, Scotland, to establish the relationship between timing of failure and those of deglaciation, episodes of rapid warming and periods of rapid glacio‐isostatic uplift. All five dated RSFs occurred at least 720–2240 years after deglaciation, with the probability of failure peaking ~2 ka after deglaciation, consistent with millennial‐scale delay model (3). This excludes debuttressing as an immediate cause of failure, though it is likely that time‐dependent stress release due to deglacial unloading resulted in progressive development of failure planes within the rock. Thaw of permafrost ice in joints is unlikely to have been a prime trigger of failure as some RSFs occurred several centuries after the onset of interstadial warming. Conversely, the timespan of the RSFs coincides with the period of maximum glacio‐isostatic crustal uplift, suggesting that failure was triggered by uplift‐driven seismic events acting on fractured rock masses. Implications of this and related research are: (1) that retreat of the last Pleistocene ice sheets across tectonically‐stable mountainous terrains was succeeded by a period of enhanced rock‐slope failure due to deglacial unloading and probably uplift‐driven seismicity; (2) that the great majority of RSFs in the British Isles outside the limits of Loch Lomond Stadial (= Younger Dryas) glaciation are of Lateglacial (pre‐Holocene) age; and (3) numerous RSFs must also have occurred inside Loch Lomond Stadial (LLS) glacial limits, but that runout debris was removed by LLS glaciers. Copyright © 2013 John Wiley & Sons, Ltd.     

Some analyses and numerical simulations of meiyu in east asia in 1983

In this paper the differences between Meiyu and Baiu front in 1983 have firstly been analysed, the trajectories of air on and to the north side of Meiyu and Baiu fronts during the Meiyu period have then been traced, and the fore-casting and simulating of 4 sets of Meiyu onset of the year have finally been run utilizing the global model at UK Me-teorological Office. The results show: 1) Meiyu fronts are different from Baiu ones in temperature, humidity and stratification fields in lower atmosphere; and the possibly reasons for it are explained. 2) The Bay of Bengal is the main moisture source for Meiyu front, the South China Sea and the Pacific, for Baiu ones; and some existed argu-ments on it are also discussed. 3) The onset of Meiyu and its rainfall and rain belts are sensitive to the Tibetan Plateau, and the water vapour conditions over the Bay of Bengal and the South China Sea, but not sensitive to the SST over the equatorial area or to the East of Japan.     

Possible usage of carbamide tar for creating artificial grounds with high sorption capacity

Filtering a lead solution through model samples prepared on the basis of alluvial sand mixed with carbamide tar at the ratio of 1: 1 and 1: 2 resulted in a sorption capacity of 30 and 160 mg/g of sample, respectively. Direct and reverse potentiometric titration of carbamide tar with a 0.1 N Pb (NO₃)₂ solution showed that these results are due to the fact that the curing of carbamide tar in acidic conditions is accompanied by irreversible lead sorption, which is not extracted by conventional buffer solutions. Thus, lead atoms become tightly integrated in the polymer structure of the tar with N-Pb-N bonding.     

Review of nekton patterns and ecological processes in seagrass landscapes

We reviewed seagrass landscape studies on nekton (fish and larger mobile crustaceans) to summarise: (1) patterns of nekton abundance in relation to patch attributes; and (2) models used to explain processes underpinning observed patterns. The response of nekton to landscape attributes is highly variable. Different taxa showed increasing densities with: increasing and decreasing patch size (12 and 11 taxa, respectively), increasing and decreasing proximity within a patch to edge (9, 14), increasing and decreasing distances from nearest seagrass patch (4, 11), and with patches perpendicular and parallel to currents (1, 2). The majority of taxa (213 out of 281, or 82%) showed no relationships. Landscape scale patterns are important for some species but evidence so far does not demonstrate major landscape effects overall. The lack of pattern might reflect the overriding importance of other factors such as within-patch characteristics, water depth or position within an estuary. It might also result from measurements at the wrong scale. The rigour of surveys can be improved by avoiding confounding of patch attributes by other factors, increasing awareness of statistical power, and more considered survey designs for attributes such as edge effects. The predation model is the most frequently invoked and tested model. Other explanatory models are based on disturbance, rates of encounter, food availability, larval supply, migration and reproductive success, but in many cases are not based on observed patterns. The best experimental work has been done on nekton species for which landscape studies have been built on a detailed understanding of the ecology of the species, such as for blue crabs (Callinectes sapidus). As this basic ecological platform is laid for more species, the landscape approach will become increasingly fruitful.