bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rational function model for sensor orientation of IRS‐P6 LISS‐4 imagery
Authors: Nagasubramanian V. , Radhadevi P. V. , Ramachandran R. , Krishnan R. 
Published: July 2010

AbstractThis paper explores the application of a rational function model (RFM) as a replacement sensor model for IRS‐P6 LISS‐4 imagery. The rational polynomial coefficients (RPCs), initially generated using a rigorous sensor model (RSM) through direct georeferencing, are bias‐compensated with a minimum number of ground control points and are used for various photogrammetric applications such as digital elevation model and ortho‐image generation. The performance of RFM and RSM is compared in the sensor modelling of LISS‐4 imagery over long strips. Results show that accuracies achieved using RFM are within 1 pixel (worst case) of the accuracies derived using RSM. Error variation as a function of the number of quasi‐control points (anchor points) used for RFM fitting as well as model errors with respect to the length of the image strip are analysed. System‐level accuracy does not deteriorate when the RFM is fitted up to a length of 1200 km. Absolute positioning accuracy of 1·5 pixels (∼9 m) is achieved from bias‐compensated RPCs. The results demonstrate the potential of RFM as a replacement sensor model. This allows standardisation of product generation packages to handle multiple sensors.
A sub‐pixel location method for interest points by means of the Harris interest strength
Authors: Zhu Qing , Wu Bo , Wan Neng 
Published: July 2010

AbstractThe sub‐pixel location of interest points is one of the most important tasks in refined image‐based 3D reconstruction in digital photogrammetry. The interest point detectors based on the Harris principles are generally used for stereoscopic image matching and subsequent 3D reconstruction. However, the locations of the interest points detected in this way can only be obtained to 1 pixel accuracy. The Harris detector has the following characteristics: (1) the Harris interest strength, which denotes the distinctiveness of an interest point, is a grey scale descriptor which computes the gradient at each sample point in a region around the point, and (2) the Harris interest strengths of the pixels in a template window centred on the interest point exhibit an approximately paraboloid distribution. This paper proposes a precise location method to improve the precision of the interest points on the basis of these characteristics of the Harris interest strength. Firstly, a least squares fit of a paraboloid function to the image grey scale surface using the Harris interest strength is designed in a template window and a Gaussian‐distance algorithm is employed to determine the weight. Then, the precise coordinates of this interest point are obtained by calculating the extremities of the fitting surface. The location accuracy of this method is studied both from the theoretical and the practical point of view. Experimental analysis is illustrated with synthetic images as well as actual images, which yielded a location accuracy of 0·15 pixels. Furthermore, experimental results also indicate that this method has the desired anti‐image‐noise and efficiency characteristics.
Molecular pathogenesis of hepatocellular carcinoma
Authors: Wong Chun‐Ming , Ng Irene O. L. 
Published: July 2010

AbstractHepatocellular carcinoma (HCC) is the fifth most common cancer and the third leading cause of cancer death worldwide. Hepatocarcinogenesis is a multistep process evolving from normal through chronic hepatitis/cirrhosis and dysplastic nodules to HCC. With advances in molecular methods, there is a growing understanding of the molecular mechanisms in hepatocarcinogenesis. Hepatocarcinogenesis is strongly linked to increases in allelic losses, chromosomal changes, gene mutations, epigenetic alterations and alterations in molecular cellular pathways. Some of these alterations are accompanied by a stepwise increase in the different pathological disease stages in hepatocarcinogenesis. Overall, a detailed understanding of the underlying molecular mechanisms involved in the progression of HCC is of fundamental importance to the development of effective prevention and treatment regimes for HCC.
A standard profile for Littorina transgressions in western Skåne, South Sweden
Authors: DIGERFELDT GUNNAR 
Published: July 2010

The investigation is based on diatem‐ and pollen analyses of a main profile from the ancient lagoon Barsebäcksmossen. The chronology is bared on C14‐‐dating.Seven transgressions are indicated, viz. 5200–4800 B.C., 4600–4400 R.C., 4150–3900 B.C., 3800–3700 B.C., 3600–3500 B.C., 3100–2950 H.C. and 2050–1850 B.C. Thc trangressions 4150–3900 B.C., 3800–3700 B.C. and 3600–3500 B.C. may only represent fluctuations during a ‘complex’ transgresssion. The transgresssion in Barsebäcksmtrssen are correlated with the transgresssion established by Berglund in the Baltic Sea and by Mörner in the Kattegatt sea.A change in the date of the pollen‐zone boundary AT 1/AT 2 from 4500–4600 B.C. to 5200 B.C. is proposed.
Palaeoecological study on the Holocene valley development of the River Main, southern Germany
Authors: BECKER BERND , SCHIRMER WOLFGANG 
Published: July 2010

Tree‐ring studies carried out on subfossil oak trunk deposits within the Holocene valley fills of the River Main can reconstruct phases of increased fluvial activities. These phases have been dated on the base of two absolutely tree‐ring dated chronologies and in addition by 11C‐datings of eleven floating tree‐ring scries of subfossil oaks.Geological‐pedological investigations reveal an alternation between increased and reduced fluvial activity during the Holocene.Periods of increased gravel redeposition are dated by dendrochronology, and by 14C and cultural findings. Increased fluvial activity becomes more frequent towards Modern Times with culminations in the Middle Atlantic, the Subboreal, the Iron‐Roman Age, the Main Middle Ages till earliest Modern Times, and in the last century.On the sequence of Holocene river deposits there developed specific soil types as indicators for the age of the river deposits since the Last Glacial.Among other palaeoecological results an important finding is the correlation between tree‐ring width, flood‐loam sedimentation, and soil development.
Some properties of Norwegian tills
Authors: JØKGENSEN PER 
Published: July 2010

Grain size distribution data for a large number of basal tills from different areas are presented. The Norwegian tills can be divided in two major groups: Tills derived from Precambrian bedrock and tills derived from Cambro‐Silurian sedimentary rocks. Both types are significantly different from Danish tills where unconsolidated sediments are incorporatcd. Chemical and mineralogical composition of the 125–250 μm fraction of tills derived from Precambrian rocks and tills derived from phyllites are presented. These data are used to determine transport distances for the till material.Due to a marked relief and short distances from the ice‐divides to the coast, the tills found in the Norwegian mountains have generally had a short transport and are, unless large amounts of unconsolidated sediments are incorporated, strongly influenced by the underlying bedrock.
Geochemistry of till in perennially frozen terrain of the Canadian shield— application to prospecting
Authors: SHILTS WILLIAM W. 
Published: July 2010

Shilts, W. W. 1977 06 01: Geochemistry of till in perennially frozen terrain of the Canadian shield ‐ application to prospecting.Geomorphological (drumlins, ribbed moraine) and geochemical features associated with till in the District of Keewatin are arranged in belts or dispersal trains paralleling the main direction of ice flow. Both types of features can be related to chemical and physical characteristics of specific types of source rocks.For dispersal studies in perennially frozen terrain, till samples were collected from mudboils at spacings of approximately 1.6 km. The texture of till samples varies significantly from sample site to sample site because of varying source‐rock lithologies and periglacial processes. Thus, because fractions coarser than clay are mostly quartz and feldspar and contain very little metal after weathering in the active layer, they were removed by centrifugation so as not to mask the ‘true’ relative metal contents of samples. The clay‐sized fraction was separated from till samples and analyzed on the assumption that it contained scavenging phases that adsorb cations in proportion to those released by weathering of mineralized particles that were originally physically dispersed by glacial action.Dispersal patterns of copper, zinc, nickel, and uranium were derived for approximately 1000 samples evenly distributed over a 2500 km2 grid. From these maps, large dispersal trains of copper and nickel were found, and known areas of high potential for uranium and Cu‐Zn mineralization were clearly indicated.
Sequence of till deposition and erosion in drumlins
Authors: WHITTECAR G. RICHARD , MICKELSON DAVID M. 
Published: July 2010

Whittecar, G.R. & Mickelson, D. M. 1977 06 01: Sequence of till deposition and erosion in drumlins.Extensive sand and gravel workings have exposed structural and compositional features of 17 gravel‐cored drumlins of late Wisconsin age in eastern Wisconsin. The drumlins are blanketed by 3 m of sandy basal till which truncates lower tills of earlier advanccs, outwash gravels, and an overlying till which is conformable to the gravel bedding and indistinguishable in composition from the surface till. Sands and gravels in the interior of some drumlins are deformed into large overturned folds, and into elastic dikes of fine sand and silt which penetrate to the top of the drumlin and warp overlying gravels. Both the folds and horizontal bedding are truncated by either the drumlin edge or the till blanket.We interpret the conformable, truncated, and in some cases folded, till as a basal till deposited during glacial advance. The capping, truncating till is viewed as a basal till left by retreating ice.The following sequence of events is suggested: (1) advance of ice over outwash, and deposition of till in a zone mar the margin; (2) thickening of the ice and erosion of the drumlin shapes; (3) local folding of the gravels and continued erosion; (4) retreat of ice and deposition of basal till under thin ice; (5) deposition of localized ablation till and stratified deposits.
Grain‐size distribution and grain‐size parameters of different till types on Hardangervidda, south Norway
Authors: VORREN TORE O. 
Published: July 2010

Vorren, T. O. 1977 06 01: Grain‐size distribution and grain‐size parameters of differcnt till type on Hardangervidda, south Norway.Grain‐size characteristics for different till types on Hardangervidda havc been studied: Basal tills are finer grained than ablation tills: phyllitic basal tills are relatively rich in gravel and clay: basal tills derived from a semiporphyritic granite are poor in clay and have a deficiency of very coarse sand. Of the Folk a Ward's (1957) grain‐size distribution parameters, sorting and kurtosis seem to he the most diagnostic parameters for distinguishing between different types of till. A linear corrclation betwen sorting and the other grain‐size parameters is indicated for the basal tills.
Avian predators as accumulators of fossil mammal material
Authors: MAYHEW DAVID F. 
Published: July 2010

Differences between the remains of mammalian prey in pellets of diurnal and nocturnal avian predators are discussed on the basis of recent material and in relation to probable fossil occurrences. The ability of diurnal predators to digest bone reduces the value of their pellets for quantitative or qualitative indications of the regional mammalian fauna. However, the remaining partially digested fragments in pellets of diurnal predators appear to have a characteristic morphology which may be recognised in a sample of fossil mammalian teeth from the type Cromerian Upper Freshwater Bed sediments at West Runton, England. The implications of such an origin for faunal analysis are briefly considered.This is believed to be the first time that the role of diurnal predatory birds in accumulation of fossil vertebrate material has been recognised. The characteristically digested teeth from diurnal predator pellets may provide the only direct indication of the origin of at least a part of the mammalian material contained in deposits formed in open sedimentary environments where skeletal parts have been dissociated.
The West Bornholm basin in the Baltic Sea: geological structure and Quaternary sediments
Authors: KÖGLER FRIEDRICH‐C. , LARSEN BIRGER 
Published: July 2010

KÖgler, F.‐C. & Larsen, B. 1979 03 01: The West Bornholm basin in the Baltic Sea: geological structure and Quaternary sediments. Boreas. Vol. 8, pp. 1–22. Oslo. ISSN 0300–9483.The West Bornholm basin is an approx. 1000 km2 subbasin of the Bornholm basin just north of Bornholm. The basin has been mapped by acoustic profiling and sampling of the sea floor. The basin is eroded down into Mesozoic sediments which are downfaulted between basement horsts in the Fennoscandian Border Zone. The development of the Quaternary morphology is illustrated by maps of the surface of the bedrock, the glacial landscape beneath the varved clays, the recent topography combined with isopach maps of late Glacial and Holocene formations. Quaternary formations are defined and described. The brown, very fine grained varved clay is deposited as a conformable cover on the substratum. It is probably deposited from suspensions carried in the whole water body, while turbidity currents were of minor importance. The recent sedimentary environment is an example of a restricted, but not totally anoxic basin. The recent sediment is chiefly mud rich in organic matter (ca. 4% Corg). According to a rough estimate, the long‐term mean sedimentation rate of organic carbon is 6 g/m2/year.
Brown earth and podzol: soil genesis illuminated by microfossil analysis
Authors: ANDERSEN SVEND TH. 
Published: July 2010

Andersen, S. Th. 1979 03 01: Brown earth and podzol: soil genesis illuminated by microfossil analysis. Boreas, Vol. 8, pp. 59–73. Oslo. ISSN 0300–9483.Pollen and other plant microfossils were studied in soil profiles from a Fagus‐Quercus petraea woodland in eastern Jutland, Denmark. Fungal hypha fragments in the soil show characteristic length frequency distributions, which indicate comminution by large arthropods and microarthropods (Oribatei) during the burial. Distribution of the hypha fragments within the podzol indicates development from a former brown earth. The pollen sequence in a humus deposit reflects recent vegetational development. Modification of pollen assemblages in the mineral soils can be explained by mixing during burial by soil fauna. Development from brown earth to podzoloid and podzol follows the models assumed by pedologists. The various stages are related to vegetational changes and the processes were completed within a few hundred years.
Genesis of the Sveg tills and Rogen moraines of central Sweden: a model of basal melt out
Authors: SHAW JOHN 
Published: July 2010

Shaw, John 1979 1201: Genesis of the Sveg tills and Rogen moraines of central Sweden: a model of basal melt out. Boreas, Vol. 8, pp. 409–426. Oslo. ISSN 0300–9483.Climatic amelioration in permafrozen regions causes basal melting of Polar glaciers. Supraglacial debris concentrated at the ice surface by ablation at first inhibits the ablation process. When the surface debris is equal in thickness to the active layer no further surface melting occurs. Till deposition processes in permafrozen areas are consequently dominated by melt out from a basal isothermal zone at melting point. The basal melt‐out process is influenced by englacial structures and forms which are also largely responsible for the resultant landforms and deposits. Such basal melt out may also occur in areas with less severe climate. A model for deposition largely by basal melt out is documented by field observations in central Sweden. Melt‐out tills in areas of former extending or uniform glacier flow show an upward facies change corresponding to poorly attenuated and highly attenuated englacial facies. The till facies are recognised in terms of stratigraphic position, surface form, internal structure, and clast lithology, size, shape, and long‐axis orientation and dip. Areas of former compressive flow are characterised by basal melt out of folded and dislocated englacial debris zones in which the stacking of debris produced transverse moraine ridges. The internal structure of the ridges includes folded till bodies dislocated by thrust planes, horizontal, stratified layers cross‐cutting the tectonic structures, and characteristic distributions of clast long‐axis orientation and dip. The morphology of the ridges at both the macro and micro scales is in accord with the proposed model of formation. The morphological and sedimentological associations produced largely by basal melt out are summarized. An additional implication of the proposed model is that gradual lowering of the supraglacial sediment surface by bottom melting of regionally stagnant ice may be the cause of widespread marine or lacustrine transgression.
Dendroclimatic studies on conifers from central Europe and Great Britain
Authors: SCHWEINGRUBER FRITZ H. , BRÄKER OTTO U. , SCHÄR ERNST 
Published: July 2010

Schweingruber, Fritz H., BrÄker, Otto U. & SchÄr, Ernst 1979 1201: Dendroclimatic studies on conifers from central Europe and Great Britain. Boreas, Vol. 8, pp. 427–452. Oslo. ISSN 0300–9483.The use of X‐ray densitometry for measuring tree rings makes it possible to consider the relations between climate and tree rings in a new light. Investigations so far have shown that it is the maximum density of the annual rings that provides the most important and best climatological information. Comparisons between density sequences are possible when the tree‐ring samples come from ecologically similar sites. Site characteristics are expressed by six different tree‐ring parameters. Relations between the maximum densities of various species from different regions are revealed by calculating the percentage of agreement. The growth rate of cell walls in latewood of all coniferous species from cool humid regions is limited mainly by summer temperatures. In Scotland, where the climate is cool‐oceanic and relatively stable, the cell walls grow from June to October. In the subalpine zone of the Alps and the Rocky Mountains near the timber line growth takes place mainly in August and September. Maximum density in trees of temperate sites is also primarily influenced by the summer temperature. Minimum density shows the relationship to the xerothermic site characteristics. On dry sites cambial activity and cell wall growth in latewood are mainly limited by precipitation during the growth period.Samples from the subalpine zones (1500–2200 m above sea level) between latitudes 45d̀ and 50d̀ North, i.e. those from the Western Carpathians, the Alps, and the Northern Appalachian Mountains, seem to form a unity. Samples from the oceanic region (20–600 m above sea level) between 52d̀ and 58d̀N latitudes show a different and incoherent picture. Only the present low level density during 1950–1975 is evident at all sites investigated for the last 200 years.By cross‐dating the annual tree‐ring sequences of living trees with samples of timber taken from ancient houses a 700‐year‐long chronology has been developed for the Northern Prealps in Switzerland. This chronology shows the approximate annual and decennial temperature changes; the sensitivity curve shows the different climatic variability in temperature.
Geomorphology and palaeoecology of the Mark valley (southern Netherlands): geomorphological valley development during the Weichselian and Holocene
Authors: VANDENBERGHE JEF , BOHNCKE SJOERD , LAMMERS WIM , ZILVERBERG LIESBETH 
Published: July 2010

Vandenberghe, Jef, Bohncke, Sjoerd, Lammers, Wim & Zilverberg, Liesbeth 1987 03 01: Geomorphology and palaeoecology of the Mark valley (southern Netherlands): geomorphological valley development during the Weichselian and Holocene. Boreas, Vol. 16, pp. 55–67. Oslo. ISSN 0300–9483.The actual area of the Mark valley is limited by the borders of an Early Weichselian erosion phase. The subsequent accumulation has resulted in the formation of a Weichselian Pleniglacial terrace which has been deeply dissected by Late Glacial erosion. The present alluvial plain is formed by Late Glacial and Holocene infilling. The maximum incision of the Late Glacial fluvial phase was reached slightly before 11,780 B.P. and involved locally dry conditions which have given rise to aeolian activity during this period (Older Dryas). On the deepest parts of the Pleniglacial terrace, a backswamp environment was established until the end of the Alleröd. At the beginning of the Younger Dryas the river invaded the terrace but shortly afterwards aeolian activity progressively increased. At the climax of the Younger Dryas, deep seasonal frost or local permafrost characterized the Mark valley.
Geomorphology and palaeoecology of the Mark valley (southern Netherlands): palaeoecology, palaeohydrology and climate during the Weichselian Late Glacial
Authors: BOHNCKE SJOERD , VANDENBERGHE JEF , COOPE RUSSELL , REILING RUDO 
Published: July 2010

Bohncke, Sjoerd, Vandenberghe, Jef, Coope, Russell & Reiling, Rudo 1987 03 01: Geomorphology and palaeoecology of the Mark valley (southern Netherlands): palaeoecology, palaeohydrology and climate during the Weichselian Late Glacial. Boreas, Vol. 16, pp. 69–85. Oslo. ISSN 0300–9483.A backswamp peat, located on an Upper Pleniglacial terrace, has been analysed in detail with respect to its pollen content, its macroscopic plant remains and its fossil insect fauna. The analyses permitted a detailed reconstruction of the Late Glacial palaeoenvironment besides an estimation of fluctuations in the local humidity and fluctuations in the palaeotemperatures. The main boundaries in the sequence have been radiocarbon dated, indicating a peat accumulation from c.12,600 B.P. to 10,970 B.P. The Bölling s.l. shows a clear migration of vegetation belts, starting with a shrub vegetation and passing into a birch wood. This progressive vegetation development culminates in a short lasting Pinus maximum early in the Alleröd, without being hampered by events during the Older Dryas. Up to and including the Alleröd no serious climate deterioration is registered. The humidity curve reveals a semiterrestrial phase in the local hydrosere that correlates with the Older Dryas and that is explained by the geomorphological evolution of the adjacent river system. The transition to the Younger Dryas coincides with a return to fluvial conditions and a marked change in the pollen record and insect fauna, indicating a decline in the average July temperature from between 18 and 15°C to 11 and 10°C.
The prospects for establishing synchroneity in the early postglacial pollen peak ofJuniperusin the British Isles
Authors: TIPPING RICHARD M. 
Published: July 2010

Tipping, Richard M. 1987 06 01: The prospects for establishing synchroneity in the early postglacial pollen peak ofJuniperusin the British Isles.Boreas, Vol. 16, pp. 155–163. Oslo. ISSN 0300–9483.Seventy radiocarbon assays on the early postglacialJuniperuspollen peak in the British Isles are collated in order to test the hypothesis that the expansion ofJuniperuswas synchronous in the British Isles. The necessity of screening this data base is discussed, as are the screening procedures adopted. A number of problems concerned with screening are highlighted, which are related to the paucity of information available from which to assess the reliability of a date. The accepted radiocarbon dates are analysed by computer‐generated histograms. No clear pattern of synchroneity is found. The possibility of a diachronous distribution across the British Isles is examined. The methods employed in this study illustrate the problems of using large samples of radiocarbon dates, and exemplify the stringent procedures required in handling such data.