Perception of urban retailing environments: An empirical analysis of consumer information and usage fields

This article reports on an empirical analysis of consumer information and usage fields in the city of Eindhoven. The main purposes of this study are to investigate the distance, sectoral and directional biases of these fields, to analyse whether the degree of biases is related to personal characteristics of consumers and to identify the factors of the basis on which a model which predicts the probability that a shopping centre will be known by consumers can be developed. The findings of the study suggest that strong distance, sectoral and directional biases are present in the information and usage fields of consumers and that no systematic relationships exist between these characteristics of information and usage fields and personal variables of consumers. Finally, the present studies suggests that a model which describes the formation of consumer choice sets should include spatial factors such as distance, size, intervening opportunities and direction towards the city centre.     

Periodicities in blue crab population of Chesapeake Bay

Analysis of the annual blue crab catch in Chesapeake Bay for the years 1922–1976 shows that there are variations with periods of 18.0, 10.7, and 8.6 years. Analysis of Philadelphia air temperatures shows periods of 17.5, 9.8, and 7.4 years. The periods of 18.0 and 17.5 years agree with the 18.6 year period of the Earth-Moon-Sun tidal force, and the periods of 8.6 and 7.4 years agree with the 8.8 year period of the Earth-Moon-Sun tidal force, within experimental error. The periods of 9.8 and 10.7 years, for the temperatures and crabs, respectively, are probably related to the 10.5 year sunspot cycle within experimental error.     

Late glacial and postglacial pollen and plant macrofossils from Lake West Okoboji, Northwestern Iowa

Pollen and plant macrofossils preserved in lake sediment from Lake West Okoboji, Dickinson County, Iowa, indicate how the vegetation of that area changed during the late glacial and postglacial. A closed coniferous forest, dominated by spruce and larch trees, produced the Picea-Larix pollen assemblage zone. Fir trees were a minor constituent of this forest; pine trees were probably absent. Black ash trees increased in abundance at Lake West Okoboji and by 13,500 yr ago were an important constituent of the forest. The sediment accumulation rate and the pollen influx were low throughout this time. Birch and alder pollen peaked in abundance approximately 11,800 yr ago. Pollen influx increased rapidly as birch and alder replaced coniferous trees on the uplands. A deciduous forest, containing abundant oak and elm trees, replaced the birch-alder-coniferous forest. This forest inhabited northwestern Iowa from approximately 11,000 to 9000 yr B.P. Nonarboreal species became prevalent between approximately 9000 and 7700 yr B.P. as prairie began to replace deciduous forest on the uplands. Charred remains of Amorpha canescens and other upland species attest to the presence of prairie fires as an aid in establishing prairie and destroying the forest. The pollen influx declined. The warmest, driest part of the postglacial occurred in northwestern Iowa from approximately 7700 to 3200 yr ago. Lake level fell 9 to 10 m, and prairie extended to the edge of the lake. Wet-ground weeds inhabited areas near lake level which were alternately flooded, then dry. Pollen influx was approximately 100 grains/cm²/yr during the driest time in this dry interval.Deciduous trees, particularly oaks, returned after approximately 3200 yr B.P. Prairie continued to occupy the uplands but trees were more common in the lowlying wet areas. Settlement by Europeans in northwestern Iowa about 1865 is marked by an increase in weed pollen. Macrofossil deposition changed in 1910 in response to the stabilization of lake level.     

Turbulence structure in temperature inversions and in convection fields as observed by doppler sodar

The structure of turbulence in an inversion layer and in an homogeneous convective field of the planetary boundary layer is described. In the first part of the paper, we validate the sodar estimates of turbulent dissipation, by using measurements with an hot-wire anemometric system in situ. Limitations of an ε measurement technique using structure function calculations are given, taking account of atmospheric properties and acoustic Doppler instrumental effects. By comparison between isopleths of backscattering intensity and of turbulent dissipation rates, we observe that in the early morning, turbulence is advected by mechanical turbulence generated by wind shear. The same mechanism seems to be operating in the case of an inversion layer capping thermal instability, when the convective activity is not too greatly developed. A turbulent kinetic energy budget is examined using aircraft, sodar, and tower measurements. This indicates a constant turbulent dissipation profile through a deep convective layer.     

Average winter temperatures at De Bilt (the Netherlands): 1634–1977

A very long series of average winter temperatures in the Netherlands is presented. The series is based on direct observations (1735–1977) and administrative data concerning Dutch canals (1634–1734). The sources and the reliability of the data are discussed. Some characteristics of the series are shown.     

TheoreticalPKP seismograms near the caustic calculated by sum of reflected waves

Summary This paper gives some examples of theoretical seismograms of PKP waves near the caustic. Seismograms of refracted waves for the original medium are compared with seismograms composed as a sum of the reflected waves, generated at boundaries of a substitute medium. All seismograms are calculated by zero approximation of the ray theory. The influence of some parameters of the source function and of the substitute medium on the results is shown.     

Driving forces of orogeny, with emphasis on blue-schist facies of metamorphism (test-case III: The Japan arc)

Blue-schists are the product of an eo-alpine metamorphic event in former trenches (foredeeps), under conditions of high confining pressures and relatively low temperatures. The metamorphic sedimentary rock sequences are generally associated with basic to ultra-basic rocks of the ophiolitic suite (and their metamorphic equivalents), both appearing in belts of partly plastically deformed, partly highly imbricated Pennine-type nappes.The metamorphism and tectonization of the foredeeps (trenches) with their sedimentary and igneous contents occurred during the overriding of major Austroalpine nappes from the concave (inner) side of the orogenic arcs. The foreland is passively subducted during this major orogenic phase (the ‘Flysch phase’ of Alpine-type orogeny).In those cases where the foreland is a continental lithosphere (such as the foreland of the Alpine belt in the Mediterranean) the subduction is less deep than in those cases where the “foreland” is formed by an oceanic lithosphere (such as in the case of the Japan arc).The geological setting of blue-schists in the Alpine system of the western Mediterranean shows that the load pressures produced by the Austroalpine nappes were generally lower than the confining pressures required by experimental data. Tectonic overpressures, produced during phases of high strain-rates which temporarily sealed off the pore fluids, may have produced the supplementary amount of confining pressure. An additional advantage of this hypothesis is, that it accounts for the occurrence of glaucophane-type metamorphism without such unusually low thermal gradients as those prognosticated by petrological experiments.Circum-Pacific blue-schist belts might be the result of deep subduction. However, the problem of rapid exhumation is then the stumbling block for the geodynamic model of plate-tectonics (Model I). The field data of observation do not confirm the expectation of this model, that subsequently dozens of kilometers of isostatic uplift occurred, exposing erosion levels from such great depths.On the other hand, the model of mantle-diapirism (Model II) suggests, that even if the trench deposits were subducted to great depths (passive subduction) upthrusting movements radiating from ‘Stockwerke’ of gravitational instability would drag up the high-P, low-T metamorphism immediately after its formation, in one and the same major phase of orogeny (flysch phase).The geological case-history of the Japan arc is analysed and its diagnostic facts are compared with the predictions (prognoses) of Model II. This verification leads to a confirmation of the functional correctness of this model of mantle-diapirism.A geodynamic analysis of the tectonic evolution and the present structural and geophysical situation of the Japanese realm leads to the conclusion that the driving forces of orogeny and seismicity are produced by stress-fields of gravitational instabilities that may occur in various structural levels (“Stockwerke”). These Stockwerke range in depth from near-surface to the top of the lower mantle, that is over a range about one thousand kilometers. This is a more complicated, but yet more realistic interpretation of the driving forces of orogeny, than the oversimplified views of plate-tectonics.