Xxth International Congress of Photogrammetry and Remote Sensing     

Paul R. T. Newby  Peter A. Woodsford  Jon P. Mills  David A. Holland  William Tompkinson  Adrian J. Holmes  Stuart Robson  Paul Aplin  Simon J. Buckley  Henny Mehner 《The Photogrammetric Record》2004,19(108):375-402

The XXth International Congress of Photogrammetry and Remote Sensing was held at the Istanbul Convention and Exhibition Centre (ICEC), Turkey, from 12th to 23rd July 2004. Reports are given on the Congress as a whole, including the General Assembly, some Technical Commission activities and the Congress Exhibition. Papers from the Congress are published in Volume XXXV of the International Archives of Photogrammetry, Remote Sensing and Spatial Information Sciences.  相似文献   

Geography and the Social Sciences in Australia: an opportunity lost?1     

Ron Johnston 《The Australian geographer》2006,37(2):279-284

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Three-dimensional seismic reflection investigation of the upper crustal Winagami sill complex of northwestern Alberta, Canada     

J. Kim Welford  Ron M. Clowes 《Geophysical Journal International》2006,166(1):155-169

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RXTE spectroscopy of GRS 1915+105     

Jochen Greiner  Ed H. Morgan  Ron A. Remillard 《New Astronomy Reviews》1998,42(9-10)

The galactic superluminal motion source GRS 1915+105 has been extensively observed with the RXTE satellite over the last two years. More than 250 RXTE pointings have been performed until mid-May 1998 with more than 1.5 Msec exposure time on roughly a weekly basis. Here we report on first results of our spectral analysis of a major part of these pointed RXTE observations. We establish the existence of at least 5 spectral components and present the changes of these components over the last two years.  相似文献   

Evidence for a poleward meridional flow on the sun     

Ken Topka  Ron Moore  Barry J. LaBonte  Robert Howard 《Solar physics》1982,79(2):231-245

We define for observational study two subsets of all polar zone filaments, which we call polemost filaments and polar filament bands. The behavior of the mean latitude of both the polemost filaments and the polar filament bands is examined and compared with the evolution of the polar magnetic field over an activity cycle as recently distilled by Howard and LaBonte (1981) from the past 13 years of Mt. Wilson full-disk magnetograms. The magnetic data reveal that the polar magnetic fields are built up and maintained by the episodic arrival of discrete f-polarity regions that originate in active region latitudes and subsequently drift to the poles. After leaving the active-region latitudes, these unipolar f-polarity regions do not spread equatorward even though there is less net flux equatorward; this indicates that the f-polarity regions are carried poleward by a meridional flow, rather than by diffusion. The polar zone filaments are an independent tracer which confirms both the episodic polar field formation and the meridional flow. We find:

1. The mean latitude of the polemost filaments tracks the boundary of the polar field cap and undergoes an equatorward dip during each arrival of additional polar field.
2. Polar filament bands track the boundary latitudes of the unipolar regions, drifting poleward with the regions at about 10 m s^-1.
3. The Mt. Wilson magnetic data, combined with a simple model calculation, show that the filament drift expected from diffusion alone would be slower than observed, and in some cases would be equatorward rather than poleward.
4. The observation that filaments drift poleward along with the magnetic regions shows that fields of both polarities are carried by the meridional flow, as would be expected, rather than only the f-polarity flux which dominates the strength. This leads to the prediction that in the mid-latitudes during intervals between the passage of f-polarity regions, both polarities are present in nearly equal amounts. This prediction is confirmed by the magnetic data.

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Interannual to multidecadal modes of Labrador climate variability inferred from tree rings   总被引：2，自引：0，他引：2  

R. D'Arrigo  B. Buckley  S. Kaplan  J. Woollett 《Climate Dynamics》2003,20(2-3):219-228

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Everywhere different? Globalisation and the impact of international migration on Sydney and Melbourne     

James Forrest  Michael Poulsen  Ron Johnston 《Geoforum》2003,34(4):499-510

Using a new approach to classifying migrant group concentrations, we test for evidence of the effects of globalisation, associated by some with ‘protopostmodernity’, on two Australian cities. Sydney is characterised as an emergent world city and a focus of ‘new economy’ activities. Melbourne is associated with ‘old economy’ activities, dominated by manufacturing. In the Australian context, the onset of globalisation also coincided with significant changes to immigration policy: the end of a ‘white Australia’ policy in the early 1970s in favour of a skills-based policy, regardless of race or ethnicity. We argue that the evidence of the spatial behaviour of ethnic groups for these two cities highlights the essential continuity of ethnic segregation and spatial assimilation processes in two cities where segregation levels and experience are fundamentally different from many overseas examples. We further argue for a need to recognise that context, and the ethnic experience, are everywhere different, both intra- and internationally.  相似文献   

Integrating geophysical and hydrochemical borehole-log measurements to characterize the Chalk aquifer, Berkshire, United Kingdom   总被引：1，自引：0，他引：1  

Marc Schürch  David Buckley 《Hydrogeology Journal》2002,10(6):610-627

Geophysical and hydrochemical borehole-logging techniques were integrated to characterize hydraulic and hydrogeochemical properties of the Chalk aquifer at boreholes in Berkshire, UK. The down-hole measurements were made to locate fissures in the chalk, their spatial extent between boreholes, and to determine the groundwater chemical quality of the water-bearing layers. The geophysical borehole logging methods used were caliper, focused resistivity, induction resistivity, gamma ray, fluid temperature, fluid electrical conductivity, impeller and heat-pulse flowmeter, together with borehole wall optical-imaging. A multiparameter data transmitter was used to measure groundwater temperature, electrical conductivity, dissolved oxygen, pH, and redox potential of the borehole fluid down-hole. High permeability developed at the Chalk Rock by groundwater circulation provides the major flow horizon at the Banterwick Barn study site and represents a conduit system that serves as an effective local hydraulic connection between the boreholes. The Chalk Rock includes several lithified solution-ridden layers, hardgrounds, which imply a gap in sedimentation possibly representing an unconformity. Lower groundwater temperature, high dissolved-oxygen content, and flowmeter evidence of preferential groundwater flow in the Chalk Rock indicated rapid groundwater circulation along this horizon. By repeating the logging at different times of the year under changing hydraulic conditions, other water-inflow horizons within the Chalk aquifer were recognized. Electronic Publication  相似文献   

Resistivity of partially saturated Triassic Sandstone   总被引：1，自引：0，他引：1  

Steve Taylor  Ron Barker 《Geophysical Prospecting》2002,50(6):603-613

The variation in resistivity with saturation of poorly cemented Triassic Sandstone samples from a site in the English Midlands has been measured. The measurements were obtained using an adapted four‐electrode technique, which utilizes conductive gelling agents between electrodes, avoiding the need to sputter electrodes directly on to samples – a difficult process with such friable samples. The measurements provide important information regarding the way in which resistivity varies with saturation in the Triassic Sandstone. The resulting variation in the observed resistivity versus saturation curves indicates the presence of significant pore‐scale variation between samples. Measurements have also been conducted on fully saturated samples. These indicate significant variation in the matrix conductivity between samples. The results have important implications for field‐scale monitoring of the unsaturated zone.  相似文献   

Example of a debris-flow risk analysis from Vancouver Island,British Columbia,Canada     

Ron Arksey  Doug VanDine 《Landslides》2008,5(1):121-126

In July 2005, a debris flow and a water flood occurred on two adjacent gullies in the White River area, on northern Vancouver Island in British Columbia, Canada. The 16,000 m³ debris flow buried approximately 7.5 ha of second-growth trees, buried approximately 500 m of a forestry road, and reached two fish-bearing streams. The water flood eroded approximately 240 m of the same forestry road and plugged four culverts before overtopping and inundating the road. To better plan for future events, risk analyses of debris flows, debris floods, and water floods were carried out for the two gullies involved, plus a third adjacent gully. The elements at risk that were analyzed included, in order of priority: users of the forestry road, the fish-bearing streams, the forestry road itself, and a timber bridge. Using a series of qualitative, but defined, relative-risk matrices, the following components of specific risk were estimated for each of the three types of events on each of the three gullies for each of the four elements at risk: probability of occurrence, probability that the event will reach or otherwise affect the site of the element at risk, the probability that the element at risk will be at the site when the event occurs, and the probability of loss or damage resulting from the element being at the site when the event occurs.  相似文献