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Sample records for oligoryzomys longicaudatus spatial

  1. Hantavirus reservoir Oligoryzomys longicaudatus spatial distribution sensitivity to climate change scenarios in Argentine Patagonia

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    González Paula LM

    2009-07-01

    Full Text Available Abstract Background Oligoryzomys longicaudatus (colilargo is the rodent responsible for hantavirus pulmonary syndrome (HPS in Argentine Patagonia. In past decades (1967–1998, trends of precipitation reduction and surface air temperature increase have been observed in western Patagonia. We explore how the potential distribution of the hantavirus reservoir would change under different climate change scenarios based on the observed trends. Methods Four scenarios of potential climate change were constructed using temperature and precipitation changes observed in Argentine Patagonia between 1967 and 1998: Scenario 1 assumed no change in precipitation but a temperature trend as observed; scenario 2 assumed no changes in temperature but a precipitation trend as observed; Scenario 3 included changes in both temperature and precipitation trends as observed; Scenario 4 assumed changes in both temperature and precipitation trends as observed but doubled. We used a validated spatial distribution model of O. longicaudatus as a function of temperature and precipitation. From the model probability of the rodent presence was calculated for each scenario. Results If changes in precipitation follow previous trends, the probability of the colilargo presence would fall in the HPS transmission zone of northern Patagonia. If temperature and precipitation trends remain at current levels for 60 years or double in the future 30 years, the probability of the rodent presence and the associated total area of potential distribution would diminish throughout Patagonia; the areas of potential distribution for colilargos would shift eastwards. These results suggest that future changes in Patagonia climate may lower transmission risk through a reduction in the potential distribution of the rodent reservoir. Conclusion According to our model the rates of temperature and precipitation changes observed between 1967 and 1998 may produce significant changes in the rodent

  2. Glaciation Effects on the Phylogeographic Structure of Oligoryzomys longicaudatus (Rodentia: Sigmodontinae) in the Southern Andes

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    Eduardo Palma, R.; Dusan Boric-Bargetto; Fernando Torres-Pérez; Cristián E Hernández; Terry L. Yates

    2012-01-01

    The long-tailed pygmy rice rat Oligoryzomys longicaudatus (Sigmodontinae), the major reservoir of Hantavirus in Chile and Patagonian Argentina, is widely distributed in the Mediterranean, Temperate and Patagonian Forests of Chile, as well as in adjacent areas in southern Argentina. We used molecular data to evaluate the effects of the last glacial event on the phylogeographic structure of this species. We examined if historical Pleistocene events had affected genetic variation and spatial dis...

  3. Glaciation effects on the phylogeographic structure of Oligoryzomys longicaudatus (Rodentia: Sigmodontinae) in the southern Andes.

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    Palma, R Eduardo; Boric-Bargetto, Dusan; Torres-Pérez, Fernando; Hernández, Cristián E; Yates, Terry L

    2012-01-01

    The long-tailed pygmy rice rat Oligoryzomys longicaudatus (Sigmodontinae), the major reservoir of Hantavirus in Chile and Patagonian Argentina, is widely distributed in the Mediterranean, Temperate and Patagonian Forests of Chile, as well as in adjacent areas in southern Argentina. We used molecular data to evaluate the effects of the last glacial event on the phylogeographic structure of this species. We examined if historical Pleistocene events had affected genetic variation and spatial distribution of this species along its distributional range. We sampled 223 individuals representing 47 localities along the species range, and sequenced the hypervariable domain I of the mtDNA control region. Aligned sequences were analyzed using haplotype network, bayesian population structure and demographic analyses. Analysis of population structure and the haplotype network inferred three genetic clusters along the distribution of O. longicaudatus that mostly agreed with the three major ecogeographic regions in Chile: Mediterranean, Temperate Forests and Patagonian Forests. Bayesian Skyline Plots showed constant population sizes through time in all three clusters followed by an increase after and during the Last Glacial Maximum (LGM; between 26,000-13,000 years ago). Neutrality tests and the "g" parameter also suggest that populations of O. longicaudatus experienced demographic expansion across the species entire range. Past climate shifts have influenced population structure and lineage variation of O. longicaudatus. This species remained in refugia areas during Pleistocene times in southern Temperate Forests (and adjacent areas in Patagonia). From these refugia, O. longicaudatus experienced demographic expansions into Patagonian Forests and central Mediterranean Chile using glacial retreats.

  4. Glaciation effects on the phylogeographic structure of Oligoryzomys longicaudatus (Rodentia: Sigmodontinae in the southern Andes.

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    R Eduardo Palma

    Full Text Available The long-tailed pygmy rice rat Oligoryzomys longicaudatus (Sigmodontinae, the major reservoir of Hantavirus in Chile and Patagonian Argentina, is widely distributed in the Mediterranean, Temperate and Patagonian Forests of Chile, as well as in adjacent areas in southern Argentina. We used molecular data to evaluate the effects of the last glacial event on the phylogeographic structure of this species. We examined if historical Pleistocene events had affected genetic variation and spatial distribution of this species along its distributional range. We sampled 223 individuals representing 47 localities along the species range, and sequenced the hypervariable domain I of the mtDNA control region. Aligned sequences were analyzed using haplotype network, bayesian population structure and demographic analyses. Analysis of population structure and the haplotype network inferred three genetic clusters along the distribution of O. longicaudatus that mostly agreed with the three major ecogeographic regions in Chile: Mediterranean, Temperate Forests and Patagonian Forests. Bayesian Skyline Plots showed constant population sizes through time in all three clusters followed by an increase after and during the Last Glacial Maximum (LGM; between 26,000-13,000 years ago. Neutrality tests and the "g" parameter also suggest that populations of O. longicaudatus experienced demographic expansion across the species entire range. Past climate shifts have influenced population structure and lineage variation of O. longicaudatus. This species remained in refugia areas during Pleistocene times in southern Temperate Forests (and adjacent areas in Patagonia. From these refugia, O. longicaudatus experienced demographic expansions into Patagonian Forests and central Mediterranean Chile using glacial retreats.

  5. Modeling potential distribution of Oligoryzomys longicaudatus, the Andes virus (Genus: Hantavirus) reservoir, in Argentina.

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    Andreo, Verónica; Glass, Gregory; Shields, Timothy; Provensal, Cecilia; Polop, Jaime

    2011-09-01

    We constructed a model to predict the potential distribution of Oligoryzomys longicaudatus, the reservoir of Andes virus (Genus: Hantavirus), in Argentina. We developed an extensive database of occurrence records from published studies and our own surveys and compared two methods to model the probability of O. longicaudatus presence; logistic regression and MaxEnt algorithm. The environmental variables used were tree, grass and bare soil cover from MODIS imagery and, altitude and 19 bioclimatic variables from WorldClim database. The models performances were evaluated and compared both by threshold dependent and independent measures. The best models included tree and grass cover, mean diurnal temperature range, and precipitation of the warmest and coldest seasons. The potential distribution maps for O. longicaudatus predicted the highest occurrence probabilities along the Andes range, from 32°S and narrowing southwards. They also predicted high probabilities for the south-central area of Argentina, reaching the Atlantic coast. The Hantavirus Pulmonary Syndrome cases coincided with mean occurrence probabilities of 95 and 77% for logistic and MaxEnt models, respectively. HPS transmission zones in Argentine Patagonia matched the areas with the highest probability of presence. Therefore, colilargos presence probability may provide an approximate risk of transmission and act as an early tool to guide control and prevention plans.

  6. Range expansion of Oligoryzomys longicaudatus (Rodentia, Sigmodontinae in Patagonian Chile, and first record of Hantavirus in the region Ampliación del rango de distribución de Oligoryzomys longicaudatus (Rodentia, Sigmodontinae en la Patagonia de Chile y primer registro de Hantavirus en la región

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    SEBASTIÁN BELMAR-LUCERO

    2009-06-01

    Full Text Available At present, 20 species of Oligoryzomys (Rodentia, Sigmodontinae are recognized in the Neotropical region, most of them distinguished by their karyotypes, which fluctuates between 46-70 chromosomes. Two species are currently recognized in Chile, Oligoryzomys longicaudatus (Bennet, 1832; "colilargo" or the long-tailed pygmy rice rat; 2n = 56, which ranges from 27° to approximately 51° S, and O. magellanicus (Bennet, 1836; Magellanic pygmy rice rat; 2n = 54, south of 51° S in the Patagonian region of Chile and Argentina. As part of an ongoing research on the southern Patagonia of Chile, we report the results of small mammal samplings in six localities. We karyotyped 28 specimens and we also sequenced the hypervariable mtDNA region I in 22 individuals, aligning these sequences with an under development phylogeny of O. longicaudatus. We also evaluated the serology and viral charge in all captured specimens to detect the presence of antibodies to Andes virus (ANDV through Strip Immunoblot Assay (SIA, and of viral genome by RT-PCR. The results consistently showed that the karyotype of southern Patagonia specimens was 2n = 56, equal to that of O. longicaudatus, and that individuals from this area do not differentiate phylogenetically from those of the northern range of distribution. In addition, the serology showed the presence of antibodies IgG anti-ANDV and of viral genome in heart, kidney, spleen, and lungs of a single specimen of Oligoryzomys from the locality of Fuerte Bulnes in the Magallanes region. We conclude that all specimens trapped south of 51° S correspond to Oligoryzomys longicaudatus, thus expanding the distribution of this specie! from 51° to at least 55° S. The results also extended the disiribution of the Andes strain of Hantavirus to southernmost Patagonia.Actualmente se reconocen 20 especies de Oligoryzomys (Rodentia, Sigmodontinae en la región Neotropical, la mayoría de ellas distinguidas por sus cariotipos, los que fluct

  7. Spatial-Temporal Distribution of Hantavirus Rodent-Borne Infection by Oligoryzomys fulvescens in the Agua Buena Region--Panama.

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    Armién, Blas; Ortiz, Paulo Lazaro; Gonzalez, Publio; Cumbrera, Alberto; Rivero, Alina; Avila, Mario; Armién, Aníbal G; Koster, Frederick; Glass, Gregory

    2016-02-01

    Hotspot detection and characterization has played an increasing role in understanding the maintenance and transmission of zoonotic pathogens. Identifying the specific environmental factors (or their correlates) that influence reservoir host abundance help increase understanding of how pathogens are maintained in natural systems and are crucial to identifying disease risk. However, most recent studies are performed at macro-scale and describe broad temporal patterns of population abundances. Few have been conducted at a microscale over short time periods that better capture the dynamical patterns of key populations. These finer resolution studies may better define the likelihood of local pathogen persistence. This study characterizes the landscape distribution and spatio-temporal dynamics of Oligoryzomys fulvescens (O. fulvescens), an important mammalian reservoir in Central America. Information collected in a longitudinal study of rodent populations in the community of Agua Buena in Tonosí, Panama, between April 2006 and December 2009 was analyzed using non-spatial analyses (box plots) and explicit spatial statistical tests (correlograms, SADIE and LISA). A 90 node grid was built (raster format) to design a base map. The area between the nodes was 0.09 km(2) and the total study area was 6.43 km(2) (2.39 x 2.69 km). The temporal assessment dataset was divided into four periods for each year studied: the dry season, rainy season, and two months-long transitions between seasons (the months of April and December). There were heterogeneous patterns in the population densities and degrees of dispersion of O. fulvescens that varied across seasons and among years. The species typically was locally absent during the late transitional months of the season, and re-established locally in subsequent years. These populations re-occurred in the same area during the first three years but subsequently re-established further south in the final year of the study. Spatial

  8. Spatial-Temporal Distribution of Hantavirus Rodent-Borne Infection by Oligoryzomys fulvescens in the Agua Buena Region - Panama

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    Gonzalez, Publio; Cumbrera, Alberto; Rivero, Alina; Avila, Mario; Armién, Aníbal G.; Koster, Frederick; Glass, Gregory

    2016-01-01

    Background Hotspot detection and characterization has played an increasing role in understanding the maintenance and transmission of zoonotic pathogens. Identifying the specific environmental factors (or their correlates) that influence reservoir host abundance help increase understanding of how pathogens are maintained in natural systems and are crucial to identifying disease risk. However, most recent studies are performed at macro-scale and describe broad temporal patterns of population abundances. Few have been conducted at a microscale over short time periods that better capture the dynamical patterns of key populations. These finer resolution studies may better define the likelihood of local pathogen persistence. This study characterizes the landscape distribution and spatio-temporal dynamics of Oligoryzomys fulvescens (O. fulvescens), an important mammalian reservoir in Central America. Methods Information collected in a longitudinal study of rodent populations in the community of Agua Buena in Tonosí, Panama, between April 2006 and December 2009 was analyzed using non-spatial analyses (box plots) and explicit spatial statistical tests (correlograms, SADIE and LISA). A 90 node grid was built (raster format) to design a base map. The area between the nodes was 0.09 km2 and the total study area was 6.43 km2 (2.39 x 2.69 km). The temporal assessment dataset was divided into four periods for each year studied: the dry season, rainy season, and two months-long transitions between seasons (the months of April and December). Results There were heterogeneous patterns in the population densities and degrees of dispersion of O. fulvescens that varied across seasons and among years. The species typically was locally absent during the late transitional months of the season, and re-established locally in subsequent years. These populations re-occurred in the same area during the first three years but subsequently re-established further south in the final year of the

  9. Characterization of Juquitiba Virus in Oligoryzomys fornesi from Brazilian Cerrado

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    Alexandro Guterres

    2014-03-01

    Full Text Available The Juquitiba virus, an agent of Hantavirus Cardiopulmonary Syndrome, is one of the most widely distributed hantavirus found in South America. It has been detected in Oligoryzomys nigripes, Akodon montensis, Oxymycterus judex, Akodon paranaensis in Brazil and in O. nigripes, Oryzomys sp. and Oligoryzomys fornesi rodents in Argentine, Paraguay and Uruguay. Here, we report the genomic characterization of the complete S segment from the Juquitiba strain, isolated from the lung tissues of O. fornesi, the presumed rodent reservoir of Anajatuba virus in Brazilian Amazon, captured in the Cerrado Biome, Brazil.

  10. Extraction Efficiency of Belonolaimus longicaudatus from Sandy Soil.

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    McSorley, R; Frederick, J J

    1991-10-01

    Numbers of Belonolaimus longicaudatus extracted from sandy soils (91-92% sand) by sieving and centrifugation were only 40-55% of those extracted by sieving and incubation on a Baermann tray. Residues normally discarded at each step of the sieving plus Baermann tray extraction procedure were examined for nematodes to obtain estimates of extraction efficiencies. For third-stage and fourth-stage juveniles, males, and females, estimates of extraction efficiency ranged from 60 to 65% in one experiment and 73 to 82% in another. Estimated extraction efficiencies for second-stage juveniles were lower (33% in one experiment, 67% in another) due to losses during sieving. When sterilized soil was seeded with known numbers of B. longicaudatus, 60% of second-stage juveniles and 68-76% of other stages were recovered. Most stages of B. longicaudatus could be extracted from these soils by sieving plus Baermann incubation with an efficiency of 60-70%.

  11. Comparative chromosome painting in six species of Oligoryzomys (Rodentia, Sigmodontinae and the karyotype evolution of the genus.

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    Camilla Bruno Di-Nizo

    Full Text Available Oligoryzomys belongs to the tribe Oryzomyini, and contains about 22 species. Diploid numbers range from 2n = 44 in Oligoryzomys sp. 2 to 2n = 72 in O. utiaritensis and phylogenetic relationships are not well defined. The high morphological convergence leads to misidentification of taxonomic entities and the species are often identified by chromosomal characters. Until now, the genus has been studied only by classical cytogenetic approaches. To understand the chromosomal evolution of Oligoryzomys, we developed chromosome probes from a female of Oligoryzomys moojeni (OMO with 2n = 70 and hybridized to other five Oligoryzomys species. The probes painted 31 segments on O. fornesi (OFO with 2n = 62; 32 segments on O. microtis (OMI, 2n = 64; 33 segments on O. nigripes (ONI, 2n = 62 and on O. rupestris (ORU, 2n = 46; and 34 on Oligoryzomys sp. 2 (OSP, 2n = 44. OMO probes 4 and 5 showed a syntenic association in O. fornesi, O. microtis and O. nigripes and were also presented in the same pair, although disrupted, in O. rupestris and Oligoryzomys sp. 2. Concerning O. rupestris and Oligoryzomys sp. 2, species with the lowest diploid numbers of the genus, a total of 8 probes hybridized to 11 segments on the largest pair of ORU 1 and 9 probes hybridized to 12 segments on OSP 1. Also, OMO 6 painted three segments in ORU, corresponding to the proximal segment of ORU 2q, and the whole of ORU 19 and 20. In OSP, the segment corresponding to ORU 20 was homologous to OSP 1p. OMO X showed signals of hybridization in both X and Y chromosomes. Extensive chromosomal rearrangements, that could not be detected by classical cytogenetic techniques, such as pericentric inversions or repositioning of centromeres, Robertsonian rearrangements and tandem fusions/fissions, as well as gain/activation or loss/inactivation of centromeres and telomeric sequences have driven the huge genome reshuffling in these closely related species.

  12. Comparative chromosome painting in six species of Oligoryzomys (Rodentia, Sigmodontinae) and the karyotype evolution of the genus.

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    Di-Nizo, Camilla Bruno; Ventura, Karen; Ferguson-Smith, Malcolm Andrew; O'Brien, Patricia Caroline Mary; Yonenaga-Yassuda, Yatiyo; Silva, Maria José de J

    2015-01-01

    Oligoryzomys belongs to the tribe Oryzomyini, and contains about 22 species. Diploid numbers range from 2n = 44 in Oligoryzomys sp. 2 to 2n = 72 in O. utiaritensis and phylogenetic relationships are not well defined. The high morphological convergence leads to misidentification of taxonomic entities and the species are often identified by chromosomal characters. Until now, the genus has been studied only by classical cytogenetic approaches. To understand the chromosomal evolution of Oligoryzomys, we developed chromosome probes from a female of Oligoryzomys moojeni (OMO) with 2n = 70 and hybridized to other five Oligoryzomys species. The probes painted 31 segments on O. fornesi (OFO) with 2n = 62; 32 segments on O. microtis (OMI), 2n = 64; 33 segments on O. nigripes (ONI), 2n = 62 and on O. rupestris (ORU), 2n = 46; and 34 on Oligoryzomys sp. 2 (OSP), 2n = 44. OMO probes 4 and 5 showed a syntenic association in O. fornesi, O. microtis and O. nigripes and were also presented in the same pair, although disrupted, in O. rupestris and Oligoryzomys sp. 2. Concerning O. rupestris and Oligoryzomys sp. 2, species with the lowest diploid numbers of the genus, a total of 8 probes hybridized to 11 segments on the largest pair of ORU 1 and 9 probes hybridized to 12 segments on OSP 1. Also, OMO 6 painted three segments in ORU, corresponding to the proximal segment of ORU 2q, and the whole of ORU 19 and 20. In OSP, the segment corresponding to ORU 20 was homologous to OSP 1p. OMO X showed signals of hybridization in both X and Y chromosomes. Extensive chromosomal rearrangements, that could not be detected by classical cytogenetic techniques, such as pericentric inversions or repositioning of centromeres, Robertsonian rearrangements and tandem fusions/fissions, as well as gain/activation or loss/inactivation of centromeres and telomeric sequences have driven the huge genome reshuffling in these closely related species.

  13. Transcriptome Analysis of the Tadpole Shrimp (Triops longicaudatus by Illumina Paired-End Sequencing: Assembly, Annotation, and Marker Discovery

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    Jiyeon Seong

    2016-12-01

    Full Text Available The tadpole shrimp (Triops longicaudatus is an aquatic crustacean that helps control pest populations. It inhabits freshwater ponds and pools and has been described as a living fossil. T. longicaudatus was officially declared an endangered species South Korea in 2005; however, through subsequent protection and conservation management, it was removed from the endangered species list in 2012. The limited number of available genetic resources on T. longicaudatus makes it difficult to obtain valuable genetic information for marker-aided selection programs. In this study, whole-transcriptome sequencing of T. longicaudatus generated 39.74 GB of clean data and a total of 269,822 contigs using the Illumina HiSeq 2500 platform. After clustering, a total of 208,813 unigenes with an N50 length of 1089 bp were generated. A total of 95,105 unigenes were successfully annotated against Protostome (PANM, Unigene, Eukaryotic Orthologous Groups (KOG, Gene Ontology (GO and Kyoto Encyclopedia of Genes and Genomes (KEGG databases using BLASTX with a cut-off of 1E−5. A total of 57,731 unigenes were assigned to GO terms, and 7247 unigenes were mapped to 129 KEGG pathways. Furthermore, 1595 simple sequence repeats (SSRs were detected from the unigenes with 1387 potential SSR markers. This is the first report of high-throughput transcriptome analysis of T. longicaudatus, and it provides valuable insights for genetic research and molecular-assisted breeding of this important species.

  14. Ontogenetic allometry in the foot size of Oligoryzomys flavescens (Waterhouse, 1837 (Rodentia, Sigmodontinae

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    R. Maestri

    Full Text Available Ontogenetic allometry is the study of how the size or shape of certain structures changes over the course of an animal’s development. In this study, using Huxley's formula of allometric growth (1932, we assessed the changes in the rate of growth of the feet size of the sigmodontine rodent Oligoryzomys flavescens during its ontogeny and compared differences between males and females. We find evidence of a change of polarity during the ontogenetic development of the species, with the presence of positive allometry during pregnancy and negative allometry in adulthood. Moreover, we note the presence of sexual dimorphism in the size of the feet, in which males of the species have a higher rate of growth than females. This growth pattern is positively related to escape from predators in childhood in both sexes and, in adulthood, provides a higher encounter rate of females by males, due to the larger displacement of the latter. We suggest that both the forces of natural selection and sexual selection have acted to shape the evolution of foot size in this species.

  15. Distribution and abundance of sigmodontine rodents in relation to hantavirus in Neuquén, Argentina.

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    Piudo, Luciana; Monteverde, Martín; González Capria, Silvana; Padula, Paula; Carmanchahi, Pablo

    2005-06-01

    In order to estimate spatial distribution, temporal variation, and prevalence of Andes hantavirus antibody in the rodent community, and especially in Oligoryzomys longicaudatus populations, four different ecosystems were trapped seasonally between spring 2001 and winter 2002 in Neuquen, northwestern Argentinean Patagonia. Five peridomestic settings were sampled within the same period. The rodent O. longicaudatus had the widest distribution in Neuquen, as it was the only species captured at every sample site except for the High Andean steppe, and it was also the most common species captured. Rodents of 13 species were tested for hantavirus antibody prevalence, but O. longicaudatus and Abrothrix longipilis were the only seropositive species. Seropositive individuals were captured during spring and summer in the Subantarctic forest and in winter 2001 in a peridomestic setting in the Patagonian steppe. The dominant presence of O. longicaudatus throughout Neuquen must be incorporated into strategies to prevent human exposure to hantavirus.

  16. A new species, Litomosoides odilae n. sp (Nematoda: Onchocercidae) from Oligoryzomys nigripes (Rodentia: Muridae) in the rainforest of Misiones, Argentina.

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    Notarnicola, Juliana; Navone, Graciela

    2002-10-01

    A new species of Litomosoides was collected from the abdominal cavity of Oligoryzomys nigripes (Rodentia: Muridae) in a semideciduous secondary rainforest of Misiones, Argentina. Litomosoides odilae n. sp. belongs to the carinii group and is characterized by the amphids displaced dorsally; buccal capsule with an anterior segment transparent and an annular asymmetrical thickening; esophagus divided, with the posterior glandular portion slightly wider than the muscular; male cloacal aperture strongly protruded; and microfilaria sheathed with an attenuated tail. The morphology of the new species, which is similar to that of L petteri, a parasite of marsupials in Brazil, suggests that host-switching events may have occurred in the diversification of this genus.

  17. Population Dynamics of Belonolaimus longicaudatus and Criconemella ornata and Growth Response of Bermudagrass and Overseeded Grasses on Golf Greens Following Treatment with Nematicides.

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    Lucas, L T

    1982-07-01

    Portions of a 'Tifgreen' bermudagrass golf green with poor turf and large numbers of Belonolabnus longicaudatus and Criconemella ornata were treated with selected nematicides in the summers of 1977 and 1978. Improvements in turf quality were observed within 4 wk after treatment with phenamiphos and fensulfothion. Treatment with phenamiphos restulted in lower numbers of B. longicaudatus 4 and 14 wk after treatment in the 1977 experiment and up to 1 yr after treatment in the 1978 experiment. Treatment with fensulfothion reduced the number of B. longicaudatus for only 1 month after treatment and significantly increased the numbers of this nematode in September and March in the 1978 experiment, Negative correlations were obtained between numbers of B. longicaudatus and turf qualily up to 1 yr. Numbers of C. ornata were reduced only in January and June following treatment with phenamiphos and not at any time with fensulfothion. Treatment with fensulfothion resulted in higher numbers of this nematode than in check plots in November and March. The percent area covered by prostrate spurge the following year was reduced following treatment with phenamiphos, but not with fensulfothion.

  18. The complete mitochondrial genome of lesser long-tailed Hamster Cricetulus longicaudatus (Milne-Edwards, 1867) and phylogenetic implications.

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    Zhang, Ziqi; Sun, Tong; Kang, Chunlan; Liu, Yang; Liu, Shaoying; Yue, Bisong; Zeng, Tao

    2016-01-01

    The complete mitochondrial genome sequence of Cricetulus longicaudatus (Rodentia Cricetidae: Cricetinae) was determined and was deposited in GenBank (GenBank accession no. KM067270). The mitochondrial genome of C. longicaudatus was 16,302 bp in length and contained 13 protein-coding genes, 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes and one control region, with an identical order to that of other rodents' mitochondrial genomes. The phylogenetic analysis was performed with Bayesian inference based on the concatenated nucleotide sequence of 12 protein-coding genes on the heavy strand. The result showed that these species from Cricetidae and its two subfamilies (Cricetinae and Arvicolines) formed solid monophyletic group, respectively. The Cricetulus had close phylogenetic relationship with Tscherskia among three genera (Cricetulus, Cricetulus and Mesocricetus). Neodon irene and Myodes regulus were embedded in Microtus and Eothenomys, respectively. The unusual phylogenetic positions of Neodon irene and Myodes regulus remain further study in the future.

  19. Ectoparasite occurrence associated with males and females of wild rodents Oligoryzomys flavescens (Waterhouse) and Akodon azarae (Fischer) (Rodentia: Cricetidae: Sigmodontinae) in the Punta Lara wetlands, Argentina.

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    Lareschi, Marcela

    2010-01-01

    The objective of this research was to study infestation parameters and indexes of ectoparasites associated with each sex of the wild rodents Oligoryzomys flavescens (Waterhouse) andAkodon azarae (Fischer) in the Punta Lara wetlands, Argentina. A trend towards higher mean abundance (MA) and ectoparasite specific richness was observed in males of O. flavescens whereas those values were similar for both A. azarae sexes. The prevalence of the following ectoparasites was significantly higher on males (Prodent hosts, these results are epidemiologically important.

  20. Comparison between Oligoryzomys nigripes and O. flavescens by RAPD and genetic diversity in O. nigripes (Rodentia, Cricetidae

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    AJ Mossi

    Full Text Available The genus of Oligoryzomys includes species of small size, morphologically similar, which may impede taxonomic identification, mainly between O. flavescens (Waterhouse, 1837 and O. nigripes (Olfers, 1818. The main objective of this work was to investigate whether the RAPD markers are capable of genetically differentiating the specimens O. nigripes and O. flavescens, coming from Rio Grande do Sul (RS and Santa Catarina (SC states, and also to estimate the genetic variability among populations of O. nigripes, with the Uruguay River as a geographical barrier. For this purpose, samples were collected in fragments of forests situated in the North of RS, at FLONA (Floresta Nacional de Passo Fundo and in fragments from SC, close to the Uruguay River. The karyotyping of two samples for each species was carried out and compared using the RAPD technique together with non- karyotyped individuals. Samples of O. nigripes presented 2n = 62; NA = 82, with submetacentric arms on the largest chromosomes, while samples of O. flavescens showed 2n = 64; NA = 66, with the largest chromosomes presenting acrocentric morphology, making such a result the main difference between the species. The analysis was able to detect two distinct groups, being the first one with karyotyped O. flavescens and the second with karyotyped O. nigripes. Identification afforded 211 loci, among them 181 (85.78% polymorphic. The Jaccard similarity coefficient was in the range of 0.45 to 0.87. The UPGMA and Main Coordinate Analysis techniques demonstrated the existence of heterogeneous genetics among populations, but did not separate them completely in terms of geographical standards, and they are not influenced by the Uruguay River, which did not act as an efficient barrier.

  1. Anatomia comparada e morfometria de oligoryzomys nigripes e o. flavescens (rodentia, sigmodontinae no Rio Grande do Sul, Brasil

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    Leonardo F. Machado

    2011-01-01

    Full Text Available Oligoryzomys nigripes e O. flavescens são amplamente distribuídos e simpátricos em diversos biomas. Os caracteres diagnósticos para seus reconhecimentos não são claramente estabelecidos. Neste estudo, foram realizadas a descrição e comparação da morfologia externa, anatomia do crânio, dentes, esqueleto pós crânio, morfologia estomacal e peniana. Análises estatísticas foram geradas a partir de dados morfométricos. A amostra consiste de 208 exemplares provenientes de 24 localidades do Brasil. O. nigripes é maior, com pelagem dorsal mais escura e pelagem ventral esbranquiçada e salpicada de preto. Crânio maior e mais robusto que O. flavescens. O. flavescens é menor, com pelagem dorsal levemente mais clara e ventre amarelado. O padrão de circulação cefálica das duas espécies é derivada de segundo tipo. Em O. flavescens são visualizados acidentes proeminentes na escápula e úmero, enquanto O. nigripes demonstrou maiores diferenças localizadas na crista íliaca, orientação do ísquio e acidentes proeminentes na tíbia e fíbula. A morfologia estomacal de ambos os táxons possui padrão Unilocular-hemiglandular. A morfologia do pênis consiste de báculo central tri-digitado. A análise de função discriminante reconhecem claramente a distinção de dois grupos homogêneos representados pelas espécies. Segundo o teste t duas variáveis morfométricas (largura da placa zigomática e largura do primeiro molar superior não são relevantes (P > 0.05 para a discriminação dos táxons. Dimorfismo sexual baseado na morfometria foi sustentado pelo teste t para O. nigripes. Em O. flavescens esta condição não é estatisticamente verificada.

  2. Andes virus infections in the rodent reservoir and in humans vary across contrasting landscapes in Chile

    Science.gov (United States)

    Torres-Pérez, Fernando; Palma, R. Eduardo; Hjelle, Brian; Ferres, Marcela; Cook, Joseph A.

    2009-01-01

    Hantavirus cardiopulmonary syndrome (HCPS) is an emerging infectious disease first reported in Chile in 1995. Andes hantavirus (ANDV) is responsible for the more than 500 cases of HCPS reported in Chile. Previous work showed that ANDV is genetically differentiated in Chile across contrasting landscapes. To determine whether the reservoir rodent (Oligoryzomys longicaudatus) populations are also geographically segregated, we conducted range-wide spatial genetic analyses of O. longicaudatus in Chile using the mitochondrial DNA cytochrome b gene. Given that landscape structure influences the incidence of hantavirus infections, we also tested 772 O. longicaudatus specimens for antibodies to ANDV captured during the period 2000 − 2006. Population genetic analyses of O. longicaudatus are largely congruent with those reported for ANDV, with the host primarily differentiated according to three defined ecoregions, Mediterranean, Valdivian rain forest and North Patagonian rain forest. Significant differences in the relative prevalence of anti-ANDV antibodies in rodent samples also were found across the three ecoregions. We relate these results to the number of reported human HCPS cases in Chile, and discuss the importance of landscape differences in light of ANDV transmission to humans and among rodent populations. PMID:19632357

  3. Rapid enzyme-linked immunosorbent assay for the detection of hantavirus-specific antibodies in divergent small mammals.

    Science.gov (United States)

    Cautivo, Karla; Schountz, Tony; Acuña-Retamar, Mariana; Ferrés, Marcela; Torres-Pérez, Fernando

    2014-05-06

    We assessed the utility of an enzyme-linked immunosorbent assay (ELISA) for the detection of hantavirus-specific antibodies from sera of Oligoryzomys longicaudatus, the principal reservoir of Andes virus (ANDV), using an antigen previously developed for detection of antibodies to Sin Nombre virus (SNV) in sera from Peromyscus maniculatus. The assay uses a protein A/G horseradish peroxidase conjugate and can be performed in as little as 1.5 hours. Serum samples from Oligoryzomys longicaudatus collected in central-south Chile were used and the assay identified several that were antibody positive. This assay can be used for the rapid detection of antibodies to divergent hantaviruses from geographically and phylogenetically distant rodent species.

  4. Rapid Enzyme-Linked Immunosorbent Assay for the Detection of Hantavirus-Specific Antibodies in Divergent Small Mammals

    Directory of Open Access Journals (Sweden)

    Karla Cautivo

    2014-05-01

    Full Text Available We assessed the utility of an enzyme-linked immunosorbent assay (ELISA for the detection of hantavirus-specific antibodies from sera of Oligoryzomys longicaudatus, the principal reservoir of Andes virus (ANDV, using an antigen previously developed for detection of antibodies to Sin Nombre virus (SNV in sera from Peromyscus maniculatus. The assay uses a protein A/G horseradish peroxidase conjugate and can be performed in as little as 1.5 hours. Serum samples from Oligoryzomys longicaudatus collected in central-south Chile were used and the assay identified several that were antibody positive. This assay can be used for the rapid detection of antibodies to divergent hantaviruses from geographically and phylogenetically distant rodent species.

  5. Spatial planning

    OpenAIRE

    Dimitrov, Nikola; Koteski, Cane

    2016-01-01

    The professional book ,, Space planning "processed chapters on: space, concept and definition of space, space as a system, spatial economics, economic essence of space, space planning, social determinants of spatial planning, spatial planning as a process, factors development and elements in spatial planning, methodology, components and content of spatial planning stages and types of preparation of spatial planning, spatial planning and industrialization, industrialization, urbanization and s...

  6. Spatial planning

    OpenAIRE

    Dimitrov, Nikola; Koteski, Cane

    2016-01-01

    The professional book ,, Space planning "processed chapters on: space, concept and definition of space, space as a system, spatial economics, economic essence of space, space planning, social determinants of spatial planning, spatial planning as a process, factors development and elements in spatial planning, methodology, components and content of spatial planning stages and types of preparation of spatial planning, spatial planning and industrialization, industrialization, urbanization and s...

  7. SPATIAL STABILITY

    OpenAIRE

    Pascal Mossay

    2004-01-01

    We consider a continuous spatial economy consisting of pure exchange local economies. Agents are allowed to change their location over time as a response to spatial utility differentials. These spatial adjustments toward higher utility neighborhoods lead the spatial economy to converge to a spatially uniform allocation of resources, provided that the matrix of price effects is quasi-negative definite. Furthermore our model provides a real time interpretation of the tâtonnement story. Also, sp...

  8. Spatial Databases

    Science.gov (United States)

    2007-09-19

    for a city . Spatial attributes are used to define the spatial location and extent of spatial objects [35]. The spatial attributes of a spatial object...regarding both geometry and thematic differentiation. It can be used to model 2.5D data (e.g., digital terrain model), as well as 3D data ( walkable ...within a city , if the coverage area of a wireless antenna is considered to be the visible area, then the union of coverage areas of all the antennas in

  9. Spatial cognition

    Science.gov (United States)

    Kaiser, Mary Kister; Remington, Roger

    1988-01-01

    Spatial cognition is the ability to reason about geometric relationships in the real (or a metaphorical) world based on one or more internal representations of those relationships. The study of spatial cognition is concerned with the representation of spatial knowledge, and our ability to manipulate these representations to solve spatial problems. Spatial cognition is utilized most critically when direct perceptual cues are absent or impoverished. Examples are provided of how human spatial cognitive abilities impact on three areas of space station operator performance: orientation, path planning, and data base management. A videotape provides demonstrations of relevant phenomena (e.g., the importance of orientation for recognition of complex, configural forms). The presentation is represented by abstract and overhead visuals only.

  10. Spatializing Time

    DEFF Research Database (Denmark)

    Thomsen, Bodil Marie Stavning

    2011-01-01

    The article analyses some of artist Søren Lose's photographic installations in which time, history and narration is reflected in the creation of allegoric, spatial relations.......The article analyses some of artist Søren Lose's photographic installations in which time, history and narration is reflected in the creation of allegoric, spatial relations....

  11. Spatializing Time

    DEFF Research Database (Denmark)

    2011-01-01

    The article analyses some of artist Søren Lose's photographic installations in which time, history and narration is reflected in the creation of allegoric, spatial relations.......The article analyses some of artist Søren Lose's photographic installations in which time, history and narration is reflected in the creation of allegoric, spatial relations....

  12. Spatial Culture

    DEFF Research Database (Denmark)

    2012-01-01

    – 2006. The essays published here allow us to subdivide the field of spatial culture into five major domains, summarized in the titles of chapters in the book: ”Perception and Strategies: Architecture”, ”Politics and Poetics: Urban Spaces”, ”Movements and Cityscape: Textuality”, ”Crisis and Construction......Spatial Culture – A Humanities Perspective Abstract of introductory essay by Henrik Reeh Secured by alliances between socio-political development and cultural practices, a new field of humanistic studies in spatial culture has developed since the 1990s. To focus on links between urban culture...... and modern society is, however, an intellectual practice which has a much longer history. Already in the 1980s, the debate on the modern and the postmodern cited Paris and Los Angeles as spatio-cultural illustrations of these major philosophical concepts. Earlier, in the history of critical studies, the work...

  13. Spatial Interpolation.

    NARCIS (Netherlands)

    Stein, A.

    1991-01-01

    The theory and practical application of techniques of statistical interpolation are studied in this thesis, and new developments in multivariate spatial interpolation and the design of sampling plans are discussed. Several applications to studies in soil science are presented.Sampling s

  14. Spatial distribution

    DEFF Research Database (Denmark)

    Borregaard, Michael Krabbe; Hendrichsen, Ditte Katrine; Nachman, Gøsta Støger

    2008-01-01

    Living organisms are distributed over the entire surface of the planet. The distribution of the individuals of each species is not random; on the contrary, they are strongly dependent on the biology and ecology of the species, and vary over different spatial scale. The structure of whole...... populations reflects the location and fragmentation pattern of the habitat types preferred by the species, and the complex dynamics of migration, colonization, and population growth taking place over the landscape. Within these, individuals are distributed among each other in regular or clumped patterns......, depending on the nature of intraspecific interactions between them: while the individuals of some species repel each other and partition the available area, others form groups of varying size, determined by the fitness of each group member. The spatial distribution pattern of individuals again strongly...

  15. The Spatial Politics of Spatial Representation

    DEFF Research Database (Denmark)

    Olesen, Kristian; Richardson, Tim

    2011-01-01

    This paper explores the interplay between the spatial politics of new governance landscapes and innovations in the use of spatial representations in planning. The central premise is that planning experiments with new relational approaches become enmeshed in spatial politics. The case of strategic...... spatial planning in Denmark reveals how fuzzy spatial representations and relational spatial concepts are being used to depoliticise strategic spatial planning processes and to camouflage spatial politics. The paper concludes that, while relational geography might play an important role in building...... consensus, it plays an equal important role in supporting current neoliberal transformations of strategic spatial planning....

  16. Hantavirus antibodies in rodents and human cases with pulmonary syndrome, Río Negro, Argentina Anticuerpos contra hantavirus en roedores y casos humanos con síndrome pulmonar, Río Negro, Argentina

    Directory of Open Access Journals (Sweden)

    Edmundo Larrieu

    2008-10-01

    Full Text Available In Río Negro Province, Argentina, human cases of hantavirus pulmonary syndrome (HPS appeared in the region of subantartic forests. The Andes virus (ANDV has been identified in the region both in Oligoryzomys longicaudatus rodents and in humans, with the main transmission being from rodents to humans but also showing the possibility of human to human transmission. Between 1996 and 2004, in 40 campaigns, 29.960 night-traps for capturing live rodents were set up. Blood samples were obtained from the rodents and processed using enzyme immunoassay with recombinant antigens made from ANDV. A total of 1767 rodents were captured, with a capture success of 5.9% and an antibody prevalence of 2.1%. Important differences were observed among the species captured from Andes and Steppe regions. Seropositive Oligoryzomys longicaudatus, Abrotrix olivaceus, Abrotrix xanhtothinus and Loxodontomus microtus were captured. During the 1993-2004 period, 40 HPS cases were registered.En la Provincia de Río Negro, Argentina, se presentaron casos humanos de síndrome pulmonar por hantavirus (SPH en la región de los bosques subantárticos. El virus Andes (AND fue identificado en la región, tanto en el roedor Oligoryzomys longicaudatus como en seres humanos, demostrándose la transmisión principalmente del roedor al hombre y la posibilidad de la transmisión de persona a persona. Para ello, se procedió a la colocación de 29.960 trampas para captura viva de roedores, tipo Sherman, en 40 operativos efectuados desde 1996 hasta 2004. Se obtuvieron muestras de sangre de los roedores, las que fueron procesadas mediante enzimoinmunoensayo con antígenos recombinantes elaborados a partir de virus AND. Fueron capturados 1767 roedores, con un éxito de trampeo del 5.9% y una prevalencia de anticuerpos contra hantavirus del 2.1%. Se observaron importantes diferencias en las especies capturadas en cada una de las regiones. Se capturaron O. longicaudatus, Abrothrix olivaceus y

  17. Handbook of Spatial Statistics

    CERN Document Server

    Gelfand, Alan E

    2010-01-01

    Offers an introduction detailing the evolution of the field of spatial statistics. This title focuses on the three main branches of spatial statistics: continuous spatial variation (point referenced data); discrete spatial variation, including lattice and areal unit data; and, spatial point patterns.

  18. Spatial Management Areas

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Spatial management files combine all related and relevant spatial management files into an integrated fisheries management file. Overlaps of the redundant spatial...

  19. Spatial econometrics using microdata

    CERN Document Server

    Dubé, Jean

    2014-01-01

    This book provides an introduction to spatial analyses concerning disaggregated (or micro) spatial data.Particular emphasis is put on spatial data compilation and the structuring of the connections between the observations. Descriptive analysis methods of spatial data are presented in order to identify and measure the spatial, global and local dependency.The authors then focus on autoregressive spatial models, to control the problem of spatial dependency between the residues of a basic linear statistical model, thereby contravening one of the basic hypotheses of the ordinary least squares appr

  20. Spatial Relation Resolution and Spatial Relation Abstraction

    Institute of Scientific and Technical Information of China (English)

    AI Tinghua; LIU Yaolin

    2003-01-01

    This paper attempts toregard spatial relation transformationas an important process in map gener-alization. The spatial relation generali-zation can be divided into the compo-nents of abstraction: topology, dis-tance and orientation. The concept‘ spatial relation resolution' is intro-duced to describe the constraints ofrelative spatial relation. On the basisof nine intersection models, the cardi-nal direction models and the iso-dis-tance-relation models, this paper givesthree sorts of relation resolution repre-sentations for topological, distance andorientation relation, respectively. Twomapping implementations in map gen-eralization is discussed.

  1. Spatial Data Management

    CERN Document Server

    Mamoulis, Nikos

    2011-01-01

    Spatial database management deals with the storage, indexing, and querying of data with spatial features, such as location and geometric extent. Many applications require the efficient management of spatial data, including Geographic Information Systems, Computer Aided Design, and Location Based Services. The goal of this book is to provide the reader with an overview of spatial data management technology, with an emphasis on indexing and search techniques. It first introduces spatial data models and queries and discusses the main issues of extending a database system to support spatial data.

  2. Spatial Language Learning

    Science.gov (United States)

    Fu, Zhengling

    2016-01-01

    Spatial language constitutes part of the basic fabric of language. Although languages may have the same number of terms to cover a set of spatial relations, they do not always do so in the same way. Spatial languages differ across languages quite radically, thus providing a real semantic challenge for second language learners. The essay first…

  3. Spatial Information Storage

    Directory of Open Access Journals (Sweden)

    Vladimir Markelov

    2013-01-01

    Full Text Available The article describes the spatial information storage, shows the features of spatial information and of such storage systems formation. Requirements for information storage technologies and for the data management in storage systems are determined. Cartographic information storage and updating features are shown. The article proves that intelligent solutions are the most efficient means of working with large amounts of spatial data.

  4. Memoz - Spatial Weblogging

    Science.gov (United States)

    Hoem, Jon

    The article argues that spatial webpublishing has influence on weblogging, and calls for a revision of the current weblog definition. The weblog genre should be able to incorporate spatial representation, not only the sequential ordering of articles. The article show examples of different spatial forms, including material produced in Memoz (MEMory OrganiZer).

  5. ABUJA SUSTAINABLE SPATIAL HOUSING DESIGN: A SPATIAL ...

    African Journals Online (AJOL)

    Bons

    2017-02-02

    Feb 2, 2017 ... the destitutes/homeless people in the city. The informal .... solving them, this research recommends retention and sustainable spatial integration of the ... Crisis, Planning, and the Quality of life: Managing the New Historical.

  6. Spatially-Heterodyned Holography

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Clarence E [Knoxville, TN; Hanson, Gregory R [Clinton, TN

    2006-02-21

    A method of recording a spatially low-frequency heterodyne hologram, including spatially heterodyne fringes for Fourier analysis, includes: splitting a laser beam into a reference beam and an object beam; interacting the object beam with an object; focusing the reference beam and the object beam at a focal plane of a digital recorder to form a spatially low-frequency heterodyne hologram including spatially heterodyne fringes for Fourier analysis; digital recording the spatially low-frequency heterodyne hologram; Fourier transforming axes of the recorded spatially low-frequency heterodyne hologram including spatially heterodyne fringes in Fourier space to sit on top of a heterodyne carrier frequency defined by an angle between the reference beam and the object beam; cutting off signals around an origin; and performing an inverse Fourier transform.

  7. Robustness of Spatial Micronetworks

    CERN Document Server

    McAndrew, Thomas C; Bagrow, James P

    2015-01-01

    Power lines, roadways, pipelines and other physical infrastructure are critical to modern society. These structures may be viewed as spatial networks where geographic distances play a role in the functionality and construction cost of links. Traditionally, studies of network robustness have primarily considered the connectedness of large, random networks. Yet for spatial infrastructure physical distances must also play a role in network robustness. Understanding the robustness of small spatial networks is particularly important with the increasing interest in microgrids, small-area distributed power grids that are well suited to using renewable energy resources. We study the random failures of links in small networks where functionality depends on both spatial distance and topological connectedness. By introducing a percolation model where the failure of each link is proportional to its spatial length, we find that, when failures depend on spatial distances, networks are more fragile than expected. Accounting...

  8. Comparing Spatial Predictions

    KAUST Repository

    Hering, Amanda S.

    2011-11-01

    Under a general loss function, we develop a hypothesis test to determine whether a significant difference in the spatial predictions produced by two competing models exists on average across the entire spatial domain of interest. The null hypothesis is that of no difference, and a spatial loss differential is created based on the observed data, the two sets of predictions, and the loss function chosen by the researcher. The test assumes only isotropy and short-range spatial dependence of the loss differential but does allow it to be non-Gaussian, non-zero-mean, and spatially correlated. Constant and nonconstant spatial trends in the loss differential are treated in two separate cases. Monte Carlo simulations illustrate the size and power properties of this test, and an example based on daily average wind speeds in Oklahoma is used for illustration. Supplemental results are available online. © 2011 American Statistical Association and the American Society for Qualitys.

  9. Moving Spatial Keyword Queries

    DEFF Research Database (Denmark)

    Wu, Dingming; Yiu, Man Lung; Jensen, Christian S.

    2013-01-01

    Web users and content are increasingly being geo-positioned. This development gives prominence to spatial keyword queries, which involve both the locations and textual descriptions of content. We study the efficient processing of continuously moving top-k spatial keyword (MkSK) queries over spatial...... text data. State-of-the-art solutions for moving queries employ safe zones that guarantee the validity of reported results as long as the user remains within the safe zone associated with a result. However, existing safe-zone methods focus solely on spatial locations and ignore text relevancy. We...

  10. Spatial electric load forecasting

    CERN Document Server

    Willis, H Lee

    2002-01-01

    Spatial Electric Load Forecasting Consumer Demand for Power and ReliabilityCoincidence and Load BehaviorLoad Curve and End-Use ModelingWeather and Electric LoadWeather Design Criteria and Forecast NormalizationSpatial Load Growth BehaviorSpatial Forecast Accuracy and Error MeasuresTrending MethodsSimulation Method: Basic ConceptsA Detailed Look at the Simulation MethodBasics of Computerized SimulationAnalytical Building Blocks for Spatial SimulationAdvanced Elements of Computerized SimulationHybrid Trending-Simulation MethodsAdvanced

  11. Spatial Keyword Querying

    DEFF Research Database (Denmark)

    Cao, Xin; Chen, Lisi; Cong, Gao;

    2012-01-01

    The web is increasingly being used by mobile users. In addition, it is increasingly becoming possible to accurately geo-position mobile users and web content. This development gives prominence to spatial web data management. Specifically, a spatial keyword query takes a user location and user-sup...... different kinds of functionality as well as the ideas underlying their definition....

  12. Computing with spatial trajectories

    CERN Document Server

    2011-01-01

    Covers the fundamentals and the state-of-the-art research inspired by the spatial trajectory data Readers are provided with tutorial-style chapters, case studies and references to other relevant research work This is the first book that presents the foundation dealing with spatial trajectories and state-of-the-art research and practices enabled by trajectories

  13. Spatial Data Analysis.

    Science.gov (United States)

    Banerjee, Sudipto

    2016-01-01

    With increasing accessibility to geographic information systems (GIS) software, statisticians and data analysts routinely encounter scientific data sets with geocoded locations. This has generated considerable interest in statistical modeling for location-referenced spatial data. In public health, spatial data routinely arise as aggregates over regions, such as counts or rates over counties, census tracts, or some other administrative delineation. Such data are often referred to as areal data. This review article provides a brief overview of statistical models that account for spatial dependence in areal data. It does so in the context of two applications: disease mapping and spatial survival analysis. Disease maps are used to highlight geographic areas with high and low prevalence, incidence, or mortality rates of a specific disease and the variability of such rates over a spatial domain. They can also be used to detect hot spots or spatial clusters that may arise owing to common environmental, demographic, or cultural effects shared by neighboring regions. Spatial survival analysis refers to the modeling and analysis for geographically referenced time-to-event data, where a subject is followed up to an event (e.g., death or onset of a disease) or is censored, whichever comes first. Spatial survival analysis is used to analyze clustered survival data when the clustering arises from geographical regions or strata. Illustrations are provided in these application domains.

  14. On strategic spatial planning

    Directory of Open Access Journals (Sweden)

    Tošić Branka

    2014-01-01

    Full Text Available The goal of this paper is to explain the origin and development of strategic spatial planning, to show complex features and highlight the differences and/or advantages over traditional, physical spatial planning. Strategic spatial planning is seen as one of approaches in legally defined planning documents, and throughout the display of properties of sectoral national strategies, as well as issues of strategic planning at the local level in Serbia. The strategic approach is clearly recognized at the national and sub-national level of spatial planning in European countries and in our country. It has been confirmed by the goals outlined in documents of the European Union and Serbia that promote the grounds of territorial cohesion and strategic integrated planning, emphasizing cooperation and the principles of sustainable spatial development. [Projekat Ministarstva nauke Republike Srbije, br. 176017

  15. The spatial rotator

    DEFF Research Database (Denmark)

    Rasmusson, Allan; Hahn, Ute; Larsen, Jytte Overgaard

    2013-01-01

    to identify the specific tissue region under study. In order to use the spatial rotator in practice, however, it is necessary to be able to identify intersection points between cell boundaries and test rays in a series of parallel focal planes, also at the peripheral parts of the cell boundaries. In cases......This paper presents a new local volume estimator, the spatial rotator, which is based on measurements on a virtual 3D probe, using computer assisted microscopy. The basic design of the probe builds upon the rotator principle which requires only a few manual intersection markings, thus making...... the spatial rotator fast to use. Since a 3D probe is involved, it is expected that the spatial rotator will be more efficient than the the nucleator and the planar rotator, which are based on measurements in a single plane. An extensive simulation study shows that the spatial rotator may be more efficient...

  16. Spatial interpolation approach based on IDW with anisotropic spatial structures

    Science.gov (United States)

    Li, Jia; Duan, Ping; Sheng, Yehua; Lv, Haiyang

    2015-12-01

    In many interpolation methods, with its simple interpolation principle, Inverse distance weighted (IDW) interpolation is one of the most common interpolation method. There are anisotropic spatial structures with actual geographical spatial phenomenon. When the IDW interpolation is used, anisotropic spatial structures should be considered. Geostatistical theory has a characteristics of exploring anisotropic spatial structures. In this paper, spatial interpolation approach based on IDW with anisotropic spatial structures is proposed. The DEM data is tested in this paper to prove reliability of the IDW interpolation considering anisotropic spatial structures. Experimental results show that IDW interpolation considering anisotropic spatial structures can improve interpolation precision when sampling data has anisotropic spatial structures feature.

  17. Spatial aggregations for spatial based decision making in spatial data warehouses

    Institute of Scientific and Technical Information of China (English)

    ByeongSeob You; DongWook Lee; SangHun Eo; SookKyung Cho; HaeYoung Bae

    2007-01-01

    For spatial based decision making such as choice of best place to construct a new department store, spatial data warehousing system is required more and more previous spatial data warehousing systems; however, provided decision making of non-spatial data on a map and so those cannot support enough spatial based decision making. The spatial aggregations are proposed for spatial based decision making in spatial data warehouses. The meaning of aggregation operators for applying spatial data was modified and new spatial aggregations were defined. These aggregations can support hierarchical concept of spatial measure. Using these aggregations, the spatial analysis classified by non-spatial data is provided. In case study, how to use these aggregations and how to support spatial based decision making are shown.

  18. Collective spatial keyword querying

    DEFF Research Database (Denmark)

    Cao, Xin; Cong, Gao; Jensen, Christian S.;

    2011-01-01

    With the proliferation of geo-positioning and geo-tagging, spatial web objects that possess both a geographical location and a textual description are gaining in prevalence, and spatial keyword queries that exploit both location and textual description are gaining in prominence. However......, the queries studied so far generally focus on finding individual objects that each satisfy a query rather than finding groups of objects where the objects in a group collectively satisfy a query. We define the problem of retrieving a group of spatial web objects such that the group's keywords cover the query...

  19. Non-standard spatial statistics and spatial econometrics

    CERN Document Server

    Griffith, Daniel A

    2011-01-01

    Spatial statistics and spatial econometrics are recent sprouts of the tree "spatial analysis with measurement". Still, several general themes have emerged. Exploring selected fields of possible interest is tantalizing, and this is what the authors aim here.

  20. Geologic spatial analysis

    Energy Technology Data Exchange (ETDEWEB)

    Thiessen, R.L.; Eliason, J.R.

    1989-01-01

    This report describes the development of geologic spatial analysis research which focuses on conducting comprehensive three-dimensional analysis of regions using geologic data sets that can be referenced by latitude, longitude, and elevation/depth. (CBS)

  1. Spatial Data Supply Chains

    Science.gov (United States)

    Varadharajulu, P.; Azeem Saqiq, M.; Yu, F.; McMeekin, D. A.; West, G.; Arnold, L.; Moncrieff, S.

    2015-06-01

    This paper describes current research into the supply of spatial data to the end user in as close to real time as possible via the World Wide Web. The Spatial Data Infrastructure paradigm has been discussed since the early 1990s. The concept has evolved significantly since then but has almost always examined data from the perspective of the supplier. It has been a supplier driven focus rather than a user driven focus. The current research being conducted is making a paradigm shift and looking at the supply of spatial data as a supply chain, similar to a manufacturing supply chain in which users play a significant part. A comprehensive consultation process took place within Australia and New Zealand incorporating a large number of stakeholders. Three research projects that have arisen from this consultation process are examining Spatial Data Supply Chains within Australia and New Zealand and are discussed within this paper.

  2. Spatial cluster modelling

    CERN Document Server

    Lawson, Andrew B

    2002-01-01

    Research has generated a number of advances in methods for spatial cluster modelling in recent years, particularly in the area of Bayesian cluster modelling. Along with these advances has come an explosion of interest in the potential applications of this work, especially in epidemiology and genome research. In one integrated volume, this book reviews the state-of-the-art in spatial clustering and spatial cluster modelling, bringing together research and applications previously scattered throughout the literature. It begins with an overview of the field, then presents a series of chapters that illuminate the nature and purpose of cluster modelling within different application areas, including astrophysics, epidemiology, ecology, and imaging. The focus then shifts to methods, with discussions on point and object process modelling, perfect sampling of cluster processes, partitioning in space and space-time, spatial and spatio-temporal process modelling, nonparametric methods for clustering, and spatio-temporal ...

  3. Spatial recurrence plots.

    Science.gov (United States)

    Vasconcelos, D B; Lopes, S R; Viana, R L; Kurths, J

    2006-05-01

    We propose an extension of the recurrence plot concept to perform quantitative analyzes of roughness and disorder of spatial patterns at a fixed time. We introduce spatial recurrence plots (SRPs) as a graphical representation of the pointwise correlation matrix, in terms of a two-dimensional spatial return plot. This technique is applied to the study of complex patterns generated by coupled map lattices, which are characterized by measures of complexity based on SRPs. We show that the complexity measures we propose for SRPs provide a systematic way of investigating the distribution of spatially coherent structures, such as synchronization domains, in lattice profiles. This approach has potential for many more applications, e.g., in surface roughness analyzes.

  4. spatially identifying vulnerable areas

    African Journals Online (AJOL)

    System (SMDSS) to identify factors that make forest and game reserves vulnerable .... involve the creation of a Digital Elevation Model (DEM), Slope Settlement and ... Feature). Spatial. Analyst Tool. (Slope). Buffer Tool. Buffer Tool. Buffer Tool.

  5. Stability of Spatial Equilibrium

    OpenAIRE

    Tabuchi, Takatoshi; Dao-Zhi, Zeng

    2000-01-01

    This paper focuses on externalities between economic agents. We consider spatial dis- tribution of economic activities in a multiregional dynamical system, where regions may be interpreted as clubs, social subgroups, species, or strategies. Our dynamics includes gravity models and replicator dynamics as special cases. Assuming that other variables, such as prices are solved as a function of the population distribution, we analyze both interior and corner equilibria of spatial distribution in ...

  6. Software for Spatial Statistics

    Directory of Open Access Journals (Sweden)

    Edzer Pebesma

    2015-02-01

    Full Text Available We give an overview of the papers published in this special issue on spatial statistics, of the Journal of Statistical Software. 21 papers address issues covering visualization (micromaps, links to Google Maps or Google Earth, point pattern analysis, geostatistics, analysis of areal aggregated or lattice data, spatio-temporal statistics, Bayesian spatial statistics, and Laplace approximations. We also point to earlier publications in this journal on the same topic.

  7. Software for Spatial Statistics

    OpenAIRE

    Edzer Pebesma; Roger Bivand; Paulo Justiniano Ribeiro

    2015-01-01

    We give an overview of the papers published in this special issue on spatial statistics, of the Journal of Statistical Software. 21 papers address issues covering visualization (micromaps, links to Google Maps or Google Earth), point pattern analysis, geostatistics, analysis of areal aggregated or lattice data, spatio-temporal statistics, Bayesian spatial statistics, and Laplace approximations. We also point to earlier publications in this journal on the same topic.

  8. Spatial Learning in Dragonflies

    OpenAIRE

    Eason, Perri K.; Switzer, Paul V.

    2006-01-01

    Spatial learning is evident in dragonflies on a variety of spatial scales. Mature dragonflies must be able to locate a variety of features in the habitat that are critical to survival and reproduction, including sites for breeding, foraging, roosting, and thermoregulating. In many species, these sites do not coincide in space. Because individuals may repeatedly use particular sites for different activities, they must learn both the locations of these sites and routes among them. Further evide...

  9. Teaching Spatial Awareness to Children

    Science.gov (United States)

    Stevens-Smith, Deborah

    2004-01-01

    An important component in the early stages of skill development is spatial awareness. This article discusses how good spatial awareness in children results from concepts that are reinforced throughout the school's curriculum. Activities for developing spatial awareness are also provided.

  10. Diffusion on spatial network

    Science.gov (United States)

    Hui, Zi; Tang, Xiaoyue; Li, Wei; Greneche, Jean-Marc; Wang, Qiuping A.

    2015-04-01

    In this work, we study the problem of diffusing a product (idea, opinion, disease etc.) among agents on spatial network. The network is constructed by random addition of nodes on the planar. The probability for a previous node to be connected to the new one is inversely proportional to their spatial distance to the power of α. The diffusion rate between two connected nodes is inversely proportional to their spatial distance to the power of β as well. Inspired from the Fick's first law, we introduce the diffusion coefficient to measure the diffusion ability of the spatial network. Using both theoretical analysis and Monte Carlo simulation, we get the fact that the diffusion coefficient always decreases with the increasing of parameter α and β, and the diffusion sub-coefficient follows the power-law of the spatial distance with exponent equals to -α-β+2. Since both short-range diffusion and long-range diffusion exist, we use anomalous diffusion method in diffusion process. We get the fact that the slope index δ in anomalous diffusion is always smaller that 1. The diffusion process in our model is sub-diffusion.

  11. Differentially Private Spatial Decompositions

    CERN Document Server

    Cormode, Graham; Shen, Entong; Srivastava, Divesh; Yu, Ting

    2011-01-01

    Differential privacy has recently emerged as the de facto standard for private data release. This makes it possible to provide strong theoretical guarantees on the privacy and utility of released data. While it is well-known how to release data based on counts and simple functions under this guarantee, it remains to provide general purpose techniques to release different kinds of data. In this paper, we focus on spatial data such as locations and more generally any data that can be indexed by a tree structure. Directly applying existing differential privacy methods to this type of data simply generates noise. Instead, we introduce a new class of "private spatial decompositions": these adapt standard spatial indexing methods such as quadtrees and kd-trees to provide a private description of the data distribution. Equipping such structures with differential privacy requires several steps to ensure that they provide meaningful privacy guarantees. Various primitives, such as choosing splitting points and describi...

  12. Training generalized spatial skills.

    Science.gov (United States)

    Wright, Rebecca; Thompson, William L; Ganis, Giorgio; Newcombe, Nora S; Kosslyn, Stephen M

    2008-08-01

    Spatial transformation skills are an essential aspect of cognitive ability. These skills can be improved by practice, but such improvement has usually been specific to tasks and stimuli. The present study investigated whether intensive long-term practice leads to change that transcends stimulus and task parameters. Thirty-one participants (14 male, 17 female) were tested on three cognitive tasks: a computerized version of the Shepard-Metzler (1971) mental rotation task (MRT), a mental paper-folding task (MPFT), and a verbal analogies task (VAT). Each individual then participated in daily practice sessions with the MRT or the MPFT over 21 days. Postpractice comparisons revealed transfer of practice gains to novel stimuli for the practiced task, as well as transfer to the other, nonpracticed spatial task. Thus, practice effects were process based, not instance based. Improvement in the nonpracticed spatial task was greater than that in the VAT; thus, improvement was not merely due to greater ease with computerized testing.

  13. Spatiality of environmental law

    DEFF Research Database (Denmark)

    Baaner, Lasse; Hvingel, Line

    2015-01-01

    , examines legal regulation as spatial information. It aims to deepen the understanding of spatiality as a core element of environmental law, and to connect it to the basic concept of representation used in giscience. It concludes that the future path for e-Government demands a shift in legal paradigm, from......Digital society challenges the traditional perception of legal sources. The use of maps as a basis for public administration dates far back, but e-Government’s use of digital maps that include legal information creates new legal obstacles. In the coming decades, the inspire directive of 2007...... will determine the interplay between geographic data and technology in the fields of environmental legislation, environmental policy and environmental management. This article examines the legal regulation of spatial information as established by the inspire directive, on one hand, and on the other hand...

  14. A spatial entropy reflecting distribution of spatial objects

    Institute of Scientific and Technical Information of China (English)

    Youn-Kyung Jang; Byeong-Seob You; Ho-Seok Kim; Kyoung-Bae Kim; Hae-Young Bae

    2007-01-01

    Decision trees are mainly used to classify data and predict data classes. A spatial decision tree has been designed using Euclidean distance between objects for reflecting spatial data characteristic. Even though this method explains the distance of objects in spatial dimension, it fails to represent distributions of spatial data and their relationships. But distributions of spatial data and relationships with their neighborhoods are very important in real world. This paper proposes decision tree based on spatial entropy that represents distributions of spatial data with dispersion and dissimilarity. The rate of dispersion by dissimilarity presents how related distribution of spatial data and non-spatial attributes. The experiment evaluates the accuracy and building time of decision tree as compared to previous methods and it shows that the proposed method makes efficient and scalable classification for spatial decision support.

  15. Spatially Embedded Inequality

    DEFF Research Database (Denmark)

    Holck, Lotte

    2016-01-01

    /methodology/approach: – The (re)production of inequality is explored by linking research on organizational space with HRM diversity management. Data from an ethnographic study undertaken in a Danish municipal center illustrates how a substructure of inequality is spatially upheld alongside a formal diversity policy. Archer...... the more subtle, spatially embedded forms of inequality. Originality/value: – Theoretical and empirical connections between research on organizational space and HRM diversity management have thus far not been systematically studied. This combination might advance knowledge on the persistence of micro...

  16. Spatially Resolved Artificial Chemistry

    DEFF Research Database (Denmark)

    Fellermann, Harold

    2009-01-01

    Although spatial structures can play a crucial role in chemical systems and can drastically alter the outcome of reactions, the traditional framework of artificial chemistry is a well-stirred tank reactor with no spatial representation in mind. Advanced method development in physical chemistry has...... made a class of models accessible to the realms of artificial chemistry that represent reacting molecules in a coarse-grained fashion in continuous space. This chapter introduces the mathematical models of Brownian dynamics (BD) and dissipative particle dynamics (DPD) for molecular motion and reaction...

  17. Spatial fluctuation theorem

    Science.gov (United States)

    Pérez-Espigares, Carlos; Redig, Frank; Giardinà, Cristian

    2015-08-01

    For non-equilibrium systems of interacting particles and for interacting diffusions in d-dimensions, a novel fluctuation relation is derived. The theorem establishes a quantitative relation between the probabilities of observing two current values in different spatial directions. The result is a consequence of spatial symmetries of the microscopic dynamics, generalizing in this way the Gallavotti-Cohen fluctuation theorem related to the time-reversal symmetry. This new perspective opens up the possibility of direct experimental measurements of fluctuation relations of vectorial observables.

  18. Historical Evolution of Spatial Abilities

    Directory of Open Access Journals (Sweden)

    A. Ardila

    1993-01-01

    Full Text Available Historical evolution and cross-cultural differences in spatial abilities are analyzed. Spatial abilities have been found to be significantly associated with the complexity of geographical conditions and survival demands. Although impaired spatial cognition is found in cases of, exclusively or predominantly, right hemisphere pathology, it is proposed that this asymmetry may depend on the degree of training in spatial abilities. It is further proposed that spatial cognition might have evolved in a parallel way with cultural evolution and environmental demands. Contemporary city humans might be using spatial abilities in some new, conceptual tasks that did not exist in prehistoric times: mathematics, reading, writing, mechanics, music, etc. Cross-cultural analysis of spatial abilities in different human groups, normalization of neuropsychological testing instruments, and clinical observations of spatial ability disturbances in people with different cultural backgrounds and various spatial requirements, are required to construct a neuropsychological theory of brain organization of spatial cognition.

  19. Handbook of Spatial Cognition

    Science.gov (United States)

    Waller, David, Ed.; Nadel, Lynn, Ed.

    2012-01-01

    Spatial cognition is a branch of cognitive psychology that studies how people acquire and use knowledge about their environment to determine where they are, how to obtain resources, and how to find their way home. Researchers from a wide range of disciplines, including neuroscience, cognition, and sociology, have discovered a great deal about how…

  20. Spatial Keyword Query Processing

    DEFF Research Database (Denmark)

    Chen, Lisi; Jensen, Christian S.; Wu, Dingming

    2013-01-01

    an all-around survey of 12 state- of-the-art geo-textual indices. We propose a benchmark that en- ables the comparison of the spatial keyword query performance. We also report on the findings obtained when applying the bench- mark to the indices, thus uncovering new insights that may guide index...

  1. Describing migration spatial structure

    NARCIS (Netherlands)

    Rogers, A; Willekens, F; Little, J; Raymer, J

    The age structure of a population is a fundamental concept in demography and is generally depicted in the form of an age pyramid. The spatial structure of an interregional system of origin-destination-specific migration streams is, however, a notion lacking a widely accepted definition. We offer a

  2. Spatial Terahertz Modulator

    Science.gov (United States)

    Xie, Zhenwei; Wang, Xinke; Ye, Jiasheng; Feng, Shengfei; Sun, Wenfeng; Akalin, Tahsin; Zhang, Yan

    2013-11-01

    Terahertz (THz) technology is a developing and promising candidate for biological imaging, security inspection and communications, due to the low photon energy, the high transparency and the broad band properties of the THz radiation. However, a major encountered bottleneck is lack of efficient devices to manipulate the THz wave, especially to modulate the THz wave front. A wave front modulator should allow the optical or electrical control of the spatial transmission (or reflection) of an input THz wave and hence the ability to encode the information in a wave front. Here we propose a spatial THz modulator (STM) to dynamically control the THz wave front with photo-generated carriers. A computer generated THz hologram is projected onto a silicon wafer by a conventional spatial light modulator (SLM). The corresponding photo-generated carrier spatial distribution will be induced, which forms an amplitude hologram to modulate the wave front of the input THz beam. Some special intensity patterns and vortex beams are generated by using this method. This all-optical controllable STM is structure free, high resolution and broadband. It is expected to be widely used in future THz imaging and communication systems.

  3. Handbook of Spatial Cognition

    Science.gov (United States)

    Waller, David, Ed.; Nadel, Lynn, Ed.

    2012-01-01

    Spatial cognition is a branch of cognitive psychology that studies how people acquire and use knowledge about their environment to determine where they are, how to obtain resources, and how to find their way home. Researchers from a wide range of disciplines, including neuroscience, cognition, and sociology, have discovered a great deal about how…

  4. Assessing spatial data infrastructures

    NARCIS (Netherlands)

    Grus, L.

    2010-01-01

    Over the last two decades many countries and regions throughout the world have taken steps to establish Spatial Data Infrastructures (SDIs). Developing SDIs requires a considerable amount of time, energy and financial resources. Therefore it is increasingly important to assess SDI outcomes in order

  5. Creating spatial organizations

    NARCIS (Netherlands)

    Lekanne Deprez, F.R.E.; Tissen, R.J.

    2009-01-01

    This paper addresses the spatial design of modern organizations in the context of a fundamental change which is currently taking place in the way companies view their organizations and the inherent performance expectations, requirements and results underlying these. This change involves a managerial

  6. The Spatial Economy

    Science.gov (United States)

    Haggett, Peter

    1978-01-01

    Discusses basic economic factors including resources, labor, and capital and discusses the flows that link them together in a recognizable geographical pattern. Suggests that geographers can contribute to better understanding of the spatial economy by undertaking research with scholars from other disciplines. (Author/DB)

  7. Cartography: LACIE's spatial processor

    Science.gov (United States)

    Rader, M. L.; Vela, R. R. (Principal Investigator)

    1979-01-01

    The spatial processing needs of LACIE include the location of agricultural test sites, and the registration of ground truth to LANDSAT imagery. The technological aspects of LACIE cartographic support, the need for cartography in satellite crop surveys, and proposed improvements which would enhance support of future programs are discussed.

  8. Describing migration spatial structure

    NARCIS (Netherlands)

    Rogers, A; Willekens, F; Little, J; Raymer, J

    2002-01-01

    The age structure of a population is a fundamental concept in demography and is generally depicted in the form of an age pyramid. The spatial structure of an interregional system of origin-destination-specific migration streams is, however, a notion lacking a widely accepted definition. We offer a d

  9. Recurrent Spatial Transformer Networks

    DEFF Research Database (Denmark)

    Sønderby, Søren Kaae; Sønderby, Casper Kaae; Maaløe, Lars;

    2015-01-01

    We integrate the recently proposed spatial transformer network (SPN) [Jaderberg et. al 2015] into a recurrent neural network (RNN) to form an RNN-SPN model. We use the RNN-SPN to classify digits in cluttered MNIST sequences. The proposed model achieves a single digit error of 1.5% compared to 2...

  10. A Spatial Distribution Pattern-driven Spatial Index

    Directory of Open Access Journals (Sweden)

    WU Mingguang

    2015-01-01

    Full Text Available Packing spatial data into blocks and processing of global impact of local operations are two important tasks for spatial index to support bulk operations. In this paper, we present a new spatial index called Pattern-tree for bulk operations with spatial distribution pattern analysis. For packing objects into blocks, a new spatial data partitioning method based on the detection of the spatial distribution pattern was presented. This paper introduces a novel spatial index construction algorithm that combines of top-down and bottom-up methods; For processing of local update operations and its global impact, this paper introduces a new algorithm based on change analysis of the spatial distribution pattern. Empirical results demonstrate that performance improvements are achieved in practice in the case of spatial index construction and windows query compared with STLT, GBI and SCB.

  11. Spatially Dispersed Employee Recovery

    DEFF Research Database (Denmark)

    Hvass, Kristian Anders; Torfadóttir, Embla

    2014-01-01

    Employee recovery addresses either employee well-being or management's practices in aiding employees in recovering themselves following a service failure. This paper surveys the cabin crew at a small, European, low-cost carrier and investigates employees' perceptions of management practices to aid...... personnel achieve service recovery. Employee recovery within service research often focuses on front-line employees that work in a fixed location, however a contribution to the field is made by investigating the recovery of spatially dispersed personnel, such as operational personnel in the transport sector......, who have a work place away from a fixed or central location and have minimal management contact. Results suggest that the support employees receive from management, such as recognition, information sharing, training, and strategic awareness are all important for spatially dispersed front...

  12. Particle detector spatial resolution

    Science.gov (United States)

    Perez-Mendez, V.

    1992-12-15

    Method and apparatus for producing separated columns of scintillation layer material, for use in detection of X-rays and high energy charged particles with improved spatial resolution is disclosed. A pattern of ridges or projections is formed on one surface of a substrate layer or in a thin polyimide layer, and the scintillation layer is grown at controlled temperature and growth rate on the ridge-containing material. The scintillation material preferentially forms cylinders or columns, separated by gaps conforming to the pattern of ridges, and these columns direct most of the light produced in the scintillation layer along individual columns for subsequent detection in a photodiode layer. The gaps may be filled with a light-absorbing material to further enhance the spatial resolution of the particle detector. 12 figs.

  13. Rumlig kultur / Spatial Culture

    DEFF Research Database (Denmark)

    and cultural environments of the modern and contemporary metropolis. The contributions focus on urban and suburban cultures of Copenhagen, New York, Hong Kong, Berlin and anderswo, demonstrating how the precise analysis of cultural and artistic phenomena informs a multilayered understanding......RUMLIG KULTUR / SPATIAL CULTURE præsenterer et humanvidenskabeligt livtag med storbyens erfaringsverden. Emnerne for 21 kapitler spænder fra billedhuggeren Bjørn Nørgaard og boligbyggeriet Bispebjerg Bakke til stedsopfattelsen i moderne guidebøger. Undervjs inddrages bykulturens tænkere såsom Steen...... artikler et forskningsfelt for rumlig kultur, hvori alskens sanse- og refleksionsformer finder sammen. Based in humanistic urban studies as practiced in the Department of Arts and Cultural Studies, University of Copenhagen, SPATIAL CULTURE outlines a novel framework for understanding the social...

  14. SDPG: Spatial Data Processing Grid

    Institute of Scientific and Technical Information of China (English)

    XIAO Nong(肖侬); FUV Wei(付伟)

    2003-01-01

    Spatial applications will gain high complexity as the volume of spatial data increases rapidly. A suitable data processing and computing infrastructure for spatial applications needs to be established. Over the past decade, grid has become a powerful computing environment for data intensive and computing intensive applications. Integrating grid computing with spatial data processing technology, the authors designed a spatial data processing grid (called SDPG) to address the related problems. Requirements of spatial applications are examined and the architecture of SDPG is described in this paper. Key technologies for implementing SDPG are discussed with emphasis.

  15. A Voronoi-based spatial algebra for spatial relations

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Spatial relation between spatial objects is a very important topic for spatial reasoning, query and analysis in geographical information systems (GIS). The most popular models in current use have fundamental deficiencies in theory. In this paper, a generic algebra for spatial relations is presented, in which (i) appropriate operators from set operators (i.e. union, intersection, difference, difference by, symmetric difference, etc.) are utilized to distinguish the spatial relations between neighboring spatial objects; (ii) three types of values are used for the computational results of set operations-content, dimension and number of connected components; and (iii) a spatial object is treated as a whole but the Voronoi region of an object is employed to enhance its interaction with its neighbours. This algebra overcomes the shortcomings of the existing models and it can effectively describe the relations of spatial objects.

  16. GENERATING SOPHISTICATED SPATIAL SURROGATES USING THE MIMS SPATIAL ALLOCATOR

    Science.gov (United States)

    The Multimedia Integrated Modeling System (MIMS) Spatial Allocator is open-source software for generating spatial surrogates for emissions modeling, changing the map projection of Shapefiles, and performing other types of spatial allocation that does not require the use of a comm...

  17. Spatial organization and individual mobility

    Energy Technology Data Exchange (ETDEWEB)

    Maurer, J. [Eidgenoessische Technische Hochschule, Zuerich (Switzerland)

    1996-11-01

    The paper deals with the following topics: the notion of spatial organization or spatial development, present options, considerations concerning the main stream of opinions, and the contribution of science. (author) 13 refs.

  18. Integrated Spatial Filter Array Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To address the NASA Earth Science Division need for spatial filter arrays for amplitude and wavefront control, Luminit proposes to develop a novel Integrated Spatial...

  19. Professional analysis in spatial planning

    Directory of Open Access Journals (Sweden)

    Andrej Černe

    2005-12-01

    Full Text Available Spatial analysis contributes to accomplishment of the three basic aims of spatial planning: it is basic element for setting spatial policies, concepts and strategies, gives basic information to inhabitants, land owners, investors, planners and helps in performing spatial policies, strategies, plans, programmes and projects. Analysis in planning are generally devoted to: understand current circumstances and emerging conditions within planning decisions; determine priorities of open questions and their solutions; formulate general principles for further development.

  20. Spatial Premise Integration in Hindi

    Science.gov (United States)

    Mishra, Ramesh Kumar

    2007-01-01

    Spatial reasoning or locating objects in a spatial space has long been an important area of research in cognitive science because analyzing space categorically and finding objects is a fundamental act of mental perception and cognition. Premise integration in tasks of spatial reasoning has recently received considerable research attention. This is…

  1. Spatial Premise Integration in Hindi

    Science.gov (United States)

    Mishra, Ramesh Kumar

    2007-01-01

    Spatial reasoning or locating objects in a spatial space has long been an important area of research in cognitive science because analyzing space categorically and finding objects is a fundamental act of mental perception and cognition. Premise integration in tasks of spatial reasoning has recently received considerable research attention. This is…

  2. Marine Spatial Data Infrastruktur

    DEFF Research Database (Denmark)

    Stigsen, Tino Kastbjerg; Weber, Michael; Hvingel, Line Træholt

    2011-01-01

    En bæredygtig fremtid har stået højt på den politiske dagsorden siden Brundtlandsrapporten udkom i 1987. Geodata spiller en væsentlig rolle i opfyldelse af dette mål. Med udgangspunkt i geodata kan der skabes en datainfrastruktur, der kan være med til at understøtte den planlægning, administratio...... Enabled Society, såvel som i teorier om digital forvaltning (eGovernment). Alle diskurser anerkender vigtigheden af Spatial Data Infrastructure (SDI), og dermed af geodata, som et redskab og katalysator for processen....

  3. Spatially localized magnetoconvection

    Energy Technology Data Exchange (ETDEWEB)

    Lo Jacono, D; Bergeon, A [Universite de Toulouse (France); INPT, UPS, Institut de Mecanique des Fluides de Toulouse (IMFT), Allee Camille Soula, F-31400 Toulouse (France); Knobloch, E, E-mail: lojacono@imft.fr, E-mail: bergeon@imft.fr, E-mail: knobloch@berkeley.edu [Department of Physics, University of California, Berkeley, CA 94720 (United States)

    2012-06-01

    Numerical continuation is used to compute branches of time-independent, spatially localized convectons in an imposed vertical magnetic field focusing on values of the Chandrasekhar number Q in the range 10 < Q < 10{sup 3}. The calculations reveal that convectons initially grow by nucleating additional cells on either side, but with the build-up of field outside owing to flux expulsion, the convectons are able to transport more heat only by expanding the constituent cells. Thus, at large Q and large Rayleigh numbers, convectons consist of a small number of broad cells. (paper)

  4. Spatial manipulation with microfluidics

    Directory of Open Access Journals (Sweden)

    Benjamin eLin

    2015-04-01

    Full Text Available Biochemical gradients convey information through space, time, and concentration, and are ultimately capable of spatially resolving distinct cellular phenotypes, such as differentiation, proliferation, and migration. How these gradients develop, evolve, and function during development, homeostasis, and various disease states is a subject of intense interest across a variety of disciplines. Microfluidic technologies have become essential tools for investigating gradient sensing in vitro due to their ability to precisely manipulate fluids on demand in well controlled environments at cellular length scales. This minireview will highlight their utility for studying gradient sensing along with relevant applications to biology.

  5. The Spatial Curvature Endgame

    CERN Document Server

    Leonard, C Danielle; Allison, Rupert

    2016-01-01

    Current constraints on spatial curvature show that it is dynamically negligible: $|\\Omega_{\\rm K}| \\lesssim 5 \\times 10^{-3}$ (95% CL). Neglecting it as a cosmological parameter would be premature however, as more stringent constraints on $\\Omega_{\\rm K}$ at around the $10^{-4}$ level would offer valuable tests of eternal inflation models and probe novel large-scale structure phenomena. This precision also represents the "curvature floor", beyond which constraints cannot be meaningfully improved due to the cosmic variance of horizon-scale perturbations. In this paper, we discuss what future experiments will need to do in order to measure spatial curvature to this maximum accuracy. Our conservative forecasts show that the curvature floor is unreachable - by an order of magnitude - even with Stage IV experiments, unless strong assumptions are made about dark energy evolution and the optical depth to the CMB. We also discuss some of the novel problems that arise when attempting to constrain a global cosmological...

  6. Spatial Game Analytics and Visualization

    DEFF Research Database (Denmark)

    Drachen, Anders; Schubert, Matthias

    2013-01-01

    The recently emerged field of game analytics and the development and adaptation of business intelligence techniques to support game design and development has given data-driven techniques a direct role in game development. Given that all digital games contain some sort of spatial operation...... for a continuing development. This paper presents a review of current work on spatial and spatio-temporal game analytics across industry and research, describing and defining the key terminology, outlining current techniques and their application. We summarize the current problems and challenges in the field......, and present four key areas of spatial and spatio-temporal analytics: Spatial Outlier Detection, Spatial Clustering, Spatial Predictive Models, Spatial Pattern and Rule Mining. All key areas are well-established outside the context of games and hold the potential to reshape the research roadmap in game...

  7. The Spatiale Rotator

    DEFF Research Database (Denmark)

    Rasmusson, Allan

    2009-01-01

    is obeyed by randomizing the orientation of the virtual probe itself within the thick section. Overall, the benefit is that positional information is kept for any block and section of the specimen. As the Spatial Rotator is a 3D probe, data must be gathered from sections thicker than 25 micro meters to form......The inherent demand for unbiasedness for some stereological estimators imposes a demand of not only positional uniform randomness but also isotropic randomness, i.e. directional uniform randomness. In order to comply with isotropy, one must perform a random rotation of the object of interest before...... it is embedded and sectioned. This has the unfortunate side effect that all information about positioning within the object is lost for blocks and sections. For complex tissue, like the mammalian brain, this information is of utmost importance to ensure measurements are performed in the correct region...

  8. Spatial Standard Observer

    Science.gov (United States)

    Watson, Andrew B. (Inventor)

    2012-01-01

    The present invention relates to devices and methods for the measurement and/or for the specification of the perceptual intensity of a visual image, or the perceptual distance between a pair of images. Grayscale test and reference images are processed to produce test and reference luminance images. A luminance filter function is convolved with the reference luminance image to produce a local mean luminance reference image. Test and reference contrast images are produced from the local mean luminance reference image and the test and reference luminance images respectively, followed by application of a contrast sensitivity filter. The resulting images are combined according to mathematical prescriptions to produce a Just Noticeable Difference, JND value, indicative of a Spatial Standard Observer, SSO. Some embodiments include masking functions, window functions, special treatment for images lying on or near borders and pre-processing of test images.

  9. Sharp spatially constrained inversion

    DEFF Research Database (Denmark)

    Vignoli, Giulio G.; Fiandaca, Gianluca G.; Christiansen, Anders Vest C A.V.C.;

    2013-01-01

    We present sharp reconstruction of multi-layer models using a spatially constrained inversion with minimum gradient support regularization. In particular, its application to airborne electromagnetic data is discussed. Airborne surveys produce extremely large datasets, traditionally inverted...... by using smoothly varying 1D models. Smoothness is a result of the regularization constraints applied to address the inversion ill-posedness. The standard Occam-type regularized multi-layer inversion produces results where boundaries between layers are smeared. The sharp regularization overcomes......, the results are compatible with the data and, at the same time, favor sharp transitions. The focusing strategy can also be used to constrain the 1D solutions laterally, guaranteeing that lateral sharp transitions are retrieved without losing resolution. By means of real and synthetic datasets, sharp...

  10. Spatially enabled land administration

    DEFF Research Database (Denmark)

    Enemark, Stig

    2006-01-01

    . In other words: Good governance and sustainable development is not attainable without sound land administration or - more broadly – sound land management. The paper presents a land management vision that incorporates the benefits of ICT enabled land administration functions. The idea is that spatial...... enabling of land administration systems managing tenure, valuation, planning, and development will allow the information generated by these activities to be much more useful. Also, the services available to private and public sectors and to community organisations should commensurably improve. Knowledge...... the communication between administrative systems and also establish more reliable data due to the use the original data instead of copies. In Denmark, such governmental guidelines for a service-oriented ITarchitecture in support of e-government are recently adopted. Finally, the paper presents the role of FIG...

  11. Spatially enabling the health sector

    Directory of Open Access Journals (Sweden)

    Tarun Stephen Weeramanthri

    2016-11-01

    Full Text Available Spatial information describes the physical location of either people or objects, and the measured relationships between them. In this article we offer the view that greater utilisation of spatial information and its related technology, as part of a broader redesign of the architecture of health information at local and national levels, could assist and speed up the process of health reform, which is taking place across the globe in richer and poorer countries alike.In making this point, we describe the impetus for health sector reform, recent developments in spatial information and analytics, and current Australasian spatial health research. We highlight examples of uptake of spatial information by the health sector, as well as missed opportunities. Our recommendations to spatially enable the health sector are applicable to high and low-resource settings.

  12. Deriving Extensional Spatial Composition Tables

    Science.gov (United States)

    El-Geresy, Baher; Abdelmoty, Alia I.; Ware, Andrew J.

    Spatial composition tables are fundamental tools for the realisation of qualitative spatial reasoning techniques. Studying the properties of these tables in relation to the spatial calculi they are based on is essential for understanding the applicability of these calculi and how they can be extended and generalised. An extensional interpretation of a spatial composition table is an important property that has been studied in the literature and is used to determine the validity of the table for the models it is proposed for. It provides means for consistency checking of ground sets of relations and for addressing spatial constraint satisfaction problems. Furthermore, two general conditions that can be used to test for extensionality of spatial composition tables are proposed and applied to the RCC8 composition table to verify the allowable models in this calculus.

  13. Federated Spatial Databases and Interoperability

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    It is a period of information explosion. Especially for spatialinfo rmation science, information can be acquired through many ways, such as man-mad e planet, aeroplane, laser, digital photogrammetry and so on. Spatial data source s are usually distributed and heterogeneous. Federated database is the best reso lution for the share and interoperation of spatial database. In this paper, the concepts of federated database and interoperability are introduced. Three hetero geneous kinds of spatial data, vector, image and DEM are used to create integrat ed database. A data model of federated spatial databases is given

  14. Tomography of Spatial Mode Detectors

    CERN Document Server

    Bobrov, Ivan; Markov, Anton; Straupe, Stanislav; Kulik, Sergey

    2014-01-01

    Transformation and detection of photons in higher-order spatial modes usually requires complicated holographic techniques. Detectors based on spatial holograms suffer from non-idealities and should be carefully calibrated. We report a novel method for analyzing the quality of projective measurements in spatial mode basis inspired by quantum detector tomography. It allows us to calibrate the detector response using only gaussian beams. We experimentally investigate the inherent inaccuracy of the existing methods of mode transformation and provide a full statistical reconstruction of the POVM (positive operator valued measure) elements for holographic spatial mode detectors.

  15. On the Spatial Ambiguity Function

    CERN Document Server

    Yuryev, Arthur N

    2014-01-01

    The ambiguity function of a spatial signal in the "signal spatial frequency displacement vs antenna linear displacement" coordinates is considered in this paper; in case of a monochromatic signal with known carrier frequency, spatial signal vector angular displacement is considered as the second coordinate. The analysis is made taking into account an external (reradiated or thermal) background which contributes considerable peculiarities in the properties of the spatial ambiguity function. Accuracy of measuring the signal linear or angular displacement and resolution are determined. Examples for the Fresnel and Fraunhofer zones are given.

  16. [Spatial orientation under microgravity].

    Science.gov (United States)

    Koizuka, Izumi

    2012-01-01

    On Earth, humans are constantly exposed to the gravity. During head and body tilts, the otolith organs sense changes in head orientation with respect to the gravitational vertical. These graviceptors also transduce transient linear acceleration generated by translational head motion and centripetal acceleration during rotation about a distant axis. When individuals are rotated at a constant velocity in a centrifuge, they sense the direction of the summed gravitational and centripetal acceleration as the vertical in the steady state. Consequently they experience a roll-tilt of the body when upright and oriented either left-ear-out or right-ear-out. This perception of tilt has been called the somatogravic illusion. Under the microgravity, the graviceptors no longer respond during static tilt of the head or head and body, but they are still activated by linear acceleration. Adaptation to weightlessness early in space flight has been proposed to entail a reinterpretation of the signals from the graviceptors (primarily the otolith organs), so that on return to Earth pitch or roll of the head with respect to the vertical is sensed as fore-aft or left-right translation. In this article, formulation of the spatial orientation on the earth and under microgravity was described.

  17. Spatial Language and Children’s Spatial Landmark Use

    Directory of Open Access Journals (Sweden)

    Amber A. Ankowski

    2012-01-01

    Full Text Available We examined how spatial language affected search behavior in a landmark spatial search task. In Experiment 1, two- to six-year-old children were trained to find a toy in the center of a square array of four identical landmarks. Children heard one of three spatial language cues once during the initial training trial (“here,” “in the middle,” “next to this one”. After search performance reached criterion, children received a probe test trial in which the landmark array was expanded. In Experiment 2, two- to four-year-old children participated in the search task and also completed a language comprehension task. Results revealed that children’s spatial language comprehension scores and spatial language cues heard during training trials were related to children’s performance in the search task.

  18. Axially Symmetric, Spatially Homothetic Spacetimes

    CERN Document Server

    Wagh, S M; Wagh, Sanjay M.; Govinder, Keshlan S.

    2002-01-01

    We show that the existence of appropriate spatial homothetic Killing vectors is directly related to the separability of the metric functions for axially symmetric spacetimes. The density profile for such spacetimes is (spatially) arbitrary and admits any equation of state for the matter in the spacetime. When used for studying axisymmetric gravitational collapse, such solutions do not result in a locally naked singularity.

  19. Applying and extending Oracle Spatial

    CERN Document Server

    Simon Gerard Greener, Siva Ravada

    2013-01-01

    This book is an advanced practical guide to applying and extending Oracle Spatial.This book is for existing users of Oracle and Oracle Spatial who have, at a minimum, basic operational experience of using Oracle or an equivalent database. Advanced skills are not required.

  20. Urban Screen and Spatial Dimension

    Directory of Open Access Journals (Sweden)

    Litta Primasari

    2013-11-01

    Full Text Available This paper is discussing about the urban screen phenomena and its influence to spatial dimension in urban space. The visual characteristics which are forming a spatial dimension will be an emphasis to be presented. Urban screen as a visual intervention has an impact to spatial configuration in urban space. The space dimension was not dominated with materiality limitation, but also images. We have to consider that people senses can measure a spatial dimension, knowing as a perception. That is a human visual and mind relation. The spatial dimension has no longer tangible boundary, but also has intangible ones. Spatial dimension in urban screens phenomena is not merely mathematics, nor spatial dimension in physics which are based on a three-dimensional Cartesian coordinate system. Movement can be expressed in other terms, by how far we can move depends on our eyes to catch that space limitation, and how fast we can move is depends on our mind to perceive some visual phenomenon, that is a spatial dimension. So, the dimension will depend on a visual quality that we perceived. The movement of the body and people’s thought will be an important term to generate the space dimension in urban screen phenomenon. The activity of body’s movement and thought will influence the depth of space dimension.

  1. GIS-facilitated spatial narratives

    DEFF Research Database (Denmark)

    Møller-Jensen, Lasse; Jeppesen, Henrik; Kofie, Richard Y.

    2008-01-01

    -based' exploration of sites related to the narrative and as a tool that facilitates the design of spatial narratives before implementation within portable GIS devices. The Google Earth-based visualization of the spatial narrative is created by a Python script that outputs a web-accessible KML format file. The KML...

  2. Building dynamic spatial environmental models

    NARCIS (Netherlands)

    Karssenberg, D.J.

    2003-01-01

    An environmental model is a representation or imitation of complex natural phenomena that can be discerned by human cognitive processes. This thesis deals with the type of environmental models referred to as dynamic spatial environmental models. The word ‘spatial’ refers to the geographic domain whi

  3. Spatial planning of wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-01-01

    This paper proposes guidelines for spatial planning for wind power, based on experience with spatial planning in Belgium, Denmark, France and the Netherlands. In addition experiences from Germany and Ireland have been used. This guidelines quotes all decisive criteria for successful implementation of wind energy: landscape integration, stakeholders involvement, noise and distance from buildings. (author)

  4. Elements of a Spatial Web

    DEFF Research Database (Denmark)

    Jensen, Christian S.

    2010-01-01

    and are relevant to a text argument. An important element in enabling such queries is to be able to rank spatial web objects. Another is to be able to determine the relevance of an object to a query. Yet another is to enable the efficient processing of such queries. The talk covers recent results on spatial web...

  5. Auditory Spatial Perception without Vision

    Science.gov (United States)

    Voss, Patrice

    2016-01-01

    Valuable insights into the role played by visual experience in shaping spatial representations can be gained by studying the effects of visual deprivation on the remaining sensory modalities. For instance, it has long been debated how spatial hearing evolves in the absence of visual input. While several anecdotal accounts tend to associate complete blindness with exceptional hearing abilities, experimental evidence supporting such claims is, however, matched by nearly equal amounts of evidence documenting spatial hearing deficits. The purpose of this review is to summarize the key findings which support either enhancements or deficits in spatial hearing observed following visual loss and to provide a conceptual framework that isolates the specific conditions under which they occur. Available evidence will be examined in terms of spatial dimensions (horizontal, vertical, and depth perception) and in terms of frames of reference (egocentric and allocentric). Evidence suggests that while early blind individuals show superior spatial hearing in the horizontal plane, they also show significant deficits in the vertical plane. Potential explanations underlying these contrasting findings will be discussed. Early blind individuals also show spatial hearing impairments when performing tasks that require the use of an allocentric frame of reference. Results obtained with late-onset blind individuals suggest that early visual experience plays a key role in the development of both spatial hearing enhancements and deficits. PMID:28066286

  6. Modeling for spatial multilevel structural data

    Science.gov (United States)

    Min, Suqin; He, Xiaoqun

    2013-03-01

    The traditional multilevel model assumed independence between groups. However, the datasets grouped by geographical units often has spatial dependence. The individual is influenced not only by its region but also by the adjacent regions, and level-2 residual distribution assumption of traditional multilevel model is violated. In order to deal with such spatial multilevel data, we introduce spatial statistics and spatial econometric models into multilevel model, and apply spatial parameters and adjacency matrix in traditional level-2 model to reflect the spatial autocorrelation. Spatial lag model express spatial effects. We build spatial multilevel model which consider both multilevel thinking and spatial correlation.

  7. Spatial experiences and interaction design

    DEFF Research Database (Denmark)

    Dalsgård, Peter

    2006-01-01

    IT is rapidly spreading to non-desktop environments, and is increasingly being used for post-functional purposes. Recent contributions within the field of interaction design have indicated a tight coupling between physico-spatial and experiential issues, both on a technological and on a theoretical...... level. However, interaction design and HCI yet has little to offer designers working with physico-spatial and experiential issues in practical design cases. In this paper, I argue that experiments that explore spatial and experiential aspects are crucial in developing the practice of interaction design....... These  aspects may be brought to the forefront by engaging in, reflecting upon, and reporting from physico-spatial design experiments, and by making spatial and experience-oriented design representations part of the design process. These experiments may be supported by design representations inspired...

  8. Perspectives on spatial data analysis

    CERN Document Server

    Rey, Sergio

    2010-01-01

    This book takes both a retrospective and prospective view of the field of spatial analysis by combining selected reprints of classic articles by Arthur Getis with current observations by leading experts in the field. Four main aspects are highlighted, dealing with spatial analysis, pattern analysis, local statistics as well as illustrative empirical applications. Researchers and students will gain an appreciation of Getis' methodological contributions to spatial analysis and the broad impact of the methods he has helped pioneer on an impressively broad array of disciplines including spatial epidemiology, demography, economics, and ecology. The volume is a compilation of high impact original contributions, as evidenced by citations, and the latest thinking on the field by leading scholars. This makes the book ideal for advanced seminars and courses in spatial analysis as well as a key resource for researchers seeking a comprehensive overview of recent advances and future directions in the field.

  9. Spatial-temporal data mining

    Science.gov (United States)

    Pokrajac, Dragoljub Milos

    Spatial-temporal data mining techniques have become increasingly important in emerging fields such as remote sensing, precision agriculture, geoscience and brain imaging. In this Thesis, novel spatial-temporal data mining methods and algorithms are presented. After the introductory remarks, modeling spatial-temporal attributes with short observation history using spatial-temporal autoregressive models on uniform grid is explored. Model specifications (including covariance structure and stationarity) are discussed as well as issues in model identification, estimation and forecasting on three different sampling schedules. The proposed technique is experimentally evaluated on simulated spatial-temporal processes that confirm to model assumptions as well as on real-life agricultural data. Subsequently, we proceed with spatial-temporal prediction of a response variable with a partial observability of influential attributes. After mathematical definition of the proposed model, evaluation of the estimation technique on synthetic data that conform to the modeling assumptions is performed and a model is assessed on simulated realistic spatial-temporal data, obtained using the proposed data generator. The following part of the Thesis is dedicated to spatial-temporal profit optimization using neural network modeling. Profit optimization is proposed using a two-phase process that consists of estimation of response/attribute dependence and profit optimization for a particular tuple of attribute values. The proposed method is evaluated on simulated precision agriculture data. Next, we introduce a spatial-temporal data simulator, which is an important tool for evaluation of knowledge discovery methods for spatial-temporal domains. Various aspects of the proposed data generator are discussed, including generation of features and simulation of response variable as well as a practical implementation of the proposed method and its application on experiments with simulated data. The

  10. Six Myths About Spatial Thinking

    Science.gov (United States)

    Newcombe, Nora S.; Stieff, Mike

    2012-04-01

    Visualizations are an increasingly important part of scientific education and discovery. However, users often do not gain knowledge from them in a complete or efficient way. This article aims to direct research on visualizations in science education in productive directions by reviewing the evidence for widespread assumptions that learning styles, sex differences, developmental stages, and spatial language determine the impact of visualizations on science learning. First, we examine the assumption that people differ in their verbal versus visual learning style. Due to the lack of rigorous evaluation, there is no current support for this distinction. Future research should distinguish between two different kinds of visual learning style. Second, we consider the belief that there are large and intractable sex differences in spatial ability resultant from immutable biological reasons. Although there are some spatial sex differences (in some types of spatial tests although not all), there is actually only very mixed support for biological causation. Most important, there is conclusive evidence that spatial skills can be improved through training and education. Third, we explore educators' use of Piaget's ideas about spatial development to draw conclusions about 'developmental appropriateness'. However, recent research on spatial development has focused on identifying sequences that begin with early starting points of skill, and spatial education is possible in some form at all ages. Fourth, although spatial language does not determine spatial thought, it does frame attention in a way that can have impact on learning and understanding. We examine the empirical support for each assumption and its relevance to future research on visualizations in science education.

  11. Emergence of Strange Spatial Pattern in a Spatial Epidemic Model

    Institute of Scientific and Technical Information of China (English)

    SUN Gui-Quan; JIN Zhen; LIU Quan-Xing; LI Li

    2008-01-01

    Pattern formation of a spatial epidemic model with nonlinear incidence rate kI2 S/ (1 + αI2) is investigated. Our results show that strange spatial dynamics, i.e., filament-like pattern, can be obtained by both mathematical analysis and numerical simulation, which are different from the previous results in the spatial epidemic model such as stripe-like or spotted or coexistence of both pattern and so on. The obtained results well extend the finding of pattern formation in the epidemic model and may well explain the distribution of the infected of some epidemic.

  12. Spatial memory in foraging games.

    Science.gov (United States)

    Kerster, Bryan E; Rhodes, Theo; Kello, Christopher T

    2016-03-01

    Foraging and foraging-like processes are found in spatial navigation, memory, visual search, and many other search functions in human cognition and behavior. Foraging is commonly theorized using either random or correlated movements based on Lévy walks, or a series of decisions to remain or leave proximal areas known as "patches". Neither class of model makes use of spatial memory, but search performance may be enhanced when information about searched and unsearched locations is encoded. A video game was developed to test the role of human spatial memory in a canonical foraging task. Analyses of search trajectories from over 2000 human players yielded evidence that foraging movements were inherently clustered, and that clustering was facilitated by spatial memory cues and influenced by memory for spatial locations of targets found. A simple foraging model is presented in which spatial memory is used to integrate aspects of Lévy-based and patch-based foraging theories to perform a kind of area-restricted search, and thereby enhance performance as search unfolds. Using only two free parameters, the model accounts for a variety of findings that individually support competing theories, but together they argue for the integration of spatial memory into theories of foraging.

  13. Mathematical Modeling of spatial disease variables by Spatial Fuzzy Logic for Spatial Decision Support Systems

    Science.gov (United States)

    Platz, M.; Rapp, J.; Groessler, M.; Niehaus, E.; Babu, A.; Soman, B.

    2014-11-01

    A Spatial Decision Support System (SDSS) provides support for decision makers and should not be viewed as replacing human intelligence with machines. Therefore it is reasonable that decision makers are able to use a feature to analyze the provided spatial decision support in detail to crosscheck the digital support of the SDSS with their own expertise. Spatial decision support is based on risk and resource maps in a Geographic Information System (GIS) with relevant layers e.g. environmental, health and socio-economic data. Spatial fuzzy logic allows the representation of spatial properties with a value of truth in the range between 0 and 1. Decision makers can refer to the visualization of the spatial truth of single risk variables of a disease. Spatial fuzzy logic rules that support the allocation of limited resources according to risk can be evaluated with measure theory on topological spaces, which allows to visualize the applicability of this rules as well in a map. Our paper is based on the concept of a spatial fuzzy logic on topological spaces that contributes to the development of an adaptive Early Warning And Response System (EWARS) providing decision support for the current or future spatial distribution of a disease. It supports the decision maker in testing interventions based on available resources and apply risk mitigation strategies and provide guidance tailored to the geo-location of the user via mobile devices. The software component of the system would be based on open source software and the software developed during this project will also be in the open source domain, so that an open community can build on the results and tailor further work to regional or international requirements and constraints. A freely available EWARS Spatial Fuzzy Logic Demo was developed wich enables a user to visualize risk and resource maps based on individual data in several data formats.

  14. Routing Algorithm Exploits Spatial Relations

    Science.gov (United States)

    Okino, Clayton; Jennings, Esther

    2004-01-01

    A recently developed routing algorithm for broadcasting in an ad hoc wireless communication network takes account of, and exploits, the spatial relationships among the locations of nodes, in addition to transmission power levels and distances between the nodes. In contrast, most prior algorithms for discovering routes through ad hoc networks rely heavily on transmission power levels and utilize limited graph-topology techniques that do not involve consideration of the aforesaid spatial relationships. The present algorithm extracts the relevant spatial-relationship information by use of a construct denoted the relative-neighborhood graph (RNG).

  15. Adjacency-preserving spatial treemaps

    Directory of Open Access Journals (Sweden)

    Kevin Buchin

    2016-03-01

    Full Text Available Rectangular layouts, subdivisions of an outer rectangle into smaller rectangles, have many applications in visualizing spatial information, for instance in rectangular cartograms in which the rectangles represent geographic or political regions. A spatial treemap is a rectangular layout with a hierarchical structure: the outer rectangle is subdivided into rectangles that are in turn subdivided into smaller rectangles. We describe algorithms for transforming a rectangular layout that does not have this hierarchical structure, together with a clustering of the rectangles of the layout, into a spatial treemap that respects the clustering and also respects to the extent possible the adjacencies of the input layout.

  16. Local models for spatial analysis

    CERN Document Server

    Lloyd, Christopher D

    2010-01-01

    Focusing on solutions, this second edition provides guidance to a wide variety of real-world problems. The text presents a complete introduction to key concepts and a clear mapping of the methods discussed. It also explores connections between methods. New chapters address spatial patterning in single variables and spatial relations. In addition, every chapter now includes links to key related studies. The author clearly distinguishes between local and global methods and provides more detailed coverage of geographical weighting, image texture measures, local spatial autocorrelation, and multic

  17. GIS-facilitated spatial narratives

    DEFF Research Database (Denmark)

    Møller-Jensen, Lasse; Jeppesen, Henrik; Kofie, Richard Y.

    2008-01-01

    -based' exploration of sites related to the narrative and as a tool that facilitates the design of spatial narratives before implementation within portable GIS devices. The Google Earth-based visualization of the spatial narrative is created by a Python script that outputs a web-accessible KML format file. The KML...... on the thematically and narrative linking of a set of locations within an area. A spatial narrative that describes the - largely unsuccessful - history of Danish plantations on the Gold Coast (1788-1850) is implemented through the Google Earth client. This client is seen both as a type of media in itself for ‘home...

  18. Statistical methods in spatial genetics

    DEFF Research Database (Denmark)

    Guillot, Gilles; Leblois, Raphael; Coulon, Aurelie

    2009-01-01

    The joint analysis of spatial and genetic data is rapidly becoming the norm in population genetics. More and more studies explicitly describe and quantify the spatial organization of genetic variation and try to relate it to underlying ecological processes. As it has become increasingly difficult...... to keep abreast with the latest methodological developments, we review the statistical toolbox available to analyse population genetic data in a spatially explicit framework. We mostly focus on statistical concepts but also discuss practical aspects of the analytical methods, highlighting not only...

  19. Elements of spatial data quality

    CERN Document Server

    Guptill, SC

    1995-01-01

    Elements of Spatial Data Quality outlines the need and suggests potential categories for the content of a comprehensive statement of data quality that must be imbedded in the metadata that accompanies the transfer of a digital spatial data file or is available in a separate metadata catalog. Members of the International Cartographic Association's Commission on Spatial Data Quality have identified seven elements of data quality: positional accuracy, attribute accuracy, completeness, logical consistency, lineage, semantic accuracy and temporal information. In the book the authors describe: compo

  20. Perceptual spatial differentiation of Ljubljana

    Directory of Open Access Journals (Sweden)

    Marko Krevs

    2004-12-01

    Full Text Available Geographical studies of human perception of places at local scale are usually aimed at bet-ter understanding of human spatial perception and knowledge about the places, and of using this knowledge in spatial decision-making or spatial behaviour. Our focus on the first part of these general research aims is presented based on a case study, revealing how residents of the Municipality of Ljubljana perceive and value neighbourhoods of “their” municipality at the beginning of the century1.

  1. Thermodynamic Model of Spatial Memory

    Science.gov (United States)

    Kaufman, Miron; Allen, P.

    1998-03-01

    We develop and test a thermodynamic model of spatial memory. Our model is an application of statistical thermodynamics to cognitive science. It is related to applications of the statistical mechanics framework in parallel distributed processes research. Our macroscopic model allows us to evaluate an entropy associated with spatial memory tasks. We find that older adults exhibit higher levels of entropy than younger adults. Thurstone's Law of Categorical Judgment, according to which the discriminal processes along the psychological continuum produced by presentations of a single stimulus are normally distributed, is explained by using a Hooke spring model of spatial memory. We have also analyzed a nonlinear modification of the ideal spring model of spatial memory. This work is supported by NIH/NIA grant AG09282-06.

  2. Power Consumption in Spatial Cognition

    CERN Document Server

    Odeh, Maha; Verikoukis, Christos

    2012-01-01

    Multiple Input Multiple Output (MIMO) adds a new dimension to be exploited in Cognitive Radio (CR) by simultaneously serving several users. The spatial domain that is added through MIMO is another system resource that has to be optimized, and shared when possible. In this paper, we present a spatial sharing that is carried out through Zero Forcing beamforming (ZFB). Power consumption in such a scenario is discussed and compared to single user case, to evaluate the feasibility of employing spatial cognition from the power perspective. Closed form expressions are derived for the consumed power and data rate at different transmission schemes. Finally, a joint power rate metric is deduced to provide a comprehensive measure of the expediency of spatial cognitive scenario.

  3. Spatial Game Analytics and Visualization

    DEFF Research Database (Denmark)

    Drachen, Anders; Schubert, Matthias

    2013-01-01

    The recently emerged field of game analytics and the development and adaptation of business intelligence techniques to support game design and development has given data-driven techniques a direct role in game development. Given that all digital games contain some sort of spatial operation......, techniques for spatial analysis had their share in these developments. However, the methods for analyzing and visualizing spatial and spatio-temporal patterns in player behavior being used by the game industry are not as diverse as the range of techniques utilized in game research, leaving room...... for a continuing development. This paper presents a review of current work on spatial and spatio-temporal game analytics across industry and research, describing and defining the key terminology, outlining current techniques and their application. We summarize the current problems and challenges in the field...

  4. articles: Describing migration spatial structure

    OpenAIRE

    Andrei Rogers; Frans Willekens; James Raymer; Jani Little

    2002-01-01

    The age structure of a population is a fundamental concept in demography and is generally depicted in the form of an age pyramid. The spatial structure of an interregional system of origin-destination-specific migration streams is, however, a notion lacking a widely accepted definition. We offer a definition in this article, one that draws on the log-linear specification of the geographer's spatial interaction model. We illustrate our definition with observed migration data, we discuss extens...

  5. Basin Assessment Spatial Planning Platform

    Energy Technology Data Exchange (ETDEWEB)

    2017-07-26

    The tool is intended to facilitate hydropower development and water resource planning by improving synthesis and interpretation of disparate spatial datasets that are considered in development actions (e.g., hydrological characteristics, environmentally and culturally sensitive areas, existing or proposed water power resources, climate-informed forecasts). The tool enables this capability by providing a unique framework for assimilating, relating, summarizing, and visualizing disparate spatial data through the use of spatial aggregation techniques, relational geodatabase platforms, and an interactive web-based Geographic Information Systems (GIS). Data are aggregated and related based on shared intersections with a common spatial unit; in this case, industry-standard hydrologic drainage areas for the U.S. (National Hydrography Dataset) are used as the spatial unit to associate planning data. This process is performed using all available scalar delineations of drainage areas (i.e., region, sub-region, basin, sub-basin, watershed, sub-watershed, catchment) to create spatially hierarchical relationships among planning data and drainages. These entity-relationships are stored in a relational geodatabase that provides back-end structure to the web GIS and its widgets. The full technology stack was built using all open-source software in modern programming languages. Interactive widgets that function within the viewport are also compatible with all modern browsers.

  6. Dealing with spatial heterogeneity

    Science.gov (United States)

    Marsily, Gh.; Delay, F.; Gonçalvès, J.; Renard, Ph.; Teles, V.; Violette, S.

    2005-03-01

    Heterogeneity can be dealt with by defining homogeneous equivalent properties, known as averaging, or by trying to describe the spatial variability of the rock properties from geologic observations and local measurements. The techniques available for these descriptions are mostly continuous Geostatistical models, or discontinuous facies models such as the Boolean, Indicator or Gaussian-Threshold models and the Markov chain model. These facies models are better suited to treating issues of rock strata connectivity, e.g. buried high permeability channels or low permeability barriers, which greatly affect flow and, above all, transport in aquifers. Genetic models provide new ways to incorporate more geology into the facies description, an approach that has been well developed in the oil industry, but not enough in hydrogeology. The conclusion is that future work should be focused on improving the facies models, comparing them, and designing new in situ testing procedures (including geophysics) that would help identify the facies geometry and properties. A world-wide catalog of aquifer facies geometry and properties, which could combine site genesis and description with methods used to assess the system, would be of great value for practical applications. On peut aborder le problème de l'hétérogénéité en s'efforçant de définir une perméabilité équivalente homogène, par prise de moyenne, ou au contraire en décrivant la variation dans l'espace des propriétés des roches à partir des observations géologiques et des mesures locales. Les techniques disponibles pour une telle description sont soit continues, comme l'approche Géostatistique, soit discontinues, comme les modèles de faciès, Booléens, ou bien par Indicatrices ou Gaussiennes Seuillées, ou enfin Markoviens. Ces modèles de faciès sont mieux capables de prendre en compte la connectivité des strates géologiques, telles que les chenaux enfouis à forte perméabilité, ou au contraire les faci

  7. Progress in spatial analysis methods and applications

    CERN Document Server

    Páez, Antonio; Buliung, Ron N; Dall'erba, Sandy

    2010-01-01

    This book brings together developments in spatial analysis techniques, including spatial statistics, econometrics, and spatial visualization, and applications to fields such as regional studies, transportation and land use, population and health.

  8. Hamiltonian Dynamics at Spatial Infinity.

    Science.gov (United States)

    Alexander, Matthew

    We employ a projective construction of spatial infinity in four-dimensional spacetimes which are asymptotically flat. In this construction, points of the spatial boundary of the spacetime manifold are identified with congruences of asymptotically parallel spacelike curves that are asymptotically geodesic. It is shown that for this type of construction spatial infinity is represented by a three-dimensional timelike hyperboloid, and that this follows as a consequence of the vacuum Einstein equations. We then construct tensor fields which are defined at spatial infinity, and which embody the information carried by the gravitational field regarding the total mass, linear, and angular momentum of the spacetime. It is shown that these tensor fields must satisfy a set of second order partial differential field equations at spatial infinity. The asymptotic symmetry group implied by the projective construction is examined, and is identified with the Spi group. The field equations satisfied by the tensor fields at spatial infinity can be derived from an action principle, however this action does not appear to be related in any obvious way to the Hilbert-Einstein action of general relativity. Under mappings generated by the Spi group our Lagrangian is left form -invariant, and the corresponding Noether-conserved quantities are examined. It is found that for spacetimes which are stationary or axisymmetric, these conserved quantities are not the limits of the conserved quantities associated with the infinitesimal four-dimensional coordinate transformations. It is shown that using the tensor fields at spatial infinity one can define a set of canonical variables. Further, we show that the "time" derivatives of the configuration variables can be expressed in terms of some of the momentum densities; the remaining momentum densities are constrained. Finally, we construct the Hamiltonian, and examine the transformations generated by it.

  9. Detecting spatial regimes in ecosystems

    Science.gov (United States)

    Sundstrom, Shana M.; Eason, Tarsha; Nelson, R. John; Angeler, David G.; Barichievy, Chris; Garmestani, Ahjond S.; Graham, Nicholas A.J.; Granholm, Dean; Gunderson, Lance; Knutson, Melinda; Nash, Kirsty L.; Spanbauer, Trisha; Stow, Craig A.; Allen, Craig R.

    2017-01-01

    Research on early warning indicators has generally focused on assessing temporal transitions with limited application of these methods to detecting spatial regimes. Traditional spatial boundary detection procedures that result in ecoregion maps are typically based on ecological potential (i.e. potential vegetation), and often fail to account for ongoing changes due to stressors such as land use change and climate change and their effects on plant and animal communities. We use Fisher information, an information theory-based method, on both terrestrial and aquatic animal data (U.S. Breeding Bird Survey and marine zooplankton) to identify ecological boundaries, and compare our results to traditional early warning indicators, conventional ecoregion maps and multivariate analyses such as nMDS and cluster analysis. We successfully detected spatial regimes and transitions in both terrestrial and aquatic systems using Fisher information. Furthermore, Fisher information provided explicit spatial information about community change that is absent from other multivariate approaches. Our results suggest that defining spatial regimes based on animal communities may better reflect ecological reality than do traditional ecoregion maps, especially in our current era of rapid and unpredictable ecological change.

  10. Spatial dependence of extreme rainfall

    Science.gov (United States)

    Radi, Noor Fadhilah Ahmad; Zakaria, Roslinazairimah; Satari, Siti Zanariah; Azman, Muhammad Az-zuhri

    2017-05-01

    This study aims to model the spatial extreme daily rainfall process using the max-stable model. The max-stable model is used to capture the dependence structure of spatial properties of extreme rainfall. Three models from max-stable are considered namely Smith, Schlather and Brown-Resnick models. The methods are applied on 12 selected rainfall stations in Kelantan, Malaysia. Most of the extreme rainfall data occur during wet season from October to December of 1971 to 2012. This period is chosen to assure the available data is enough to satisfy the assumption of stationarity. The dependence parameters including the range and smoothness, are estimated using composite likelihood approach. Then, the bootstrap approach is applied to generate synthetic extreme rainfall data for all models using the estimated dependence parameters. The goodness of fit between the observed extreme rainfall and the synthetic data is assessed using the composite likelihood information criterion (CLIC). Results show that Schlather model is the best followed by Brown-Resnick and Smith models based on the smallest CLIC's value. Thus, the max-stable model is suitable to be used to model extreme rainfall in Kelantan. The study on spatial dependence in extreme rainfall modelling is important to reduce the uncertainties of the point estimates for the tail index. If the spatial dependency is estimated individually, the uncertainties will be large. Furthermore, in the case of joint return level is of interest, taking into accounts the spatial dependence properties will improve the estimation process.

  11. Spatial filtering with photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Maigyte, Lina [Departament de Física i Enginyeria Nuclear, Universitat Politècnica de Catalunya, Rambla Sant Nebridi 22, Terrassa 08222 (Spain); Staliunas, Kestutis [Departament de Física i Enginyeria Nuclear, Universitat Politècnica de Catalunya, Rambla Sant Nebridi 22, Terrassa 08222 (Spain); Institució Catalana de Recerca i Estudis Avançats (ICREA), Pg. Lluís Companys 23, Barcelona 08010 (Spain)

    2015-03-15

    Photonic crystals are well known for their celebrated photonic band-gaps—the forbidden frequency ranges, for which the light waves cannot propagate through the structure. The frequency (or chromatic) band-gaps of photonic crystals can be utilized for frequency filtering. In analogy to the chromatic band-gaps and the frequency filtering, the angular band-gaps and the angular (spatial) filtering are also possible in photonic crystals. In this article, we review the recent advances of the spatial filtering using the photonic crystals in different propagation regimes and for different geometries. We review the most evident configuration of filtering in Bragg regime (with the back-reflection—i.e., in the configuration with band-gaps) as well as in Laue regime (with forward deflection—i.e., in the configuration without band-gaps). We explore the spatial filtering in crystals with different symmetries, including axisymmetric crystals; we discuss the role of chirping, i.e., the dependence of the longitudinal period along the structure. We also review the experimental techniques to fabricate the photonic crystals and numerical techniques to explore the spatial filtering. Finally, we discuss several implementations of such filters for intracavity spatial filtering.

  12. Notes on the Spatial Turn

    Directory of Open Access Journals (Sweden)

    Stipe Grgas

    2012-06-01

    Full Text Available On the basis of ever-mounting evidence, amongst which is the “zone” problematic of the Zadar conference that occassioned these notes, it can be concluded that the spatial turn has insinuated itself as an all-pervading heuristic tool throughout the humanities and the social sciences. The extent to which space and spatiality have usurped the central stage in the various branches of reasearch can be gauged by admonishments that what we are witnessing is a new fundamentalism that has simply inverted the terms of the dualism of time and space (May and Thrift 2001: “Introduction”. According to Michael Dear the sway of space is manifested in multifold ways: in the ubiquity of spatial analysis in social theories and practices; in the explosion of publications devoted to the exploration of the interface of the social and the spatial; in the reintegration of human geography into various domains of knowledge; in the focus given to difference and the consequent diversification of theoretical and empirical practices; in a theoretically informed exploration of the relation between geographical knowledge and social action; and, finally, in the unprecedented proliferation of research agendas and publications pertaining to these isuuses (Dear 2001: 24. Two recent collections of papers are indicative of the ubiquity of spatial issues in scholarly work.

  13. Spatial vision in Bombus terrestris

    Directory of Open Access Journals (Sweden)

    Aravin eChakravarthi

    2016-02-01

    Full Text Available Bombus terrestris is one of the most commonly used insect models to investigate visually guided behavior and spatial vision in particular. Two fundamental measures of spatial vision are spatial resolution and contrast sensitivity. In this study, we report the threshold of spatial resolution in B. terrestris and characterize the contrast sensitivity function of the bumblebee visual system for a dual choice discrimination task. We trained bumblebees in a Y-maze experimental set-up to associate a vertical sinusoidal grating with a sucrose reward, and a horizontal grating with absence of a reward. Using a logistic psychometric function, we estimated a resolution threshold of 0.21 cycles deg-1 of visual angle. This resolution is in the same range but slightly lower than that found in honeybees (Apis mellifera and A. cerana and another bumblebee species (B. impatiens. We also found that the contrast sensitivity of B. terrestris was 1.57 for the spatial frequency 0.09 cycles deg-1 and 1.26. for 0.18 cycles deg-1.

  14. Spatialization of time in mian.

    Science.gov (United States)

    Fedden, Sebastian; Boroditsky, Lera

    2012-01-01

    We examine representations of time among the Mianmin of Papua New Guinea. We begin by describing the patterns of spatial and temporal reference in Mian. Mian uses a system of spatial terms that derive from the orientation and direction of the Hak and Sek rivers and the surrounding landscape. We then report results from a temporal arrangement task administered to a group of Mian speakers. The results reveal evidence for a variety of temporal representations. Some participants arranged time with respect to their bodies (left to right or toward the body). Others arranged time as laid out on the landscape, roughly along the east/west axis (either east to west or west to east). This absolute pattern is consistent both with the axis of the motion of the sun and the orientation of the two rivers, which provides the basis for spatial reference in the Mian language. The results also suggest an increase in left to right temporal representations with increasing years of formal education (and the reverse pattern for absolute spatial representations for time). These results extend previous work on spatial representations for time to a new geographical region, physical environment, and linguistic and cultural system.

  15. Spatialization of time in Mian

    Directory of Open Access Journals (Sweden)

    Sebastian eFedden

    2012-11-01

    Full Text Available We examine representations of time among the Mianmin of Papua New Guinea. We begin by describing the patterns of spatial and temporal reference in Mian. Mian uses a system of spatial terms that derive from the orientation and direction of the Hak and Sek rivers and the surrounding landscape. We then report results from a temporal arrangement task administered to a group of Mian speakers. The results reveal evidence for a variety of temporal representations. Some participants arranged time with respect to their bodies (left to right or toward the body. Others arranged time as laid out on the landscape, roughly along the east/west axis (either east to west or west to east. This absolute pattern is consistent both with the axis of the motion of the sun and the orientation of the two rivers, which provides the basis for spatial reference in the Mian language. The results also suggest an increase in left-to-right temporal representations with increasing years of formal education (and the reverse pattern for absolute spatial representations for time. These results extend previous work on spatial representations for time to a new geographical region, physical environment, and linguistic and cultural system.

  16. How Attention Affects Spatial Resolution

    Science.gov (United States)

    Carrasco, Marisa; Barbot, Antoine

    2015-01-01

    We summarize and discuss a series of psychophysical studies on the effects of spatial covert attention on spatial resolution, our ability to discriminate fine patterns. Heightened resolution is beneficial in most, but not all, visual tasks. We show how endogenous attention (voluntary, goal driven) and exogenous attention (involuntary, stimulus driven) affect performance on a variety of tasks mediated by spatial resolution, such as visual search, crowding, acuity, and texture segmentation. Exogenous attention is an automatic mechanism that increases resolution regardless of whether it helps or hinders performance. In contrast, endogenous attention flexibly adjusts resolution to optimize performance according to task demands. We illustrate how psychophysical studies can reveal the underlying mechanisms of these effects and allow us to draw linking hypotheses with known neurophysiological effects of attention. PMID:25948640

  17. The spatial dimensions of innovation

    DEFF Research Database (Denmark)

    Lorentzen, Anne

    2005-01-01

    The paper discusseses the spatial dimensions of innovation in Polish manufacturing companies. The conceptual framework of the paper is an understanding of social networks as a potential resource of the company, whether they are internal or external. Whether the company benefits from the potential...... of the networks (local, national international). Finally how can the network strategy of the companies be explained? What factors seem to determine an active involvement of networks and what other factors seem to explain a self-sufficient strategy of innovation? What is the spatial extension of the networks......, and are there systematic differences in the spatial extension of the networks? Does the transitional situation of the Polish society seem to favour certain strategies of innovation?...

  18. Beyond Space For Spatial Networks

    CERN Document Server

    Expert, Paul; Blondel, Vincent D; Lambiotte, Renaud

    2010-01-01

    Many complex systems are organized in the form of a network embedded in space. Important examples include the physical Internet infrastucture, road networks, flight connections, brain functional networks and social networks. The effect of space on network topology has recently come under the spotlight because of the emergence of pervasive technologies based on geo-localization, which constantly fill databases with people's movements and thus reveal their trajectories and spatial behaviour. Extracting patterns and regularities from the resulting massive amount of human mobility data requires the development of appropriate tools for uncovering information in spatially-embedded networks. In contrast with most works that tend to apply standard network metrics to any type of network, we argue in this paper for a careful treatment of the constraints imposed by space on network topology. In particular, we focus on the problem of community detection and propose a modularity function adapted to spatial networks. We sh...

  19. Spatial Sampling Design for Estimating Regional GPP With Spatial Heterogeneities

    NARCIS (Netherlands)

    Wang, J.H.; Ge, Y.; Heuvelink, G.B.M.; Zhou, C.H.

    2014-01-01

    The estimation of regional gross primary production (GPP) is a crucial issue in carbon cycle studies. One commonly used way to estimate the characteristics of GPP is to infer the total amount of GPP by collecting field samples. In this process, the spatial sampling design will affect the error

  20. Continuous Spatial Process Models for Spatial Extreme Values

    KAUST Repository

    Sang, Huiyan

    2010-01-28

    We propose a hierarchical modeling approach for explaining a collection of point-referenced extreme values. In particular, annual maxima over space and time are assumed to follow generalized extreme value (GEV) distributions, with parameters μ, σ, and ξ specified in the latent stage to reflect underlying spatio-temporal structure. The novelty here is that we relax the conditionally independence assumption in the first stage of the hierarchial model, an assumption which has been adopted in previous work. This assumption implies that realizations of the the surface of spatial maxima will be everywhere discontinuous. For many phenomena including, e. g., temperature and precipitation, this behavior is inappropriate. Instead, we offer a spatial process model for extreme values that provides mean square continuous realizations, where the behavior of the surface is driven by the spatial dependence which is unexplained under the latent spatio-temporal specification for the GEV parameters. In this sense, the first stage smoothing is viewed as fine scale or short range smoothing while the larger scale smoothing will be captured in the second stage of the modeling. In addition, as would be desired, we are able to implement spatial interpolation for extreme values based on this model. A simulation study and a study on actual annual maximum rainfall for a region in South Africa are used to illustrate the performance of the model. © 2009 International Biometric Society.

  1. Spatial Sampling Design for Estimating Regional GPP With Spatial Heterogeneities

    NARCIS (Netherlands)

    Wang, J.H.; Ge, Y.; Heuvelink, G.B.M.; Zhou, C.H.

    2014-01-01

    The estimation of regional gross primary production (GPP) is a crucial issue in carbon cycle studies. One commonly used way to estimate the characteristics of GPP is to infer the total amount of GPP by collecting field samples. In this process, the spatial sampling design will affect the error varia

  2. Maritime Spatial Planning in Cyprus

    OpenAIRE

    Hadjimitsis Diofantos; Agapiou Athos; Themistocleous Kyriakos; Mettas Christodoulos; Evagorou Evagoras; Soulis Giorgos; Xagoraris Zafeiris; Pilikou Maria; Aliouris Kyriakos; Ioannou Nicolas

    2016-01-01

    Spatial Planning is a critical tool for land management and is extensively used in all developed nations. The Marine Spatial Planning (MSP), at the European Union (EU) level, is based on Directive 2014/89/EU of the European Parliament and Council of 23rd July 2014 which establishes a common framework for MSP in the EU, which each Member State is called to apply in relation to the maritime space under its jurisdiction (marine waters). In this paper the overall results from the “Cross-Border Co...

  3. Fundamentals of spatial information systems

    CERN Document Server

    Laurini, Robert

    1992-01-01

    The study and application of spatial information systems have been developed primarily from the use of computers in the geosciences. These systems have the principle functions of capturing, storing, representing, manipulating, and displaying data in 2-D and 3-D worlds. This book approaches its subject from the perspectives of informatics and geography, presenting methods of conceptual modeling developed in computer science that provide valuable aids for resolving spatial problems. This book is an essential textbook for both students and practitioners. It is indispensable for academic geographe

  4. Spectral Methods in Spatial Statistics

    Directory of Open Access Journals (Sweden)

    Kun Chen

    2014-01-01

    Full Text Available When the spatial location area increases becoming extremely large, it is very difficult, if not possible, to evaluate the covariance matrix determined by the set of location distance even for gridded stationary Gaussian process. To alleviate the numerical challenges, we construct a nonparametric estimator called periodogram of spatial version to represent the sample property in frequency domain, because periodogram requires less computational operation by fast Fourier transform algorithm. Under some regularity conditions on the process, we investigate the asymptotic unbiasedness property of periodogram as estimator of the spectral density function and achieve the convergence rate.

  5. Optimization of spatial complex networks

    Science.gov (United States)

    Guillier, S.; Muñoz, V.; Rogan, J.; Zarama, R.; Valdivia, J. A.

    2017-02-01

    First, we estimate the connectivity properties of a predefined (fixed node locations) spatial network which optimizes a connectivity functional that balances construction and transportation costs. In this case we obtain a Gaussian distribution for the connectivity. However, when we consider these spatial networks in a growing process, we obtain a power law distribution for the connectivity. If the transportation costs in the functional involve the shortest geometrical path, we obtain a scaling exponent γ = 2.5. However, if the transportation costs in the functional involve just the shortest path, we obtain γ = 2.2. Both cases may be useful to analyze in some real networks.

  6. Spatial data quality: from description to application

    NARCIS (Netherlands)

    Oort, van P.A.J.

    2006-01-01

    The growing availability of spatial data along with growing ease to use the spatial data (thanks to wide-scale adoption of GIS) have made it possible to use spatial data in applications inappropriate considering the quality of the data. As a result, concerns about spatial data quality have

  7. Spatial data management for WebGIS

    Institute of Scientific and Technical Information of China (English)

    钟志农; 景宁; 陈荦; 吴秋云

    2004-01-01

    Spatial data management is an important factor that affects the performance of WebGIS. In this paper, spatial data management for WebGIS is discussed from two aspects: spatial data model and data storage. Current data models and storage methods are analyzed and compared. According to the requirements of spatial data management for WebGIS,a spatial data model is proposed, which organizes spatial data in four levels: geometry, feature, layer and map. Based on this model, spatial data are managed and stored in object-relational database management system (ORDBMS).

  8. The neoliberalisation of strategic spatial planning

    DEFF Research Database (Denmark)

    Olesen, Kristian

    2014-01-01

    Strategic spatial planning practices have recently taken a neoliberal turn in many northwestern European countries. This neoliberalisation of strategic spatial planning has materialised partly in governance reforms aiming to reduce or abolish strategic spatial planning at national and regional...... scales, and partly through the normalisation of neoliberal discourses in strategic spatial planning processes. This paper analyses the complex relationship, partly of unease and partly of coevolution, between neoliberalism and strategic spatial planning. Furthermore, the paper discusses the key...... challenges for strategic spatial planning in the face of neoliberalism and argues for a need to strengthen strategic spatial planning’s critical dimension....

  9. A New Methodology of Spatial Crosscorrelation Analysis

    CERN Document Server

    Chen, Yanguang

    2015-01-01

    The idea of spatial crosscorrelation was conceived of long ago. However, unlike the related spatial autocorrelation, the theory and method of spatial crosscorrelation analysis have remained undeveloped. This paper presents a set of models and working methods for spatial crosscorrelation analysis. By analogy with Moran's index newly expressed in a spatial quadratic form and by means of mathematical reasoning, I derive a theoretical framework for geographical crosscorrelation analysis. First, two sets of spatial crosscorrelation coefficients are defined, including a global spatial crosscorrelation coefficient and a set of local spatial crosscorrelation coefficients. Second, a pair of scatterplots of spatial crosscorrelation is proposed, and different scatterplots show different relationships between correlated variables. Based on the spatial crosscorrelation coefficient, Pearson's correlation coefficient can be decomposed into two parts: direct correlation (partial crosscorrelation) and indirect correlation (sp...

  10. Learning Anatomy Enhances Spatial Ability

    Science.gov (United States)

    Vorstenbosch, Marc A. T. M.; Klaassen, Tim P. F. M.; Donders, A. R. T.; Kooloos, Jan G. M.; Bolhuis, Sanneke M.; Laan, Roland F. J. M.

    2013-01-01

    Spatial ability is an important factor in learning anatomy. Students with high scores on a mental rotation test (MRT) systematically score higher on anatomy examinations. This study aims to investigate if learning anatomy also oppositely improves the MRT-score. Five hundred first year students of medicine ("n" = 242, intervention) and…

  11. Spatial Reasoning for Image Retrieval

    NARCIS (Netherlands)

    Aiello, Marco; Areces, Carlos; Rijke, Maarten de

    1999-01-01

    Building upon the previously introduced description logic of concrete domains, we provide a system which is aimed at enhancing image retrieval with the ability to perform spatial reasoning. In this early stage of our research we focus on obtaining a formalism which is expressive enough to increase t

  12. Learning Anatomy Enhances Spatial Ability

    Science.gov (United States)

    Vorstenbosch, Marc A. T. M.; Klaassen, Tim P. F. M.; Donders, A. R. T.; Kooloos, Jan G. M.; Bolhuis, Sanneke M.; Laan, Roland F. J. M.

    2013-01-01

    Spatial ability is an important factor in learning anatomy. Students with high scores on a mental rotation test (MRT) systematically score higher on anatomy examinations. This study aims to investigate if learning anatomy also oppositely improves the MRT-score. Five hundred first year students of medicine ("n" = 242, intervention) and…

  13. Competition in spatial location models

    NARCIS (Netherlands)

    Webers, H.M.

    1996-01-01

    Models of spatial competition are designed and analyzed to describe the fact that space, by its very nature, is a source of market power. This field of research, lying at the interface of game theory and economics, has attracted much interest because location problems are related to many aspects of

  14. Competition in spatial location models

    NARCIS (Netherlands)

    Webers, H.M.

    1996-01-01

    Models of spatial competition are designed and analyzed to describe the fact that space, by its very nature, is a source of market power. This field of research, lying at the interface of game theory and economics, has attracted much interest because location problems are related to many aspects of

  15. Learning anatomy enhances spatial ability.

    NARCIS (Netherlands)

    Vorstenbosch, M.A.T.M.; Klaassen, T.P.; Donders, A.R.T.; Kooloos, J.G.M.; Bolhuis, S.M.; Laan, R.F.J.M.

    2013-01-01

    Spatial ability is an important factor in learning anatomy. Students with high scores on a mental rotation test (MRT) systematically score higher on anatomy examinations. This study aims to investigate if learning anatomy also oppositely improves the MRT-score. Five hundred first year students of me

  16. Spatial correlations in attribute communities.

    Directory of Open Access Journals (Sweden)

    Federica Cerina

    Full Text Available Community detection is an important tool for exploring and classifying the properties of large complex networks and should be of great help for spatial networks. Indeed, in addition to their location, nodes in spatial networks can have attributes such as the language for individuals, or any other socio-economical feature that we would like to identify in communities. We discuss in this paper a crucial aspect which was not considered in previous studies which is the possible existence of correlations between space and attributes. Introducing a simple toy model in which both space and node attributes are considered, we discuss the effect of space-attribute correlations on the results of various community detection methods proposed for spatial networks in this paper and in previous studies. When space is irrelevant, our model is equivalent to the stochastic block model which has been shown to display a detectability-non detectability transition. In the regime where space dominates the link formation process, most methods can fail to recover the communities, an effect which is particularly marked when space-attributes correlations are strong. In this latter case, community detection methods which remove the spatial component of the network can miss a large part of the community structure and can lead to incorrect results.

  17. Spatial Coherence of Tropical Rainfall

    Science.gov (United States)

    Ratan, Ram; Venugopal, V.; Sukhatme, Jai; Murtugudde, Raghu

    2014-05-01

    We characterise the spatial coherence of tropical rain and its wet spells from observations (TRMM) and assess if models (CMIP5) are able to reproduce the observed features. Based on 15 years (1998-2012) of TRMM 3B42 (V7) 1-degree, daily rainfall, we estimate the spatial decorrelation scale (e-folding distance) of rain at each location in the tropics. A ratio of zonal to meridional spatial scales clearly illustrates that while rain patterns tend to be anisotropic (ratio of 4) over tropical ocean regions (particularly over Pacific ITCZ); over land regions, rain tends to be mostly isotropic. This contrast between ocean and land appears to be reasonably well captured by CMIP5 models, although the anisotropy (ratio) over ocean is much higher than in observations. A very curious behaviour in observations is the presence of a coherent band of spatial decorrelation lengths straddling the equator, in the East Pacific, reminiscent of a double ITCZ that some models tend to simulate. A similar analysis of wet spells of different durations suggests that the decorrelation scale is largely independent of the duration of wet spell.

  18. Characterization of Spatial Memory Reconsolidation

    Science.gov (United States)

    De Jaeger, Xavier; Courtey, Julie; Brus, Maïna; Artinian, Julien; Villain, Hélène; Bacquié, Elodie; Roullet, Pascal

    2014-01-01

    Reconsolidation is necessary for the restabilization of reactivated memory traces. However, experimental parameters have been suggested as boundary conditions for this process. Here we investigated the role of a spatial memory trace's age, strength, and update on the reconsolidation process in mice. We first found that protein synthesis is…

  19. Spatial synchrony in cisco recruitment

    Science.gov (United States)

    Myers, Jared T.; Yule, Daniel L.; Jones, Michael L.; Ahrenstorff, Tyler D.; Hrabik, Thomas R.; Claramunt, Randall M.; Ebener, Mark P.; Berglund, Eric K.

    2015-01-01

    We examined the spatial scale of recruitment variability for disparate cisco (Coregonus artedi) populations in the Great Lakes (n = 8) and Minnesota inland lakes (n = 4). We found that the scale of synchrony was approximately 400 km when all available data were utilized; much greater than the 50-km scale suggested for freshwater fish populations in an earlier global analysis. The presence of recruitment synchrony between Great Lakes and inland lake cisco populations supports the hypothesis that synchronicity is driven by climate and not dispersal. We also found synchrony in larval densities among three Lake Superior populations separated by 25–275 km, which further supports the hypothesis that broad-scale climatic factors are the cause of spatial synchrony. Among several candidate climate variables measured during the period of larval cisco emergence, maximum wind speeds exhibited the most similar spatial scale of synchrony to that observed for cisco. Other factors, such as average water temperatures, exhibited synchrony on broader spatial scales, which suggests they could also be contributing to recruitment synchrony. Our results provide evidence that abiotic factors can induce synchronous patterns of recruitment for populations of cisco inhabiting waters across a broad geographic range, and show that broad-scale synchrony of recruitment can occur in freshwater fish populations as well as those from marine systems.

  20. Spatial auditory processing in pinnipeds

    Science.gov (United States)

    Holt, Marla M.

    Given the biological importance of sound for a variety of activities, pinnipeds must be able to obtain spatial information about their surroundings thorough acoustic input in the absence of other sensory cues. The three chapters of this dissertation address spatial auditory processing capabilities of pinnipeds in air given that these amphibious animals use acoustic signals for reproduction and survival on land. Two chapters are comparative lab-based studies that utilized psychophysical approaches conducted in an acoustic chamber. Chapter 1 addressed the frequency-dependent sound localization abilities at azimuth of three pinniped species (the harbor seal, Phoca vitulina, the California sea lion, Zalophus californianus, and the northern elephant seal, Mirounga angustirostris). While performances of the sea lion and harbor seal were consistent with the duplex theory of sound localization, the elephant seal, a low-frequency hearing specialist, showed a decreased ability to localize the highest frequencies tested. In Chapter 2 spatial release from masking (SRM), which occurs when a signal and masker are spatially separated resulting in improvement in signal detectability relative to conditions in which they are co-located, was determined in a harbor seal and sea lion. Absolute and masked thresholds were measured at three frequencies and azimuths to determine the detection advantages afforded by this type of spatial auditory processing. Results showed that hearing sensitivity was enhanced by up to 19 and 12 dB in the harbor seal and sea lion, respectively, when the signal and masker were spatially separated. Chapter 3 was a field-based study that quantified both sender and receiver variables of the directional properties of male northern elephant seal calls produce within communication system that serves to delineate dominance status. This included measuring call directivity patterns, observing male-male vocally-mediated interactions, and an acoustic playback study

  1. Spatial coherence of random laser emission.

    Science.gov (United States)

    Redding, Brandon; Choma, Michael A; Cao, Hui

    2011-09-01

    We experimentally studied the spatial coherence of random laser emission from dye solutions containing nanoparticles. The spatial coherence, measured in a double slit experiment, varied significantly with the density of scatterers and the size and shape of the excitation volume. A qualitative explanation is provided, illustrating the dramatic difference from the spatial coherence of a conventional laser. This work demonstrates that random lasers can be controlled to provide intense, spatially incoherent emission for applications in which spatial cross talk or speckle limit performance.

  2. Tourism versus spatial order: mutual relations

    OpenAIRE

    Meyer, Beata

    2012-01-01

    The relation between tourism and the spatial environment is characterized by mutual interaction. The proliferation of tourism and massive tourism development intensifies its impact on the spatial environment, yet the focus is usually placed on environmental degradation and the resulting distortion of spatial order. Concurrently, the significance of the spatial environment, and spatial order in particular, as one of the determinants of tourism development is understated. On a theoretical plane...

  3. Detection of Spatial Changes using Spatial Data Mining

    CERN Document Server

    Kodge, B G

    2011-01-01

    This paper uses the techniques of spatial data mining (SDM) and change detection (CD) in the field of geospatial information processing. Assuming the feasibility of discovering knowledge from spatial database and the demands of knowledge for change detection, the paper presents that change detection needs knowledge and technology of SDM should be integrated into applications of change detection. Special knowledge for change detection of linear feature, area feature and terrain are studied. Relationship between accuracy of change detection and errors of image registration is discussed. Change detection of linear feature, area feature and terrain based on SDM are investigated respectively. Change detection based on multivariate statistical analysis and training samples are analyzed. Land use/cover change detection based on SDM is discussed.

  4. A solution of spatial query processing and query optimization for spatial databases

    Institute of Scientific and Technical Information of China (English)

    YUAN Jie; XIE Kun-qing; MA Xiu-jun; ZHANG Min; SUN Le-bin

    2004-01-01

    Recently, attention has been focused on spatial query language which is used to query spatial databases. A design of spatial query language has been presented in this paper by extending the standard relational database query language SQL. It recognizes the significantly different requirements of spatial data handling and overcomes the inherent problems of the application of conventional database query languages. This design is based on an extended spatial data model, including the spatial data types and the spatial operators on them. The processing and optimization of spatial queries have also been discussed in this design. In the end, an implementation of this design is given in a spatial query subsystem.

  5. The Role of Spatial Ability and Strategy Preference for Spatial Problem Solving in Organic Chemistry

    Science.gov (United States)

    Stieff, Mike; Ryu, Minjung; Dixon, Bonnie; Hegarty, Mary

    2012-01-01

    In organic chemistry, spatial reasoning is critical for reasoning about spatial relationships in three dimensions and representing spatial information in diagrams. Despite its importance, little is known about the underlying cognitive components of spatial reasoning and the strategies that students employ to solve spatial problems in organic…

  6. The Role of Spatial Ability and Strategy Preference for Spatial Problem Solving in Organic Chemistry

    Science.gov (United States)

    Stieff, Mike; Ryu, Minjung; Dixon, Bonnie; Hegarty, Mary

    2012-01-01

    In organic chemistry, spatial reasoning is critical for reasoning about spatial relationships in three dimensions and representing spatial information in diagrams. Despite its importance, little is known about the underlying cognitive components of spatial reasoning and the strategies that students employ to solve spatial problems in organic…

  7. Purification of Spatial Tests: An IRT Analysis of Spatial and Reasoning Components in "Spatial" Tests.

    Science.gov (United States)

    Zimowski, Michele F.; Wothke, Werner

    Tests of spatial ability were analyzed for their analog (visuospatial) and nonanalog (verbal reasoning) components, using factor analyses of items and test scores. The self-selected sample consisted of over 2000 clients (average age about 26 or 27) employing the Johnson O'Connor Research Foundation's aptitude evaluation services in 12 metropolitan…

  8. Spatial frequency domain error budget

    Energy Technology Data Exchange (ETDEWEB)

    Hauschildt, H; Krulewich, D

    1998-08-27

    The aim of this paper is to describe a methodology for designing and characterizing machines used to manufacture or inspect parts with spatial-frequency-based specifications. At Lawrence Livermore National Laboratory, one of our responsibilities is to design or select the appropriate machine tools to produce advanced optical and weapons systems. Recently, many of the component tolerances for these systems have been specified in terms of the spatial frequency content of residual errors on the surface. We typically use an error budget as a sensitivity analysis tool to ensure that the parts manufactured by a machine will meet the specified component tolerances. Error budgets provide the formalism whereby we account for all sources of uncertainty in a process, and sum them to arrive at a net prediction of how "precisely" a manufactured component can meet a target specification. Using the error budget, we are able to minimize risk during initial stages by ensuring that the machine will produce components that meet specifications before the machine is actually built or purchased. However, the current error budgeting procedure provides no formal mechanism for designing machines that can produce parts with spatial-frequency-based specifications. The output from the current error budgeting procedure is a single number estimating the net worst case or RMS error on the work piece. This procedure has limited ability to differentiate between low spatial frequency form errors versus high frequency surface finish errors. Therefore the current error budgeting procedure can lead us to reject a machine that is adequate or accept a machine that is inadequate. This paper will describe a new error budgeting methodology to aid in the design and characterization of machines used to manufacture or inspect parts with spatial-frequency-based specifications. The output from this new procedure is the continuous spatial frequency content of errors that result on a machined part. If the machine

  9. Seroprevalencia de hantavirus en roedores y casos humanos en el sur de la Argentina Hantavirus seroprevalence in rodents and human cases in southern Argentina

    Directory of Open Access Journals (Sweden)

    Edmundo Larrieu

    2003-04-01

    Full Text Available En la Provincia de Río Negro, Argentina, se presentaron casos humanos de síndrome pulmonar por hantavirus (SPH en la región de la cordillera andino patagónica. El virus Andes ha sido identificado en la región, tanto en el roedor Oligoryzomys longicaudatus como en seres humanos, demostrándose la transmisión principalmente del roedor al hombre y la factibilidad de la transmisión de persona a persona. El objetivo del presente trabajo es presentar nueva información sobre especies de roedores portadores de hantavirus en Argentina, su prevalencia de anticuerpos para hantavirus (período 1999-2001 y la relación del tamaño de las poblaciones de roedores y su seroprevalencia con la ocurrencia de casos humanos (período 1996-2001. Para ello, se procedió a la colocación de 3973 trampas para captura viva de roedores, tipo sherman en seis operativos efectuados entre octubre de 1999 y mayo de 2001. Se obtuvieron muestras de sangre de los roedores las que fueron procesadas mediante enzimoinmunoensayo con antígenos elaborados a partir de virus Andes. Una síntesis de los resultados indica 397 roedores capturados, con un éxito de trampeo del 10% y una prevalencia de anticuerpos contra hantavirus del 1.0%. Se observaron importantes diferencias en las especies capturadas en cada una de las regiones. Se capturaron O. longicaudatus y A. Olivaceus seropositivos y O. flavescens y C. Laucha potencialmente portadores de hantavirus Se registraron 6 casos humanos en el período 1993-1995 (correspondientes a estudios retrospectivos, 21 casos se notificaron en el período 1996-1998 y 6 en el período 1999-2001 Se analiza la correlación entre ocurrencia de casos humanos, seroprevalencia en roedores y éxito de trampeo.In the Province of Río Negro, Argentina, human cases of hantavirus pulmonary syndrome (HPS have occurred in the region of the Patagonian Andean range. The Andes virus has been identified in the region, both in the rodent Oligoryzomys

  10. Representation Elements of Spatial Thinking

    Science.gov (United States)

    Fiantika, F. R.

    2017-04-01

    This paper aims to add a reference in revealing spatial thinking. There several definitions of spatial thinking but it is not easy to defining it. We can start to discuss the concept, its basic a forming representation. Initially, the five sense catch the natural phenomenon and forward it to memory for processing. Abstraction plays a role in processing information into a concept. There are two types of representation, namely internal representation and external representation. The internal representation is also known as mental representation; this representation is in the human mind. The external representation may include images, auditory and kinesthetic which can be used to describe, explain and communicate the structure, operation, the function of the object as well as relationships. There are two main elements, representations properties and object relationships. These elements play a role in forming a representation.

  11. Quality of Spatial Entanglement Propagation

    CERN Document Server

    Reichert, Matthew; Fleischer, Jason W

    2016-01-01

    We explore, both experimentally and theoretically, the propagation dynamics of spatially entangled photon pairs (biphotons). Characterization of entanglement is done via the Schmidt number, which is a universal measurement of the degree of entanglement directly related to the non-separability of the state into its subsystems. We develop expressions for the terms of the Schmidt number that depend on the amplitude and phase of the commonly used double-Gaussian approximation for the biphoton wave function, and demonstrate migration of entanglement between amplitude and phase upon propagation. We then extend this analysis to incorporate both phase curvature in the pump beam and higher spatial frequency content of more realistic non-Gaussian wave functions. Specifically, we generalize the classical beam quality parameter $M^2$ to the biphotons, allowing the description of more information-rich beams and more complex dynamics. Agreement is found with experimental measurements using direct imaging and Fourier optics...

  12. Swarm-Based Spatial Sorting

    CERN Document Server

    Amos, Martyn

    2008-01-01

    Purpose: To present an algorithm for spatially sorting objects into an annular structure. Design/Methodology/Approach: A swarm-based model that requires only stochastic agent behaviour coupled with a pheromone-inspired "attraction-repulsion" mechanism. Findings: The algorithm consistently generates high-quality annular structures, and is particularly powerful in situations where the initial configuration of objects is similar to those observed in nature. Research limitations/implications: Experimental evidence supports previous theoretical arguments about the nature and mechanism of spatial sorting by insects. Practical implications: The algorithm may find applications in distributed robotics. Originality/value: The model offers a powerful minimal algorithmic framework, and also sheds further light on the nature of attraction-repulsion algorithms and underlying natural processes.

  13. Urban Design and Spatial Equity

    DEFF Research Database (Denmark)

    Silva, Victor

    2012-01-01

    During the last century, the motorized vehicles have been preponderant in the streets. However, the emergence of the debate about sustainability and its relation to the urban environment has influenced urban designers to rethink the role of the streets and their spatiality. Pedestrians and cyclists...... are gaining space not only for move to a specific destination, but also space in which to play and stay. Taking in consideration the formal structure of our cities, streets are critical to urban transformation and strategic to restructure the urban flows and the quality of urban life. This chapter aims...... to explore and discuss the shared spatiality as a design strategy to enhance street life and non motorized modes of transportation. This research is part of a project titled Bikeability – funded by the Danish Research Council. The overall purpose of the Bikeability project is to investigate and document...

  14. Spatial Patterns in Urban Systems

    CERN Document Server

    Huynh, Hoai Nguyen; Legara, Erika Fille; Monterola, Christopher; Chew, Lock Yue

    2016-01-01

    Understanding the morphology of an urban system is an important step toward unveiling the dynamical processes of its growth and development. At the foundation of every urban system, transportation system is undeniably a crucial component in powering the life of the entire urban system. In this work, we study the spatial pattern of $73$ cities across the globe by analysing the distribution of public transport points within the cities. The analysis reveals that different spatial distributions of points could be classified into four groups with distinct features, indicating whether the points are clustered, dispersed or regularly distributed. From visual inspection, we observe that the cities with regularly distributed patterns do not have apparent centre in contrast to the other two types in which star-node structure, i.e. monocentric, can be clearly observed. Furthermore, the results provide evidence for the existence of two different types of urban system: well-planned and organically grown. We also study the...

  15. Sustainable Development and Spatial Inhomogeneities

    Science.gov (United States)

    Weisbuch, Gérard

    2013-05-01

    Historical data, theory and computer simulations support a connection between growth and economic inequality. Our present world with large regional differences in economic activity is a result of fast economic growth during the last two centuries. Because of limits to growth we might expect a future world to develop differently with far less growth. The question that we here address is: "Would a world with a sustainable economy be less unequal?" We then develop integrated spatial economic models based on limited resources consumption and technical knowledge accumulation and study them by the way of computer simulations. When the only coupling between world regions is diffusion we do not observe any spatial unequality. By contrast, highly localized economic activities are maintained by global market mechanisms. Structures sizes are determined by transportation costs. Wide distributions of capital and production are also predicted in this regime.

  16. Spatial discrimination and visual discrimination

    DEFF Research Database (Denmark)

    Haagensen, Annika M. J.; Grand, Nanna; Klastrup, Signe

    2013-01-01

    Two methods investigating learning and memory in juvenile Gottingen minipigs were evaluated for potential use in preclinical toxicity testing. Twelve minipigs were tested using a spatial hole-board discrimination test including a learning phase and two memory phases. Five minipigs were tested...... in a visual discrimination test. The juvenile minipigs were able to learn the spatial hole-board discrimination test and showed improved working and reference memory during the learning phase. Performance in the memory phases was affected by the retention intervals, but the minipigs were able to remember...... the concept of the test in both memory phases. Working memory and reference memory were significantly improved in the last trials of the memory phases. In the visual discrimination test, the minipigs learned to discriminate between the three figures presented to them within 9-14 sessions. For the memory test...

  17. Spatial Hearing in Echoic Environments

    Science.gov (United States)

    2008-02-29

    target from masker and thereby support selective attention. (Published in 2005 in Acta Acustica united with Acustica [J3]) A paper was published...localization. (Published in 2008 in Acta Acustica united with Acustica [J10]) Interest in the perceptual consequences of reverberation on perception...E Larson and Satyavarta (2005). “Top-down and bottom-up influences on spatial unmasking,” Acta Acustica united with Acustica . [J4] Naka, Y, A

  18. Multichannel spatial surround sound system

    Institute of Scientific and Technical Information of China (English)

    RAO Dan; XIE Bosun

    2004-01-01

    Based on the consideration of being compatible with 5.1 channel horizontal surround sound system, a spatial surround sound system is proposed. Theoretical and experimental results show that the system has a wide listening area. It can not only recreate stable image in the front and rear direction, but also eliminate the defect of poor lateral image of 5.1 channel system. The system can be used to reproduce special 3D sound effect and the spaciousness of hall.

  19. Symbol Recognition using Spatial Relations

    OpenAIRE

    K.C., Santosh; Lamiroy, Bart; Wendling, Laurent

    2012-01-01

    International audience; In this paper, we present a method for symbol recognition based on the spatio-structural description of a 'vocabulary' of extracted visual elementary parts. It is applied to symbols in electrical wiring diagrams. The method consists of first identifying vocabulary elements into different groups based on their types (e.g., circle, corner ). We then compute spatial relations between the possible pairs of labelled vocabulary types which are further used as a basis for bui...

  20. Spatial Light Rebroadcaster Architecture Study

    Science.gov (United States)

    1992-12-01

    linear photo-diode array (input side of spatial light rebroadcaster). Additional raytraces are shown in Fig. 3.2-3. The mask layout is shown in Fig...actual optical system use optical raytracing design 3 software. The literature generally shows only very simplified, schematic drawings of cylindrical...with low contrast irnfrared images and I speckled radar images. It has also been employed extensively in medicai image processing to, for example

  1. Mechanisms for Human Spatial Competence

    Science.gov (United States)

    2007-01-01

    experience. To take a famous example from Stevens & Coupe [43], when studying a map of the United States, San Diego will tend to be encoded with respect to...Relations. Cognitive Psychology 18, 87–121 (1986) 43. Stevens , A., Coupe, P.: Distortions in Judged Spatial Relations. Cognitive Psychology 10, 422...Model of Human Attentional Networks. Cognitive Systems Research 5, 119–134 (2004) 60. Finke, R.A., Pinker , S., Farah, M.: Reinterpreting Visual

  2. Gender Structure and Spatial Organization

    Directory of Open Access Journals (Sweden)

    Minoosh Sadoughianzadeh

    2013-11-01

    Full Text Available As a contribution to the widespread debate on the “gender reading” of the “built environment,” this article aims to situate the subject in a new context, the Iranian society. To depict the subject, two distinct traditional architectures of the region, associated with their respective socio-spatial organizations, have been comparatively explored: the “Introvert” and “Extrovert.” These two almost ageless “Introvert” and “Extrovert” architectures, evolved through centuries in different geographical parts of the country, are spatial patterns aptly illustrating how the “gender structure” of each social organization has contributed to the formation of the relevant “physical space” and, further, how the specific “gender relationships” are pertinently structured within each one of the two types of the spaces. Based on a systematic approach and through concentration on the macro-socio-spatial organization, this article is to explore the gender/space associated variations within either of the social systems they belong to. This perspective is particularly instrumental in pinpointing the Introvert and Extrovert architectures in the context of their social organizations and carefully scrutinizing “gender” and “space” categories as systematically integrated variables.

  3. Maritime Spatial Planning in Cyprus

    Directory of Open Access Journals (Sweden)

    Hadjimitsis Diofantos

    2016-01-01

    Full Text Available Spatial Planning is a critical tool for land management and is extensively used in all developed nations. The Marine Spatial Planning (MSP, at the European Union (EU level, is based on Directive 2014/89/EU of the European Parliament and Council of 23rd July 2014 which establishes a common framework for MSP in the EU, which each Member State is called to apply in relation to the maritime space under its jurisdiction (marine waters. In this paper the overall results from the “Cross-Border Cooperation for the development of Marine Spatial Planning” project are presented for the area of Cyprus. A variety of activities fall within the MSP such as maritime transport routes and traffic flows, exploration, exploitation and extraction of energy resources, tourism, underwater cultural heritage etc. In addition, the legal framework, activities maps are also shown. The variety of conflicts maps for the area of Limassol are illustrated both in 2D and 3D. A hypothetical scenario of Limassol town in Cyprus as an energy center is presented based on the overall results. The paper ends with some conclusions regarding the framework of MSP in Cyprus.

  4. Maritime Spatial Planning in Cyprus

    Science.gov (United States)

    Hadjimitsis, Diofantos; Agapiou, Athos; Themistocleous, Kyriakos; Mettas, Christodoulos; Evagorou, Evagoras; Soulis, Giorgos; Xagoraris, Zafeiris; Pilikou, Maria; Aliouris, Kyriakos; Ioannou, Nicolas

    2016-01-01

    Spatial Planning is a critical tool for land management and is extensively used in all developed nations. The Marine Spatial Planning (MSP), at the European Union (EU) level, is based on Directive 2014/89/EU of the European Parliament and Council of 23rd July 2014 which establishes a common framework for MSP in the EU, which each Member State is called to apply in relation to the maritime space under its jurisdiction (marine waters). In this paper the overall results from the "Cross-Border Cooperation for the development of Marine Spatial Planning" project are presented for the area of Cyprus. A variety of activities fall within the MSP such as maritime transport routes and traffic flows, exploration, exploitation and extraction of energy resources, tourism, underwater cultural heritage etc. In addition, the legal framework, activities maps are also shown. The variety of conflicts maps for the area of Limassol are illustrated both in 2D and 3D. A hypothetical scenario of Limassol town in Cyprus as an energy center is presented based on the overall results. The paper ends with some conclusions regarding the framework of MSP in Cyprus.

  5. Deep Mapping and Spatial Anthropology

    Directory of Open Access Journals (Sweden)

    Les Roberts

    2016-01-01

    Full Text Available This paper provides an introduction to the Humanities Special Issue on “Deep Mapping”. It sets out the rationale for the collection and explores the broad-ranging nature of perspectives and practices that fall within the “undisciplined” interdisciplinary domain of spatial humanities. Sketching a cross-current of ideas that have begun to coalesce around the concept of “deep mapping”, the paper argues that rather than attempting to outline a set of defining characteristics and “deep” cartographic features, a more instructive approach is to pay closer attention to the multivalent ways deep mapping is performatively put to work. Casting a critical and reflexive gaze over the developing discourse of deep mapping, it is argued that what deep mapping “is” cannot be reduced to the otherwise a-spatial and a-temporal fixity of the “deep map”. In this respect, as an undisciplined survey of this increasing expansive field of study and practice, the paper explores the ways in which deep mapping can engage broader discussion around questions of spatial anthropology.

  6. Spatial complexity in children's language.

    Science.gov (United States)

    Weist, R M; Lymburner, N L; Piotrowski, S; Stoddard, J L

    2000-10-01

    The purpose of this research was to explore the properties of locative scenes which influence the sequence of the acquisition of spatial prepositions in English. Children ranging in age from about 2;8 to 5;6 were tested with a comprehension test involving a sentence-picture matching task. The comprehension test contained six kinds of spatial contrasts which were judged to vary in the geometric complexity of the scene. The order of acquisition was as follows: (1) into/out of & onto/off of, (2) in/on, (3) into/onto & out of/off of and through/over (around), (4) between X & Y/Y & Z, and (5) across/along. Complexity depends on a number of factors such as the number of referent objects and the nature of the relationship between the object to be located and the critical feature of the referent object. Prepositions which involve a more complex spatial geometry are more difficult for young children to comprehend. It was argued that the sequence of acquisition is partially determined by the course of conceptual development.

  7. Spatial Reasoning in Tenejapan Mayans

    Science.gov (United States)

    Li, Peggy; Abarbanell, Linda; Gleitman, Lila; Papafragou, Anna

    2011-01-01

    Language communities differ in their stock of reference frames (coordinate systems for specifying locations and directions). English typically uses egocentrically defined axes (e.g., “left-right”), especially when describing small-scale relationships. Other languages such as Tseltal Mayan prefer to use geocentrically-defined axes (e.g., “north-south”) and do not use any type of projective body-defined axes. It has been argued that the availability of specific frames of reference in language determines the availability or salience of the corresponding spatial concepts. In four experiments, we explored this hypothesis by testing Tseltal speakers’ spatial reasoning skills. Whereas most prior tasks in this domain were open-ended (allowing several correct solutions), the present tasks required a unique solution that favored adopting a frame of reference that was either congruent or incongruent with what is habitually lexicalized in the participants’ language. In these tasks, Tseltal speakers easily solved the language-incongruent problems, and performance was generally more robust for these than for the language-congruent problems that favored geocentrically-defined coordinates. We suggest thatlisteners’ probabilistic inferences when instruction is open to more than one interpretation account for why there are greater cross-linguistic differences in the solutions to open-ended spatial problems than to less ambiguous ones. PMID:21481854

  8. Factors affecting tactile spatial acuity.

    Science.gov (United States)

    Craig, J C; Kisner, J M

    1998-01-01

    Tactile spatial acuity on the fingerpad was measured using a grating orientation task. In this task, subjects are required to identify the orientation of square-wave gratings placed on the skin. Previous studies have shown that performance varies as a function of the width of the grooves in the gratings. In the present study, both groove width and the overall size and configuration of the contactors were varied. Sensitivity improved with wider grooves and with larger contactors. Additional measurements showed that the improved sensitivity is not the result of the increase in total area contacted, but rather is due to two other factors associated with larger contactors. One is the greater linear extent of the larger contactors. The other appears to be due to the reduction in the interference produced by the outer edge of the contactor. Specifically, as the contactor increases in size, the distance between the outer edge and the center portion of the grooves also increases. It was also shown that subjects are more sensitive to a single, continuous groove as compared with two grooves of the same total length but spatially discontinuous. Similarly, subjects are more sensitive to a contactor with a continuous groove than to a contactor in which just the end points of the groove are presented. The results are generally consistent with the results of peripheral, neurophysiological recordings. The results are discussed in terms of the way in which both spatial and intensive factors may affect sensitivity to grating orientation.

  9. Bootstrap percolation on spatial networks

    Science.gov (United States)

    Gao, Jian; Zhou, Tao; Hu, Yanqing

    2015-10-01

    Bootstrap percolation is a general representation of some networked activation process, which has found applications in explaining many important social phenomena, such as the propagation of information. Inspired by some recent findings on spatial structure of online social networks, here we study bootstrap percolation on undirected spatial networks, with the probability density function of long-range links’ lengths being a power law with tunable exponent. Setting the size of the giant active component as the order parameter, we find a parameter-dependent critical value for the power-law exponent, above which there is a double phase transition, mixed of a second-order phase transition and a hybrid phase transition with two varying critical points, otherwise there is only a second-order phase transition. We further find a parameter-independent critical value around -1, about which the two critical points for the double phase transition are almost constant. To our surprise, this critical value -1 is just equal or very close to the values of many real online social networks, including LiveJournal, HP Labs email network, Belgian mobile phone network, etc. This work helps us in better understanding the self-organization of spatial structure of online social networks, in terms of the effective function for information spreading.

  10. Plasticity of human spatial cognition: Spatial language and cognition covary across cultures

    NARCIS (Netherlands)

    Haun, D.B.M.; Rapold, C.J.; Janzen, G.; Levinson, S.C.

    2011-01-01

    The present paper explores cross-cultural variation in spatial cognition by comparing spatial reconstruction tasks by Dutch and Namibian elementary school children. These two communities differ in the way they predominantly express spatial relations in language. Four experiments investigate

  11. Spatial eigenvector filtering for spatiotemporal crime mapping and spatial crime analysis

    NARCIS (Netherlands)

    Helbich, M; Jokar Arsanjani, J

    2015-01-01

    Spatial and spatiotemporal analyses are exceedingly relevant to determine criminogenic factors. The estimation of Poisson and negative binomial models (NBM) is complicated by spatial autocorrelation. Therefore, first, eigenvector spatial filtering (ESF) is introduced as a method for spatiotemporal m

  12. Spatial Data Mining using Cluster Analysis

    Directory of Open Access Journals (Sweden)

    Ch.N.Santhosh Kumar

    2012-09-01

    Full Text Available Data mining, which is refers to as Knowledge Discovery in Databases(KDD, means a process of nontrivialexaction of implicit, previously useful and unknown information such as knowledge rules, descriptions,regularities, and major trends from large databases. Data mining is evolved in a multidisciplinary field ,including database technology, machine learning, artificial intelligence, neural network, informationretrieval, and so on. In principle data mining should be applicable to the different kind of data and databasesused in many different applications, including relational databases, transactional databases, datawarehouses, object- oriented databases, and special application- oriented databases such as spatialdatabases, temporal databases, multimedia databases, and time- series databases. Spatial data mining, alsocalled spatial mining, is data mining as applied to the spatial data or spatial databases. Spatial data are thedata that have spatial or location component, and they show the information, which is more complex thanclassical data. A spatial database stores spatial data represents by spatial data types and spatialrelationships and among data. Spatial data mining encompasses various tasks. These include spatialclassification, spatial association rule mining, spatial clustering, characteristic rules, discriminant rules,trend detection. This paper presents how spatial data mining is achieved using clustering.

  13. Explaining Spatial Homogamy. Compositional, Spatial and Regional Cultural Determinants of Regional Patterns of Spatial Homogamy in the Netherlands

    NARCIS (Netherlands)

    Haandrikman, Karen; van Wissen, Leo J. G.; Harmsen, Carel N.

    2011-01-01

    Spatial homogamy, or sharing a similarity in geographical origin, is an under-researched dimension in homogamy studies. In the Netherlands, people tend to choose spatially homogamous partners. Moreover, there is considerable regional variation in spatial homogamy, even when residential location and

  14. Estimating hantavirus risk in southern Argentina: a GIS-based approach combining human cases and host distribution.

    Science.gov (United States)

    Andreo, Veronica; Neteler, Markus; Rocchini, Duccio; Provensal, Cecilia; Levis, Silvana; Porcasi, Ximena; Rizzoli, Annapaola; Lanfri, Mario; Scavuzzo, Marcelo; Pini, Noemi; Enria, Delia; Polop, Jaime

    2014-01-14

    We use a Species Distribution Modeling (SDM) approach along with Geographic Information Systems (GIS) techniques to examine the potential distribution of hantavirus pulmonary syndrome (HPS) caused by Andes virus (ANDV) in southern Argentina and, more precisely, define and estimate the area with the highest infection probability for humans, through the combination with the distribution map for the competent rodent host (Oligoryzomys longicaudatus). Sites with confirmed cases of HPS in the period 1995-2009 were mostly concentrated in a narrow strip (~90 km × 900 km) along the Andes range from northern Neuquén to central Chubut province. This area is characterized by high mean annual precipitation (~1,000 mm on average), but dry summers (less than 100 mm), very low percentages of bare soil (~10% on average) and low temperatures in the coldest month (minimum average temperature -1.5 °C), as compared to the HPS-free areas, features that coincide with sub-Antarctic forests and shrublands (especially those dominated by the invasive plant Rosa rubiginosa), where rodent host abundances and ANDV prevalences are known to be the highest. Through the combination of predictive distribution maps of the reservoir host and disease cases, we found that the area with the highest probability for HPS to occur overlaps only 28% with the most suitable habitat for O. longicaudatus. With this approach, we made a step forward in the understanding of the risk factors that need to be considered in the forecasting and mapping of risk at the regional/national scale. We propose the implementation and use of thematic maps, such as the one built here, as a basic tool allowing public health authorities to focus surveillance efforts and normally scarce resources for prevention and control actions in vast areas like southern Argentina.

  15. Estimating Hantavirus Risk in Southern Argentina: A GIS-Based Approach Combining Human Cases and Host Distribution

    Directory of Open Access Journals (Sweden)

    Veronica Andreo

    2014-01-01

    Full Text Available We use a Species Distribution Modeling (SDM approach along with Geographic Information Systems (GIS techniques to examine the potential distribution of hantavirus pulmonary syndrome (HPS caused by Andes virus (ANDV in southern Argentina and, more precisely, define and estimate the area with the highest infection probability for humans, through the combination with the distribution map for the competent rodent host (Oligoryzomys longicaudatus. Sites with confirmed cases of HPS in the period 1995–2009 were mostly concentrated in a narrow strip (~90 km × 900 km along the Andes range from northern Neuquén to central Chubut province. This area is characterized by high mean annual precipitation (~1,000 mm on average, but dry summers (less than 100 mm, very low percentages of bare soil (~10% on average and low temperatures in the coldest month (minimum average temperature −1.5 °C, as compared to the HPS-free areas, features that coincide with sub-Antarctic forests and shrublands (especially those dominated by the invasive plant Rosa rubiginosa, where rodent host abundances and ANDV prevalences are known to be the highest. Through the combination of predictive distribution maps of the reservoir host and disease cases, we found that the area with the highest probability for HPS to occur overlaps only 28% with the most suitable habitat for O. longicaudatus. With this approach, we made a step forward in the understanding of the risk factors that need to be considered in the forecasting and mapping of risk at the regional/national scale. We propose the implementation and use of thematic maps, such as the one built here, as a basic tool allowing public health authorities to focus surveillance efforts and normally scarce resources for prevention and control actions in vast areas like southern Argentina.

  16. Evolution of cooperation in spatially structured populations

    Science.gov (United States)

    Brauchli; Killingback; Doebeli

    1999-10-21

    Using a spatial lattice model of the Iterated Prisoner's Dilemma we studied the evolution of cooperation within the strategy space of all stochastic strategies with a memory of one round. Comparing the spatial model with a randomly mixed model showed that (1) there is more cooperative behaviour in a spatially structured population, (2) PAVLOV and generous variants of it are very successful strategies in the spatial context and (3) in spatially structured populations evolution is much less chaotic than in unstructured populations. In spatially structured populations, generous variants of PAVLOV are found to be very successful strategies in playing the Iterated Prisoner's Dilemma. The main weakness of PAVLOV is that it is exploitable by defective strategies. In a spatial context this disadvantage is much less important than the good error correction of PAVLOV, and especially of generous PAVLOV, because in a spatially structured population successful strategies always build clusters. Copyright 1999 Academic Press.

  17. An intelligent geoportal for spatial planning

    CSIR Research Space (South Africa)

    Iwanaik, A

    2011-07-01

    Full Text Available The main idea of the INSPIRE directive, establishing an infrastructure for spatial information in Europe, is to remove barriers in using and sharing official spatial data by various groups of users (common, commercial, administrative) and avoid...

  18. Spatial analysis statistics, visualization, and computational methods

    CERN Document Server

    Oyana, Tonny J

    2015-01-01

    An introductory text for the next generation of geospatial analysts and data scientists, Spatial Analysis: Statistics, Visualization, and Computational Methods focuses on the fundamentals of spatial analysis using traditional, contemporary, and computational methods. Outlining both non-spatial and spatial statistical concepts, the authors present practical applications of geospatial data tools, techniques, and strategies in geographic studies. They offer a problem-based learning (PBL) approach to spatial analysis-containing hands-on problem-sets that can be worked out in MS Excel or ArcGIS-as well as detailed illustrations and numerous case studies. The book enables readers to: Identify types and characterize non-spatial and spatial data Demonstrate their competence to explore, visualize, summarize, analyze, optimize, and clearly present statistical data and results Construct testable hypotheses that require inferential statistical analysis Process spatial data, extract explanatory variables, conduct statisti...

  19. Integrating spatial statistics and remote sensing.

    NARCIS (Netherlands)

    Stein, A.; Bastiaanssen, W.G.M.; Bruin, de S.; Cracknell, A.P.; Curran, P.J.; Fabbri, A.G.; Gorte, B.G.H.; Groenigen, van J.W.; Meer, van der F.D.; Saldana, A.

    1998-01-01

    This paper presents an integrated approach towards spatial statistics for remote sensing. Using the layer concept in Geographical Information Systems we treat successively elements of spatial statistics, scale, classification, sampling and decision support. The layer concept allows to combine contin

  20. Spatial photon correlations in multiple scattering media

    DEFF Research Database (Denmark)

    Smolka, Stephan; Muskens, O.; Lagendijk, A.;

    2010-01-01

    We present the first angle-resolved measurements of spatial photon correlations that are induced by multiple scattering of light. The correlation relates multiple scattered photons at different spatial positions and depends on incident photon fluctuations.......We present the first angle-resolved measurements of spatial photon correlations that are induced by multiple scattering of light. The correlation relates multiple scattered photons at different spatial positions and depends on incident photon fluctuations....

  1. Residual analysis for spatial point processes

    DEFF Research Database (Denmark)

    Baddeley, A.; Turner, R.; Møller, Jesper

    We define residuals for point process models fitted to spatial point pattern data, and propose diagnostic plots based on these residuals. The techniques apply to any Gibbs point process model, which may exhibit spatial heterogeneity, interpoint interaction and dependence on spatial covariates. Ou...

  2. Spatial audio quality perception (part 1)

    DEFF Research Database (Denmark)

    Conetta, R.; Brookes, T.; Rumsey, F.

    2015-01-01

    Spatial audio processes (SAPs) commonly encountered in consumer audio reproduction systems are known to produce a range of impairments to spatial quality. By way of two listening tests, this paper investigated the degree of degradation of the spatial quality of six 5-channel audio recordings resu...

  3. Development of a Geometric Spatial Visualization Tool

    Science.gov (United States)

    Ganesh, Bibi; Wilhelm, Jennifer; Sherrod, Sonya

    2009-01-01

    This paper documents the development of the Geometric Spatial Assessment. We detail the development of this instrument which was designed to identify middle school students' strategies and advancement in understanding of four geometric concept domains (geometric spatial visualization, spatial projection, cardinal directions, and periodic patterns)…

  4. Future Teachers' Spatial Thinking Skills and Attitudes

    Science.gov (United States)

    Shin, Euikyung E.; Milson, Andrew J.; Smith, Thomas J.

    2016-01-01

    The spatial thinking skills and attitudes of geography majors were compared with those of future teachers majoring in elementary education and secondary social studies education. Scores were obtained for each group on two measures: the spatial skills test and the attitude toward spatial thinking inventory. Mean differences were examined based on…

  5. Spatial filters for focusing ultrasound images

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Gori, Paola

    2001-01-01

    . A new method for making spatial matched filter focusing of RF ultrasound data is proposed based on the spatial impulse response description of the imaging. The response from a scatterer at any given point in space relative to the transducer can be calculated, and this gives the spatial matched filter...

  6. Effect of GIS Learning on Spatial Thinking

    Science.gov (United States)

    Lee, Jongwon; Bednarz, Robert

    2009-01-01

    A spatial-skills test is used to examine the effect of GIS learning on the spatial thinking ability of college students. Eighty students at a large state university completed pre- and post- spatial-skills tests administered during the 2003 fall semester. Analysis of changes in the students' test scores revealed that GIS learning helped students…

  7. Exogenous spatial attention decreases audiovisual integration

    NARCIS (Netherlands)

    Van der Stoep, N.; Van der Stigchel, S.; Nijboer, T. C W

    2015-01-01

    Multisensory integration (MSI) and spatial attention are both mechanisms through which the processing of sensory information can be facilitated. Studies on the interaction between spatial attention and MSI have mainly focused on the interaction between endogenous spatial attention and MSI. Most of t

  8. How Do Children Describe Spatial Relationships?

    Science.gov (United States)

    Cox, M. V.; Richardson, J. Ryder

    1985-01-01

    Describes a study of children's production of locative prepositions in order to test H. Clark's hypotheses regarding the acquisition of spatial terms. Subjects were required to describe the spatial arrangement of two balls arranged in each of three spatial dimensions. (SED)

  9. Spatial audio quality perception (part 2)

    DEFF Research Database (Denmark)

    Conetta, R.; Brookes, T.; Rumsey, F.;

    2015-01-01

    location, envelopment, coverage angle, ensemble width, and spaciousness. They can also impact timbre, and changes to timbre can then influence spatial perception. Previously obtained data was used to build a regression model of perceived spatial audio quality in terms of spatial and timbral metrics...

  10. Spatial audio quality perception (part 2)

    DEFF Research Database (Denmark)

    Conetta, R.; Brookes, T.; Rumsey, F.

    2015-01-01

    location, envelopment, coverage angle, ensemble width, and spaciousness. They can also impact timbre, and changes to timbre can then influence spatial perception. Previously obtained data was used to build a regression model of perceived spatial audio quality in terms of spatial and timbral metrics...

  11. Development: Ages & Stages--Spatial Awareness

    Science.gov (United States)

    Poole, Carla; Miller, Susan A.; Church, Ellen Booth

    2006-01-01

    Spatial concepts such as a sense of distance are learned through movement and exploration which is the most effective way for children to gain body awareness and an understanding of spatial relationships. It simultaneously develops muscle strength, coordination, self-confidence, and thinking skills. Spatial awareness can be defined as "an…

  12. Spatial audio quality perception (part 1)

    DEFF Research Database (Denmark)

    Conetta, R.; Brookes, T.; Rumsey, F.;

    2015-01-01

    Spatial audio processes (SAPs) commonly encountered in consumer audio reproduction systems are known to produce a range of impairments to spatial quality. By way of two listening tests, this paper investigated the degree of degradation of the spatial quality of six 5-channel audio recordings resu...

  13. Mathematics, Spatial Ability and the Sexes.

    Science.gov (United States)

    Fennema, Elizabeth

    This report defines spatial ability operationally (consisting of three components) and reviews possible sex differences in this ability as reported in the literature. The relationship between mathematical ability and spatial ability is discussed. Researchable hypotheses about how differential spatial ability may effect mathematics achievement are…

  14. Decomposition of variance for spatial Cox processes

    DEFF Research Database (Denmark)

    Jalilian, Abdollah; Guan, Yongtao; Waagepetersen, Rasmus

    2013-01-01

    Spatial Cox point processes is a natural framework for quantifying the various sources of variation governing the spatial distribution of rain forest trees. We introduce a general criterion for variance decomposition for spatial Cox processes and apply it to specific Cox process models...

  15. Decomposition of variance for spatial Cox processes

    DEFF Research Database (Denmark)

    Jalilian, Abdollah; Guan, Yongtao; Waagepetersen, Rasmus

    Spatial Cox point processes is a natural framework for quantifying the various sources of variation governing the spatial distribution of rain forest trees. We introducea general criterion for variance decomposition for spatial Cox processes and apply it to specific Cox process models with additive...

  16. Decomposition of variance for spatial Cox processes

    DEFF Research Database (Denmark)

    Jalilian, Abdollah; Guan, Yongtao; Waagepetersen, Rasmus

    Spatial Cox point processes is a natural framework for quantifying the various sources of variation governing the spatial distribution of rain forest trees. We introduce a general criterion for variance decomposition for spatial Cox processes and apply it to specific Cox process models...

  17. Spatial coding-based approach for partitioning big spatial data in Hadoop

    Science.gov (United States)

    Yao, Xiaochuang; Mokbel, Mohamed F.; Alarabi, Louai; Eldawy, Ahmed; Yang, Jianyu; Yun, Wenju; Li, Lin; Ye, Sijing; Zhu, Dehai

    2017-09-01

    Spatial data partitioning (SDP) plays a powerful role in distributed storage and parallel computing for spatial data. However, due to skew distribution of spatial data and varying volume of spatial vector objects, it leads to a significant challenge to ensure both optimal performance of spatial operation and data balance in the cluster. To tackle this problem, we proposed a spatial coding-based approach for partitioning big spatial data in Hadoop. This approach, firstly, compressed the whole big spatial data based on spatial coding matrix to create a sensing information set (SIS), including spatial code, size, count and other information. SIS was then employed to build spatial partitioning matrix, which was used to spilt all spatial objects into different partitions in the cluster finally. Based on our approach, the neighbouring spatial objects can be partitioned into the same block. At the same time, it also can minimize the data skew in Hadoop distributed file system (HDFS). The presented approach with a case study in this paper is compared against random sampling based partitioning, with three measurement standards, namely, the spatial index quality, data skew in HDFS, and range query performance. The experimental results show that our method based on spatial coding technique can improve the query performance of big spatial data, as well as the data balance in HDFS. We implemented and deployed this approach in Hadoop, and it is also able to support efficiently any other distributed big spatial data systems.

  18. Spatial Coherence of Synchrotron Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Marchesini, S; Coisson, R

    2003-10-30

    Synchrotron Radiation (SR) has been widely used since the 80's as a tool for many applications of UV, soft X rays and hard X rays in condensed matter physics, chemistry and biology. The evolution of SR sources towards higher brightness has led to the design of low-emittance electron storage rings (emittance is the product of beam size and divergence), and the development of special source magnetic structures, as undulators. This means that more and more photons are available on a narrow bandwidth and on a small collimated beam; in other words there is the possibility of getting a high power in a coherent beam. In most applications, a monochromator is used, and the temporal coherence of the light is given by the monochromator bandwidth. With smaller and smaller sources, even without the use of collimators, the spatial coherence of the light has become appreciable, first in the UV and soft X ray range, and then also with hard X rays. This has made possible new or improved experiments in interferometry, microscopy, holography, correlation spectroscopy, etc. In view of these recent possibilities and applications, it is useful to review some basic concepts about spatial coherence of SR, and its measurement and applications. In particular we show how the spatial coherence properties of the radiation in the far field can be calculated with simple operations from the single-electron amplitude and the electron beam angular and position spreads. The gaussian approximation will be studied in detail for a discussion of the properties of the far field mutual coherence and the estimate of the coherence widths, and the comparison with the VanCittert-Zernike limit.

  19. Visual perception of spatial subjects

    Energy Technology Data Exchange (ETDEWEB)

    Osterloh, K.R.S.; Ewert, U. [Federal Institute for Materials Research and Testing (BAM), Berlin (Germany)

    2007-07-01

    Principally, any imaging technology consists of two consecutive, though strictly separated processes: data acquisition and subsequent processing to generate an image that can be looked at, either on a monitor screen or printed on paper. Likewise, the physiological process of viewing can be separated into vision and perception, though these processes are much more overlapping. Understanding the appearance of a subject requires the entire sequence from receiving the information carried e.g. by photons up to an appropriate processing leading to the perception of the subject shown. As a consequence, the imagination of a subject is a result of both, technological and physiological processes. Whenever an evaluation of an image is critical, also the physiological part of the processing should be considered. However, an image has two dimensions in the first place and reality is spatial, it has three dimensions. This problem has been tackled on a philosophical level at least since Platon's famous discussion on the shadow image in a dark cave. The mere practical point is which structural details can be perceived and what may remain undetected depending on the mode of presentation. This problem cannot be resolved without considering each single step of visual perception. Physiologically, there are three 'tools' available to understanding the spatial structure of a subject: binocular viewing, following the course of perspective projection and motion to collect multiple aspects. Artificially, an object may be cut in various ways to display the interior or covering parts could be made transparent within a model. Samples will be shown how certain details of a subject can be emphasised or hidden depending on the way of presentation. It needs to be discussed what might help to perceive the true spatial structure of a subject with all relevant details and what could be misleading. (authors)

  20. Spatial and Temporal Ray Differentials

    DEFF Research Database (Denmark)

    Sporring, Jon; Schjøth, Lars; Erleben, Kenny

    We consider ray bundles emanating from a source such as a camera or light source. We derive the full spatial and temporal structure to ¿rst order of the intersection of ray bundles with scene geometry, where scene geometry given as any implicit function. Further, we present the full details of 2...... often used geometrical representations. The ¿rst order structure may be used as the linear approximation of the change of photons as the camera, ob jects, and light source change as function of space and time. Our work generalises previous work on ray differentials [Igehy, 1999] and photon differentials...

  1. Spatial geometry and special relativity

    DEFF Research Database (Denmark)

    Kneubil, Fabiana Botelho

    2016-01-01

    In this work, it is shown the interplay of relative and absolute entities, which are present in both spatial geometry and special relativity. In order to strengthen the understanding of special relativity, we discuss firstly an instance of geometry and the existence of both frame......-dependent and frame-independent entities. We depart from a subject well known by students, which is the three-dimensional geometric space in order to compare, afterwards, with the treatment of four-dimensional space in the special relativity. The differences and similarities between these two subjects are also...

  2. Fundamentals of spatial data quality

    CERN Document Server

    Devillers, Rodolphe

    2010-01-01

    This book explains the concept of spatial data quality, a key theory for minimizing the risks of data misuse in a specific decision-making context. Drawing together chapters written by authors who are specialists in their particular field, it provides both the data producer and the data user perspectives on how to evaluate the quality of vector or raster data which are both produced and used. It also covers the key concepts in this field, such as: how to describe the quality of vector or raster data; how to enhance this quality; how to evaluate and document it, using methods such as metadata;

  3. Spatial heterodyne spectrometer for FLEX

    Science.gov (United States)

    Scott, Alan; Zheng, Sheng-Hai; Brown, Stephen; Bell, Andrew

    2007-10-01

    A spatial heterodyne spectrometer (SHS) has significant advantages for high spectral resolution imaging over narrow pre-selected bands compared to traditional solutions. Given comparable optical étendue at R~6500, a field-widened SHS will have a throughput-resolution product ~170 x larger than an air-spaced etalon spectrometer, and ~1000 x larger than a standard grating spectrometer. The monolithic glass Michelson design and lack of moving parts allows maximum stability of spectral calibration over the mission life. For these reasons, SHS offers considerable advantages for the core spectrometer instrument in the European Space Agency's (ESA) Fluorescence Explorer (FLEX) mission.

  4. Spatially confined assembly of nanoparticles.

    Science.gov (United States)

    Jiang, Lin; Chen, Xiaodong; Lu, Nan; Chi, Lifeng

    2014-10-21

    The ability to assemble NPs into ordered structures that are expected to yield collective physical or chemical properties has afforded new and exciting opportunities in the field of nanotechnology. Among the various configurations of nanoparticle assemblies, two-dimensional (2D) NP patterns and one-dimensional (1D) NP arrays on surfaces are regarded as the ideal assembly configurations for many technological devices, for example, solar cells, magnetic memory, switching devices, and sensing devices, due to their unique transport phenomena and the cooperative properties of NPs in assemblies. To realize the potential applications of NP assemblies, especially in nanodevice-related applications, certain key issues must still be resolved, for example, ordering and alignment, manipulating and positioning in nanodevices, and multicomponent or hierarchical structures of NP assemblies for device integration. Additionally, the assembly of NPs with high precision and high levels of integration and uniformity for devices with scaled-down dimensions has become a key and challenging issue. Two-dimensional NP patterns and 1D NP arrays are obtained using traditional lithography techniques (top-down strategies) or interfacial assembly techniques (bottom-up strategies). However, a formidable challenge that persists is the controllable assembly of NPs in desired locations over large areas with high precision and high levels of integration. The difficulty of this assembly is due to the low efficiency of small features over large areas in lithography techniques or the inevitable structural defects that occur during the assembly process. The combination of self-assembly strategies with existing nanofabrication techniques could potentially provide effective and distinctive solutions for fabricating NPs with precise position control and high resolution. Furthermore, the synergistic combination of spatially mediated interactions between nanoparticles and prestructures on surfaces may play

  5. The spatial glaciological data infrastructure

    Directory of Open Access Journals (Sweden)

    T. Y. Khromova

    2014-01-01

    Full Text Available Substantial and rapid environmental changes require developing methods which could be able to manage huge information flows, to optimize processes of the data acquisition, storage, analysis, and exchange. Such facilities can be provided by the newly developed GIS technologies. Digital data bases are used as the key component of the GIS methods. We present the system of glaciological data management, developed in the Institute of Geography of Russian Academy of Sciences (IGRAS. Digital Atlas «Snow and Ice on the Earth», glacier inventories and digital library are the basic structures making possible objective presentation of the glaciological knowledge and data. The system provides the data integration, access to the data base, and makes possible using the GIS techniques for analysis. Data integration technologies are designed to form the united information space of subject areas of the spatial data. The objects of integration in our study are the information resources of glaciology, accumulated in a distributed system of data on the IGRAS web servers and geoportals in forms of data and metadata bases, structured (in a particular format data files, object data files (plain text, documents, images, etc., and electronic atlases. The best option for formation of a large-scale distributed environment, integration of many information resources of glaciology is to provide the so-called interoperability of data. This refers to compliance with certain rules or usage of additional software tools that allows interaction between various spatial data. These are standards to which the integrated information resources of glaciology should satisfy. The result of integration of the glaciological data technology application is the series of software and technology solutions. The main result of this work is creation of geoportals «Electronic Earth» (www.webgeo.ru, «The Nature and Resources of the Russian North» (www.north.webgeo.ru, «IPY-IGRAS» (www

  6. Spatial confinement of muonium atoms

    Science.gov (United States)

    Khaw, K. S.; Antognini, A.; Prokscha, T.; Kirch, K.; Liszkay, L.; Salman, Z.; Crivelli, P.

    2016-08-01

    We report the achievement of spatial confinement of muonium atoms (the bound state of a positive muon and an electron). Muonium emitted into a vacuum from mesoporous silica reflects between two SiO2 confining surfaces separated by 1 mm. From the data, one can extract that the reflection probability on the confining surfaces kept at 100 K is about 90% and the reflection process is well described by a cosine law. This technique enables new experiments with this exotic atomic system and is a very important step towards a measurement of the 1 S -2 S transition frequency using continuous-wave laser spectroscopy.

  7. Spatial confinement of muonium atoms

    CERN Document Server

    Khaw, K S; Prokscha, T; Kirch, K; Liszkay, L; Salman, Z; Crivelli, P

    2016-01-01

    We report the achievement of spatial confinement of muonium atoms (the bound state of a positive muon and an electron). Muonium emitted into vacuum from mesoporous silica is forced to bounce back and forth between two SiO$_2$ confining surfaces separated by 1 mm. From the data, one can extract that the reflection on the confining surfaces is well described by a cosine law. This technique opens up a way to perform new experiments with this exotic atomic system and is a very important step towards a measurement of the 1S-2S transition frequency using continuous wave laser spectroscopy.

  8. Spatial coherence of random laser emission

    CERN Document Server

    Redding, Brandon; Cao, Hui

    2011-01-01

    We experimentally studied the spatial coherence of random laser emission from dye solutions containing nanoparticles. The spatial coherence, measured in a double-slit experiment, varied significantly with the density of scatterers and the size and shape of the excitation volume. A qualitative explanation is provided, illustrating the dramatic difference from the spatial coherence of a conventional laser. This work demonstrates that random lasers can be controlled to provide intense, spatially incoherent emission for applications in which spatial cross talk or speckle limit performance.

  9. Spatial analysis and planning under imprecision

    CERN Document Server

    Leung, Y

    1988-01-01

    The book deals with complexity, imprecision, human valuation, and uncertainty in spatial analysis and planning, providing a systematic exposure of a new philosophical and theoretical foundation for spatial analysis and planning under imprecision. Regional concepts and regionalization, spatial preference-utility-choice structures, spatial optimization with single and multiple objectives, dynamic spatial systems and their controls are analyzed in sequence.The analytical framework is based on fuzzy set theory. Basic concepts of fuzzy set theory are first discussed. Many numerical examples and emp

  10. Connecting mathematics learning through spatial reasoning

    Science.gov (United States)

    Mulligan, Joanne; Woolcott, Geoffrey; Mitchelmore, Michael; Davis, Brent

    2017-07-01

    Spatial reasoning, an emerging transdisciplinary area of interest to mathematics education research, is proving integral to all human learning. It is particularly critical to science, technology, engineering and mathematics (STEM) fields. This project will create an innovative knowledge framework based on spatial reasoning that identifies new pathways for mathematics learning, pedagogy and curriculum. Novel analytical tools will map the unknown complex systems linking spatial and mathematical concepts. It will involve the design, implementation and evaluation of a Spatial Reasoning Mathematics Program (SRMP) in Grades 3 to 5. Benefits will be seen through development of critical spatial skills for students, increased teacher capability and informed policy and curriculum across STEM education.

  11. The Syntax of Spatial Anaphora

    Directory of Open Access Journals (Sweden)

    Johan Rooryck

    2007-12-01

    Full Text Available In this paper, we provide a comprehensive Minimalist analysis of the apparent free variation between pronouns and anaphors in snake-sentences. Three sets of data provide the basis for the analysis: hitherto unobserved restrictions on quantifier-pronoun relationships, classical observations about the role of perspective or point of view (Cantrall 1974, and interpretive effects concerning the nature of the locative relationship (Kuno 1987. We propose an analysis of spatial prepositions in terms of Svenonius’ (2006 AxPartP. Spatial interpretations may be object-centered or observer-centered. We correlate these two interpretations with two distinct grammatical representations. The object-centered interpretation involves an Agree relation between AxPart and the complement of P, the observer-centered interpretation is the result of a binding relationship between AxPart and the Speaker, represented in MoodEvid P. An Agree relation requires the presence of the complex anaphor himself, whereas binding of AxPart by the Speaker is only compatible with the pronoun him.

  12. Spatial patterns of tidal heating

    CERN Document Server

    Beuthe, Mikael

    2012-01-01

    In a body periodically strained by tides, heating produced by viscous friction is far from homogeneous. I show here that the distribution of the dissipated power within a spherically stratified body is a linear combination of three angular functions. These angular functions depend only on the tidal potential whereas the radial weights are specified by the internal structure of the body. The 3D problem of predicting spatial patterns of dissipation at all radii is thus reduced to the 1D problem of computing weight functions. I compute spatial patterns in various toy models without assuming a specific rheology: a viscoelastic thin shell stratified in conductive and convective layers, an incompressible homogeneous body and a two-layer model of uniform density with a liquid or rigid core. For a body in synchronous rotation undergoing eccentricity tides, dissipation in a mantle surrounding a liquid core is highest at the poles. Within a softer layer (asthenosphere or icy layer), the same tides generate maximum heat...

  13. Spatial release from informational masking

    Science.gov (United States)

    Rakerd, Brad; Aaronson, Neil L.

    2001-05-01

    A new method for investigating spatial release from informational masking was developed and employed in two experiments. The new method is computer controlled and efficient. It employs the versatile coordinate response measure speech stimulus set [Bolia et al., J. Acoust. Soc. Am. 107, 1065 (2000)]. The experiments were conducted in an anechoic room, with a primary loudspeaker in front of the listener and a secondary loudspeaker at 60 deg to the right. Target messages were presented from the primary speaker only. For a standard, distractor messages, simultaneous with the target, were also presented from the primary speaker only. Spatial release was measured by presenting the distractors from both primary and secondary speakers with a temporal offset. Experiment 1 fixed the offset (secondary leading, +4 ms) and varied the number of distractors (1 to 3) and the target-to-distractor ratio (-12 to +4 dB). Masking release, sometimes as large as 10 dB, was found for all combinations of these variables. Experiment 2 varied the offset over a wide range of values. Substantial release from masking was found for both positive and negative offsets, but only in the range in which speech echoes are suppressed (<50 ms). [Work supported by NIDCD grant DC 00181.

  14. Omnidirectional Analysis of Spatial Manipulator

    Directory of Open Access Journals (Sweden)

    Yuquan Leng

    2015-01-01

    Full Text Available Space manipulators are mainly used in the spatial loading task. According to problems of the spatial loading diversity, the testing loading installing position, and the utilization ratio of a test platform, the space manipulator is asked to evaluate the position and attitude of itself. This paper proposes the Point Omnidirectional Coefficient (POC with unit attitude sphere/circle to describe attitude of the end-effector, which evaluates any points in the attainable space of the manipulators, in combination with the manipulation’s position message, and get relationships between its position and attitude of all points in the attainable space. It represents the mapping between sphere surface and plane for mission attitude constraints and the method for calculating volume of points space including attainable space, Omnidirectional space, and mission attitude space. Furthermore, the Manipulator Omnidirectional Coefficient based on mission or not is proposed for evaluating manipulator performance. Through analysis and simulation about 3D and 2D manipulators, the results show that the above theoretical approach is feasible and the relationships about link lengths, joints angles, attainable space, and Manipulator Omnidirectional Coefficient are drawn for guiding design.

  15. The Spatial Scaffold: The Effects of Spatial Context on Memory for Events

    Science.gov (United States)

    Robin, Jessica; Wynn, Jordana; Moscovitch, Morris

    2016-01-01

    Events always unfold in a spatial context, leading to the claim that it serves as a scaffold for encoding and retrieving episodic memories. The ubiquitous co-occurrence of spatial context with events may induce participants to generate a spatial context when hearing scenarios of events in which it is absent. Spatial context should also serve as an…

  16. Spatial information semantic query based on SPARQL

    Science.gov (United States)

    Xiao, Zhifeng; Huang, Lei; Zhai, Xiaofang

    2009-10-01

    How can the efficiency of spatial information inquiries be enhanced in today's fast-growing information age? We are rich in geospatial data but poor in up-to-date geospatial information and knowledge that are ready to be accessed by public users. This paper adopts an approach for querying spatial semantic by building an Web Ontology language(OWL) format ontology and introducing SPARQL Protocol and RDF Query Language(SPARQL) to search spatial semantic relations. It is important to establish spatial semantics that support for effective spatial reasoning for performing semantic query. Compared to earlier keyword-based and information retrieval techniques that rely on syntax, we use semantic approaches in our spatial queries system. Semantic approaches need to be developed by ontology, so we use OWL to describe spatial information extracted by the large-scale map of Wuhan. Spatial information expressed by ontology with formal semantics is available to machines for processing and to people for understanding. The approach is illustrated by introducing a case study for using SPARQL to query geo-spatial ontology instances of Wuhan. The paper shows that making use of SPARQL to search OWL ontology instances can ensure the result's accuracy and applicability. The result also indicates constructing a geo-spatial semantic query system has positive efforts on forming spatial query and retrieval.

  17. Life stages: interactions and spatial patterns.

    Science.gov (United States)

    Robertson, Suzanne L; Cushing, J M; Costantino, R F

    2012-02-01

    In many stage-structured species, different life stages often occupy separate spatial niches in a heterogeneous environment. Life stages of the giant flour beetle Tribolium brevicornis (Leconte), in particular adults and pupae, occupy different locations in a homogeneous habitat. This unique spatial pattern does not occur in the well-studied stored grain pests T. castaneum (Herbst) and T. confusum (Duval). We propose density dependent dispersal as a causal mechanism for this spatial pattern. We model and explore the spatial dynamics of T. brevicornis with a set of four density dependent integrodifference and difference equations. The spatial model exhibits multiple attractors: a spatially uniform attractor and a patchy attractor with pupae and adults spatially separated. The model attractors are consistent with experimental observations.

  18. Unimodal and crossmodal gradients of spatial attention

    DEFF Research Database (Denmark)

    Föcker, J.; Hötting, K.; Gondan, Matthias

    2010-01-01

    Behavioral and event-related potential (ERP) studies have shown that spatial attention is gradually distributed around the center of the attentional focus. The present study compared uni- and crossmodal gradients of spatial attention to investigate whether the orienting of auditory and visual...... spatial attention is based on modality specific or supramodal representations of space. Auditory and visual stimuli were presented from five speaker locations positioned in the right hemifield. Participants had to attend to the innermost or outmost right position in order to detect either visual...... or auditory deviant stimuli. Detection rates and event-related potentials (ERPs) indicated that spatial attention is distributed as a gradient. Unimodal spatial ERP gradients correlated with the spatial resolution of the modality. Crossmodal spatial gradients were always broader than the corresponding...

  19. The 3-D global spatial data model foundation of the spatial data infrastructure

    CERN Document Server

    Burkholder, Earl F

    2008-01-01

    Traditional methods for handling spatial data are encumbered by the assumption of separate origins for horizontal and vertical measurements. Modern measurement systems operate in a 3-D spatial environment. The 3-D Global Spatial Data Model: Foundation of the Spatial Data Infrastructure offers a new model for handling digital spatial data, the global spatial data model or GSDM. The GSDM preserves the integrity of three-dimensional spatial data while also providing additional benefits such as simpler equations, worldwide standardization, and the ability to track spatial data accuracy with greater specificity and convenience. This groundbreaking spatial model incorporates both a functional model and a stochastic model to connect the physical world to the ECEF rectangular system. Combining horizontal and vertical data into a single, three-dimensional database, this authoritative monograph provides a logical development of theoretical concepts and practical tools that can be used to handle spatial data mo...

  20. From Spatial Intelligence to Spatial Competences: The Results of Applied Geo-Research in Italian Schools

    OpenAIRE

    Emilia SARNO

    2012-01-01

    This contribution explains the connection between spatial intelligence and spatial competences and by indicating how the first is the cognitive matrix of abilities necessary to move in space as well as to represent it. Indeed, two are principal factors involved in the spatial intelligence: orientation and representation. Both are based on a close interaction between spatial thought and movement in space. I show the basic features of spatial intelligence through the analysis of specialist lit...

  1. Marine spatial planning in Cyprus

    Science.gov (United States)

    Hadjimitsis, Diofantos; Agapiou, Athos; Mettas, Christodoulos; Themistocleous, Kyriacos; Evagorou, Evagoras; Cuca, Branka; Papoutsa, Christiana; Nisantzi, Argyro; Mamouri, Rodanthi-Elisavet; Soulis, George; Xagoraris, Zafiris; Lysandrou, Vasiliki; Aliouris, Kyriacos; Ioannou, Nicolas; Pavlogeorgatos, Gerasimos

    2015-06-01

    Marine Spatial Planning (MSP), which is in concept similar to land-use planning, is a public process by which the relevant Member State's authorities analyse and organise human activities in marine areas to achieve ecological, economic and social objectives. MSP aims to promote sustainable growth of maritime economies, sustainable development of marine areas and sustainable use of marine resources. This paper highlights the importance of MSP and provides basic outcomes of the main European marine development. The already successful MSP plans can provide useful feedback and guidelines for other countries that are in the process of implementation of an integrated MSP, such as Cyprus. This paper presents part of the MSP project, of which 80% funded by the European Regional Development Fund (ERDF) and 20% from national contribution. An overview of the project is presented, including data acquisition, methodology and preliminary results for the implementation of MSP in Cyprus.

  2. Broadcast-Based Spatial Queries

    Institute of Scientific and Technical Information of China (English)

    Kwang-Jin Park; Moon-Bae Song; Chong-Sun Hwang

    2005-01-01

    Indexing techniques have been developed for wireless data broadcast environments, in order to conserve the scarce power resources of the mobile clients. However, the use of interleaved index segments in a broadcast cycle increases the average access latency for the clients. In this paper, the broadcast-based spatial query processing methods (BBS)are presented for the location-based services. In the BBS, broadcasted data objects are sorted sequentially based on their locations, and the server broadcasts the location dependent data along with an index segment. Then, a sequential prefetching and caching scheme is designed to reduce the query response time. The performance of this scheme is investigated in relation to various environmental variables, such as the distributions of the data objects, the average speed of the clients and the size of the service area.

  3. Spatially anisotropic Heisenberg kagome antiferromagnet

    Science.gov (United States)

    Apel, W.; Yavors'kii, T.; Everts, H.-U.

    2007-04-01

    In the search for spin-1/2 kagome antiferromagnets, the mineral volborthite has recently been the subject of experimental studies (Hiroi et al 2001 J. Phys. Soc. Japan 70 3377; Fukaya et al 2003 Phys. Rev. Lett. 91 207603; Bert et al 2004 J. Phys.: Condens. Matter 16 S829; Bert et al 2005 Phys. Rev. Lett. 95 087203). It has been suggested that the magnetic properties of this material are described by a spin-1/2 Heisenberg model on the kagome lattice with spatially anisotropic exchange couplings. We report on investigations of the {\\mathrm {Sp}}(\\mathcal {N}) symmetric generalization of this model in the large \\mathcal {N} limit. We obtain a detailed description of the dependence of possible ground states on the anisotropy and on the spin length S. A fairly rich phase diagram with a ferrimagnetic phase, incommensurate phases with and without long-range order and a decoupled chain phase emerges.

  4. Spatial light interference microscopy (SLIM).

    Science.gov (United States)

    Wang, Zhuo; Millet, Larry; Mir, Mustafa; Ding, Huafeng; Unarunotai, Sakulsuk; Rogers, John; Gillette, Martha U; Popescu, Gabriel

    2011-01-17

    We present spatial light interference microscopy (SLIM) as a new optical microscopy technique, capable of measuring nanoscale structures and dynamics in live cells via interferometry. SLIM combines two classic ideas in light imaging: Zernike's phase contrast microscopy, which renders high contrast intensity images of transparent specimens, and Gabor's holography, where the phase information from the object is recorded. Thus, SLIM reveals the intrinsic contrast of cell structures and, in addition, renders quantitative optical path-length maps across the sample. The resulting topographic accuracy is comparable to that of atomic force microscopy, while the acquisition speed is 1,000 times higher. We illustrate the novel insight into cell dynamics via SLIM by experiments on primary cell cultures from the rat brain. SLIM is implemented as an add-on module to an existing phase contrast microscope, which may prove instrumental in impacting the light microscopy field at a large scale.

  5. Natural Resources and Spatial Spillovers

    Science.gov (United States)

    Batbold, Dulguun

    Regions going through a natural resource boom tend to have higher average incomes and employment relative to the rest of the country. For policy analysis, a question that often needs to be answered is to what extent the economic growth in the extraction region spills over to neighboring areas. This thesis develops a detailed methodology for analyzing the economic effects of geographically localized shocks within the framework of a parsimonious spatial general equilibrium model, including various methods for estimating key parameters. This model-based approach is being offered as a complementary tool for applied researchers conducting economic impact analysis. Existing empirical methods such as input-output analysis or difference-in-difference estimation techniques are often not optimal for analyzing spatially correlated data, and this model-based methodology can be used to overcome their limitations. Another important advantage of this methodology is that it is computationally tractable and has a relatively low data requirement, which can make a particularly big difference in studying developing countries where data quality and availability can often be an insurmountable challenge. Following the exposition of the methodology, this thesis presents two separate applications, one involving a developed nation and the other a developing one. In the first case, the methodology is applied to analyze the economic impact of the shale energy boom that's been occurring in and around Bakken counties in western North Dakota and eastern Montana over the past decade. In the second case, the methodology is used to analyze the economic impact of the Oyu Tolgoi copper-gold mining project in the Southern Gobi region of Mongolia. A common conclusion that is drawn from the two applications mentioned above is that economic booms fueled by natural resource extracting industries are largely local and have limited spillover effects on neighboring regions.

  6. Maripa hantavirus in French Guiana: phylogenetic position and predicted spatial distribution of rodent hosts.

    Science.gov (United States)

    de Thoisy, Benoît; Matheus, Séverine; Catzeflis, François; Clément, Luc; Barrioz, Sébastien; Guidez, Amandine; Donato, Damien; Cornu, Jean-François; Brunaux, Olivier; Guitet, Stéphane; Lacoste, Vincent; Lavergne, Anne

    2014-06-01

    A molecular screening of wild-caught rodents was conducted in French Guiana, South America to identify hosts of the hantavirus Maripa described in 2008 in a hantavirus pulmonary syndrome (HPS) case. Over a 9-year period, 418 echimyids and murids were captured. Viral RNA was detected in two sigmodontine rodents, Oligoryzomys fulvescens and Zygodontomys brevicauda, trapped close to the house of a second HPS case that occurred in 2009 and an O. fulvescens close to the fourth HPS case identified in 2013. Sequences from the rodents had 96% and 97% nucleotide identity (fragment of S and M segments, respectively) with the sequence of the first human HPS case. Phylogenetic reconstructions based on the complete sequence of the S segment show that Maripa virus is closely related to Rio Mamore hantavirus. Using environmental descriptors of trapping sites, including vegetation, landscape units, rain, and human disturbance, a maximal entropy-based species distribution model allowed for identification of areas of higher predicted occurrence of the two rodents, where emergence risks of Maripa virus are expected to be higher.

  7. Environmentally Friendly Concept in Spatial Regulation

    Directory of Open Access Journals (Sweden)

    T Taryono

    2004-01-01

    Full Text Available Spatial order of a region include purpose of structure and interrelatedness of spatial order which as a unity of development mechanism. Spatial order can’t be part from law basic that is UUD’45 and GBHN, in order to the management can be integrated and keep the environment. Spatial order also take note of physical factor and non physical factor. Physical factor consist of soil, water, flora, and fauna. Non physical factors consist of environment, social, economic, and soon. The principle of arrangement of spatial order in a region include national region, regional and local, and a region as an administrative baoundary, that is local government authority, like province, district, subdistrict, and village. The effort for spatial ordering of the environment, for example ordering resource, arrangement of allocation and location, arrangement of environmental aesthetic  and arrangement of environmental quality.

  8. Integrated spatial sampling modeling of geospatial data

    Institute of Scientific and Technical Information of China (English)

    LI Lianfa; WANG Jinfeng

    2004-01-01

    Spatial sampling is a necessary and important method for extracting geospatial data and its methodology directly affects the geo-analysis results. Counter to the deficiency of separate models of spatial sampling, this article analyzes three crucial elements of spatial sampling (frame, correlation and decision diagram) and induces its general integrated model. The program of Spatial Sampling Integration (SSI) has been developed with Component Object Model (COM) to realize the general integrated model. In two practical applications, i.e. design of the monitoring network of natural disasters and sampling survey of the areas of non-cultivated land, SSI has produced accurate results at less cost, better realizing the cost-effective goal of sampling toward the geo-objects with spatial correlation. The two cases exemplify expanded application and convenient implementation of the general integrated model with inset components in an integrated environment, which can also be extended to other modeling of spatial analysis.

  9. Extraversion-introversion and spatial intelligence.

    Science.gov (United States)

    Dunn, A; Eliot, J

    1993-08-01

    The purpose of this study was to assess whether extraversion-introversion is related to spatial intelligence. First-year psychology students (58 men, 108 women) in an open-admission community college responded to a battery of black and white and color spatial ability tests, and the Eysenck Personality Inventory. As hypothesized, a small but significant relationship was found between scores on extraversion and on the SEK Test (colored spatial test). Gender differences in performance on the spatial tests favored males. Scores on three of the Spatial Dimensionality Tests correlated significantly with those on the SEK Test. Recommendations include investigating the effect of a variety of spatial problems in combination with other personality variables.

  10. Evaluating spatial patterns in hydrological modelling

    DEFF Research Database (Denmark)

    Koch, Julian

    of spatial information in a holistic assessment. Opposed, statistical measures typically only address a limited amount of spatial information. A web-based survey and a citizen science project are employed to quantify the collective perceptive skills of humans aiming at benchmarking spatial metrics...... of environmental science, such as meteorology, geostatistics or geography. In total, seven metrics are evaluated with respect to their capability to quantitatively compare spatial patterns. The human visual perception is often considered superior to computer based measures, because it integrates various dimensions...... with respect to their capability to mimic human evaluations. This PhD thesis aims at expanding the standard toolbox of spatial model evaluation with innovative metrics that adequately compare spatial patterns. Driven by the rise of more complex model structures and the increase of suitable remote sensing...

  11. KING GEORGE ISLAND SPATIAL DATA MODEL

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Distribution,interoperability,interactivity,component are four main features of distributed GIS.Based on the principle of hypermap,hypermedia and distributed database,the paper comes up with a kind of distributed spatial data model which is in accordance with those features of distributed GIS.The model takes catalog service as the outline of spatial information globalization,and defines data structure of hypermap node in different level.Based on the model,it is feasible to manage and process distributed spatial information,and integrate multi_source,heterogeneous spatial data into a framework.Traditionally,to retrieve and access spatial data via Internet is only by theme or map name.With the concept of the model,it is possible to retrieve,load,and link spatial data by vector_based graphics on the Internet.

  12. Ventral striatal plasticity and spatial memory.

    Science.gov (United States)

    Ferretti, Valentina; Roullet, Pascal; Sargolini, Francesca; Rinaldi, Arianna; Perri, Valentina; Del Fabbro, Martina; Costantini, Vivian J A; Annese, Valentina; Scesa, Gianluigi; De Stefano, Maria Egle; Oliverio, Alberto; Mele, Andrea

    2010-04-27

    Spatial memory formation is a dynamic process requiring a series of cellular and molecular steps, such as gene expression and protein translation, leading to morphological changes that have been envisaged as the structural bases for the engram. Despite the role suggested for medial temporal lobe plasticity in spatial memory, recent behavioral observations implicate specific components of the striatal complex in spatial information processing. However, the potential occurrence of neural plasticity within this structure after spatial learning has never been investigated. In this study we demonstrate that blockade of cAMP response element binding protein-induced transcription or inhibition of protein synthesis or extracellular proteolytic activity in the ventral striatum impairs long-term spatial memory. These findings demonstrate that, in the ventral striatum, similarly to what happens in the hippocampus, several key molecular events crucial for the expression of neural plasticity are required in the early stages of spatial memory formation.

  13. Residual analysis for spatial point processes

    DEFF Research Database (Denmark)

    Baddeley, A.; Turner, R.; Møller, Jesper

    We define residuals for point process models fitted to spatial point pattern data, and propose diagnostic plots based on these residuals. The techniques apply to any Gibbs point process model, which may exhibit spatial heterogeneity, interpoint interaction and dependence on spatial covariates. Our...... residuals generalise the well-known residuals for point processes in time, used in signal processing and survival analysis. An important difference is that the conditional intensity or hazard rate of the temporal point process must be replaced by the Papangelou conditional intensity $lambda$ of the spatial...... process. Residuals are ascribed to locations in the empty background, as well as to data points of the point pattern. We obtain variance formulae, and study standardised residuals. There is also an analogy between our spatial residuals and the usual residuals for (non-spatial) generalised linear models...

  14. Spatial heterodyne scanning laser confocal holographic microscopy

    CERN Document Server

    Liu, Changgeng

    2016-01-01

    Scanning laser confocal holographic microscopy using a spatial heterodyne detection method is presented. Spatial heterodyne detection technique employs a Mach-Zehnder interferometer with the reference beam frequency shifted by two acousto-optic modulators (AOM) relative to the object beam frequency. Different from the traditional temporal heterodyne detection technique in which hundreds temporal samples are taken at each scanning point to achieve the complex signal, the spatial heterodyne detection technique generates spatial interference fringes by use of a linear tempo-spatial relation provided by galvanometer scanning in a typical line-scanning confocal microscope or for the slow-scanning on one dimension in a point-scanning confocal microscope, thereby significantly reducing sampling rate and increasing the signal to noise ratio under the same illumination compared to the traditional temporal heterodyne counterpart. The proposed spatial heterodyne detection scheme applies to both line-scanning and point-s...

  15. Frozen spatial chaos induced by boundaries

    CERN Document Server

    Eguiluz, V M; Piro, O; Balle, S; Eguiluz, Victor M.; Hernandez-Garcia, Emilio; Piro, Oreste; Balle, Salvador

    1999-01-01

    We show that rather simple but non-trivial boundary conditions could induce the appearance of spatial chaos (that is stationary, stable, but spatially disordered configurations) in extended dynamical systems with very simple dynamics. We exemplify the phenomenon with a nonlinear reaction-diffusion equation in a two-dimensional undulated domain. Concepts from the theory of dynamical systems, and a transverse-single-mode approximation are used to describe the spatially chaotic structures.

  16. Ventral striatal plasticity and spatial memory

    OpenAIRE

    Ferretti, Valentina; Roullet, Pascal; Sargolini, Francesca; Rinaldi, Arianna; Perri, Valentina; Del Fabbro, Martina; Costantini, Vivian J. A.; ANNESE, VALENTINA; Scesa, Gianluigi; De Stefano, Maria Egle; Oliverio, Alberto; Mele, Andrea

    2010-01-01

    Spatial memory formation is a dynamic process requiring a series of cellular and molecular steps, such as gene expression and protein translation, leading to morphological changes that have been envisaged as the structural bases for the engram. Despite the role suggested for medial temporal lobe plasticity in spatial memory, recent behavioral observations implicate specific components of the striatal complex in spatial information processing. However, the potential occurrence of neural plasti...

  17. GEOPORTAL-A SPATIAL CLOUD INFORMATION SERVICE

    National Research Council Canada - National Science Library

    J.SRINIVAS; K.KANTI KUMAR; B.SANKARA BABU; Dr.N.SUBHASH CHANDRA; G.CHARLES BABU

    2011-01-01

    .... The cloud computing has advantages of good scalability, high reliability and high availability,which can provide powerful technical support to promote the capability of spatial information service...

  18. A neuromorphic model of spatial lookahead planning.

    Science.gov (United States)

    Ivey, Richard; Bullock, Daniel; Grossberg, Stephen

    2011-04-01

    In order to create spatial plans in a complex and changing world, organisms need to rapidly adapt to novel configurations of obstacles that impede simple routes to goal acquisition. Some animals can mentally create successful multistep spatial plans in new visuo-spatial layouts that preclude direct, one-segment routes to goal acquisition. Lookahead multistep plans can, moreover, be fully developed before an animal executes any step in the plan. What neural computations suffice to yield preparatory multistep lookahead plans during spatial cognition of an obstructed two-dimensional scene? To address this question, we introduce a novel neuromorphic system for spatial lookahead planning in which a feasible sequence of actions is prepared before movement begins. The proposed system combines neurobiologically plausible mechanisms of recurrent shunting competitive networks, visuo-spatial diffusion, and inhibition-of-return. These processes iteratively prepare a multistep trajectory to the desired goal state in the presence of obstacles. The planned trajectory can be stored using a primacy gradient in a sequential working memory and enacted by a competitive queuing process. The proposed planning system is compared with prior planning models. Simulation results demonstrate system robustness to environmental variations. Notably, the model copes with many configurations of obstacles that lead other visuo-spatial planning models into selecting undesirable or infeasible routes. Our proposal is inspired by mechanisms of spatial attention and planning in primates. Accordingly, our simulation results are compared with neurophysiological and behavioral findings from relevant studies of spatial lookahead behavior.

  19. Spatial Text Visualization Using Automatic Typographic Maps.

    Science.gov (United States)

    Afzal, S; Maciejewski, R; Jang, Yun; Elmqvist, N; Ebert, D S

    2012-12-01

    We present a method for automatically building typographic maps that merge text and spatial data into a visual representation where text alone forms the graphical features. We further show how to use this approach to visualize spatial data such as traffic density, crime rate, or demographic data. The technique accepts a vector representation of a geographic map and spatializes the textual labels in the space onto polylines and polygons based on user-defined visual attributes and constraints. Our sample implementation runs as a Web service, spatializing shape files from the OpenStreetMap project into typographic maps for any region.

  20. Spatial Disorientation Training – Demonstration and Avoidance

    NARCIS (Netherlands)

    Bles, W.

    2008-01-01

    Acclimatization ; Aerospace medicine ; Attitude indicators ; Aviation accidents ; Flight maneuvers ; Flight simulators ; Human factors engineering ; Orientation ; Perception ; Physiological effects ; Pilot training ; Pilots (personnel) ; Responses ; Reviews ; Situational awareness ; Spatial disorien

  1. Modelling evolution in a spatial continuum

    Science.gov (United States)

    Barton, N. H.; Etheridge, A. M.; Véber, A.

    2013-01-01

    We survey a class of models for spatially structured populations which we have called spatial Λ-Fleming-Viot processes. They arise from a flexible framework for modelling in which the key innovation is that random genetic drift is driven by a Poisson point process of spatial 'events'. We demonstrate how this overcomes some of the obstructions to modelling populations which evolve in two-(and higher-) dimensional spatial continua, how its predictions match phenomena observed in data and how it fits with classical models. Finally we outline some directions for future research.

  2. The alignment between spatial planning, transportation planning ...

    African Journals Online (AJOL)

    engagement processes, support, ... Carel Schoeman • The alignment between spatial planning, transportation planning and environmental ..... NDOT: Public Transport Strategy (2007) .... Community Land Reform Act 28 of 1996 (CLARA).

  3. NASA World Wind: Infrastructure for Spatial Data

    Science.gov (United States)

    Hogan, Patrick

    2011-01-01

    The world has great need for analysis of Earth observation data, be it climate change, carbon monitoring, disaster response, national defense or simply local resource management. To best provide for spatial and time-dependent information analysis, the world benefits from an open standards and open source infrastructure for spatial data. In the spirit of NASA's motto "for the benefit of all" NASA invites the world community to collaboratively advance this core technology. The World Wind infrastructure for spatial data both unites and challenges the world for innovative solutions analyzing spatial data while also allowing absolute command and control over any respective information exchange medium.

  4. Collaborative inhibition in spatial memory retrieval

    National Research Council Canada - National Science Library

    Sjolund, Lori A; Erdman, Matthew; Kelly, Jonathan W

    2014-01-01

    .... Two experiments were designed to explore whether collaborative inhibition, which has heretofore been studied using traditional memory stimuli such as word lists, also characterizes spatial memory retrieval...

  5. Children’s spatial thinking: Does talk about the spatial world matter?

    Science.gov (United States)

    Pruden, Shannon M.; Levine, Susan C.; Huttenlocher, Janellen

    2012-01-01

    In this paper we examine the relations between parent spatial language input, children’s own production of spatial language, and children’s later spatial abilities. Using a longitudinal study design, we coded the use of spatial language (i.e., words describing the spatial features and properties of objects; e.g., big, tall, circle, curvy, edge) from child age 14 to 46 months in a diverse sample of 52 parent-child dyads interacting in their home settings. These same children were given three non-verbal spatial tasks, items from a Spatial Transformation task (Levine et al., 1999), the Block Design subtest from the WPPSI-III (Wechsler, 2002), and items on the Spatial Analogies subtest from Primary Test of Cognitive Skills (Huttenlocher & Levine, 1990) at 54 months of age. We find that parents vary widely in the amount of spatial language they use with their children during everyday interactions. This variability in spatial language input, in turn, predicts the amount of spatial language children produce, controlling for overall parent language input. Furthermore, children who produce more spatial language are more likely to perform better on spatial problem solving tasks at a later age. PMID:22010900

  6. Spatial processing in color reproduction

    Science.gov (United States)

    Liu, Li; Yang, Yongyi; Stark, Henry

    2005-08-01

    We consider the reproduction of color subject to material and neighborhood constraints. By 'material constraints,' we mean any constraints that are applied to the amount of ink, lights, voltages, and currents that are used in the generation of color. In the first instance we consider the problem of reproducing a target color constrained by maximum additive color signals, such as in the phosphorescence process in a cathode ray tube. In the second instance we consider the more difficult problem of reproducing color subject to constraints on the maximum primary color variations in a (spatial) neighborhood. We introduce the idea of adjacent color variance (ACV) and then attempt to reproduce colors subject to an upper bound on the ACV. An algorithm that is suitable for this task is the method of vector space projections (VSP). In order to use VSP for constrained color reproduction, we use a novel approach to linearize nonlinear CIE-Lab space constraints. Experimental results are furnished that demonstrate that using the ACV as a bound helps to reduce reproduction artifacts in a color image.

  7. Path planning under spatial uncertainty.

    Science.gov (United States)

    Wiener, Jan M; Lafon, Matthieu; Berthoz, Alain

    2008-04-01

    In this article, we present experiments studying path planning under spatial uncertainties. In the main experiment, the participants' task was to navigate the shortest possible path to find an object hidden in one of four places and to bring it to the final destination. The probability of finding the object (probability matrix) was different for each of the four places and varied between conditions. Givensuch uncertainties about the object's location, planning a single path is not sufficient. Participants had to generate multiple consecutive plans (metaplans)--for example: If the object is found in A, proceed to the destination; if the object is not found, proceed to B; and so on. The optimal solution depends on the specific probability matrix. In each condition, participants learned a different probability matrix and were then asked to report the optimal metaplan. Results demonstrate effective integration of the probabilistic information about the object's location during planning. We present a hierarchical planning scheme that could account for participants' behavior, as well as for systematic errors and differences between conditions.

  8. Haptic perception of spatial relations.

    Science.gov (United States)

    Kappers, A M; Koenderink, J J

    1999-01-01

    There are some indications that haptic space like visual space is not Euclidean (e.g. Blumenfeld, 1937 Acta Psychologica 2 125-174). In a series of experiments, we investigated the haptic perception of spatial relations in a systematic way. We restricted ourselves to a horizontal plane at waist height. Blindfolded subjects were asked to perform three tasks with their right hand: (i) a reference bar was presented under four different orientations and subjects were asked to rotate a test bar such that it felt to be parallel to the reference bar; (ii) subjects had to rotate two test bars in such a way that they felt collinear; (iii) subjects had to point a test bar in the direction of a marker. Bars and marker could appear at nine different locations. In all experiments large systematic deviations (up to 40 degrees) were made. The deviations strongly correlated with horizontal (right-left) but not with vertical (forward-backward) distance. Subjects showed qualitatively identical trends but the size of the deviations was strongly subject-dependent. In addition, a significant haptic oblique effect was found. These results provide strong evidence that haptic space in non-Euclidean.

  9. Spatial Evolution of Human Dialects

    Science.gov (United States)

    Burridge, James

    2017-07-01

    The geographical pattern of human dialects is a result of history. Here, we formulate a simple spatial model of language change which shows that the final result of this historical evolution may, to some extent, be predictable. The model shows that the boundaries of language dialect regions are controlled by a length minimizing effect analogous to surface tension, mediated by variations in population density which can induce curvature, and by the shape of coastline or similar borders. The predictability of dialect regions arises because these effects will drive many complex, randomized early states toward one of a smaller number of stable final configurations. The model is able to reproduce observations and predictions of dialectologists. These include dialect continua, isogloss bundling, fanning, the wavelike spread of dialect features from cities, and the impact of human movement on the number of dialects that an area can support. The model also provides an analytical form for Séguy's curve giving the relationship between geographical and linguistic distance, and a generalization of the curve to account for the presence of a population center. A simple modification allows us to analytically characterize the variation of language use by age in an area undergoing linguistic change.

  10. Spatial search by quantum walk

    CERN Document Server

    Childs, A M; Childs, Andrew M.; Goldstone, Jeffrey

    2003-01-01

    Grover's quantum search algorithm provides a way to speed up combinatorial search, but is not directly applicable to searching a physical database. Nevertheless, Aaronson and Ambainis showed that a database of N items laid out in d spatial dimensions can be searched in time of order sqrt(N) for d>2, and in time of order sqrt(N) poly(log N) for d=2. We consider an alternative search algorithm based on a continuous time quantum walk on a graph. The case of the complete graph gives the continuous time search algorithm of Farhi and Gutmann, and other previously known results can be used to show that sqrt(N) speedup can also be achieved on the hypercube. We show that full sqrt(N) speedup can be achieved on a d-dimensional periodic lattice for d>4. In d=4, the quantum walk search algorithm takes time of order sqrt(N) poly(log N), and in d<4, the algorithm provides no speedup.

  11. Spatial scaling of the binocular capture effect.

    Science.gov (United States)

    Raghunandan, Avesh; Anderson, Coleman S; Saladin, James J

    2009-03-01

    Binocular "capture" occurs when the perceived visual direction of a monocular stimulus is displaced in the direction of the cyclopean visual direction of nearby binocular targets. This effect increases with the vertical separation of broadband monocular stimuli. The present study investigated whether the "capture" effect exhibits a systematic relationship with the spatial frequency composition of monocular lines and vertical separation. Subjects judged the horizontal misalignment of 66 arc min vertical spatial frequency ribbons that were temporally interleaved with a random dot depth edge (3.2 degrees) for 108 ms. Spatial frequency ribbons were constructed from horizontal cosine gratings windowed by a 4 arc min vertical Gaussian envelope. The bottom half of the depth edge was presented with zero relative disparity, whereas the top half was presented with 10 arc min of crossed or uncrossed relative disparity. Four vertical separations (8, 16, 30, and 60 arc min) and three ribbon spatial frequencies (1, 4, and 8 cpd) were tested. The horizontal ribbon offset corresponding to 50% performance was calculated for each combination of depth condition, ribbon spatial frequency, and vertical separation. The magnitude of the "capture" effect was consistently larger for higher spatial frequency ribbons and decreased with decreasing vertical separation. When vertical separation was expressed as multiples of spatial periods of the respective ribbon spatial frequency, the magnitude of effect was significantly larger for separations greater than about one spatial period. The systematic scaling of the "capture" effect with spatial frequency and vertical separation is strongly suggestive of the operation of multiple spatial scale mechanisms; similar to those advocated for the processing of relative positional acuity with increasing vertical separation of monocular targets.

  12. A spatially explicit risk approach to support marine spatial planning in the German EEZ.

    Science.gov (United States)

    Gimpel, Antje; Stelzenmüller, Vanessa; Cormier, Roland; Floeter, Jens; Temming, Axel

    2013-05-01

    An ecosystem approach to marine spatial planning (MSP) promotes sustainable development by organizing human activities in a geo-spatial and temporal context. (1) This study develops and tests a spatially explicit risk assessment to support MSP. Using the German exclusive economic zone (EEZ) of the North Sea as a case study area, current and future spatial management scenarios are assessed. (2) Different tools are linked in order to carry out a comprehensive spatial risk assessment of current and future spatial management scenarios for ecologic and economic ecosystem components, i.e. Pleuronectes platessa nursery grounds. With the identification of key inputs and outputs the suitability of each tool is tested. (3) Here, the procedure as well as the main findings of the spatially explicit risk approach are summarised to demonstrate the applicability of the framework and the need for an ecosystem approach to risk management techniques using geo-spatial tools.

  13. Version based spatial record management techniques for spatial database management system

    Institute of Scientific and Technical Information of China (English)

    KIM Ho-seok; KIM Hee-taek; KIM Myung-keun; BAE Hae-young

    2004-01-01

    The search operation of spatial data was a principal operation in existent spatial database management system, but the update operation of spatial data such as tracking are occurring frequently in the spatial database management system recently. So, necessity of concurrency improvement among transactions is increasing. In general database management system, many techniques have been studied to solve concurrency problem of transaction. Among them, multi-version algorithm does to minimize interference among transactions. However, to apply existent multi-version algorithm to improve concurrency of transaction to spatial database management system, the waste of storage happens because it must store entire version for spatial record even if only aspatial data of spatial record is changed. This paper has proposed the record management techniques to manage separating aspatial data version and spatial data version to decrease waste of storage for record version and improve concurrency among transactions.

  14. Plasticity of human spatial cognition: spatial language and cognition covary across cultures.

    Science.gov (United States)

    Haun, Daniel B M; Rapold, Christian J; Janzen, Gabriele; Levinson, Stephen C

    2011-04-01

    The present paper explores cross-cultural variation in spatial cognition by comparing spatial reconstruction tasks by Dutch and Namibian elementary school children. These two communities differ in the way they predominantly express spatial relations in language. Four experiments investigate cognitive strategy preferences across different levels of task-complexity and instruction. Data show a correlation between dominant linguistic spatial frames of reference and performance patterns in non-linguistic spatial memory tasks. This correlation is shown to be stable across an increase of complexity in the spatial array. When instructed to use their respective non-habitual cognitive strategy, participants were not easily able to switch between strategies and their attempts to do so impaired their performance. These results indicate a difference not only in preference but also in competence and suggest that spatial language and non-linguistic preferences and competences in spatial cognition are systematically aligned across human populations.

  15. Spatial Processing in Infancy Predicts Both Spatial and Mathematical Aptitude in Childhood.

    Science.gov (United States)

    Lauer, Jillian E; Lourenco, Stella F

    2016-10-01

    Despite considerable interest in the role of spatial intelligence in science, technology, engineering, and mathematics (STEM) achievement, little is known about the ontogenetic origins of individual differences in spatial aptitude or their relation to later accomplishments in STEM disciplines. The current study provides evidence that spatial processes present in infancy predict interindividual variation in both spatial and mathematical competence later in development. Using a longitudinal design, we found that children's performance on a brief visuospatial change-detection task administered between 6 and 13 months of age was related to their spatial aptitude (i.e., mental-transformation skill) and mastery of symbolic-math concepts at 4 years of age, even when we controlled for general cognitive abilities and spatial memory. These results suggest that nascent spatial processes present in the first year of life not only act as precursors to later spatial intelligence but also predict math achievement during childhood.

  16. Neurodynamics With Spatial Self-Organization

    Science.gov (United States)

    Zak, Michail A.

    1993-01-01

    Report presents theoretical study of dynamics of neural network organizing own response in both phase space and in position space. Postulates several mathematical models of dynamics including spatial derivatives representing local interconnections among neurons. Shows how neural responses propagate via these interconnections and how spatial pattern of neural responses formed in homogeneous biological neural network.

  17. Dynamic spatial panels : models, methods, and inferences

    NARCIS (Netherlands)

    Elhorst, J. Paul

    This paper provides a survey of the existing literature on the specification and estimation of dynamic spatial panel data models, a collection of models for spatial panels extended to include one or more of the following variables and/or error terms: a dependent variable lagged in time, a dependent

  18. Bone remodeling as a spatial evolutionary game.

    Science.gov (United States)

    Ryser, Marc D; Murgas, Kevin A

    2017-04-07

    Bone remodeling is a complex process involving cell-cell interactions, biochemical signaling and mechanical stimuli. Early models of the biological aspects of remodeling were non-spatial and focused on the local dynamics at a fixed location in the bone. Several spatial extensions of these models have been proposed, but they generally suffer from two limitations: first, they are not amenable to analysis and are computationally expensive, and second, they neglect the role played by bone-embedded osteocytes. To address these issues, we developed a novel model of spatial remodeling based on the principles of evolutionary game theory. The analytically tractable framework describes the spatial interactions between zones of bone resorption, bone formation and quiescent bone, and explicitly accounts for regulation of remodeling by bone-embedded, mechanotransducing osteocytes. Using tools from the theory of interacting particle systems we systematically classified the different dynamic regimes of the spatial model and identified regions of parameter space that allow for global coexistence of resorption, formation and quiescence, as observed in physiological remodeling. In coexistence scenarios, three-dimensional simulations revealed the emergence of sponge-like bone clusters. Comparison between spatial and non-spatial dynamics revealed substantial differences and suggested a stabilizing role of space. Our findings emphasize the importance of accounting for spatial structure and bone-embedded osteocytes when modeling the process of bone remodeling. Thanks to the lattice-based framework, the proposed model can easily be coupled to a mechanical model of bone loading.

  19. Spatial prioritisation for conserving ecosystem services

    NARCIS (Netherlands)

    Schröter, Matthias; Remme, Roy P.

    2015-01-01

    Context: The variation in spatial distribution between ecosystem services can be high. Hence, there is a need to spatially identify important sites for conservation planning. The term ‘ecosystem service hotspot’ has often been used for this purpose, but definitions of this term are ambiguous. Obj

  20. Chapter 12: spatial or area repellents

    Science.gov (United States)

    Spatial repellents a three-dimensional zone of protection around a host from attacks by biting arthropods. This chapter reviews current knowledge and outlines future directions for utilization of spatial repellents. Current knowledge includes the kinds of products, both active and passive devices,...

  1. Van der Waals forces and spatial dispersion

    OpenAIRE

    2009-01-01

    A version of the Green's functions theory of the Van der Waals forces which can be conveniently used in the presence of spatial dispersion is presented. The theory is based on the fluctuation-dissipation theorem and is valid for interacting bodies, separated by vacuum. Objections against theories acounting for the spatial dispersion are discussed.

  2. Spatial mode discrimination using second harmonic generation

    DEFF Research Database (Denmark)

    Delaubert, Vincent; Lassen, Mikael Østergaard; Pulford, David

    2007-01-01

    Second harmonic generation can be used as a technique for controlling the spatial mode structure of optical beams. We demonstrate experimentally the generation of higher order spatial modes, and that it is possible to use nonlinear phase matching as a predictable and robust technique for the conv...

  3. Two-wavelength spatial-heterodyne holography

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, Gregory R. (Clinton, TN); Bingham, Philip R. (Knoxville, TN); Simpson, John T. (Knoxville, TN); Karnowski, Thomas P. (Knoxville, TN); Voelkl, Edgar (Austin, TX)

    2007-12-25

    Systems and methods are described for obtaining two-wavelength differential-phase holograms. A method includes determining a difference between a filtered analyzed recorded first spatially heterodyne hologram phase and a filtered analyzed recorded second spatially-heterodyned hologram phase.

  4. The institutionalisation of European spatial planning

    NARCIS (Netherlands)

    Waterhout, B.

    2008-01-01

    This book questions whether and how European spatial planning is becoming institutionalised. Since the first steps towards creating spatial planning at the European level were taken some twenty years ago, it seems appropriate to look back at what has been achieved over this period. Notable achieveme

  5. Learning To Make Music Enhances Spatial Reasoning.

    Science.gov (United States)

    Hetland, Lois

    2000-01-01

    Examines whether active instruction in music enhances preschool and elementary school student performance on spatial tasks. Reports that music enhances the spatial-temporal performance of children during and up to two years following the instruction and that the effect is moderate and consistent. Includes references. (CMK)

  6. Spatial Language, Visual Attention, and Perceptual Simulation

    Science.gov (United States)

    Coventry, Kenny R.; Lynott, Dermot; Cangelosi, Angelo; Monrouxe, Lynn; Joyce, Dan; Richardson, Daniel C.

    2010-01-01

    Spatial language descriptions, such as "The bottle is over the glass", direct the attention of the hearer to particular aspects of the visual world. This paper asks how they do so, and what brain mechanisms underlie this process. In two experiments employing behavioural and eye tracking methodologies we examined the effects of spatial language on…

  7. Spatial Analysis Of Human Capital Structures

    Directory of Open Access Journals (Sweden)

    Gajdos Artur

    2014-12-01

    Full Text Available The main purpose of this paper is to analyse the interdependence between labour productivity and the occupational structure of human capital in a spatial cross-section. Research indicates (see Fischer 2009 the possibility to assess the impact of the quality of human capital (measured by means of the level of education on labour productivity in a spatial cross-section.

  8. Spatial coherence and entanglement of light

    NARCIS (Netherlands)

    Di Lorenzo Pires, Henrique

    2011-01-01

    In this thesis we investigate diverse aspects of spatial coherence of light. Non-classical fields containing two photons can be generated by a nonlinear optical process known as spontaneous parametric down conversion (SPDC). Among the questions we consider are: What is so special about spatial

  9. Spatial Ability Learning through Educational Robotics

    Science.gov (United States)

    Julià, Carme; Antolí, Juan Òscar

    2016-01-01

    Several authors insist on the importance of students' acquisition of spatial abilities and visualization in order to have academic success in areas such as science, technology or engineering. This paper proposes to discuss and analyse the use of educational robotics to develop spatial abilities in 12 year old students. First of all, a course to…

  10. Spatial abstraction for autonomous robot navigation.

    Science.gov (United States)

    Epstein, Susan L; Aroor, Anoop; Evanusa, Matthew; Sklar, Elizabeth I; Parsons, Simon

    2015-09-01

    Optimal navigation for a simulated robot relies on a detailed map and explicit path planning, an approach problematic for real-world robots that are subject to noise and error. This paper reports on autonomous robots that rely on local spatial perception, learning, and commonsense rationales instead. Despite realistic actuator error, learned spatial abstractions form a model that supports effective travel.

  11. Spatial Ability through Engineering Graphics Education

    Science.gov (United States)

    Marunic, Gordana; Glazar, Vladimir

    2013-01-01

    Spatial ability has been confirmed to be of particular importance for successful engineering graphics education and to be a component of human intelligence that can be improved through instruction and training. Consequently, the creation and communication by means of graphics demand careful development of spatial skills provided by the balanced…

  12. Voluntary attention increases perceived spatial frequency.

    Science.gov (United States)

    Abrams, Jared; Barbot, Antoine; Carrasco, Marisa

    2010-08-01

    Voluntary covert attention selects relevant sensory information for prioritized processing. The behavioral and neural consequences of such selection have been extensively documented, but its phenomenology has received little empirical investigation. Involuntary attention increases perceived spatial frequency (Gobell & Carrasco, 2005), but involuntary attention can differ from voluntary attention in its effects on performance in tasks mediated by spatial resolution (Yeshurun, Montagna, & Carrasco, 2008). Therefore, we ask whether voluntary attention affects the subjective appearance of spatial frequency--a fundamental dimension of visual perception underlying spatial resolution. We used a demanding rapid serial visual presentation task to direct voluntary attention and measured perceived spatial frequency at the attended and unattended locations. Attention increased the perceived spatial frequency of suprathreshold stimuli and also improved performance on a concurrent orientation discrimination task. In the control experiment, we ruled out response bias as an alternative account by using a lengthened interstimulus interval, which allows observers to disengage attention from the cued location. In contrast to the main experiment, the observers showed neither increased perceived spatial frequency nor improved orientation discrimination at the attended location. Thus, this study establishes that voluntary attention increases perceived spatial frequency. This phenomenological consequence links behavioral and neurophysiological studies on the effects of attention.

  13. West African spatial patterns of economic activities

    DEFF Research Database (Denmark)

    Walther, Olivier; Howard, Allen; Retaillé, Denis

    2015-01-01

    Over the last 30 years, two different bodies of literature developed by both US historians and francophone geographers have moved toward similar conclusions regarding West African economic spatial patterns. Despite their different backgrounds, both the ‘spatial factor’ approach promoted...

  14. Spatial Econometrics: A Rapidly Evolving Discipline

    Directory of Open Access Journals (Sweden)

    Giuseppe Arbia

    2016-03-01

    Full Text Available Spatial econometrics has a relatively short history in the scenario of the scientific thought. Indeed, the term “spatial econometrics” was introduced only forty years ago during the general address delivered by Jean Paelinck to the annual meeting of the Dutch Statistical Association in May 1974 (see [1]. [...

  15. The Spatial Know-How of Graffiti

    Directory of Open Access Journals (Sweden)

    Jannes van Loon

    2015-06-01

    Full Text Available My research interest lies in understand the spatial behaviour of graffiti writers (van Loon, 2014. Although graffiti writers have unique perspectives on urban landscapes that determine where and what type of graffiti they produce, they also have collective or shared senses of place – i.e., a spatial know-how that structures their production (Castree, 2003.

  16. The Spatial Know-How of Graffiti

    Directory of Open Access Journals (Sweden)

    Jannes van Loon

    2016-03-01

    Full Text Available My research interest lies in understand the spatial behaviour of graffiti writers (van Loon, 2014. Although graffiti writers have unique perspectives on urban landscapes that determine where and what type of graffiti they produce, they also have collective or shared senses of place – i.e., a spatial know-how that structures their production (Castree, 2003.

  17. Improving Student Understanding of Spatial Ecology Statistics

    Science.gov (United States)

    Hopkins, Robert, II; Alberts, Halley

    2015-01-01

    This activity is designed as a primer to teaching population dispersion analysis. The aim is to help improve students' spatial thinking and their understanding of how spatial statistic equations work. Students use simulated data to develop their own statistic and apply that equation to experimental behavioral data for Gambusia affinis (western…

  18. Unit 127 - Spatial Decision Support Systems

    OpenAIRE

    064, CC in GIScience; Malczewski, Jacek; Keller, C Peter

    2000-01-01

    This unit focuses on the concept of Spatial Decision Support Systems (SDSS). It covers the major characteristics of spatial decision problems; the decision-making process; a definition of SDSS; principles of SDSS; the dialog, data, model (DDM) paradigm; and technologies for developing SDSS.

  19. Continuous-Time Modeling with Spatial Dependence

    NARCIS (Netherlands)

    Oud, J.H.L.; Folmer, H.; Patuelli, R.; Nijkamp, P.

    2012-01-01

    (Spatial) panel data are routinely modeled in discrete time (DT). However, compelling arguments exist for continuous-time (CT) modeling of (spatial) panel data. Particularly, most social processes evolve in CT, so that statistical analysis in DT is an oversimplification, gives an incomplete

  20. Continuous-Time Modeling with Spatial Dependence

    NARCIS (Netherlands)

    Oud, J.; Folmer, H.; Patuelli, R.; Nijkamp, P.

    (Spatial) panel data are routinely modeled in discrete time (DT). However, compelling arguments exist for continuous-time (CT) modeling of (spatial) panel data. Particularly, most social processes evolve in CT, so that statistical analysis in DT is an oversimplification, gives an incomplete

  1. Neurodynamics With Spatial Self-Organization

    Science.gov (United States)

    Zak, Michail A.

    1993-01-01

    Report presents theoretical study of dynamics of neural network organizing own response in both phase space and in position space. Postulates several mathematical models of dynamics including spatial derivatives representing local interconnections among neurons. Shows how neural responses propagate via these interconnections and how spatial pattern of neural responses formed in homogeneous biological neural network.

  2. Disturbances of spatial perception in children.

    Science.gov (United States)

    Meerwaldt, J D; van Dongen, H R

    1988-12-01

    Spatial perception was tested in 12 children with a localized brain lesion by means of the rod orientation test, line orientation test and facial recognition test. Only children with a lesion of the right hemisphere showed a disturbance of spatial perception.

  3. Improving Student Understanding of Spatial Ecology Statistics

    Science.gov (United States)

    Hopkins, Robert, II; Alberts, Halley

    2015-01-01

    This activity is designed as a primer to teaching population dispersion analysis. The aim is to help improve students' spatial thinking and their understanding of how spatial statistic equations work. Students use simulated data to develop their own statistic and apply that equation to experimental behavioral data for Gambusia affinis (western…

  4. Spatial information processing in humans and monkeys

    NARCIS (Netherlands)

    Oleksiak, A.

    2010-01-01

    In this thesis a series of experiments are described on human volunteers and rhesus monkeys (Macaca mulatta) in the context of spatial information processing. In the first single-unit recording experiments in monkeys a spatial summation algorithm was investigated. The responses of single neurons to

  5. Spatial and Social Networks in Organizational Innovation

    Science.gov (United States)

    Wineman, Jean D.; Kabo, Felichism W.; Davis, Gerald F.

    2009-01-01

    Research on the enabling factors of innovation has focused on either the social component of organizations or on the spatial dimensions involved in the innovation process. But no one has examined the aggregate consequences of the link from spatial layout, to social networks, to innovation. This project enriches our understanding of how innovation…

  6. Spatial mode discrimination using second harmonic generation

    DEFF Research Database (Denmark)

    Delaubert, Vincent; Lassen, Mikael Østergaard; Pulford, David

    2007-01-01

    Second harmonic generation can be used as a technique for controlling the spatial mode structure of optical beams. We demonstrate experimentally the generation of higher order spatial modes, and that it is possible to use nonlinear phase matching as a predictable and robust technique for the conv...

  7. Mobile Spatial Tools for Fluid Interaction

    NARCIS (Netherlands)

    Isenberg, Tobias; Nix, Simon; Schwarz, Martin; Miede, André; Scott, Stacey D.; Carpendale, Sheelagh

    2007-01-01

    Fluid interaction techniques are increasingly important for effective work on interactive displays such as tabletops. We introduce mobile spatial tools to support such fluid interaction by affecting the properties of objects in the interface spatially rather than temporally. Our tools allow us to co

  8. Why Do Spatial Abilities Predict Mathematical Performance?

    Science.gov (United States)

    Tosto, Maria Grazia; Hanscombe, Ken B.; Haworth, Claire M. A.; Davis, Oliver S. P.; Petrill, Stephen A.; Dale, Philip S.; Malykh, Sergey; Plomin, Robert; Kovas, Yulia

    2014-01-01

    Spatial ability predicts performance in mathematics and eventual expertise in science, technology and engineering. Spatial skills have also been shown to rely on neuronal networks partially shared with mathematics. Understanding the nature of this association can inform educational practices and intervention for mathematical underperformance.…

  9. The Spatial Behaviour of Animals and Men

    Science.gov (United States)

    Brindley, T. S.

    1973-01-01

    Describes some common patterns of animal spatial behavior, and discusses spatial relationships that can be observed as an important component of human social behavior. Reports the results of a study relating to the interpersonal distances of people in bus queues in Britain. (JR)

  10. Developing Spatial Orientation and Spatial Memory with a Treasure Hunting Game

    Science.gov (United States)

    Lin, Chien-Heng; Chen, Chien-Min; Lou, Yu-Chiung

    2014-01-01

    The abilities of both spatial orientation and spatial memory play very important roles in human navigation and spatial cognition. Since such abilities are difficult to strengthen through books or classroom instruction, there are no particular curricula or methods to assist in their development. Therefore, this study develops a spatial…

  11. Spatial Working Memory Interferes with Explicit, but Not Probabilistic Cuing of Spatial Attention

    Science.gov (United States)

    Won, Bo-Yeong; Jiang, Yuhong V.

    2015-01-01

    Recent empirical and theoretical work has depicted a close relationship between visual attention and visual working memory. For example, rehearsal in spatial working memory depends on spatial attention, whereas adding a secondary spatial working memory task impairs attentional deployment in visual search. These findings have led to the proposal…

  12. Spatial Working Memory Interferes with Explicit, but Not Probabilistic Cuing of Spatial Attention

    Science.gov (United States)

    Won, Bo-Yeong; Jiang, Yuhong V.

    2015-01-01

    Recent empirical and theoretical work has depicted a close relationship between visual attention and visual working memory. For example, rehearsal in spatial working memory depends on spatial attention, whereas adding a secondary spatial working memory task impairs attentional deployment in visual search. These findings have led to the proposal…

  13. Spatially varying coefficient models in real estate: Eigenvector spatial filtering and alternative approaches

    NARCIS (Netherlands)

    Helbich, M; Griffith, D

    2016-01-01

    Real estate policies in urban areas require the recognition of spatial heterogeneity in housing prices to account for local settings. In response to the growing number of spatially varying coefficient models in housing applications, this study evaluated four models in terms of their spatial patterns

  14. Multiscale Bone Remodelling with Spatial P Systems

    CERN Document Server

    Cacciagrano, Diletta; Merelli, Emanuela; Tesei, Luca; 10.4204/EPTCS.40.6

    2010-01-01

    Many biological phenomena are inherently multiscale, i.e. they are characterized by interactions involving different spatial and temporal scales simultaneously. Though several approaches have been proposed to provide "multilayer" models, only Complex Automata, derived from Cellular Automata, naturally embed spatial information and realize multiscaling with well-established inter-scale integration schemas. Spatial P systems, a variant of P systems in which a more geometric concept of space has been added, have several characteristics in common with Cellular Automata. We propose such a formalism as a basis to rephrase the Complex Automata multiscaling approach and, in this perspective, provide a 2-scale Spatial P system describing bone remodelling. The proposed model not only results to be highly faithful and expressive in a multiscale scenario, but also highlights the need of a deep and formal expressiveness study involving Complex Automata, Spatial P systems and other promising multiscale approaches, such as ...

  15. The Neoliberalisation of Strategic Spatial Planning

    DEFF Research Database (Denmark)

    Olesen, Kristian

    Despite the fact that strategic spatial planning practices recently have taken ‘a neoliberal turn’ in many European countries, ‘neoliberalism’ and ‘neoliberalisation’ are rarely used as analytical concepts in planning theory. This paper seeks to fill in part of this gap by examining...... the relationship between neoliberalism and strategic spatial planning. This is done through an analysis how the key theoretical ideas underpinning strategic spatial planning might be appropriated by neoliberal political agendas in planning practice. In conclusion, the paper argues that neoliberalism...... and neoliberalisation are helpful analytical concepts to examine and understand contemporary transformations of spatial planning discourses and practices, and that planning theory by adopting such analytical concepts can play an important role in assisting critical empirical studies of how spatial planning practices...

  16. The reorientation of spatial planning in Denmark

    DEFF Research Database (Denmark)

    Galland, Daniel

    2011-01-01

    has been reoriented at national, regional and urban/local levels over time. The fundamental objective of the project is hence to explore and examine the history and evolution of Danish spatial planning through three embedded case studies from inception until most recent transformations. Respectively......, these studies embrace the reorientations of Danish national spatial planning; regional spatial planning in North Jutland; and urban planning and waterfront redevelopment in the city of Aalborg. In attaining its aim, the dissertation is guided by the general premise that the reorientations of spatial planning...... planning practices at different administrative levels. As a whole, the outcome of this dissertation confirms that there is an increasing policy and institutional mismatch between national, regional and urban/local planning practices. It further suggests that the lack of spatial reflexion embedded...

  17. Presence and the utility of audio spatialization

    DEFF Research Database (Denmark)

    Bormann, Karsten

    2005-01-01

    performance by varying the spatial fidelity of the audio independently of its relevance to performance on the search task that subjects were to perform. This was achieved by having conditions in which subjects searched for a music-playing radio (an active sound source) and having conditions in which......The primary concern of this paper is whether the utility of audio spatialization, as opposed to the fidelity of audio spatialization, impacts presence. An experiment is reported that investigates the presence-performance relationship by decoupling spatial audio fidelity (realism) from task...... the playing radio would be stationary (a passive sound source) while subjects searched for some other object. Independent of this, the music emitted by the radio would be either fully spatialized or directional but nonattenuated. Findings include that for subjects searching for the active sound source, being...

  18. Bayesian Spatial Modelling with R-INLA

    Directory of Open Access Journals (Sweden)

    Finn Lindgren

    2015-02-01

    Full Text Available The principles behind the interface to continuous domain spatial models in the R- INLA software package for R are described. The integrated nested Laplace approximation (INLA approach proposed by Rue, Martino, and Chopin (2009 is a computationally effective alternative to MCMC for Bayesian inference. INLA is designed for latent Gaussian models, a very wide and flexible class of models ranging from (generalized linear mixed to spatial and spatio-temporal models. Combined with the stochastic partial differential equation approach (SPDE, Lindgren, Rue, and Lindstrm 2011, one can accommodate all kinds of geographically referenced data, including areal and geostatistical ones, as well as spatial point process data. The implementation interface covers stationary spatial mod- els, non-stationary spatial models, and also spatio-temporal models, and is applicable in epidemiology, ecology, environmental risk assessment, as well as general geostatistics.

  19. Telerobotic Pointing Gestures Shape Human Spatial Cognition

    CERN Document Server

    Cabibihan, John-John; Saj, Sujin; Zhang, Zhengchen

    2012-01-01

    This paper aimed to explore whether human beings can understand gestures produced by telepresence robots. If it were the case, they can derive meaning conveyed in telerobotic gestures when processing spatial information. We conducted two experiments over Skype in the present study. Participants were presented with a robotic interface that had arms, which were teleoperated by an experimenter. The robot could point to virtual locations that represented certain entities. In Experiment 1, the experimenter described spatial locations of fictitious objects sequentially in two conditions: speech condition (SO, verbal descriptions clearly indicated the spatial layout) and speech and gesture condition (SR, verbal descriptions were ambiguous but accompanied by robotic pointing gestures). Participants were then asked to recall the objects' spatial locations. We found that the number of spatial locations recalled in the SR condition was on par with that in the SO condition, suggesting that telerobotic pointing gestures c...

  20. Spatially dependent Kondo effect in Quantum Corrals

    Science.gov (United States)

    Rossi, Enrico; Morr, Dirk K.

    2007-03-01

    We study the Kondo screening of a single magnetic impurity placed inside a quantum corral consisting of non-magnetic impurities on the surface of a metallic host system. We show that the spatial structure of the corral's eigenmodes leads to a spatially dependent Kondo effect whose signatures are experimentally measurable spatial variations of the Kondo temperature, TK, and of the critical Kondo coupling, Jcr. Moreover we find that the screening of the magnetic impurity is accompanied by the formation of multiple Kondo resonances with characteristic spatial patterns that provide further experimental signatures of the spatially dependent Kondo effect. Our results demonstrate that quantum corrals provide new possibilities to manipulate and explore the Kondo effect.

  1. Spatial distributions of niche-constructing populations

    Directory of Open Access Journals (Sweden)

    Xiaozhuo Han

    2015-12-01

    Full Text Available Niche construction theory regards organisms not only as the object of natural selection but also an active subject that can change their own selective pressure through eco-evolutionary feedbacks. Through reviewing the existing works on the theoretical models of niche construction, here we present the progress made on how niche construction influences genetic structure of spatially structured populations and the spatial-temporal dynamics of metapopulations, with special focuses on mathematical models and simulation methods. The majority of results confirmed that niche construction can significantly alter the evolutionary trajectories of structured populations. Organism-environmental interactions induced by niche construction can have profound influence on the dynamics, competition and diversity of metapopulations. It can affect fine-scale spatially distribution of species and spatial heterogeneity of the environment. We further propose a few research directions with potentials, such as applying adaptive dynamics or spatial game theory to explore the effect of niche construction on phenotypic evolution and diversification.

  2. Spatial normalization of array-CGH data

    Directory of Open Access Journals (Sweden)

    Brennetot Caroline

    2006-05-01

    Full Text Available Abstract Background Array-based comparative genomic hybridization (array-CGH is a recently developed technique for analyzing changes in DNA copy number. As in all microarray analyses, normalization is required to correct for experimental artifacts while preserving the true biological signal. We investigated various sources of systematic variation in array-CGH data and identified two distinct types of spatial effect of no biological relevance as the predominant experimental artifacts: continuous spatial gradients and local spatial bias. Local spatial bias affects a large proportion of arrays, and has not previously been considered in array-CGH experiments. Results We show that existing normalization techniques do not correct these spatial effects properly. We therefore developed an automatic method for the spatial normalization of array-CGH data. This method makes it possible to delineate and to eliminate and/or correct areas affected by spatial bias. It is based on the combination of a spatial segmentation algorithm called NEM (Neighborhood Expectation Maximization and spatial trend estimation. We defined quality criteria for array-CGH data, demonstrating significant improvements in data quality with our method for three data sets coming from two different platforms (198, 175 and 26 BAC-arrays. Conclusion We have designed an automatic algorithm for the spatial normalization of BAC CGH-array data, preventing the misinterpretation of experimental artifacts as biologically relevant outliers in the genomic profile. This algorithm is implemented in the R package MANOR (Micro-Array NORmalization, which is described at http://bioinfo.curie.fr/projects/manor and available from the Bioconductor site http://www.bioconductor.org. It can also be tested on the CAPweb bioinformatics platform at http://bioinfo.curie.fr/CAPweb.

  3. Borrelia chilensis, a new member of the Borrelia burgdorferi sensu lato complex that extends the range of this genospecies in the Southern Hemisphere.

    Science.gov (United States)

    Ivanova, Larisa B; Tomova, Alexandra; González-Acuña, Daniel; Murúa, Roberto; Moreno, Claudia X; Hernández, Claudio; Cabello, Javier; Cabello, Carlos; Daniels, Thomas J; Godfrey, Henry P; Cabello, Felipe C

    2014-04-01

    Borrelia burgdorferi sensu lato (s.l.), transmitted by Ixodes spp. ticks, is the causative agent of Lyme disease. Although Ixodes spp. ticks are distributed in both Northern and Southern Hemispheres, evidence for the presence of B. burgdorferi s.l. in South America apart from Uruguay is lacking. We now report the presence of culturable spirochetes with flat-wave morphology and borrelial DNA in endemic Ixodes stilesi ticks collected in Chile from environmental vegetation and long-tailed rice rats (Oligoryzomys longicaudatus). Cultured spirochetes and borrelial DNA in ticks were characterized by multilocus sequence typing and by sequencing five other loci (16S and 23S ribosomal genes, 5S-23S intergenic spacer, flaB, ospC). Phylogenetic analysis placed this spirochete as a new genospecies within the Lyme borreliosis group. Its plasmid profile determined by polymerase chain reaction and pulsed-field gel electrophoresis differed from that of B. burgdorferi B31A3. We propose naming this new South American member of the Lyme borreliosis group B. chilensis VA1 in honor of its country of origin. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.

  4. Measurement of turbulent spatial structure and kinetic energy spectrum by exact temporal-to-spatial mapping

    DEFF Research Database (Denmark)

    Buchhave, Preben; Velte, Clara Marika

    2017-01-01

    and spatial structure functions in a way that completely bypasses the need for Taylor’s hypothesis. The spatial statistics agree with the classical counterparts, such as the total kinetic energy spectrum, at least for spatial extents up to the Taylor microscale. The requirements for applying the method......We present a method for converting a time record of turbulent velocity measured at a point in a flow to a spatial velocity record consisting of consecutive convection elements. The spatial record allows computation of dynamic statistical moments such as turbulent kinetic wavenumber spectra...

  5. Spectral-spatial hyperspectral image classification using super-pixel-based spatial pyramid representation

    Science.gov (United States)

    Fan, Jiayuan; Tan, Hui Li; Toomik, Maria; Lu, Shijian

    2016-10-01

    Spatial pyramid matching has demonstrated its power for image recognition task by pooling features from spatially increasingly fine sub-regions. Motivated by the concept of feature pooling at multiple pyramid levels, we propose a novel spectral-spatial hyperspectral image classification approach using superpixel-based spatial pyramid representation. This technique first generates multiple superpixel maps by decreasing the superpixel number gradually along with the increased spatial regions for labelled samples. By using every superpixel map, sparse representation of pixels within every spatial region is then computed through local max pooling. Finally, features learned from training samples are aggregated and trained by a support vector machine (SVM) classifier. The proposed spectral-spatial hyperspectral image classification technique has been evaluated on two public hyperspectral datasets, including the Indian Pines image containing 16 different agricultural scene categories with a 20m resolution acquired by AVIRIS and the University of Pavia image containing 9 land-use categories with a 1.3m spatial resolution acquired by the ROSIS-03 sensor. Experimental results show significantly improved performance compared with the state-of-the-art works. The major contributions of this proposed technique include (1) a new spectral-spatial classification approach to generate feature representation for hyperspectral image, (2) a complementary yet effective feature pooling approach, i.e. the superpixel-based spatial pyramid representation that is used for the spatial correlation study, (3) evaluation on two public hyperspectral image datasets with superior image classification performance.

  6. Organization of visuo-spatial serial memory: interaction of temporal order with spatial and temporal grouping.

    Science.gov (United States)

    Parmentier, Fabrice B R; Andrés, Pilar; Elford, Greg; Jones, Dylan M

    2006-05-01

    This study investigates whether memory for sequences of spatial locations can be represented hierarchically, that is, as successive groups containing the order of constituent locations. Two grouping manipulations are used: Temporal grouping, based on the verbal serial memory literature, and spatial grouping, based on recent empirical work on visuo-spatial serial memory. In Experiment 1, we examine the relationship between spatial grouping and temporal order and showed that recall performance increases when both temporal and spatial organization correlate, but decreases when they clash. Experiments 2 and 3 show that the latter result is confounded by differences in path length (length of spatial path defined by the locations) between conditions, and that no effect of the spatial organization is observed when path length is controlled for. In Experiment 4, an alternative method to spatial grouping, temporal grouping, is used to induce hierarchical organization. A recall advantage is found in the temporal grouping condition. The results suggest that hierarchical representations can be imposed on order information for visuo-spatial sequences, either when participants have pre-existing knowledge about the form of the path formed by the sequence or when temporal boundaries delimit chunks; that increased path length is the cause of the performance decrement observed when dots from separate spatial groups are presented successively; and that path length and more generally sequence characteristics should be taken into account in designing future research on visuo-spatial serial memory.

  7. Sustainable spatial development in higher education

    Directory of Open Access Journals (Sweden)

    Maja Terlević

    2015-06-01

    Full Text Available Sustainable development is not only a great challenge for society as a whole, but also for higher education institutions, which have been rapidly including sustainable development in their educational process in the last two decades. Directly or indirectly, education for sustainable spatial development includes all aspects of sustainable development: environmental, economic, social and cultural. Space is a junction of various interests, which requires coordinating the entire process of spatial planning, taking into account the goal of sustainable spatial development. The existing values of space are insufficient for the rapid implementation of a sustainable spatial development paradigm. Suitable education is needed by both individuals and spatial planning professionals and at all levels of education. It is therefore necessary to transform some of the academic programs in the higher education curriculum by integrating teaching content and methods that include long-term knowledge and holistic thinking, taking into account the importance of interdisciplinary integration. This article reviews literature in sustainable development in higher education from 2002 to 2013. Topics discussed include students’ and teachers’ conceptions of sustainable development, the presence of sustainable development and sustainable spatial development in higher education and the reasons for the slow introduction of this material into the curriculum. Based on a literature analysis, the last section identifies important drivers that can contribute to a more rapid integration of a sustainable spatial development paradigm into higher education.

  8. Bibliography of spatial interferometry in optical astronomy

    Science.gov (United States)

    Gezari, Daniel Y.; Roddier, Francois; Roddier, Claude

    1990-01-01

    The Bibliography of Spatial Interferometry in Optical Astronomy is a guide to the published literature in applications of spatial interferometry techniques to astronomical observations, theory and instrumentation at visible and infrared wavelengths. The key words spatial and optical define the scope of this discipline, distinguishing it from spatial interferometry at radio wavelengths, interferometry in the frequency domain applied to spectroscopy, or more general electro-optics theoretical and laboratory research. The main bibliography is a listing of all technical articles published in the international scientific literature and presented at the major international meetings and workshops attended by the spatial interferometry community. Section B summarizes publications dealing with the basic theoretical concepts and algorithms proposed and applied to optical spatial interferometry and imaging through a turbulent atmosphere. The section on experimental techniques is divided into twelve categories, representing the most clearly identified major areas of experimental research work. Section D, Observations, identifies publications dealing specifically with observations of astronomical sources, in which optical spatial interferometry techniques have been applied.

  9. Abstract spatial reasoning as an autistic strength.

    Directory of Open Access Journals (Sweden)

    Jennifer L Stevenson

    Full Text Available Autistic individuals typically excel on spatial tests that measure abstract reasoning, such as the Block Design subtest on intelligence test batteries and the Raven's Progressive Matrices nonverbal test of intelligence. Such well-replicated findings suggest that abstract spatial processing is a relative and perhaps absolute strength of autistic individuals. However, previous studies have not systematically varied reasoning level--concrete vs. abstract--and test domain--spatial vs. numerical vs. verbal, which the current study did. Autistic participants (N = 72 and non-autistic participants (N = 72 completed a battery of 12 tests that varied by reasoning level (concrete vs. abstract and domain (spatial vs. numerical vs. verbal. Autistic participants outperformed non-autistic participants on abstract spatial tests. Non-autistic participants did not outperform autistic participants on any of the three domains (spatial, numerical, and verbal or at either of the two reasoning levels (concrete and abstract, suggesting similarity in abilities between autistic and non-autistic individuals, with abstract spatial reasoning as an autistic strength.

  10. Abstract spatial reasoning as an autistic strength.

    Science.gov (United States)

    Stevenson, Jennifer L; Gernsbacher, Morton Ann

    2013-01-01

    Autistic individuals typically excel on spatial tests that measure abstract reasoning, such as the Block Design subtest on intelligence test batteries and the Raven's Progressive Matrices nonverbal test of intelligence. Such well-replicated findings suggest that abstract spatial processing is a relative and perhaps absolute strength of autistic individuals. However, previous studies have not systematically varied reasoning level--concrete vs. abstract--and test domain--spatial vs. numerical vs. verbal, which the current study did. Autistic participants (N = 72) and non-autistic participants (N = 72) completed a battery of 12 tests that varied by reasoning level (concrete vs. abstract) and domain (spatial vs. numerical vs. verbal). Autistic participants outperformed non-autistic participants on abstract spatial tests. Non-autistic participants did not outperform autistic participants on any of the three domains (spatial, numerical, and verbal) or at either of the two reasoning levels (concrete and abstract), suggesting similarity in abilities between autistic and non-autistic individuals, with abstract spatial reasoning as an autistic strength.

  11. Eco-spatial Structure of Urban Agglomeration

    Institute of Scientific and Technical Information of China (English)

    GUO Rongchao; MIAO Changhong; LI Xuexin; CHEN Deguang

    2007-01-01

    In terms of ecological theory, this paper makes a comprehensive analysis of the mutualism and coevolutionary mechanism between the eco-spatial structure and socio-economic development ofthe urban agglomeration,and maps out optimized modes of the eco-spatial structure of the urban agglomeration. The analysis is a case study of the urban agglomeration on different levels of global, national, provincial and local scales, on the basis of those conclusions are drawn: 1) Within the scope of the urban agglomeration, the cities should be reasonably sized and appropriately densified; the spatial combination of the urban agglomeration ought to be orderly, and its eco-spatial structure ought to be optimized and efficient; the relationship between the economic society and eco-spatial environment ought to be that of mutual benefit and co-evolution. 2) "The mode of corridor group network" is a certain trend evoked from the spatial structure of urban agglomeration. 3) The eco-spatial structure of urban agglomeration under "the mode of corridor group network" can further increase the environmental capacity of urban agglomeration, and is in favor of the harmonious relationship between man and nature.

  12. Exploring the Structure of Spatial Representations.

    Directory of Open Access Journals (Sweden)

    Tamas Madl

    Full Text Available It has been suggested that the map-like representations that support human spatial memory are fragmented into sub-maps with local reference frames, rather than being unitary and global. However, the principles underlying the structure of these 'cognitive maps' are not well understood. We propose that the structure of the representations of navigation space arises from clustering within individual psychological spaces, i.e. from a process that groups together objects that are close in these spaces. Building on the ideas of representational geometry and similarity-based representations in cognitive science, we formulate methods for learning dissimilarity functions (metrics characterizing participants' psychological spaces. We show that these learned metrics, together with a probabilistic model of clustering based on the Bayesian cognition paradigm, allow prediction of participants' cognitive map structures in advance. Apart from insights into spatial representation learning in human cognition, these methods could facilitate novel computational tools capable of using human-like spatial concepts. We also compare several features influencing spatial memory structure, including spatial distance, visual similarity and functional similarity, and report strong correlations between these dimensions and the grouping probability in participants' spatial representations, providing further support for clustering in spatial memory.

  13. Rasdaman for Big Spatial Raster Data

    Science.gov (United States)

    Hu, F.; Huang, Q.; Scheele, C. J.; Yang, C. P.; Yu, M.; Liu, K.

    2015-12-01

    Spatial raster data have grown exponentially over the past decade. Recent advancements on data acquisition technology, such as remote sensing, have allowed us to collect massive observation data of various spatial resolution and domain coverage. The volume, velocity, and variety of such spatial data, along with the computational intensive nature of spatial queries, pose grand challenge to the storage technologies for effective big data management. While high performance computing platforms (e.g., cloud computing) can be used to solve the computing-intensive issues in big data analysis, data has to be managed in a way that is suitable for distributed parallel processing. Recently, rasdaman (raster data manager) has emerged as a scalable and cost-effective database solution to store and retrieve massive multi-dimensional arrays, such as sensor, image, and statistics data. Within this paper, the pros and cons of using rasdaman to manage and query spatial raster data will be examined and compared with other common approaches, including file-based systems, relational databases (e.g., PostgreSQL/PostGIS), and NoSQL databases (e.g., MongoDB and Hive). Earth Observing System (EOS) data collected from NASA's Atmospheric Scientific Data Center (ASDC) will be used and stored in these selected database systems, and a set of spatial and non-spatial queries will be designed to benchmark their performance on retrieving large-scale, multi-dimensional arrays of EOS data. Lessons learnt from using rasdaman will be discussed as well.

  14. Remote state preparation of spatial qubits

    Energy Technology Data Exchange (ETDEWEB)

    Solis-Prosser, M. A.; Neves, L. [Center for Optics and Photonics, Universidad de Concepcion, Casilla 4016, Concepcion (Chile) and Departamento de Fisica, Universidad de Concepcion, Casilla 160-C, Concepcion (Chile)

    2011-07-15

    We study the quantum communication protocol of remote state preparation (RSP) for pure states of qubits encoded in single photons transmitted through a double slit, the so-called spatial qubits. Two measurement strategies that one can adopt to remotely prepare the states are discussed. The first strategy is the well-known spatial postselection, where a single-pixel detector measures the transverse position of the photon between the focal and the image plane of a lens. The second strategy, proposed by ourselves, is a generalized measurement divided into two steps: the implementation of a two-outcome positive operator-valued measurement (POVM) followed by the spatial postselection at the focal plane of the lens by a two-pixel detector in each output of the POVM. In both cases we analyze the effects of the finite spatial resolution of the detectors over three figures of merit of the protocol, namely, the probability of preparation, the fidelity, and purity of the remotely prepared states. It is shown that our strategy improves these figures compared with spatial postselection, at the expense of increasing the classical communication cost as well as the required experimental resources. In addition, we present a modified version of our strategy for RSP of spatial qudits which is able to prepare arbitrary pure states, unlike spatial postselection alone. We expect that our study may also be extended for RSP of the angular spectrum of a single-photon field as an alternative for quantum teleportation which requires very inefficient nonlinear interactions.

  15. Spatial Inferences in Narrative Comprehension: the Role of Verbal and Spatial Working Memory.

    Science.gov (United States)

    Irrazabal, Natalia; Burin, Debora

    2016-01-01

    During the comprehension of narrative texts, readers keep a mental representation of the location of protagonists and objects; a breach in spatial coherence is detected by longer online reading times (consistency effect). We addressed whether these spatial inferences involve verbal or spatial working memory in two experiments, combining the consistency paradigm with selective verbal and spatial working memory concurrent tasks. The first experiment found longer reading times with a concurrent spatial task under imagery instructions (t33 = 2.87, p = .021). The second experiment, under comprehension reading instructions, found effects of verbal interference on reading times and accuracy. With a verbal secondary task, reading times for the target sentence were shorter (t45 = 3.60, p = .004) and the error rate was significantly higher (t47 = 2.95, p = .005) than without interference. This pattern of results suggests that spatial inferences in narrative comprehension rely mainly on verbal resources, and spatial working memory resources are recruited when imagery is required.

  16. Spatial short-term memory in children with nonverbal learning disabilities: impairment in encoding spatial configuration.

    Science.gov (United States)

    Narimoto, Tadamasa; Matsuura, Naomi; Takezawa, Tomohiro; Mitsuhashi, Yoshinori; Hiratani, Michio

    2013-01-01

    The authors investigated whether impaired spatial short-term memory exhibited by children with nonverbal learning disabilities is due to a problem in the encoding process. Children with or without nonverbal learning disabilities performed a simple spatial test that required them to remember 3, 5, or 7 spatial items presented simultaneously in random positions (i.e., spatial configuration) and to decide if a target item was changed or all items including the target were in the same position. The results showed that, even when the spatial positions in the encoding and probe phases were similar, the mean proportion correct of children with nonverbal learning disabilities was 0.58 while that of children without nonverbal learning disabilities was 0.84. The authors argue with the results that children with nonverbal learning disabilities have difficulty encoding relational information between spatial items, and that this difficulty is responsible for their impaired spatial short-term memory.

  17. Semantic Metadata for Heterogeneous Spatial Planning Documents

    Science.gov (United States)

    Iwaniak, A.; Kaczmarek, I.; Łukowicz, J.; Strzelecki, M.; Coetzee, S.; Paluszyński, W.

    2016-09-01

    Spatial planning documents contain information about the principles and rights of land use in different zones of a local authority. They are the basis for administrative decision making in support of sustainable development. In Poland these documents are published on the Web according to a prescribed non-extendable XML schema, designed for optimum presentation to humans in HTML web pages. There is no document standard, and limited functionality exists for adding references to external resources. The text in these documents is discoverable and searchable by general-purpose web search engines, but the semantics of the content cannot be discovered or queried. The spatial information in these documents is geographically referenced but not machine-readable. Major manual efforts are required to integrate such heterogeneous spatial planning documents from various local authorities for analysis, scenario planning and decision support. This article presents results of an implementation using machine-readable semantic metadata to identify relationships among regulations in the text, spatial objects in the drawings and links to external resources. A spatial planning ontology was used to annotate different sections of spatial planning documents with semantic metadata in the Resource Description Framework in Attributes (RDFa). The semantic interpretation of the content, links between document elements and links to external resources were embedded in XHTML pages. An example and use case from the spatial planning domain in Poland is presented to evaluate its efficiency and applicability. The solution enables the automated integration of spatial planning documents from multiple local authorities to assist decision makers with understanding and interpreting spatial planning information. The approach is equally applicable to legal documents from other countries and domains, such as cultural heritage and environmental management.

  18. Spatial occupancy models for large data sets

    Science.gov (United States)

    Johnson, Devin S.; Conn, Paul B.; Hooten, Mevin B.; Ray, Justina C.; Pond, Bruce A.

    2013-01-01

    Since its development, occupancy modeling has become a popular and useful tool for ecologists wishing to learn about the dynamics of species occurrence over time and space. Such models require presence–absence data to be collected at spatially indexed survey units. However, only recently have researchers recognized the need to correct for spatially induced overdisperison by explicitly accounting for spatial autocorrelation in occupancy probability. Previous efforts to incorporate such autocorrelation have largely focused on logit-normal formulations for occupancy, with spatial autocorrelation induced by a random effect within a hierarchical modeling framework. Although useful, computational time generally limits such an approach to relatively small data sets, and there are often problems with algorithm instability, yielding unsatisfactory results. Further, recent research has revealed a hidden form of multicollinearity in such applications, which may lead to parameter bias if not explicitly addressed. Combining several techniques, we present a unifying hierarchical spatial occupancy model specification that is particularly effective over large spatial extents. This approach employs a probit mixture framework for occupancy and can easily accommodate a reduced-dimensional spatial process to resolve issues with multicollinearity and spatial confounding while improving algorithm convergence. Using open-source software, we demonstrate this new model specification using a case study involving occupancy of caribou (Rangifer tarandus) over a set of 1080 survey units spanning a large contiguous region (108 000 km2) in northern Ontario, Canada. Overall, the combination of a more efficient specification and open-source software allows for a facile and stable implementation of spatial occupancy models for large data sets.

  19. SEMANTIC METADATA FOR HETEROGENEOUS SPATIAL PLANNING DOCUMENTS

    Directory of Open Access Journals (Sweden)

    A. Iwaniak

    2016-09-01

    Full Text Available Spatial planning documents contain information about the principles and rights of land use in different zones of a local authority. They are the basis for administrative decision making in support of sustainable development. In Poland these documents are published on the Web according to a prescribed non-extendable XML schema, designed for optimum presentation to humans in HTML web pages. There is no document standard, and limited functionality exists for adding references to external resources. The text in these documents is discoverable and searchable by general-purpose web search engines, but the semantics of the content cannot be discovered or queried. The spatial information in these documents is geographically referenced but not machine-readable. Major manual efforts are required to integrate such heterogeneous spatial planning documents from various local authorities for analysis, scenario planning and decision support. This article presents results of an implementation using machine-readable semantic metadata to identify relationships among regulations in the text, spatial objects in the drawings and links to external resources. A spatial planning ontology was used to annotate different sections of spatial planning documents with semantic metadata in the Resource Description Framework in Attributes (RDFa. The semantic interpretation of the content, links between document elements and links to external resources were embedded in XHTML pages. An example and use case from the spatial planning domain in Poland is presented to evaluate its efficiency and applicability. The solution enables the automated integration of spatial planning documents from multiple local authorities to assist decision makers with understanding and interpreting spatial planning information. The approach is equally applicable to legal documents from other countries and domains, such as cultural heritage and environmental management.

  20. Spatial patterns of mortality in Bangladesh.

    Science.gov (United States)

    Sharif, A H; Huq, S M; Mesbah-us-Saleheen

    1993-05-01

    This paper depicts the spatial patterns of mortality of the administrative upazilas of Bangladesh. Due to the absence of adequate data on mortality rates from across the country, the mortality rates of the upazilas are calculated from the age sex structure of the population of the respective upazilas employing the standardized mortality rates of divisional headquarters. Crude death rates are used to determine spatial patterns of mortality in Bangladesh. The patterns portray strong regional differences. Such differentiation is accounted for by traditional differences in demographic and socio-economic factors. Also, regression analysis is used to assist in explaining spatial variations.

  1. Strategic Spatial Planning as Persuasive Storytelling

    DEFF Research Database (Denmark)

    Olesen, Kristian

    the persuasive power of spatial concepts in bringing transport infrastructure projects onto the national political agenda. In conclusion, the paper calls for critical attention to the rationalities underpinning practices of persuasive storytelling in contemporary strategic spatial planning.......The paper analyses how the spatial vision of the Loop City for the Øresund Region has played an important persuasive role in legitimizing and mobilizing local and national political support for a light rail project along the outer ring road in the Greater Copenhagen Area. The paper discusses...

  2. Spatial data exploratory analysis and usability

    Directory of Open Access Journals (Sweden)

    D Josselin

    2003-02-01

    Full Text Available In this article, we intend to show how useful Exploratory Spatial Data Analysis is in improving spatial data usability. We first outlined a general framework about usability using conceptual modelling, including Data, Users and Methodologies. We then defined keywords into classes and their relations. A central ternary relation is enhanced to describe usability. In the second section, we present ESDA with its fundamental basics: i.e. robustness and way(s to handle data and related graphic tools. We also described the software package ARPEGE'. Through a concrete example, we demonstrate and discuss its relevance for exploratory spatial data analysis and usability.

  3. Spatial Analysis Methods of Road Traffic Collisions

    DEFF Research Database (Denmark)

    Loo, Becky P. Y.; Anderson, Tessa Kate

    Spatial Analysis Methods of Road Traffic Collisions centers on the geographical nature of road crashes, and uses spatial methods to provide a greater understanding of the patterns and processes that cause them. Written by internationally known experts in the field of transport geography, the book...... outlines the key issues in identifying hazardous road locations (HRLs), considers current approaches used for reducing and preventing road traffic collisions, and outlines a strategy for improved road safety. The book covers spatial accuracy, validation, and other statistical issues, as well as link...

  4. The Europeanisation of spatial planning in Britain

    DEFF Research Database (Denmark)

    Richardson, Tim; Jensen, Ole B.

    This paper explores the representation of European space in images, and the significance of these images in building and reproducing policy discourses of European space. Images are understood as elements of an emerging transnational spatial policy discourse, and so are analysed in the context...... of contestation over meanings, played out in policy debates, in documentation and in other practices of spatial planning. In particular we concentrate on how images are used together with textual references and discussions to form a persuasive component of spatial discourse. We therefore analyse...

  5. Evaluating spatial patterns in hydrological modelling

    DEFF Research Database (Denmark)

    Koch, Julian

    is not fully exploited by current modelling frameworks due to the lack of suitable spatial performance metrics. Furthermore, the traditional model evaluation using discharge is found unsuitable to lay confidence on the predicted catchment inherent spatial variability of hydrological processes in a fully...... the contiguous United Sates (10^6 km2). To this end, the thesis at hand applies a set of spatial performance metrics on various hydrological variables, namely land-surface-temperature (LST), evapotranspiration (ET) and soil moisture. The inspiration for the applied metrics is found in related fields...

  6. A Spatial Calculus of Wrapped Compartments

    CERN Document Server

    Bioglio, Livio; Coppo, Mario; Damiani, Ferruccio; Sciacca, Eva; Spinella, Salvatore; Troina, Angelo

    2011-01-01

    The Calculus of Wrapped Compartments (CWC) is a recently proposed modelling language for the representation and simulation of biological systems behaviour. Although CWC has no explicit structure modelling a spatial geometry, its compartment labelling feature can be exploited to model various examples of spatial interactions in a natural way. However, specifying large networks of compartments may require a long modelling phase. In this work we present a surface language for CWC that provides basic constructs for modelling spatial interactions. These constructs can be compiled away to obtain a standard CWC model, thus exploiting the existing CWC simulation tool. A case study concerning the modelling of Arbuscular Mychorrizal fungi growth is discussed.

  7. The Biggest Myth in Spatial Econometrics

    Directory of Open Access Journals (Sweden)

    James P. LeSage

    2014-12-01

    Full Text Available There is near universal agreement that estimates and inferences from spatial regression models are sensitive to particular specifications used for the spatial weight structure in these models. We find little theoretical basis for this commonly held belief, if estimates and inferences are based on the true partial derivatives for a well-specified spatial regression model. We conclude that this myth may have arisen from past applied work that incorrectly interpreted the model coefficients as if they were partial derivatives, or from use of misspecified models.

  8. Hierarchical modeling and analysis for spatial data

    CERN Document Server

    Banerjee, Sudipto; Gelfand, Alan E

    2003-01-01

    Among the many uses of hierarchical modeling, their application to the statistical analysis of spatial and spatio-temporal data from areas such as epidemiology And environmental science has proven particularly fruitful. Yet to date, the few books that address the subject have been either too narrowly focused on specific aspects of spatial analysis, or written at a level often inaccessible to those lacking a strong background in mathematical statistics.Hierarchical Modeling and Analysis for Spatial Data is the first accessible, self-contained treatment of hierarchical methods, modeling, and dat

  9. Characteristic Spatial Scales in Earthquake Data

    CERN Document Server

    Zöller, G; Hainzl, S; Kurths, J

    1997-01-01

    We present a new technique in order to quantify the dynamics of spatially extended systems. Using a test on the existence of unstable periodic orbits, we identify intermediate spatial scales, wherein the dynamics is characterized by maximum nontrivial determinism. This method is applied to earthquake catalogues containing time, coordinates and magnitude. As a result we extract a set of areas with significant deterministic and low-dimensional dynamics from the data. Finally, a simple model is used to show that these scales can be interpreted as local spatial coupling strengths.

  10. Engineering the spatial organization of metabolic pathways

    DEFF Research Database (Denmark)

    Albertsen, Line; Maury, Jerome; Bach, Lars Stougaard;

    does however often depend on both heterologous and host enzymes. In this case, no spatial coordination of the biosynthetic enzymes can be expected to be in place. Presumably this contributes to the low productivity regularly observed for heterologous pathways. In one test case, we investigated whether...... of the spatial organization of biosynthetic pathways. Several natural systems for ensuring optimal spatial arrangement of biosynthetic enzymes exist. Sequentially acting enzymes can for example be positioned in close proximity by attachment to cellular structures, up-concentration in membrane enclosed organelles......, as enzyme fusion combined with down-regulation of a competing pathway and up-regulation of a selected pathway enzyme resulted in a five-fold higher sesquiterpene production. This simple test case demonstrates that engineering of the spatial organization of pathways has great potential for diverting flux...

  11. Spatial relational memory requires hippocampal adult neurogenesis.

    Directory of Open Access Journals (Sweden)

    David Dupret

    Full Text Available The dentate gyrus of the hippocampus is one of the few regions of the mammalian brain where new neurons are generated throughout adulthood. This adult neurogenesis has been proposed as a novel mechanism that mediates spatial memory. However, data showing a causal relationship between neurogenesis and spatial memory are controversial. Here, we developed an inducible transgenic strategy allowing specific ablation of adult-born hippocampal neurons. This resulted in an impairment of spatial relational memory, which supports a capacity for flexible, inferential memory expression. In contrast, less complex forms of spatial knowledge were unaltered. These findings demonstrate that adult-born neurons are necessary for complex forms of hippocampus-mediated learning.

  12. Navigation in spatial networks: A survey

    Science.gov (United States)

    Huang, Wei; Chen, Shengyong; Wang, Wanliang

    2014-01-01

    The study on the navigation process in spatial networks has attracted much attention in recent years due to the universal applications in real communication networks. This article surveys recent advances of the navigation problem in spatial networks. Due to the ability to overcome scaling limitations in utilizing geometric information for designing navigation algorithms in spatial networks, we summarize here several important navigation algorithms based on geometric information on both homogeneous and heterogeneous spatial networks. Due to the geometric distance employed, the cost associated with the lengths of additional long-range connections is also taken into account in this survey. Therefore, some contributions reporting how the distribution of long-range links’ lengths affects the average navigation time are summarized. We also briefly discuss two other related processes, i.e. the random walk process and the transportation process. Finally, a few open discussions are included at the end of this survey.

  13. Statistics of spatially integrated speckle intensity difference

    DEFF Research Database (Denmark)

    Hanson, Steen Grüner; Yura, Harold

    2009-01-01

    We consider the statistics of the spatially integrated speckle intensity difference obtained from two separated finite collecting apertures. For fully developed speckle, closed-form analytic solutions for both the probability density function and the cumulative distribution function are derived...

  14. City of Zagreb Spatial Data Infrastructure

    Directory of Open Access Journals (Sweden)

    Darko Šiško

    2011-12-01

    Full Text Available Through the establishment of the Coordination Group for the City of Zagreb Spatial Management IT System, the City of Zagreb has become actively involved in the wider global community by setting up the Zagreb Spatial Data Infrastructure (ZSDI service. In the City of Zagreb, many bodies of city administration use and create spatial data and services daily in their work. All are ZSDI users and obviously have to make data mutually available. Without spatial data and services, it would be impossible to manage space effectively, plan city development, monitor the situation on the ground, or carry out many other activities. This paper gives an overview of ZSDI set-up activities so far, as well as plans for the future. 

  15. ARC Code TI: SLAB Spatial Audio Renderer

    Data.gov (United States)

    National Aeronautics and Space Administration — SLAB is a software-based, real-time virtual acoustic environment rendering system being developed as a tool for the study of spatial hearing. SLAB is designed to...

  16. Data management on the spatial web

    DEFF Research Database (Denmark)

    Jensen, Christian S.

    2012-01-01

    billion web queries are issued that have local intent and target spatial web objects. These are points of interest with a web presence, and they thus have locations as well as textual descriptions. This development has given prominence to spatial web data management, an area ripe with new and exciting...... opportunities and challenges. The research community has embarked on inventing and supporting new query functionality for the spatial web. Different kinds of spatial web queries return objects that are near a location argument and are relevant to a text argument. To support such queries, it is important...... functionality enabled by the setting. Further, the talk offers insight into the data management techniques capable of supporting such functionality....

  17. The spatial industrial organization of innovation

    NARCIS (Netherlands)

    Bruijn, P.J.M. de

    2010-01-01

    This study offers insight in spatial dimensions of innovation. It combines insights gained from economic geography (territorial innovation models and the geography of innovation), industrial organization (transaction cost economics and the competence-based approach) and international business manage

  18. Spatial Scaling of Land Cover Networks

    CERN Document Server

    Small, Christopher

    2015-01-01

    Spatial networks of land cover are well-described by power law rank-size distributions. Continuous field proxies for human settlements, agriculture and forest cover have similar spatial scaling properties spanning 4 to 5 orders of magnitude. Progressive segmentation of these continuous fields yields spatial networks with rank-size distributions having slopes near -1 for a wide range of thresholds. We consider a general explanation for this scaling that does not require different processes for each type of land cover. The same conditions that give rise to scale-free networks in general can produce power law distributions of component sizes for bounded spatial networks confined to a plane or surface. Progressive segmentation of a continuous field naturally results in growth of the network while the increasing perimeters of the growing components result in preferential attachment to the larger components with the longer perimeters. Progressive segmentation of two types of random continuous field results in progr...

  19. Language and Spatial Cognition in Route Navigation

    Institute of Scientific and Technical Information of China (English)

    宋娟

    2013-01-01

    The purpose of this study is to investigate the contrast between using street names or landmarks to process spatial in⁃structions. The study confirms the special cognitive status of landmarks in the mental representation of routes.

  20. The Spatial Context of Residential Segregation

    CERN Document Server

    Roberto, Elizabeth

    2015-01-01

    Scholars have engaged in a longstanding debate about how best to measure residential segregation, and scores of indexes have been developed in response. However, the methods commonly employed are aspatial -- they summarize the characteristics of segregation patterns, such as concentration or clustering, but ignore their spatial features, such as how neighborhoods are spatially arranged. As a consequence, many studies find the same level of segregation whether a city has a patchwork of racial and ethnic enclaves, or is divided into large areas with little or no diversity. New methods have been developed to capture the spatial proximity of neighborhoods and the geographic scale of clustering. However, they lack a realistic measure of distance and do not accurately represent how segregation varies within cities. In this paper, I introduce a new method for studying the spatial context of residential segregation. I measure the distance between locations along city roads rather than in a straight line. Road distanc...

  1. Coping with uncertainties in integrative spatial planning

    NARCIS (Netherlands)

    Dijst, M.J.; Burrough, P.A.; Schot, P.P.

    2005-01-01

    As a consequence of economic, technological, and sociocultural megatrends,Western countries are increasingly being confronted with large spatial problems. Households and businesses need more space for residential, recreational, and economic activities. An increasing demand for mobility of persons an

  2. Partially coherent imaging and spatial coherence wavelets

    CERN Document Server

    Castaneda, R

    2003-01-01

    A description of spatially partially coherent imaging based on the propagation of second order spatial coherence wavelets and marginal power spectra (Wigner distribution functions) is presented. In this dynamics, the spatial coherence wavelets will be affected by the system through its elementary transfer function. The consistency of the model with the both extreme cases of full coherent and incoherent imaging was proved. In the last case we obtained the classical concept of optical transfer function as a simple integral of the elementary transfer function. Furthermore, the elementary incoherent response function was introduced as the Fourier transform of the elementary transfer function. It describes the propagation of spatial coherence wavelets form each object point to each image point through a specific point on the pupil planes. The point spread function of the system was obtained by a simple integral of the elementary incoherent response function.

  3. Cooperative Spatial Retreat for Resilient Drone Networks.

    Science.gov (United States)

    Kang, Jin-Hyeok; Kwon, Young-Min; Park, Kyung-Joon

    2017-05-03

    Drones are broadening their scope to various applications such as networking, package delivery, agriculture, rescue, and many more. For proper operation of drones, reliable communication should be guaranteed because drones are remotely controlled. When drones experience communication failure due to bad channel condition, interference, or jamming in a certain area, one existing solution is to exploit mobility or so-called spatial retreat to evacuate them from the communication failure area. However, the conventional spatial retreat scheme moves drones in random directions, which results in inefficient movement with significant evacuation time and waste of battery lifetime. In this paper, we propose a novel spatial retreat technique that takes advantage of cooperation between drones for resilient networking, which is called cooperative spatial retreat (CSR). Our performance evaluation shows that the proposed CSR significantly outperforms existing schemes.

  4. On spatially explicit models of cholera epidemics

    National Research Council Canada - National Science Library

    Bertuzzo, E; Casagrandi, R; Gatto, M; Rodriguez-Iturbe, I; Rinaldo, A

    2010-01-01

    We generalize a recently proposed model for cholera epidemics that accounts for local communities of susceptibles and infectives in a spatially explicit arrangement of nodes linked by networks having...

  5. Action comprehension: deriving spatial and functional relations.

    Science.gov (United States)

    Bach, Patric; Knoblich, Günther; Gunter, Thomas C; Friederici, Angela D; Prinz, Wolfgang

    2005-06-01

    A perceived action can be understood only when information about the action carried out and the objects used are taken into account. It was investigated how spatial and functional information contributes to establishing these relations. Participants observed static frames showing a hand wielding an instrument and a potential target object of the action. The 2 elements could either match or mismatch, spatially or functionally. Participants were required to judge only 1 of the 2 relations while ignoring the other. Both irrelevant spatial and functional mismatches affected judgments of the relevant relation. Moreover, the functional relation provided a context for the judgment of the spatial relation but not vice versa. The results are discussed in respect to recent accounts of action understanding. ((c) 2005 APA, all rights reserved).

  6. Pulse shaping using a spatial light modulator

    CSIR Research Space (South Africa)

    Botha, N

    2009-07-01

    Full Text Available Femtosecond pulse shaping can be done by different kinds of pulse shapers, such as liquid crystal spatial light modulators (LC SLM), acousto optic modulators (AOM) and deformable and movable mirrors. A few applications where pulse shaping...

  7. Vacation homes, spatial planning and sustainability

    DEFF Research Database (Denmark)

    Xue, Jin

    2014-01-01

    patterns of vacation homes are highly relevant to environmental sustainability. Unlike the spatial planning for urban areas where the urban environmental problamatique has been highly recognized and theories of sustainable urban development and planning relatively fully developed, vacation home has been...... a missing component in sustainable spatial development and planning both in theories and practice. Moreover, spatial planning for urban areas and vacation homes cannot be separated as they mutually influence each other. Against this background, the paper is concerned with how and to what extent concerns...... on sustainability of vacation homes is integrated into the spatial planning in the Danish context. The lack of ontological and theoretical debates on the environmental sustainability of vacation homes will be reflected upon before investigating the Danish case. A deep realist approach is adopted to explore...

  8. Bias Corrected Spatially Downscaled Monthly Climate Predictions

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This archive contains fine spatial-resolution translations of 112 contemporary climate projections over the contiguous United States. The original projections are...

  9. Lectures on Topics in Spatial Stochastic Processes

    CERN Document Server

    Capasso, Vincenzo; Ivanoff, B Gail; Dozzi, Marco; Dalang, Robert C; Mountford, Thomas S

    2003-01-01

    The theory of stochastic processes indexed by a partially ordered set has been the subject of much research over the past twenty years. The objective of this CIME International Summer School was to bring to a large audience of young probabilists the general theory of spatial processes, including the theory of set-indexed martingales and to present the different branches of applications of this theory, including stochastic geometry, spatial statistics, empirical processes, spatial estimators and survival analysis. This theory has a broad variety of applications in environmental sciences, social sciences, structure of material and image analysis. In this volume, the reader will find different approaches which foster the development of tools to modelling the spatial aspects of stochastic problems.

  10. SIMULATION MODELING SLOW SPATIALLY HETER- OGENEOUS COAGULATION

    Directory of Open Access Journals (Sweden)

    P. A. Zdorovtsev

    2013-01-01

    Full Text Available A new model of spatially inhomogeneous coagulation, i.e. formation of larger clusters by joint interaction of smaller ones, is under study. The results of simulation are compared with known analytical and numerical solutions.

  11. Coping with uncertainties in integrative spatial planning

    NARCIS (Netherlands)

    Dijst, M.J.; Burrough, P.A.; Schot, P.P.

    2005-01-01

    As a consequence of economic, technological, and sociocultural megatrends,Western countries are increasingly being confronted with large spatial problems. Households and businesses need more space for residential, recreational, and economic activities. An increasing demand for mobility of persons

  12. [Prediction of spatial distribution of forest carbon storage in Heilongjiang Province using spatial error model].

    Science.gov (United States)

    Liu, Chang; Li, Feng-Ri; Zhen, Zhen

    2014-10-01

    Abstract: Based on the data from Chinese National Forest Inventory (CNFI) and Key Ecological Benefit Forest Monitoring plots (5075 in total) in Heilongjiang Province in 2010 and concurrent meteorological data coming from 59 meteorological stations located in Heilongjiang, Jilin and Inner Mongolia, this paper established a spatial error model (SEM) by GeoDA using carbon storage as dependent variable and several independent variables, including diameter of living trees (DBH), number of trees per hectare (TPH), elevation (Elev), slope (Slope), and product of precipitation and temperature (Rain_Temp). Global Moran's I was computed for describing overall spatial autocorrelations of model results at different spatial scales. Local Moran's I was calculated at the optimal bandwidth (25 km) to present spatial distribution residuals. Intra-block spatial variances were computed to explain spatial heterogeneity of residuals. Finally, a spatial distribution map of carbon storage in Heilongjiang was visualized based on predictions. The results showed that the distribution of forest carbon storage in Heilongjiang had spatial effect and was significantly influenced by stand, topographic and meteorological factors, especially average DBH. SEM could solve the spatial autocorrelation and heterogeneity well. There were significant spatial differences in distribution of forest carbon storage. The carbon storage was mainly distributed in Zhangguangcai Mountain, Xiao Xing'an Mountain and Da Xing'an Mountain where dense, forests existed, rarely distributed in Songnen Plains, while Wanda Mountain had moderate-level carbon storage.

  13. Hedonic approaches based on spatial econometrics and spatial statistics: application to evaluation of project benefits

    Science.gov (United States)

    Tsutsumi, Morito; Seya, Hajime

    2009-12-01

    This study discusses the theoretical foundation of the application of spatial hedonic approaches—the hedonic approach employing spatial econometrics or/and spatial statistics—to benefits evaluation. The study highlights the limitations of the spatial econometrics approach since it uses a spatial weight matrix that is not employed by the spatial statistics approach. Further, the study presents empirical analyses by applying the Spatial Autoregressive Error Model (SAEM), which is based on the spatial econometrics approach, and the Spatial Process Model (SPM), which is based on the spatial statistics approach. SPMs are conducted based on both isotropy and anisotropy and applied to different mesh sizes. The empirical analysis reveals that the estimated benefits are quite different, especially between isotropic and anisotropic SPM and between isotropic SPM and SAEM; the estimated benefits are similar for SAEM and anisotropic SPM. The study demonstrates that the mesh size does not affect the estimated amount of benefits. Finally, the study provides a confidence interval for the estimated benefits and raises an issue with regard to benefit evaluation.

  14. Spatial dynamics of airborne infectious diseases

    OpenAIRE

    Robinson, M; Stilianakis, N. I.; Drossinos, Y.

    2011-01-01

    Disease outbreaks, such as those of Severe Acute Respiratory Syndrome in 2003 and the 2009 pandemic A(H1N1) influenza, have highlighted the potential for airborne transmission in indoor environments. Respirable pathogen-carrying droplets provide a vector for the spatial spread of infection with droplet transport determined by diffusive and convective processes. An epidemiological model describing the spatial dynamics of disease transmission is presented. The effects of an ambient airflow, as ...

  15. Spatial entanglement of nonvacuum Gaussian states

    OpenAIRE

    Kiałka, Filip; Ahmadi, Mehdi; Dragan, Andrzej

    2016-01-01

    The vacuum state of a relativistic quantum field contains entanglement between regions separated by spacelike intervals. Such spatial entanglement can be revealed using an operational method introduced in Ann. Phys. 351, 112 (2014), Phys. Rev. D 91, 016005 (2014). In this approach, a cavity is instantaneously divided into halves by an introduction of an extra perfect mirror. Causal separation of the two regions of the cavity reveals nonlocal spatial correlations present in the field, which ca...

  16. Supporting Visual Problem Solving in Spatial Hypertext

    OpenAIRE

    Hsieh, Haowei; Shipman, Frank

    2009-01-01

    This paper describes the VITE system, a spatial hypertext system that supports two-way mapping for projecting structured information to a two-dimensional workspace and updating the structured information based on user interactions in the workspace. VITE uses information visualization techniques to render structured information in the workspace and provides users an environment to interact with digital information in a spatial hypertext setting. The two-way mapping connects the objects in the ...

  17. Bayesian Spatial Modelling with R-INLA

    OpenAIRE

    Finn Lindgren; Håvard Rue

    2015-01-01

    The principles behind the interface to continuous domain spatial models in the R- INLA software package for R are described. The integrated nested Laplace approximation (INLA) approach proposed by Rue, Martino, and Chopin (2009) is a computationally effective alternative to MCMC for Bayesian inference. INLA is designed for latent Gaussian models, a very wide and flexible class of models ranging from (generalized) linear mixed to spatial and spatio-temporal models. Combined with the stochastic...

  18. Spatially Assisted Schwinger Mechanism and Magnetic Catalysis

    CERN Document Server

    Copinger, Patrick

    2016-01-01

    Using the worldline formalism we compute an effective action for fermions under a temporally modulated electric field and a spatially modulated magnetic field. It is known that the former leads to an enhanced Schwinger Mechanism, while we find that the latter can also result in enhanced particle production and even cause a reorganization of the vacuum to acquire a larger dynamical mass in equilibrium which spatially assists the Magnetic Catalysis.

  19. Spatially Assisted Schwinger Mechanism and Magnetic Catalysis

    Science.gov (United States)

    Copinger, Patrick; Fukushima, Kenji

    2016-08-01

    Using the worldline formalism we compute an effective action for fermions under a temporally modulated electric field and a spatially modulated magnetic field. It is known that the former leads to an enhanced Schwinger mechanism, while we find that the latter can also result in enhanced particle production and even cause a reorganization of the vacuum to acquire a larger dynamical mass in equilibrium which spatially assists the magnetic catalysis.

  20. Spatial Thinking: Precept for Understanding Operational Environments

    Science.gov (United States)

    2016-06-10

    studying how the brain processes spatial stimuli from human senses. Temple University psychologist Nora Newcomb stated that with GPS “you are just...processes relationships between objects in space in an effort to foster awareness for spatial thinking’s influence on problem solving.19 Psychologists ...component, each discipline represents space differently. Philosophers and psychologists use words as tools, astronomers and physicists use mathematics

  1. Residual analysis for spatial point processes

    DEFF Research Database (Denmark)

    Waagepetersen, Rasmus Plenge

    2005-01-01

    Discussion of the paper "Residual analysis for spatial point processes" by A. Baddeley, M. Hazelton, J. Møller and R. Turner. Journal of the Royal Statistical Society, Series B, vol. 67, pages 617-666, 2005.......Discussion of the paper "Residual analysis for spatial point processes" by A. Baddeley, M. Hazelton, J. Møller and R. Turner. Journal of the Royal Statistical Society, Series B, vol. 67, pages 617-666, 2005....

  2. Spatially Assisted Schwinger Mechanism and Magnetic Catalysis.

    Science.gov (United States)

    Copinger, Patrick; Fukushima, Kenji

    2016-08-19

    Using the worldline formalism we compute an effective action for fermions under a temporally modulated electric field and a spatially modulated magnetic field. It is known that the former leads to an enhanced Schwinger mechanism, while we find that the latter can also result in enhanced particle production and even cause a reorganization of the vacuum to acquire a larger dynamical mass in equilibrium which spatially assists the magnetic catalysis.

  3. Spatial solitons in nonlinear liquid waveguides

    Indian Academy of Sciences (India)

    R Barillé; G Rivoire

    2001-11-01

    Spatial solitons are studied in a planar waveguide filled with nonlinear liquids. Spectral and spatial measurements for different geometries and input power of the laser beam show the influence of different nonlinear effects as stimulated scatterings on the soliton propagation and in particular on the beam polarization. The stimulated scattering can be used advantageously to couple the two polarization components. This effect can lead to multiple applications in optical switching.

  4. Integrated statistical modelling of spatial landslide probability

    Science.gov (United States)

    Mergili, M.; Chu, H.-J.

    2015-09-01

    Statistical methods are commonly employed to estimate spatial probabilities of landslide release at the catchment or regional scale. Travel distances and impact areas are often computed by means of conceptual mass point models. The present work introduces a fully automated procedure extending and combining both concepts to compute an integrated spatial landslide probability: (i) the landslide inventory is subset into release and deposition zones. (ii) We employ a simple statistical approach to estimate the pixel-based landslide release probability. (iii) We use the cumulative probability density function of the angle of reach of the observed landslide pixels to assign an impact probability to each pixel. (iv) We introduce the zonal probability i.e. the spatial probability that at least one landslide pixel occurs within a zone of defined size. We quantify this relationship by a set of empirical curves. (v) The integrated spatial landslide probability is defined as the maximum of the release probability and the product of the impact probability and the zonal release probability relevant for each pixel. We demonstrate the approach with a 637 km2 study area in southern Taiwan, using an inventory of 1399 landslides triggered by the typhoon Morakot in 2009. We observe that (i) the average integrated spatial landslide probability over the entire study area corresponds reasonably well to the fraction of the observed landside area; (ii) the model performs moderately well in predicting the observed spatial landslide distribution; (iii) the size of the release zone (or any other zone of spatial aggregation) influences the integrated spatial landslide probability to a much higher degree than the pixel-based release probability; (iv) removing the largest landslides from the analysis leads to an enhanced model performance.

  5. Clustering and knowledge discovery in spatial databases

    Science.gov (United States)

    Xu, Xiaowei; Ester, Martin; Kriegel, Hans-Peter; Sander, Jörg

    In the past decades, clustering has been widely used in areas such as pattern recognition, data analysis, and image processing. Recently, clustering has been recognized as a useful method for knowledge discovery in spatial databases. To efficiently detect clusters from large spatial databases with a limited amount of available memory, special database techniques have been developed. In this article, we present a survey of these methods from a database perspective.

  6. Training Spatial Knowledge Acquisition Using Virtual Environments

    Science.gov (United States)

    2008-02-22

    Gauthier, G. M. (1995). Acquisition of Spatial Knowledge Through Visual Exploration of Simulated Environments. Ecological Psychology, 7(1),1. Piaget , J...in Free Recall. Psychological Bulletin, 76(1), 45-48. Seidel, A. D., and Danford, S. (Eds.). (1979). Environmental Design: Research, Theory , and...Skill. In H. L. Pick and L. P. Acredolo (Eds.), Spatial Orientation: Theory , Research, and Application, (pp. 195-217). New York: Plenum Press. Thorndyke

  7. Topological Properties of Spatial Coherence Function

    Institute of Scientific and Technical Information of China (English)

    REN Ji-Rong; ZHU Tao; DUAN Yi-Shi

    2008-01-01

    The topological properties of the spatial coherence function are investigated rigorously.The phase singular structures(coherence vortices)of coherence function can be naturally deduced from the topological current,which is an abstract mathematical object studied previously.We find that coherence vortices are characterized by the Hopf index and Brouwer degree in topology.The coherence flux quantization and the linking of the closed coherence vortices are also studied from the topological properties of the spatial coherence function.

  8. Multivariate semiparametric spatial methods for imaging data.

    Science.gov (United States)

    Chen, Huaihou; Cao, Guanqun; Cohen, Ronald A

    2017-04-01

    Univariate semiparametric methods are often used in modeling nonlinear age trajectories for imaging data, which may result in efficiency loss and lower power for identifying important age-related effects that exist in the data. As observed in multiple neuroimaging studies, age trajectories show similar nonlinear patterns for the left and right corresponding regions and for the different parts of a big organ such as the corpus callosum. To incorporate the spatial similarity information without assuming spatial smoothness, we propose a multivariate semiparametric regression model with a spatial similarity penalty, which constrains the variation of the age trajectories among similar regions. The proposed method is applicable to both cross-sectional and longitudinal region-level imaging data. We show the asymptotic rates for the bias and covariance functions of the proposed estimator and its asymptotic normality. Our simulation studies demonstrate that by borrowing information from similar regions, the proposed spatial similarity method improves the efficiency remarkably. We apply the proposed method to two neuroimaging data examples. The results reveal that accounting for the spatial similarity leads to more accurate estimators and better functional clustering results for visualizing brain atrophy pattern.Functional clustering; Longitudinal magnetic resonance imaging (MRI); Penalized B-splines; Region of interest (ROI); Spatial penalty.

  9. Spatial reference in multiple object tracking.

    Science.gov (United States)

    Jahn, Georg; Papenmeier, Frank; Meyerhoff, Hauke S; Huff, Markus

    2012-01-01

    Spatial reference in multiple object tracking is available from configurations of dynamic objects and static reference objects. In three experiments, we studied the use of spatial reference in tracking and in relocating targets after abrupt scene rotations. Observers tracked 1, 2, 3, 4, and 6 targets in 3D scenes, in which white balls moved on a square floor plane. The floor plane was either visible thus providing static spatial reference or it was invisible. Without scene rotations, the configuration of dynamic objects provided sufficient spatial reference and static spatial reference was not advantageous. In contrast, with abrupt scene rotations of 20°, static spatial reference supported in relocating targets. A wireframe floor plane lacking local visual detail was as effective as a checkerboard. Individually colored geometric forms as static reference objects provided no additional benefit either, even if targets were centered on these forms at the abrupt scene rotation. Individualizing the dynamic objects themselves by color for a brief interval around the abrupt scene rotation, however, did improve performance. We conclude that attentional tracking of moving targets proceeds within dynamic configurations but detached from static local background.

  10. Spatial methods for deriving crop rotation history

    Science.gov (United States)

    Mueller-Warrant, George W.; Trippe, Kristin M.; Whittaker, Gerald W.; Anderson, Nicole P.; Sullivan, Clare S.

    2017-08-01

    Benefits of converting 11 years of remote sensing classification data into cropping history of agricultural fields included measuring lengths of rotation cycles and identifying specific sequences of intervening crops grown between final years of old grass seed stands and establishment of new ones. Spatial and non-spatial methods were complementary. Individual-year classification errors were often correctable in spreadsheet-based non-spatial analysis, whereas their presence in spatial data generally led to exclusion of fields from further analysis. Markov-model testing of non-spatial data revealed that year-to-year cropping sequences did not match average frequencies for transitions among crops grown in western Oregon, implying that rotations into new grass seed stands were influenced by growers' desires to achieve specific objectives. Moran's I spatial analysis of length of time between consecutive grass seed stands revealed that clustering of fields was relatively uncommon, with high and low value clusters only accounting for 7.1 and 6.2% of fields.

  11. The spatial patterns of directional phenotypic selection

    KAUST Repository

    Siepielski, Adam M.

    2013-09-12

    Local adaptation, adaptive population divergence and speciation are often expected to result from populations evolving in response to spatial variation in selection. Yet, we lack a comprehensive understanding of the major features that characterise the spatial patterns of selection, namely the extent of variation among populations in the strength and direction of selection. Here, we analyse a data set of spatially replicated studies of directional phenotypic selection from natural populations. The data set includes 60 studies, consisting of 3937 estimates of selection across an average of five populations. We performed meta-analyses to explore features characterising spatial variation in directional selection. We found that selection tends to vary mainly in strength and less in direction among populations. Although differences in the direction of selection occur among populations they do so where selection is often weakest, which may limit the potential for ongoing adaptive population divergence. Overall, we also found that spatial variation in selection appears comparable to temporal (annual) variation in selection within populations; however, several deficiencies in available data currently complicate this comparison. We discuss future research needs to further advance our understanding of spatial variation in selection. © 2013 John Wiley & Sons Ltd/CNRS.

  12. Self-locomotion and spatial language and spatial cognition: insights from typical and atypical development.

    Science.gov (United States)

    Oudgenoeg-Paz, Ora; Rivière, James

    2014-01-01

    Various studies have shown that occurrence of locomotion in infancy is correlated with the development of spatial cognitive competencies. Recent evidence suggests that locomotor experience might also be important for the development of spatial language. Together these findings suggest that locomotor experience might play a crucial role in the development of linguistic-cognitive spatial skills. However, some studies indicate that, despite their total deprivation of locomotor experience, young children with spinal muscular atrophy (SMA) have the capacity to acquire and use rich spatial representations including good spatial language. Nonetheless, we have to be cautious about what the striking performances displayed by SMA children can reveal on the link between motor and spatial development, as the dynamics of brain development in atypically developing children are different from typically developing children.

  13. [Effects of spatial heterogeneity on spatial extrapolation of sampling plot data].

    Science.gov (United States)

    Liang, Yu; He, Hong-Shi; Hu, Yuan-Man; Bu, Ren-Cang

    2012-01-01

    By using model combination method, this paper simulated the changes of response variable (tree species distribution area at landscape level under climate change) under three scenarios of environmental spatial heterogeneous level, analyzed the differentiation of simulated results under different scenarios, and discussed the effects of environmental spatial heterogeneity on the larger spatial extrapolation of the tree species responses to climate change observed in sampling plots. For most tree species, spatial heterogeneity had little effects on the extrapolation from plot scale to class scale; for the tree species insensitive to climate warming and the azonal species, spatial heterogeneity also had little effects on the extrapolation from plot-scale to zonal scale. By contrast, for the tree species sensitive to climate warming, spatial heterogeneity had effects on the extrapolation from plot scale to zonal scale, and the effects could be varied under different scenarios.

  14. Emergence of overlap in ensembles of spatial multiplexes and statistical mechanics of spatial interacting networks ensembles

    CERN Document Server

    Halu, Arda; Bianconi, Ginestra

    2013-01-01

    Spatial networks range from the brain networks, to transportation networks and infrastructures. Recently interacting and multiplex networks are attracting great attention because their dynamics and robustness cannot be understood without treating at the same time several networks. Here we present maximal entropy ensembles of spatial multiplex and spatial interacting networks that can be used in order to model spatial multilayer network structures and to build null models of real datasets. We show that spatial multiplex naturally develop a significant overlap of the links, a noticeable property of many multiplexes that can affect significantly the dynamics taking place on them. Additionally, we characterize ensembles of spatial interacting networks and we analyse the structure of interacting airport and railway networks in India, showing the effect of space in determining the link probability.

  15. Developing a modelling for the spatial data infrastructure

    CSIR Research Space (South Africa)

    Hjelmager, J

    2005-07-01

    Full Text Available The Commission on Spatial Data Standards of the International Cartographic Association (ICA) is working on defining spatial models and technical characteristics of a Spatial Data Infrastructure (SDI). To date, this work has been restricted...

  16. Self-locomotion and spatial language and spatial cognition: insights from typical and atypical development

    OpenAIRE

    Ora eOudgenoeg-Paz; James eRivière

    2014-01-01

    Various studies have shown that occurrence of locomotion in infancy is correlated with the development of spatial cognitive competencies. Recent evidence suggests that locomotor experience might also be important for the development of spatial language. Together these findings suggest that locomotor experience might play a crucial role in the development of linguistic-cognitive spatial skills. However, some studies indicate that, despite their total deprivation of locomotor experience, young ...

  17. Spatial positioning : method development for spatial analysis of interaction in buildings

    OpenAIRE

    Markhede, Henrik

    2010-01-01

    In offices, knowledge sharing largely depends on everyday face-to-face interaction patterns. These interaction patterns may depend on how employees move through the office space. This thesis explores how these spatial relations influence individual choices with respect to employee movements or routes. Space syntax related research has shown a strong relationship between spatial configuration and pedestrian movement in cities, yet field of space syntax has not applied spatial analysis to the o...

  18. Coefficient shifts in geographical ecology: an empirical evaluation of spatial and non-spatial regression

    OpenAIRE

    Bini, L. Mauricio; Diniz-Filho, J. Alexandre F.; Rangel, Thiago F. L. V. B.; Akre, Thomas S. B.; Albaladejo, Rafael G.; Albuquerque, Fabio S.; Aparicio, Abelardo; Araújo, Miguel B.; Baselga, Andrés; Beck, Jan; Bellocq, M. Isabel; Böhning-Gaese, Katrin; Paulo A V Borges; Castro-Parga, Isabel; Chey, Vun Khen

    2009-01-01

    A major focus of geographical ecology and macroecology is to understand the causes of spatially structured ecological patterns. However, achieving this understanding can be complicated when using multiple regression, because the relative importance of explanatory variables, as measured by regression coefficients, can shift depending on whether spatially explicit or non-spatial modeling is used. However, the extent to which coefficients may shift and why shifts occur are unclear. H...

  19. Research of ERP model system of spatial data warehouse

    Institute of Scientific and Technical Information of China (English)

    CHEN Xue-long; WANG Yan-zhang

    2004-01-01

    The broad sharing of spatial information is demanded in the infrastructure construction of spatial data in our country. And the spatial data warehouse realizes the effective management and sharing of spatial information serving as an efficient tool. This article proposes ERP model system that of general-decision-oriented for constructing spatial data warehouse from the aspect of decision application. In the end of article, the construction process of spatial data warehouse based on ERP model system is discussed.

  20. From Spatial Intelligence to Spatial Competences: The Results of Applied Geo-Research in Italian Schools

    Directory of Open Access Journals (Sweden)

    Emilia SARNO

    2012-08-01

    Full Text Available This contribution explains the connection between spatial intelligence and spatial competences and by indicating how the first is the cognitive matrix of abilities necessary to move in space as well as to represent it. Indeed, two are principal factors involved in the spatial intelligence: orientation and representation. Both are based on a close interaction between spatial thought and movement in space. I show the basic features of spatial intelligence through the analysis of specialist literature. This point, however, requires a further step to be taken into consideration: how can spatial intelligence be strengthened together with the related spatial competences? Moreover, which branch of knowledge is the most suitable to do so? By referring to the existing literature on the subject, we would like to indicate that geography has a pre-eminent role in dealing with the connection between man and space and as such it is the most suitable academic discipline to aid the development of spatial abilities through a series of precise didactic activities. The second part of this paper presents an experimental prototype of this kind of targeted teaching activity following the research-action method, an approach where theory and practice meet allowing a systematic collection of data. In effect, the stages of an experimental framework which has allowed the spatial intelligence of primary school children to be developed has been described and the methods of monitoring the results have also be illustrated.

  1. Spatial contiguity analysis. A method for describing spatial structures of seismic data

    Energy Technology Data Exchange (ETDEWEB)

    Faraj, A. [Institut Francais du Petrole, 1-4 Av. de Bois-Preau, 92500 Rueil Malmaison, Paris (France); Cailly, F. [Beicip Franlab, 232 Av. Napoleon Bonaparte, 92500 Rueil Malmaison, Paris (France)

    2001-11-01

    We apply spatial contiguity analysis (SCA) to study spatial structures contained in seismic images. Compared to classical methods, such as principal component analysis (PCA), SCA is more efficient for multivariate description and spatial filtering of this kind of images. We present SCA according to geostatistic formalism defined by Matheron. A preliminary spatial analysis of initial variables is required. Made with the help of variogram curves, this permits to underline spatial properties of these variables and defines contiguity distance and direction to apply SCA. A series of mathematical tools is defined. They allow quantifying the information held by initial variables and factorial components in terms of variance and spatial variability and exhibit data spatial structures on different scales. The method is applied to analyse a seismic data set. We compare PCA and SCA results. This data set gives us the opportunity to show the interest of preliminary spatial analysis of initial variables, and the effects of spatial direction and distance on the data decomposition in elementary structures.

  2. Global Data Spatially Interrelate System for Scientific Big Data Spatial-Seamless Sharing

    Science.gov (United States)

    Yu, J.; Wu, L.; Yang, Y.; Lei, X.; He, W.

    2014-04-01

    A good data sharing system with spatial-seamless services will prevent the scientists from tedious, boring, and time consuming work of spatial transformation, and hence encourage the usage of the scientific data, and increase the scientific innovation. Having been adopted as the framework of Earth datasets by Group on Earth Observation (GEO), Earth System Spatial Grid (ESSG) is potential to be the spatial reference of the Earth datasets. Based on the implementation of ESSG, SDOG-ESSG, a data sharing system named global data spatially interrelate system (GASE) was design to make the data sharing spatial-seamless. The architecture of GASE was introduced. The implementation of the two key components, V-Pools, and interrelating engine, and the prototype is presented. Any dataset is firstly resampled into SDOG-ESSG, and is divided into small blocks, and then are mapped into hierarchical system of the distributed file system in V-Pools, which together makes the data serving at a uniform spatial reference and at a high efficiency. Besides, the datasets from different data centres are interrelated by the interrelating engine at the uniform spatial reference of SDOGESSG, which enables the system to sharing the open datasets in the internet spatial-seamless.

  3. Spatial Thinking in Atmospheric Science Education

    Science.gov (United States)

    McNeal, P. M.; Petcovic, H. L.; Ellis, T. D.

    2016-12-01

    Atmospheric science is a STEM discipline that involves the visualization of three-dimensional processes from two-dimensional maps, interpretation of computer-generated graphics and hand plotting of isopleths. Thus, atmospheric science draws heavily upon spatial thinking. Research has shown that spatial thinking ability can be a predictor of early success in STEM disciplines and substantial evidence demonstrates that spatial thinking ability is improved through various interventions. Therefore, identification of the spatial thinking skills and cognitive processes used in atmospheric science is the first step toward development of instructional strategies that target these skills and scaffold the learning of students in atmospheric science courses. A pilot study of expert and novice meteorologists identified mental animation and disembedding as key spatial skills used in the interpretation of multiple weather charts and images. Using this as a starting point, we investigated how these spatial skills, together with expertise, domain specific knowledge, and working memory capacity affect the ability to produce an accurate forecast. Participants completed a meteorology concept inventory, experience questionnaire and psychometric tests of spatial thinking ability and working memory capacity prior to completing a forecasting task. A quantitative analysis of the collected data investigated the effect of the predictor variables on the outcome task. A think-aloud protocol with individual participants provided a qualitative look at processes such as task decomposition, rule-based reasoning and the formation of mental models in an attempt to understand how individuals process this complex data and describe outcomes of particular meteorological scenarios. With our preliminary results we aim to inform atmospheric science education from a cognitive science perspective. The results point to a need to collaborate with the atmospheric science community broadly, such that multiple

  4. Spatial probability aids visual stimulus discrimination

    Directory of Open Access Journals (Sweden)

    Michael Druker

    2010-08-01

    Full Text Available We investigated whether the statistical predictability of a target's location would influence how quickly and accurately it was classified. Recent results have suggested that spatial probability can be a cue for the allocation of attention in visual search. One explanation for probability cuing is spatial repetition priming. In our two experiments we used probability distributions that were continuous across the display rather than relying on a few arbitrary screen locations. This produced fewer spatial repeats and allowed us to dissociate the effect of a high probability location from that of short-term spatial repetition. The task required participants to quickly judge the color of a single dot presented on a computer screen. In Experiment 1, targets were more probable in an off-center hotspot of high probability that gradually declined to a background rate. Targets garnered faster responses if they were near earlier target locations (priming and if they were near the high probability hotspot (probability cuing. In Experiment 2, target locations were chosen on three concentric circles around fixation. One circle contained 80% of targets. The value of this ring distribution is that it allowed for a spatially restricted high probability zone in which sequentially repeated trials were not likely to be physically close. Participant performance was sensitive to the high-probability circle in addition to the expected effects of eccentricity and the distance to recent targets. These two experiments suggest that inhomogeneities in spatial probability can be learned and used by participants on-line and without prompting as an aid for visual stimulus discrimination and that spatial repetition priming is not a sufficient explanation for this effect. Future models of attention should consider explicitly incorporating the probabilities of targets locations and features.

  5. The Spatial Business Landscape of India

    Directory of Open Access Journals (Sweden)

    Eric Vaz

    2013-12-01

    Full Text Available India has in the last decade become of the fastest growing entrepreneurial landscapes in the world. With a total population of almost 1.2 billion inhabitants, it has developed from a rural economy into a highly competitive market. This study analyses the spatial configuration across the country from a regional perspective, offering an assessment of the spatial autocorrelation of business as to understand the spatial configuration of what I define as a regional-spatial business landscape. In this study, the patterns of distribution of all the registered Indian businesses are assessed counting a total of 6500 registered businesses from 1850 to 2010, which were geocoded and imported into a Geographic Information System environment. A geostatistical analysis is conducted measuring business growth and performance at a national level by means of a Global Moran’s I calculation and followed by assembling a Local Getis-Ord for regional assessment of correlation of road networks. These local spatial statistics reveal clustering of hot spots within threshold distances of road concentrations, suggesting a positive relation between location of businesses and concentration of road networks. The agglomeration of Indian businesses becomes defined by the importance of road infrastructures to allow commutes and interaction of businesses. As a result, it becomes possible to see that India’s business landscape is far from homogenous, and responds well to Weber’s theory of industrial agglomeration, while predicting possible interfirm collaboration. These business hubs in the business landscape are assessed at national level through spatial autocorrelation and then regionally diagnosed by identifying hot spots of business location given business density, and bringing to light the precise location of India’s business hubs from a spatial business landscape perspective at present.

  6. Method of construction spatial transition curve

    Directory of Open Access Journals (Sweden)

    S.V. Didanov

    2013-04-01

    Full Text Available Purpose. The movement of rail transport (speed rolling stock, traffic safety, etc. is largely dependent on the quality of the track. In this case, a special role is the transition curve, which ensures smooth insertion of the transition from linear to circular section of road. The article deals with modeling of spatial transition curve based on the parabolic distribution of the curvature and torsion. This is a continuation of research conducted by the authors regarding the spatial modeling of curved contours. Methodology. Construction of the spatial transition curve is numerical methods for solving nonlinear integral equations, where the initial data are taken coordinate the starting and ending points of the curve of the future, and the inclination of the tangent and the deviation of the curve from the tangent plane at these points. System solutions for the numerical method are the partial derivatives of the equations of the unknown parameters of the law of change of torsion and length of the transition curve. Findings. The parametric equations of the spatial transition curve are calculated by finding the unknown coefficients of the parabolic distribution of the curvature and torsion, as well as the spatial length of the transition curve. Originality. A method for constructing the spatial transition curve is devised, and based on this software geometric modeling spatial transition curves of railway track with specified deviations of the curve from the tangent plane. Practical value. The resulting curve can be applied in any sector of the economy, where it is necessary to ensure a smooth transition from linear to circular section of the curved space bypass. An example is the transition curve in the construction of the railway line, road, pipe, profile, flat section of the working blades of the turbine and compressor, the ship, plane, car, etc.

  7. Spatial Heterogeneity of Vegetation in China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The spatial heterogeneity and ecological characteristics of 74 vegetation types and the lack of vegetation type within the 9.6 million km2 of Chinese territory were studied using data from the China vegetation map. The analysis used 877 large quadrats 10 mm×10 mm (actual size 100 km×100 km), which covered about 8.77 million km2. Each large-quadrat was divided into four small 5 mm×5 mm quadrats (actual size 50 km×50 km). The frequency of occurrence of all vegetation types was recorded in each small quadrat.The survey using the Shiyomi method of vegetation analysis based on the beta-binomial distribution was adopted to describe the frequency of occurrence and spatial heterogeneity for each kind of vegetation. The weighted average heterogeneity of all the vegetation types in the landscape provides a measure of the landscape level heterogeneity which describes the spatial intricacy of the existing vegetation composition.The maximum spatial vegetation heterogeneity was 0.8620 in the frigid-temperate coniferous forest of Larix(V1), which dominates cold moist northeast China. The minimum spatial heterogeneity with a low occurrence was the Caragana tibetica in the gravel desert in the western Yellow River Hetao area. The minimum occurrence with a low spatial heterogeneity was the Monsoon rainforest on rock in Guangxi and Yunnan Provinces. The vegetation types on the Qing-Zang Plateau were found to be representative of Chinese vegetation because of the very high occurrence and spatial heterogeneity of these vegetation types. The weighted average of the heterogeneity was 0.677, while the vegetation diversity index was 3.29.

  8. Design & implementation of distributed spatial computing node based on WPS

    Science.gov (United States)

    Liu, Liping; Li, Guoqing; Xie, Jibo

    2014-03-01

    Currently, the research work of SIG (Spatial Information Grid) technology mostly emphasizes on the spatial data sharing in grid environment, while the importance of spatial computing resources is ignored. In order to implement the sharing and cooperation of spatial computing resources in grid environment, this paper does a systematical research of the key technologies to construct Spatial Computing Node based on the WPS (Web Processing Service) specification by OGC (Open Geospatial Consortium). And a framework of Spatial Computing Node is designed according to the features of spatial computing resources. Finally, a prototype of Spatial Computing Node is implemented and the relevant verification work under the environment is completed.

  9. Research on spatial association rules mining in two-direction

    Institute of Scientific and Technical Information of China (English)

    XUE Li-xia; WANG Zuo-cheng

    2007-01-01

    In data mining from transaction DB, the relationships between the attributes have been focused, but the relationships between the tuples have not been taken into account. In spatial database, there are relationships between the attributes and the tuples, and most of the associations occur between the tuples, such as adjacent, intersection, overlap and other topological relationships. So the tasks of spatial data association rules mining include mining the relationships between attributes of spatial objects, which are called as vertical direction DM, and the relationships between the tuples, which are called as horizontal direction DM. This paper analyzes the storage models of spatial data, uses for reference the technologies of data mining in transaction DB, defines the spatial data association rule, including vertical direction association rule, horizontal direction association rule and two-direction association rule, discusses the measurement of spatial association rule interestingness, and puts forward the work flows of spatial association rule data mining. During two-direction spatial association rules mining, an algorithm is proposed to get non-spatial itemsets. By virtue of spatial analysis, the spatial relations were transferred into non-spatial associations and the non-spatial itemsets were gotten. Based on the non-spatial itemsets, the Apriori algorithm or other algorithms could be used to get the frequent itemsets and then the spatial association rules come into being. Using spatial DB, the spatial association rules were gotten to validate the algorithm, and the test results show that this algorithm is efficient and can mine the interesting spatial rules.

  10. Spatial cluster detection using dynamic programming

    Directory of Open Access Journals (Sweden)

    Sverchkov Yuriy

    2012-03-01

    Full Text Available Abstract Background The task of spatial cluster detection involves finding spatial regions where some property deviates from the norm or the expected value. In a probabilistic setting this task can be expressed as finding a region where some event is significantly more likely than usual. Spatial cluster detection is of interest in fields such as biosurveillance, mining of astronomical data, military surveillance, and analysis of fMRI images. In almost all such applications we are interested both in the question of whether a cluster exists in the data, and if it exists, we are interested in finding the most accurate characterization of the cluster. Methods We present a general dynamic programming algorithm for grid-based spatial cluster detection. The algorithm can be used for both Bayesian maximum a-posteriori (MAP estimation of the most likely spatial distribution of clusters and Bayesian model averaging over a large space of spatial cluster distributions to compute the posterior probability of an unusual spatial clustering. The algorithm is explained and evaluated in the context of a biosurveillance application, specifically the detection and identification of Influenza outbreaks based on emergency department visits. A relatively simple underlying model is constructed for the purpose of evaluating the algorithm, and the algorithm is evaluated using the model and semi-synthetic test data. Results When compared to baseline methods, tests indicate that the new algorithm can improve MAP estimates under certain conditions: the greedy algorithm we compared our method to was found to be more sensitive to smaller outbreaks, while as the size of the outbreaks increases, in terms of area affected and proportion of individuals affected, our method overtakes the greedy algorithm in spatial precision and recall. The new algorithm performs on-par with baseline methods in the task of Bayesian model averaging. Conclusions We conclude that the dynamic

  11. Compatible Spatial Discretizations for Partial Differential Equations

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, Douglas, N, ed.

    2004-11-25

    From May 11--15, 2004, the Institute for Mathematics and its Applications held a hot topics workshop on Compatible Spatial Discretizations for Partial Differential Equations. The numerical solution of partial differential equations (PDE) is a fundamental task in science and engineering. The goal of the workshop was to bring together a spectrum of scientists at the forefront of the research in the numerical solution of PDEs to discuss compatible spatial discretizations. We define compatible spatial discretizations as those that inherit or mimic fundamental properties of the PDE such as topology, conservation, symmetries, and positivity structures and maximum principles. A wide variety of discretization methods applied across a wide range of scientific and engineering applications have been designed to or found to inherit or mimic intrinsic spatial structure and reproduce fundamental properties of the solution of the continuous PDE model at the finite dimensional level. A profusion of such methods and concepts relevant to understanding them have been developed and explored: mixed finite element methods, mimetic finite differences, support operator methods, control volume methods, discrete differential forms, Whitney forms, conservative differencing, discrete Hodge operators, discrete Helmholtz decomposition, finite integration techniques, staggered grid and dual grid methods, etc. This workshop seeks to foster communication among the diverse groups of researchers designing, applying, and studying such methods as well as researchers involved in practical solution of large scale problems that may benefit from advancements in such discretizations; to help elucidate the relations between the different methods and concepts; and to generally advance our understanding in the area of compatible spatial discretization methods for PDE. Particular points of emphasis included: + Identification of intrinsic properties of PDE models that are critical for the fidelity of numerical

  12. Analysis of Spatial Disparities and Driving Factors of Energy Consumption Change in China Based on Spatial Statistics

    OpenAIRE

    Hualin Xie; Guiying Liu; Qu Liu; Peng Wang

    2014-01-01

    The changes of spatial pattern in energy consumption have an impact on global climate change. Based on the spatial autocorrelation analysis and the auto-regression model of spatial statistics, this study has explored the spatial disparities and driving forces in energy consumption changes in China. The results show that the global spatial autocorrelation of energy consumption change in China is significant during the period 1990–2010, and the trend of spatial clustering of energy consumption ...

  13. Dynamic Shortest Path Monitoring in Spatial Networks

    Institute of Scientific and Technical Information of China (English)

    Shuo Shang; Lisi Chen; Zhe-Wei Wei; Dan-Huai Guo; Ji-Rong Wen

    2016-01-01

    With the increasing availability of real-time traffic information, dynamic spatial networks are pervasive nowa-days and path planning in dynamic spatial networks becomes an important issue. In this light, we propose and investigate a novel problem of dynamically monitoring shortest paths in spatial networks (DSPM query). When a traveler aims to a des-tination, his/her shortest path to the destination may change due to two reasons: 1) the travel costs of some edges have been updated and 2) the traveler deviates from the pre-planned path. Our target is to accelerate the shortest path computing in dynamic spatial networks, and we believe that this study may be useful in many mobile applications, such as route planning and recommendation, car navigation and tracking, and location-based services in general. This problem is challenging due to two reasons: 1) how to maintain and reuse the existing computation results to accelerate the following computations, and 2) how to prune the search space effectively. To overcome these challenges, filter-and-refinement paradigm is adopted. We maintain an expansion tree and define a pair of upper and lower bounds to prune the search space. A series of optimization techniques are developed to accelerate the shortest path computing. The performance of the developed methods is studied in extensive experiments based on real spatial data.

  14. Colorful ESL Test Papers And Spatial Intelligence:

    Directory of Open Access Journals (Sweden)

    Dennis Moradkhan

    2014-11-01

    Full Text Available The purpose of this research was to find out whether introducing color as an element which may appeal to spatially-intelligent candidates affects their performance on ESL grammar tests. 52 participants were given two parallel grammar tests, one in black and white and the other bearing the full spectrum of colors in the natural daylight. In order to identify the candidates with visual-spatial learning style, the participants and their teachers were asked to respond to Visual-Spatial Identifier rating scale. Based on the results, no significant relationship was found between the performance of candidates on the colorful and black and white grammar tests and their visual-spatial intelligence. It was concluded that other variables including the method of applying colors, the type and combination of colors as well as the differential impact of different colors on candidates with different cultural backgrounds needed to be addressed before any conclusions can be drawn about the application of color in language assessment. Keywords: assessment, colorful exam papers, multiple intelligences, spatial intelligence

  15. Spatial stochastic dynamics enable robust cell polarization.

    Directory of Open Access Journals (Sweden)

    Michael J Lawson

    Full Text Available Although cell polarity is an essential feature of living cells, it is far from being well-understood. Using a combination of computational modeling and biological experiments we closely examine an important prototype of cell polarity: the pheromone-induced formation of the yeast polarisome. Focusing on the role of noise and spatial heterogeneity, we develop and investigate two mechanistic spatial models of polarisome formation, one deterministic and the other stochastic, and compare the contrasting predictions of these two models against experimental phenotypes of wild-type and mutant cells. We find that the stochastic model can more robustly reproduce two fundamental characteristics observed in wild-type cells: a highly polarized phenotype via a mechanism that we refer to as spatial stochastic amplification, and the ability of the polarisome to track a moving pheromone input. Moreover, we find that only the stochastic model can simultaneously reproduce these characteristics of the wild-type phenotype and the multi-polarisome phenotype of a deletion mutant of the scaffolding protein Spa2. Significantly, our analysis also demonstrates that higher levels of stochastic noise results in increased robustness of polarization to parameter variation. Furthermore, our work suggests a novel role for a polarisome protein in the stabilization of actin cables. These findings elucidate the intricate role of spatial stochastic effects in cell polarity, giving support to a cellular model where noise and spatial heterogeneity combine to achieve robust biological function.

  16. Detecting spatial regimes in ecosystems | Science Inventory ...

    Science.gov (United States)

    Research on early warning indicators has generally focused on assessing temporal transitions with limited application of these methods to detecting spatial regimes. Traditional spatial boundary detection procedures that result in ecoregion maps are typically based on ecological potential (i.e. potential vegetation), and often fail to account for ongoing changes due to stressors such as land use change and climate change and their effects on plant and animal communities. We use Fisher information, an information theory based method, on both terrestrial and aquatic animal data (US Breeding Bird Survey and marine zooplankton) to identify ecological boundaries, and compare our results to traditional early warning indicators, conventional ecoregion maps, and multivariate analysis such as nMDS (non-metric Multidimensional Scaling) and cluster analysis. We successfully detect spatial regimes and transitions in both terrestrial and aquatic systems using Fisher information. Furthermore, Fisher information provided explicit spatial information about community change that is absent from other multivariate approaches. Our results suggest that defining spatial regimes based on animal communities may better reflect ecological reality than do traditional ecoregion maps, especially in our current era of rapid and unpredictable ecological change. Use an information theory based method to identify ecological boundaries and compare our results to traditional early warning

  17. Spatial Development Potential Considering Conservation Planning Criteria

    Directory of Open Access Journals (Sweden)

    Dora Tomić

    2011-06-01

    Full Text Available The paper focuses on the issues of possible differences in the decision considering spatial allocation of land use and its potential and optimized allocation that derives from suitability modeling. The researched area was Žumberak- Samoborsko gorje Nature Park, one of the youngest Croatian nature parks. As such, it should have a physical plan of the special features areas, in order to know its potential and limitations. There is no such plan yet, so protection measures and development is relinquished to cities and municipalities, within whose territory the Park is situated. One of the municipalities is Ozalj, and it is used in the paper as an example for the analysis of physical planning approach for Žumberak- Samoborsko gorje Nature Park. By the survey of Physical plan of Ozalj municipality, a random selection was used to choose one activity that was planned in the area and for that activity dual spatial analysis was created. It included spatial attractiveness and vulnerability analysis. The results of the analysis have shown whether, in addition to spatial attractiveness criteria, spatial vulnerability criteria was taken into consideration when deciding on the location for the winter sports center. The analysis has also shown whether the Physical plan was in favor of the municipality development or was the fact that it is a Nature Park, designed as the protected area of natural and cultural values, also considered relevant.

  18. Integrating scientific guidance into marine spatial planning.

    Science.gov (United States)

    Rassweiler, Andrew; Costello, Christopher; Hilborn, Ray; Siegel, David A

    2014-04-22

    Marine spatial planning (MSP), whereby areas of the ocean are zoned for different uses, has great potential to reduce or eliminate conflicts between competing management goals, but only if strategically applied. The recent literature overwhelmingly agrees that including stakeholders in these planning processes is critical to success; but, given the countless alternative ways even simple spatial regulations can be configured, how likely is it that a stakeholder-driven process will generate plans that deliver on the promise of MSP? Here, we use a spatially explicit, dynamic bioeconomic model to show that stakeholder-generated plans are doomed to fail in the absence of strong scientific guidance. While strategically placed spatial regulations can improve outcomes remarkably, the vast majority of possible plans fail to achieve this potential. Surprisingly, existing scientific rules of thumb do little to improve outcomes. Here, we develop an alternative approach in which models are used to identify efficient plans, which are then modified by stakeholders. Even if stakeholders alter these initial proposals considerably, results hugely outperform plans guided by scientific rules of thumb. Our results underscore the importance of spatially explicit dynamic models for the management of marine resources and illustrate how such models can be harmoniously integrated into a stakeholder-driven MSP process.

  19. The development of spatial frequency discrimination.

    Science.gov (United States)

    Patel, Ashna; Maurer, Daphne; Lewis, Terri L

    2010-12-31

    We compared thresholds for discriminating spatial frequency for children aged 5, 7, and 9 years, and adults at two baseline spatial frequencies (1 and 3 cpd). In Experiment 1, the minimum change from baseline necessary to detect a change in spatial frequency from either baseline decreased with age from 34% in 5-year-olds to 11% in 7-year-olds, 8% in 9-year-olds, and 6% in adults. The data were best fit by an exponential function reflecting the rapid improvement in thresholds between 5 and 7 years of age and more gradual improvement thereafter (r(2) = 0.50, p spatial frequencies side by side for an unlimited time. The pattern of development for sensitivity to spatial frequency (this study) resembles those for the development of sensitivity to orientation (T. L. Lewis, S. E. Chong, & D. Maurer, 2009) and contrast (D. Ellemberg, T. L. Lewis, C. H. Lui, & D. Maurer, 1999). The similar patterns are consistent with theories of common underlying mechanisms in primary visual cortex (A. Vincent & D. Regan, 1995; W. Zhu, M. Shelley, & R. Shapley, 2008) and suggest that those mechanisms continue to develop throughout childhood.

  20. Reward expectation influences audiovisual spatial integration.

    Science.gov (United States)

    Bruns, Patrick; Maiworm, Mario; Röder, Brigitte

    2014-08-01

    In order to determine the spatial location of an object that is simultaneously seen and heard, the brain assigns higher weights to the sensory inputs that provide the most reliable information. For example, in the well-known ventriloquism effect, the perceived location of a sound is shifted toward the location of a concurrent but spatially misaligned visual stimulus. This perceptual illusion can be explained by the usually much higher spatial resolution of the visual system as compared to the auditory system. Recently, it has been demonstrated that this cross-modal binding process is not fully automatic, but can be modulated by emotional learning. Here we tested whether cross-modal binding is similarly affected by motivational factors, as exemplified by reward expectancy. Participants received a monetary reward for precise and accurate localization of brief auditory stimuli. Auditory stimuli were accompanied by task-irrelevant, spatially misaligned visual stimuli. Thus, the participants' motivational goal of maximizing their reward was put in conflict with the spatial bias of auditory localization induced by the ventriloquist situation. Crucially, the amounts of expected reward differed between the two hemifields. As compared to the hemifield associated with a low reward, the ventriloquism effect was reduced in the high-reward hemifield. This finding suggests that reward expectations modulate cross-modal binding processes, possibly mediated via cognitive control mechanisms. The motivational significance of the stimulus material, thus, constitutes an important factor that needs to be considered in the study of top-down influences on multisensory integration.

  1. Michelson interferometer based spatial phase shift shearography.

    Science.gov (United States)

    Xie, Xin; Yang, Lianxiang; Xu, Nan; Chen, Xu

    2013-06-10

    This paper presents a simple spatial phase shift shearography based on the Michelson interferometer. The Michelson interferometer based shearographic system has been widely utilized in industry as a practical nondestructive test tool. In the system, the Michelson interferometer is used as a shearing device to generate a shearing distance by tilting a small angle in one of the two mirrors. In fact, tilting the mirror in the Michelson interferometer also generates spatial frequency shift. Based on this feature, we introduce a simple Michelson interferometer based spatial phase shift shearography. The Fourier transform (FT) method is applied to separate the spectrum on the spatial frequency domain. The phase change due to the loading can be evaluated using a properly selected windowed inverse-FT. This system can generate a phase map of shearography by using only a single image. The effects of shearing angle, spatial resolution of couple charge device camera, and filter methods are discussed in detail. The theory and the experimental results are presented.

  2. Spatial averaging infiltration model for layered soil

    Institute of Scientific and Technical Information of China (English)

    HU HePing; YANG ZhiYong; TIAN FuQiang

    2009-01-01

    To quantify the influences of soil heterogeneity on infiltration, a spatial averaging infiltration model for layered soil (SAI model) is developed by coupling the spatial averaging approach proposed by Chen et al. and the Generalized Green-Ampt model proposed by Jia et al. In the SAI model, the spatial heterogeneity along the horizontal direction is described by a probability distribution function, while that along the vertical direction is represented by the layered soils. The SAI model is tested on a typical soil using Monte Carlo simulations as the base model. The results show that the SAI model can directly incorporate the influence of spatial heterogeneity on infiltration on the macro scale. It is also found that the homogeneous assumption of soil hydraulic conductivity along the horizontal direction will overestimate the infiltration rate, while that along the vertical direction will underestimate the infiltration rate significantly during rainstorm periods. The SAI model is adopted in the spatial averaging hydrological model developed by the authors, and the results prove that it can be applied in the macro-scale hydrological and land surface process modeling in a promising way.

  3. Spinach Effects (Amaranthus hybridus on Spatial Memory

    Directory of Open Access Journals (Sweden)

    Intan Leonita

    2015-03-01

    Full Text Available Background: Spatial memory reduction in elderly is predicted to increase up to twice every 20 years. Spinach (Amaranthus hybridus is widely consumed by Indonesian people and is believed to prevent declined spatial memory function. The aim of this study was to determine the effects of spinach on spatial memory in wistar rat induced by diazepam Methods: An experimental study was conducted during the period of October to November 2012 in Pharmacology and Therapy Laboratory, Faculty of Medicine, Universitas Padjadjaran. Twenty five wistar rats were divided into 5 groups; two groups as controls, and 3 groups were given 100, 200, and 400mg/kg BW ethanolic extract of spinach (EESL, respectively. On day 7, group 3, 4, and 5 were given 1 mg/kg BW diazepam injection. Morris water maze tests and calculations of escape latency time (ELT were performed on day 7 and 8. Data were analyzed using analysis of variance (ANOVA and least significance difference (LSD test. Results: On day 7, group 2 experienced acceleration in ELT compared to group 4 and group 5. On day 8, group 2 experienced acceleration in ELT compared to group 3 and group 4. There was no significant increase in spatial memory in group 5 (EESL 400mg/kg BW that due to the use of higher dosage does not always show better results. Conclusions: EESL can prevent impairment of spatial memory with an effective dose of 200 mg/kg BW.

  4. Spatial averaging infiltration model for layered soil

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    To quantify the influences of soil heterogeneity on infiltration, a spatial averaging infiltration model for layered soil (SAI model) is developed by coupling the spatial averaging approach proposed by Chen et al. and the Generalized Green-Ampt model proposed by Jia et al. In the SAI model, the spatial hetero- geneity along the horizontal direction is described by a probability distribution function, while that along the vertical direction is represented by the layered soils. The SAI model is tested on a typical soil using Monte Carlo simulations as the base model. The results show that the SAI model can directly incorporate the influence of spatial heterogeneity on infiltration on the macro scale. It is also found that the homogeneous assumption of soil hydraulic conductivity along the horizontal direction will overes- timate the infiltration rate, while that along the vertical direction will underestimate the infiltration rate significantly during rainstorm periods. The SAI model is adopted in the spatial averaging hydrological model developed by the authors, and the results prove that it can be applied in the macro-scale hy- drological and land surface process modeling in a promising way.

  5. Fusion of spatially separated vowel formant cues.

    Science.gov (United States)

    Takanen, Marko; Raitio, Tuomo; Santala, Olli; Alku, Paavo; Pulkki, Ville

    2013-12-01

    Previous studies on fusion in speech perception have demonstrated the ability of the human auditory system to group separate components of speech-like sounds together and consequently to enable the identification of speech despite the spatial separation between the components. Typically, the spatial separation has been implemented using headphone reproduction where the different components evoke auditory images at different lateral positions. In the present study, a multichannel loudspeaker system was used to investigate whether the correct vowel is identified and whether two auditory events are perceived when a noise-excited vowel is divided into two components that are spatially separated. The two components consisted of the even and odd formants. Both the amount of spatial separation between the components and the directions of the components were varied. Neither the spatial separation nor the directions of the components affected the vowel identification. Interestingly, an additional auditory event not associated with any vowel was perceived at the same time when the components were presented symmetrically in front of the listener. In such scenarios, the vowel was perceived from the direction of the odd formant components.

  6. Active and passive contributions to spatial learning.

    Science.gov (United States)

    Chrastil, Elizabeth R; Warren, William H

    2012-02-01

    It seems intuitively obvious that active exploration of a new environment will lead to better spatial learning than will passive exposure. However, the literature on this issue is decidedly mixed-in part, because the concept itself is not well defined. We identify five potential components of active spatial learning and review the evidence regarding their role in the acquisition of landmark, route, and survey knowledge. We find that (1) idiothetic information in walking contributes to metric survey knowledge, (2) there is little evidence as yet that decision making during exploration contributes to route or survey knowledge, (3) attention to place-action associations and relevant spatial relations contributes to route and survey knowledge, although landmarks and boundaries appear to be learned without effort, (4) route and survey information are differentially encoded in subunits of working memory, and (5) there is preliminary evidence that mental manipulation of such properties facilitates spatial learning. Idiothetic information appears to be necessary to reveal the influence of attention and, possibly, decision making in survey learning, which may explain the mixed results in desktop virtual reality. Thus, there is indeed an active advantage in spatial learning, which manifests itself in the task-dependent acquisition of route and survey knowledge.

  7. Spatial Relation Predicates in Topographic Feature Semantics

    Science.gov (United States)

    Varanka, Dalia E.; Caro, Holly K.

    2013-01-01

    Topographic data are designed and widely used for base maps of diverse applications, yet the power of these information sources largely relies on the interpretive skills of map readers and relational database expert users once the data are in map or geographic information system (GIS) form. Advances in geospatial semantic technology offer data model alternatives for explicating concepts and articulating complex data queries and statements. To understand and enrich the vocabulary of topographic feature properties for semantic technology, English language spatial relation predicates were analyzed in three standard topographic feature glossaries. The analytical approach drew from disciplinary concepts in geography, linguistics, and information science. Five major classes of spatial relation predicates were identified from the analysis; representations for most of these are not widely available. The classes are: part-whole (which are commonly modeled throughout semantic and linked-data networks), geometric, processes, human intention, and spatial prepositions. These are commonly found in the ‘real world’ and support the environmental science basis for digital topographical mapping. The spatial relation concepts are based on sets of relation terms presented in this chapter, though these lists are not prescriptive or exhaustive. The results of this study make explicit the concepts forming a broad set of spatial relation expressions, which in turn form the basis for expanding the range of possible queries for topographical data analysis and mapping.

  8. Culturally inconsistent spatial structure reduces learning.

    Science.gov (United States)

    McCrink, Koleen; Shaki, Samuel

    2016-09-01

    Human adults tend to use a spatial continuum to organize any information they consider to be well-ordered, with a sense of initial and final position. The directionality of this spatial mapping is mediated by the culture of the subject, largely as a function of the prevailing reading and writing habits (for example, from left-to-right for English speakers or right-to-left for Hebrew speakers). In the current study, we tasked American and Israeli subjects with encoding and recalling a set of arbitrary pairings, consisting of frequently ordered stimuli (letters with shapes: Experiment 1) or infrequently ordered stimuli (color terms with shapes: Experiment 2), that were serially presented in a left-to-right, right-to-left, or central-only manner. The subjects were better at recalling information that contained ordinal stimuli if the spatial flow of presentation during encoding matched the dominant directionality of the subjects' culture, compared to information encoded in the non-dominant direction. This phenomenon did not extend to infrequently ordered stimuli (e.g., color terms). These findings suggest that adults implicitly harness spatial organization to support memory, and this harnessing process is culturally mediated in tandem with our spatial biases. Published by Elsevier B.V.

  9. Neuroimaging of eye position reveals spatial neglect.

    Science.gov (United States)

    Becker, Elisabeth; Karnath, Hans-Otto

    2010-03-01

    Conjugate eye deviation describes the tonic horizontal deviation of the eyes in acute stroke patients. Here we investigate whether measuring patients' eye-in-head position in clinical magnetic resonance imaging or computed tomography scans obtained at admission shows a specific relationship to spatial neglect. We investigated 124 continuously admitted subjects with unilateral, first-ever left- or right-sided stroke. To control for the possibility that the degree of eye deviation is related to lesion size rather than spatial neglect, overall lesion volume was used as a covariate in the statistical analysis. Horizontal eye-in-head deviation on clinical brain scans appeared to be associated with spatial neglect rather than with brain damage per se. In contrast to the subject groups without the disorder, the patients with spatial neglect showed an eye-in-head position that was significantly deviated towards the ipsilesional right. Evaluation of eye-in-head position on clinical scans thus may be an additional helpful tool for diagnosing spatial neglect, particularly in the very early period of the stroke.

  10. Geo-spatial factors associated with infection risk among young children in rural Ghana: a secondary spatial analysis

    National Research Council Canada - National Science Library

    Aimone, Ashley M; Brown, Patrick E; Zlotkin, Stanley H; Cole, Donald C; Owusu-Agyei, Seth

    2016-01-01

    .... Spatial analyses were conducted using a generalized linear geostatistical model with a Matern spatial correlation function and four definitions of infection status using different combinations of inflammation...

  11. Some topics in the spatial bispectra

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, E. [NUWC, Newport, RI (United States)

    1994-11-15

    The bispectrum can be defined as the triple fourier transform of the third order cumulant of a data series. Up to the present, except in image analysis, most work on the bispectrum has treated time series. Recently, however, there has been interest in using the bispectrum in acoustic array processing. After a look at some issues involving sampling frequencies and symmetries of the bispectrum in general, two applications of the spatial bispectrum to underwater acoustic array processing will be discussed. One is a method of processing against loss of spatial coherence in towed arrays, which takes the form of a one-dimensional image, and the other is a look at the role of spatial bispectra in matched-field processing, which is a form of model-based processing used for the localization of acoustic sound sources.

  12. Testing for Spatial Isotropy Under General Designs.

    Science.gov (United States)

    Maity, Arnab; Sherman, Michael

    2012-05-01

    Spatial modeling is typically composed of a specification of a mean function and a model for the correlation structure. A common assumption on the spatial correlation is that it is isotropic. This means that the correlation between any two observations depends only on the distance between those sites and not on their relative orientation. The assumption of isotropy is often made due to a simpler interpretation of correlation behavior and to an easier estimation problem under an assumed isotropy. The assumption of isotropy, however, can have serious deleterious effects when not appropriate. In this paper we formulate a test of isotropy for spatial observations located according to a general class of stochastic designs. Distribution theory of our test statistic is derived and we carry out extensive simulations which verify the efficacy of our approach. We apply our methodology to a data set on longleaf pine trees from an oldgrowth forest in the southern United States.

  13. Spatial interactions in agent-based modeling

    CERN Document Server

    Ausloos, Marcel; Merlone, Ugo

    2014-01-01

    Agent Based Modeling (ABM) has become a widespread approach to model complex interactions. In this chapter after briefly summarizing some features of ABM the different approaches in modeling spatial interactions are discussed. It is stressed that agents can interact either indirectly through a shared environment and/or directly with each other. In such an approach, higher-order variables such as commodity prices, population dynamics or even institutions, are not exogenously specified but instead are seen as the results of interactions. It is highlighted in the chapter that the understanding of patterns emerging from such spatial interaction between agents is a key problem as much as their description through analytical or simulation means. The chapter reviews different approaches for modeling agents' behavior, taking into account either explicit spatial (lattice based) structures or networks. Some emphasis is placed on recent ABM as applied to the description of the dynamics of the geographical distribution o...

  14. Typograph: Multiscale Spatial Exploration of Text Documents

    Energy Technology Data Exchange (ETDEWEB)

    Endert, Alexander; Burtner, Edwin R.; Cramer, Nicholas O.; Perko, Ralph J.; Hampton, Shawn D.; Cook, Kristin A.

    2013-12-01

    Visualizing large document collections using a spatial layout of terms can enable quick overviews of information. However, these metaphors (e.g., word clouds, tag clouds, etc.) often lack interactivity to explore the information and the location and rendering of the terms are often not based on mathematical models that maintain relative distances from other information based on similarity metrics. Further, transitioning between levels of detail (i.e., from terms to full documents) can be challanging. In this paper, we present Typograph, a multi-scale spatial exploration visualization for large document collections. Based on the term-based visualization methods, Typograh enables multipel levels of detail (terms, phrases, snippets, and full documents) within the single spatialization. Further, the information is placed based on their relative similarity to other information to create the “near = similar” geography metaphor. This paper discusses the design principles and functionality of Typograph and presents a use case analyzing Wikipedia to demonstrate usage.

  15. Structure properties of evolutionary spatially embedded networks

    Science.gov (United States)

    Hui, Z.; Li, W.; Cai, X.; Greneche, J. M.; Wang, Q. A.

    2013-04-01

    This work is a modeling of evolutionary networks embedded in one or two dimensional configuration space. The evolution is based on two attachments depending on degree and spatial distance. The probability for a new node n to connect with a previous node i at distance r follows aki∑jkj+(1-a)rni-α∑jrnj-α, where ki is the degree of node i, α and a are tunable parameters. In spatial driven model (a=0), the spatial distance distribution follows the power-law feature. The mean topological distance l and the clustering coefficient C exhibit phase transitions at same critical values of α which change with the dimensionality d of the embedding space. When a≠0, the degree distribution follows the "shifted power law" (SPL) which interpolates between exponential and scale-free distributions depending on the value of a.

  16. Physical exercise, neuroplasticity, spatial learning and memory.

    Science.gov (United States)

    Cassilhas, Ricardo C; Tufik, Sergio; de Mello, Marco Túlio

    2016-03-01

    There has long been discussion regarding the positive effects of physical exercise on brain activity. However, physical exercise has only recently begun to receive the attention of the scientific community, with major interest in its effects on the cognitive functions, spatial learning and memory, as a non-drug method of maintaining brain health and treating neurodegenerative and/or psychiatric conditions. In humans, several studies have shown the beneficial effects of aerobic and resistance exercises in adult and geriatric populations. More recently, studies employing animal models have attempted to elucidate the mechanisms underlying neuroplasticity related to physical exercise-induced spatial learning and memory improvement, even under neurodegenerative conditions. In an attempt to clarify these issues, the present review aims to discuss the role of physical exercise in the improvement of spatial learning and memory and the cellular and molecular mechanisms involved in neuroplasticity.

  17. Spatial Models and Networks of Living Systems

    DEFF Research Database (Denmark)

    Juul, Jeppe Søgaard

    . Such systems are known to be stabilized by spatial structure. Finally, I analyse data from a large mobile phone network and show that people who are topologically close in the network have similar communication patterns. This main part of the thesis is based on six different articles, which I have co...... variables of the system. However, this approach disregards any spatial structure of the system, which may potentially change the behaviour drastically. An alternative approach is to construct a cellular automaton with nearest neighbour interactions, or even to model the system as a complex network...... with interactions defined by network topology. In this thesis I first describe three different biological models of ageing and cancer, in which spatial structure is important for the system dynamics. I then turn to describe characteristics of ecosystems consisting of three cyclically interacting species...

  18. Statistical Physics of the Spatial Prisoner's Dilemma

    CERN Document Server

    Javarone, Marco Alberto

    2015-01-01

    We introduce an analytical model to study the evolution towards equilibrium in spatial games. In particular, we focus our attention on the spatial Prisoner's Dilemma, as it constitutes an emblematic example of a game whose Nash equilibrium is defection. Previous investigations showed that, under opportune conditions, it is possible to reach, in the evolutionary Prisoner's Dilemma, an equilibrium of cooperation. Notably, it seems that mechanisms like motion may lead a population to become cooperative. In the proposed model, we map agents to particles of a gas so that, on varying the system temperature, they randomly move. In doing so, we are able to identify a relation between the temperature and the final equilibrium of the population, explaining how it is possible to break the classical Nash equilibrium in the spatial Prisoner's Dilemma. Moreover, we introduce a formalism to study order-disorder phase transitions in these dynamics. As result, we highlight that the proposed model allows to explain analyticall...

  19. Spatial segmentation and the black middle class.

    Science.gov (United States)

    Sharkey, Patrick

    2014-01-01

    Ethnographic studies of the black middle class focus attention on the ways in which residential environments condition the experiences of different segments of the black class structure. This study places these arguments in a larger demographic context by providing a national analysis of neighborhood inequality and spatial inequality of different racial and ethnic groups in urban America. The findings show that there has been no change over time in the degree to which majority-black neighborhoods are surrounded by spatial disadvantage. Predominantly black neighborhoods, regardless of socioeconomic composition, continue to be spatially linked with areas of severe disadvantage. However, there has been substantial change in the degree to which middle- and upper-income African-American households have separated themselves from highly disadvantaged neighborhoods. These changes are driven primarily by the growing segment of middle- and upper-income African-Americans living in neighborhoods in which they are not the majority group, both in central cities and in suburbs.

  20. Optical vortex array in spatially varying lattice

    CERN Document Server

    Kapoor, Amit; Senthilkumaran, P; Joseph, Joby

    2015-01-01

    We present an experimental method based on a modified multiple beam interference approach to generate an optical vortex array arranged in a spatially varying lattice. This method involves two steps which are: numerical synthesis of a consistent phase mask by using two-dimensional integrated phase gradient calculations and experimental implementation of produced phase mask by utilizing a phase only spatial light modulator in an optical 4f Fourier filtering setup. This method enables an independent variation of the orientation and period of the vortex lattice. As working examples, we provide the experimental demonstration of various spatially variant optical vortex lattices. We further confirm the existence of optical vortices by formation of fork fringes. Such lattices may find applications in size dependent trapping, sorting, manipulation and photonic crystals.

  1. Test Development Study On The Spatial Visualization

    Directory of Open Access Journals (Sweden)

    Nazan SEZEN YÜKSEL

    2014-12-01

    Full Text Available Spatial visualization, frequently used in many stages of daily life, is also an indispensable part of mathematics and geometry courses. There are many definitions of spatial visualization ability and various tests have been developed to measure this ability. The aim of this study is to develop a new test for determining the spatial visualization ability for students in higher education. For this purpose, a test including 29 items was prepared. The developed test’s pilot scheme was applied to 236 students of mathematics and mathematics education programs in different two state universities. The data obtained were analyzed by packaged software like Iteman 4, SPSS 17.0 and Lisrel8.7. The test, which was developed by discarding two items according to results of item analysis, validity and reliability analysis and confirmatory factor analysis, was finalized. The Cronbach α coefficient of test was calculated as .84 and RMSEA value of test was calculated as 0,032.

  2. The Danish national spatial planning framework

    DEFF Research Database (Denmark)

    Galland, Daniel; Enemark, Stig

    This paper attempts to provide an analysis associated with the performance of the current Danish national spatial planning framework based on a descriptive overview of its changing institutional arrangements and policy instruments. The Danish planning system has been historically qualified...... as holding a comprehensive-integrated character, which depicts a harmonized and coherent institutional and policy framework across different levels of planning administration. However, spatial planning in Denmark has been increasingly exposed to profound reorientations over the past two decades, a situation...... which could be generally understood as the outcome of a series of interrelated political and economic factors shaping and re-shaping spatial planning in different European contexts. In Denmark, the effects of a recent structural reform that changed the geographies of inter-governmental arrangements...

  3. Interfering Waves of Adaptation Promote Spatial Mixing

    DEFF Research Database (Denmark)

    Martens, Erik Andreas; Hallatschek, Oskar

    2011-01-01

    to the evolution of sex and recombination in well-mixed populations. Here, we study clonal interference, and mechanisms of its mitigation, in an evolutionary model of spatially structured populations with uniform selection pressure. Clonal interference is much more prevalent with spatial structure than without...... for well-mixed populations (that scale as the logarithm of population size). Finally, we show that not only recombination, but also long-range migration is a highly efficient mechanism of relaxing clonal competition in structured populations. Our conservative estimates of the interference length predict...... prevalent clonal interference in microbial colonies and biofilms, so clonal competition should be a strong driver of both genetic and spatial mixing in those contexts....

  4. Scaling Laws in Spatial Network Formation

    CERN Document Server

    Molkenthin, Nora

    2016-01-01

    Geometric constraints impact the formation of a broad range of spatial networks, from amino acid chains folding to proteins structures to rearranging particle aggregates. How the network of interactions dynamically self-organizes in such systems is far from fully understood. Here, we analyze a class of spatial network formation processes by introducing a mapping from geometric to graph-theoretic constraints. Combining stochastic and mean field analyses yields an algebraic scaling law for the extent (graph diameter) of the resulting networks with system size, in contrast to logarithmic scaling known for networks without constraints. Intriguingly, the exponent falls between that of self-avoiding random walks and that of space filling arrangements, consistent with experimentally observed scaling (of the spatial radius of gyration) for protein tertiary structures.

  5. Employment effects of spatial dispersal of refugees

    DEFF Research Database (Denmark)

    Damm, Anna Piil; Rosholm, Michael

    2010-01-01

    Refugees subjected to a spatial dispersal tend to be assigned to a location outside the immigrant-dense cities. We argue that such locations are associated with low place utility. Our partial equilibrium search model with simultaneous job and residential location search predicts that the reservat......Refugees subjected to a spatial dispersal tend to be assigned to a location outside the immigrant-dense cities. We argue that such locations are associated with low place utility. Our partial equilibrium search model with simultaneous job and residential location search predicts...... that the reservation wage for local jobs decreases with place utility. We test the theoretical prediction by estimating the effects of characteristics of the location of assignment on the transition rate into the first job. Our sample is male refugees aged 30-59 who were subjected to the Danish spatial dispersal...

  6. Interfering Waves of Adaptation Promote Spatial Mixing

    DEFF Research Database (Denmark)

    Martens, Erik Andreas; Hallatschek, Oskar

    2011-01-01

    to the evolution of sex and recombination in well-mixed populations. Here, we study clonal interference, and mechanisms of its mitigation, in an evolutionary model of spatially structured populations with uniform selection pressure. Clonal interference is much more prevalent with spatial structure than without...... for well-mixed populations (that scale as the logarithm of population size). Finally, we show that not only recombination, but also long-range migration is a highly efficient mechanism of relaxing clonal competition in structured populations. Our conservative estimates of the interference length predict...... prevalent clonal interference in microbial colonies and biofilms, so clonal competition should be a strong driver of both genetic and spatial mixing in those contexts....

  7. Spatial Verification Using Wavelet Transforms: A Review

    CERN Document Server

    Weniger, Michael; Friederichs, Petra

    2016-01-01

    Due to the emergence of new high resolution numerical weather prediction (NWP) models and the availability of new or more reliable remote sensing data, the importance of efficient spatial verification techniques is growing. Wavelet transforms offer an effective framework to decompose spatial data into separate (and possibly orthogonal) scales and directions. Most wavelet based spatial verification techniques have been developed or refined in the last decade and concentrate on assessing forecast performance (i.e. forecast skill or forecast error) on distinct physical scales. Particularly during the last five years, a significant growth in meteorological applications could be observed. However, a comparison with other scientific fields such as feature detection, image fusion, texture analysis, or facial and biometric recognition, shows that there is still a considerable, currently unused potential to derive useful diagnostic information. In order to tab the full potential of wavelet analysis, we revise the stat...

  8. Spatial Modulation for MIMO Communication Systems

    Directory of Open Access Journals (Sweden)

    Reginaldo Nunes

    2012-11-01

    Full Text Available This work provides a review on the main spatial modulation (SM schemes, suitable to wireless communication systems. Performance, complexity and diversity gain of the three new spatial SM schemes suitable for multiple-input-multiple-output (MIMO communication systems are analyzed: a transmission scheme for spatial modulation (SM scheme; b space shift keying (SSK scheme; c generalized space shift keying (GSSK scheme. These three schemes offer low complexity, higher data rate when compared to single-input-single-output (SISO communication systems, as well as design flexibility, while exploits randomness characteristics of wireless communication channel for data transmission. The paper aims to explore the main features of those three SM schemes and to evaluate the inherent performance-complexity trade-off in order to determine which of those schemes results in a higher energy and spectral efficiencies.

  9. Spatial resolution in atom probe tomography

    CERN Document Server

    Gault, Baptiste; de Geuser, Frederic; La Fontaine, Alex; Stephenson, Leigh T; Haley, Daniel; Ringer, Simon P

    2015-01-01

    This article addresses gaps in definitions and a lack of standard measurement techniques to assess the spatial resolution in atom probe tomography. This resolution is known to be anisotropic, being better in the depth than laterally. Generally the presence of atomic planes in the tomographic reconstruction is considered as being a sufficient proof of the quality of the spatial resolution of the instrument. Based on advanced spatial distribution maps, an analysis methodology that interrogates the local neighborhood of the atoms within the tomographic reconstruction, it is shown how both the in-depth and the lateral resolution can be quantified. The influences of the crystallography and the temperature are investigated, and models are proposed to explain the observed results. We demonstrate that the absolute value of resolution is specimenspecific.

  10. Spatial Structures and Regulation in Biological Systems

    DEFF Research Database (Denmark)

    Yde, Pernille

    Spatial arrangements are very important for many biological systems. This thesis presents several different studies of biological systems, which are related to spatial arrangements at two different levels: one is the growth of biological macromolecules, here related to protein aggregation......, and the other is the spatial regulation of biological systems, here related to different aspects of the inflammatory response. All systems are studied using computational modelling and mathematical analysis. The first part of the thesis explores different protein aggregation scenarios. In Chapter 1, we consider...... an approximate analytical mathematical expression for the time evolution of the length distribution of the aggregate population, and we discuss the accuracy of the analytical expression. We also compare the model of frangible linear aggregation to experimentally obtained length distributions of growing insulin...

  11. Parametric methods for spatial point processes

    DEFF Research Database (Denmark)

    Møller, Jesper

    (This text is submitted for the volume ‘A Handbook of Spatial Statistics' edited by A.E. Gelfand, P. Diggle, M. Fuentes, and P. Guttorp, to be published by Chapmand and Hall/CRC Press, and planned to appear as Chapter 4.4 with the title ‘Parametric methods'.) 1 Introduction This chapter considers...... inference procedures for parametric spatial point process models. The widespread use of sensible but ad hoc methods based on summary statistics of the kind studied in Chapter 4.3 have through the last two decades been supplied by likelihood based methods for parametric spatial point process models....... The increasing development of such likelihood based methods, whether frequentist or Bayesian, has lead to more objective and efficient statistical procedures. When checking a fitted parametric point process model, summary statistics and residual analysis (Chapter 4.5) play an important role in combination...

  12. Quantum interference between transverse spatial waveguide modes

    Science.gov (United States)

    Mohanty, Aseema; Zhang, Mian; Dutt, Avik; Ramelow, Sven; Nussenzveig, Paulo; Lipson, Michal

    2017-01-01

    Integrated quantum optics has the potential to markedly reduce the footprint and resource requirements of quantum information processing systems, but its practical implementation demands broader utilization of the available degrees of freedom within the optical field. To date, integrated photonic quantum systems have primarily relied on path encoding. However, in the classical regime, the transverse spatial modes of a multi-mode waveguide have been easily manipulated using the waveguide geometry to densely encode information. Here, we demonstrate quantum interference between the transverse spatial modes within a single multi-mode waveguide using quantum circuit-building blocks. This work shows that spatial modes can be controlled to an unprecedented level and have the potential to enable practical and robust quantum information processing.

  13. Selectivity estimation using compressed spatial information

    Institute of Scientific and Technical Information of China (English)

    JEONG Jae-hyuck; CHI Jeong-hee; RYU Keun-ho

    2004-01-01

    Spatial selectivity estimation is one of the essential studies to get query responses rapidly and accurately with the limitation of memory space. Currently, there exist several spatial selectivity estimation techniques such as random sampling, histogram, and parametric. Especially, Cumulative Density Histogram guarantees accurate estimation for rectangle object which has multiple-count problem. However, it requires large memory space because of retaining four sub-histograms for spatial data. Therefore in this paper,we propose a new technique Cumulative Density Wavelet Histogram, called CDWH, which is the combination of Cumulative Density Histogram and Haar Wavelet Transform, a compressed technique. The proposed method simultaneously takes full advantage of their strong points, high accuracy provided by the former and economization of memory space supported by the latter. Consequently, our technique is able to support estimates with relatively low error and retain similar estimates even if memory space is small.

  14. Quantum interference between transverse spatial waveguide modes

    Science.gov (United States)

    Mohanty, Aseema; Zhang, Mian; Dutt, Avik; Ramelow, Sven; Nussenzveig, Paulo; Lipson, Michal

    2017-01-01

    Integrated quantum optics has the potential to markedly reduce the footprint and resource requirements of quantum information processing systems, but its practical implementation demands broader utilization of the available degrees of freedom within the optical field. To date, integrated photonic quantum systems have primarily relied on path encoding. However, in the classical regime, the transverse spatial modes of a multi-mode waveguide have been easily manipulated using the waveguide geometry to densely encode information. Here, we demonstrate quantum interference between the transverse spatial modes within a single multi-mode waveguide using quantum circuit-building blocks. This work shows that spatial modes can be controlled to an unprecedented level and have the potential to enable practical and robust quantum information processing. PMID:28106036

  15. Sustainable Development and Spatial Distribution of Industries

    Institute of Scientific and Technical Information of China (English)

    ShengYi

    2005-01-01

    At the cost of overdrawing from the environment, spatial distribution of industries takes promoting the economic growth as goal and makes the overload of industries coexist with the unreasonable arrangement in some areas, which is unable to satisfy the demand of sustainable development. To change the present development model, the spatial distribution of industries must coordinate with the environmental bearing capacity. The present practice we take to change resources distribution to meet the existing arrangement of industries will bring incredible calamitous consequence to the development in the future. To make industry's arrangement coordinate with ecological environment, and to adopt the method similar to “arranging along the rivers” should become the guidefines of spatial distribution of industries.

  16. Spatial Evolution of Openstreetmap Dataset in Turkey

    Science.gov (United States)

    Zia, M.; Seker, D. Z.; Cakir, Z.

    2016-10-01

    Large amount of research work has already been done regarding many aspects of OpenStreetMap (OSM) dataset in recent years for developed countries and major world cities. On the other hand, limited work is present in scientific literature for developing or underdeveloped ones, because of poor data coverage. In presented study it has been demonstrated how Turkey-OSM dataset has spatially evolved in an 8 year time span (2007-2015) throughout the country. It is observed that there is an east-west spatial biasedness in OSM features density across the country. Population density and literacy level are found to be the two main governing factors controlling this spatial trend. Future research paradigms may involve considering contributors involvement and commenting about dataset health.

  17. Spatial clustering with Density-Ordered tree

    Science.gov (United States)

    Cheng, Qing; Lu, Xin; Liu, Zhong; Huang, Jincai; Cheng, Guangquan

    2016-10-01

    Clustering has emerged as an active research direction for knowledge discovery in spatial databases. Most spatial clustering methods become ineffective when inappropriate parameters are given or when datasets of diverse shapes and densities are provided. To address this issue, we propose a novel clustering method, called SCDOT (Spatial Clustering with Density-Ordered Tree). By projecting a dataset to a Density-Ordered Tree, SCDOT partitions the data into several relatively small sub-clusters with a box-plot method. A heuristic method is proposed to find the genuine clusters by repeatedly merging sub-clusters and an iteration strategy is utilized to automatically determine input parameters. Moreover, we also provide an innovative way to identify cluster center and noise. Extensive experiments on both synthetic and real-world datasets demonstrate the superior performance of SCDOT over the baseline methods.

  18. Spatially explicit non-Mendelian diploid model

    CERN Document Server

    Lanchier, N; 10.1214/09-AAP598

    2009-01-01

    We introduce a spatially explicit model for the competition between type $a$ and type $b$ alleles. Each vertex of the $d$-dimensional integer lattice is occupied by a diploid individual, which is in one of three possible states or genotypes: $aa$, $ab$ or $bb$. We are interested in the long-term behavior of the gene frequencies when Mendel's law of segregation does not hold. This results in a voter type model depending on four parameters; each of these parameters measures the strength of competition between genes during meiosis. We prove that with or without a spatial structure, type $a$ and type $b$ alleles coexist at equilibrium when homozygotes are poor competitors. The inclusion of a spatial structure, however, reduces the parameter region where coexistence occurs.

  19. Spatial Dynamics of Indoor Radio Wideband Channels

    Directory of Open Access Journals (Sweden)

    Hayar Aawatif

    2010-01-01

    Full Text Available The multipath components of superwideband (2–17.2 GHz nonline-of-sight channel responses measured inside several buildings are stable along sections that are 27 cm long on average with a standard deviation of 16 cm. The stability regions of multipath components have an approximately log-normal histogram. An analysis of measured channels that explicitly includes finite spatial areas of visibility of the multipath components is superior to the classic analysis that attributes spatial dynamics to interference of the multipath. The spatial stability of measured responses, that is, the size of the typical area of visibility of each multipath component, decreases as the carrier frequency increases but does not depend on bandwidth. The results offer insight into the nature of the diffuse part of the radio channel.

  20. GIS as spatial decision support system

    Directory of Open Access Journals (Sweden)

    V. Vostrovský

    2011-06-01

    Full Text Available This paper describes the possibility of the Geographic Information Systems (GIS as a means to support decision making in solving spatial problems. Spatial problems accompany every human activity, of which agriculture is no exception. The solutions to these problems requires the application of available knowledge in the relevant decision-making processes. GISs integrate hardware, software, and data for capturing, managing, analyzing, and displaying all forms of geographically referenced information. Coupled with GISs, geography helps to better understand and apply geographic knowledge to a host of global problems (unemployment, environmental pollution, the loss of arable land, epidemics etc.. The result may be a geographical approach represents a new way of thinking and solutions to existing spatial problems. This approach allows to apply existing knowledge to model and analyze these problems and thus help to solve them.

  1. Videogame interventions and spatial ability interactions

    Directory of Open Access Journals (Sweden)

    Thomas S. Redick

    2014-03-01

    Full Text Available Numerous research studies have been conducted on the use of videogames as tools to improve one’s cognitive abilities. While meta-analyses and qualitative reviews have provided evidence that some aspects of cognition such as spatial imagery are modified after exposure to videogames, other evidence has shown that matrix reasoning measures of fluid intelligence do not show evidence of transfer from videogame training. In the current work, we investigate the available evidence for transfer specifically to nonverbal intelligence and spatial ability measures, given recent research that these abilities may be most sensitive to training on cognitive and working memory tasks. Accordingly, we highlight a few studies that on the surface provide evidence for transfer to spatial abilities, but a closer look at the pattern of data does not reveal a clean interpretation of the results. We discuss the implications of these results in relation to research design and statistical analysis practices.

  2. Spatially-Coupled Random Access on Graphs

    CERN Document Server

    Liva, Gianluigi; Lentmaier, Michael; Chiani, Marco

    2012-01-01

    In this paper we investigate the effect of spatial coupling applied to the recently-proposed coded slotted ALOHA (CSA) random access protocol. Thanks to the bridge between the graphical model describing the iterative interference cancelation process of CSA over the random access frame and the erasure recovery process of low-density parity-check (LDPC) codes over the binary erasure channel (BEC), we propose an access protocol which is inspired by the convolutional LDPC code construction. The proposed protocol exploits the terminations of its graphical model to achieve the spatial coupling effect, attaining performance close to the theoretical limits of CSA. As for the convolutional LDPC code case, large iterative decoding thresholds are obtained by simply increasing the density of the graph. We show that the threshold saturation effect takes place by defining a suitable counterpart of the maximum-a-posteriori decoding threshold of spatially-coupled LDPC code ensembles. In the asymptotic setting, the proposed s...

  3. Emergent universe in spatially flat cosmological model

    CERN Document Server

    Zhang, Kaituo; Yu, Hongwei

    2013-01-01

    The scenario of an emergent universe provides a promising resolution to the big bang singularity in universes with positive or negative spatial curvature. It however remains unclear whether the scenario can be successfully implemented in a spatially flat universe which seems to be favored by present cosmological observations. In this paper, we study the stability of Einstein static state solutions in a spatially flat Shtanov-Sahni braneworld scenario. With a negative dark radiation term included and assuming a scalar field as the only matter energy component, we find that the universe can stay at an Einstein static state past eternally and then evolve to an inflation phase naturally as the scalar field climbs up its potential slowly. In addition, we also propose a concrete potential of the scalar field that realizes this scenario.

  4. Analysis of a spatially deconvolved solar pore

    CERN Document Server

    Noda, C Quintero; Cobo, B Ruiz; Suematsu, Y; Katsukawa, Y; Ichimoto, K

    2016-01-01

    Solar pores are active regions with large magnetic field strengths and apparent simple magnetic configurations. Their properties resemble the ones found for the sunspot umbra although pores do not show penumbra. Therefore, solar pores present themselves as an intriguing phenomenon that is not completely understood. We examine in this work a solar pore observed with Hinode/SP using two state of the art techniques. The first one is the spatial deconvolution of the spectropolarimetric data that allows removing the stray light contamination induced by the spatial point spread function of the telescope. The second one is the inversion of the Stokes profiles assuming local thermodynamic equilibrium that let us to infer the atmospheric physical parameters. After applying these techniques, we found that the spatial deconvolution method does not introduce artefacts, even at the edges of the magnetic structure, where large horizontal gradients are detected on the atmospheric parameters. Moreover, we also describe the p...

  5. Spatial distribution maps for benthic communities

    DEFF Research Database (Denmark)

    Sørensen, Per S.

    1999-01-01

    simulation, Markov random fields and Boolean models. Geostatistical simulation provides a means of assessing the variability of random field functionals such as the estimated distribution area of a benthic species. The Markov random field allows the spatial distribution of the benthic communities......The application of hydroacoustic measurements for preparation of spatial distribution maps of benthic communities is reported. For the present study common mussels (Mytilus edulis), neptune grass (Posidonia oceanica) and Cymodocea nodosa, serving as canonical species of many European marine....... The estimates of variability obtained for estimated distribution areas with the two approaches compare satisfactorily. The Boolean models are suggested as a point of departure for embedding models of spatial patterns on the minor scales of observations to be used in up-scaling approaches to enhance the quality...

  6. Extrapolating spatial layout in scene representations.

    Science.gov (United States)

    Castelhano, Monica S; Pollatsek, Alexander

    2010-12-01

    Can the visual system extrapolate spatial layout of a scene to new viewpoints after a single view? In the present study, we examined this question by investigating the priming of spatial layout across depth rotations of the same scene (Sanocki & Epstein, 1997). Participants had to indicate which of two dots superimposed on objects in the target scene appeared closer to them in space. There was as much priming from a prime with a viewpoint that was 10° different from the test image as from a prime that was identical to the target; however, there was no reliable priming from larger differences in viewpoint. These results suggest that a scene's spatial layout can be extrapolated, but only to a limited extent.

  7. Spatially Partitioned Embedded Runge--Kutta Methods

    KAUST Repository

    Ketcheson, David I.

    2013-10-30

    We study spatially partitioned embedded Runge--Kutta (SPERK) schemes for partial differential equations (PDEs), in which each of the component schemes is applied over a different part of the spatial domain. Such methods may be convenient for problems in which the smoothness of the solution or the magnitudes of the PDE coefficients vary strongly in space. We focus on embedded partitioned methods as they offer greater efficiency and avoid the order reduction that may occur in nonembedded schemes. We demonstrate that the lack of conservation in partitioned schemes can lead to nonphysical effects and propose conservative additive schemes based on partitioning the fluxes rather than the ordinary differential equations. A variety of SPERK schemes are presented, including an embedded pair suitable for the time evolution of fifth-order weighted nonoscillatory spatial discretizations. Numerical experiments are provided to support the theory.

  8. Standing variation in spatially growing populations

    Science.gov (United States)

    Fusco, Diana; Gralka, Matti; Kayser, Jona; Hallatschek, Oskar

    Patterns of genetic diversity not only reflect the evolutionary history of a species but they can also determine the evolutionary response to environmental change. For instance, the standing genetic diversity of a microbial population can be key to rescue in the face of an antibiotic attack. While genetic diversity is in general shaped by both demography and evolution, very little is understood when both factors matter, as e.g. for biofilms with pronounced spatial organization. Here, we quantitatively explore patterns of genetic diversity by using microbial colonies and well-mixed test tube populations as antipodal model systems with extreme and very little spatial structure, respectively. We find that Eden model simulations and KPZ theory can remarkably reproduce the genetic diversity in microbial colonies obtained via population sequencing. The excellent agreement allows to draw conclusions on the resilience of spatially-organized populations and to uncover new strategies to contain antibiotic resistance.

  9. Spatial determinants of poverty in rural Kenya.

    Science.gov (United States)

    Okwi, Paul O; Ndeng'e, Godfrey; Kristjanson, Patti; Arunga, Mike; Notenbaert, An; Omolo, Abisalom; Henninger, Norbert; Benson, Todd; Kariuki, Patrick; Owuor, John

    2007-10-23

    This article investigates the link between poverty incidence and geographical conditions within rural locations in Kenya. Evidence from poverty maps for Kenya and other developing countries suggests that poverty and income distribution are not homogenous. We use spatial regression techniques to explore the effects of geographic factors on poverty. Slope, soil type, distance/travel time to public resources, elevation, type of land use, and demographic variables prove to be significant in explaining spatial patterns of poverty. However, differential influence of these and other factors at the location level shows that provinces in Kenya are highly heterogeneous; hence different spatial factors are important in explaining welfare levels in different areas within provinces, suggesting that targeted propoor policies are needed. Policy simulations are conducted to explore the impact of various interventions on location-level poverty levels. Investments in roads and improvements in soil fertility are shown to potentially reduce poverty rates, with differential impacts in different regions.

  10. Panel data models extended to spatial error autocorrelation or a spatially lagged dependent variable

    NARCIS (Netherlands)

    Elhorst, J. Paul

    2001-01-01

    This paper surveys panel data models extended to spatial error autocorrelation or a spatially lagged dependent variable. In particular, it focuses on the specification and estimation of four panel data models commonly used in applied research: the fixed effects model, the random effects model, the

  11. Self-locomotion and spatial language and spatial cognition: Insights from typical and atypical development

    NARCIS (Netherlands)

    Oudgenoeg - Paz, Ora; Riviére, James

    2014-01-01

    Various studies have shown that occurrence of locomotion in infancy is correlated with the development of spatial cognitive competencies. Recent evidence suggests that locomotor experience might also be important for the development of spatial language. Together these findings suggest that locomotor

  12. Can infant self-locomotion and spatial exploration predict spatial memory at school age?

    NARCIS (Netherlands)

    Oudgenoeg-Paz, Ora; Leseman, Paul P M; Volman, M.J.M.

    2014-01-01

    According to an embodied view of development sensorimotor activity plays a central role in cognitive development. Following this idea, we studied whether the age of achieving self-locomotion milestones and spatial exploration during the first years of life predict spatial memory at (pre)school age.

  13. Spatially Periodic System with Infinite Globally Coupled Oscillators Driven by Temporal-Spatial Noise

    Institute of Scientific and Technical Information of China (English)

    HAN Yin-Xia; LI Jing-Hui; ZHAO Ying-Kui; CHEN Shi-Gang

    2005-01-01

    In this paper, we study spatially periodic system with infinite globally coupled oscillators driven by temporal-spatial noise and subject to a constant force. The results show that the system exhibits the phenomena of the non-equilibrium phase transition, transport of particles, and the anomalous hysteresis cycle for the mean field and the probability current.

  14. Spatial-Sequential and Spatial-Simultaneous Working Memory in Individuals with Williams Syndrome

    Science.gov (United States)

    Lanfranchi, Silvia; De Mori, Letizia; Mammarella, Irene C.; Carretti, Barbara; Vianello, Renzo

    2015-01-01

    The aim of the present study was to compare visuospatial working memory performance in 18 individuals with Williams syndrome (WS) and 18 typically developing (TD) children matched for nonverbal mental age. Two aspects were considered: task presentation format (i.e., spatial-sequential or spatial-simultaneous), and level of attentional control…

  15. Early Development of Spatial-Numeric Associations: Evidence from Spatial and Quantitative Performance of Preschoolers

    Science.gov (United States)

    Opfer, John E.; Thompson, Clarissa A.; Furlong, Ellen E.

    2010-01-01

    Numeric magnitudes often bias adults' spatial performance. Partly because the direction of this bias (left-to-right versus right-to-left) is culture-specific, it has been assumed that the orientation of spatial-numeric associations is a late development, tied to reading practice or schooling. Challenging this assumption, we found that preschoolers…

  16. The Spatial and the Visual in Mental Spatial Reasoning: An Ill-Posed Distinction

    Science.gov (United States)

    Schultheis, Holger; Bertel, Sven; Barkowsky, Thomas; Seifert, Inessa

    It is an ongoing and controversial debate in cognitive science which aspects of knowledge humans process visually and which ones they process spatially. Similarly, artificial intelligence (AI) and cognitive science research, in building computational cognitive systems, tended to use strictly spatial or strictly visual representations. The resulting systems, however, were suboptimal both with respect to computational efficiency and cognitive plau sibility. In this paper, we propose that the problems in both research strands stem from a mis conception of the visual and the spatial in mental spatial knowl edge pro cessing. Instead of viewing the visual and the spatial as two clearly separable categories, they should be conceptualized as the extremes of a con tinuous dimension of representation. Regarding psychology, a continuous di mension avoids the need to exclusively assign processes and representations to either one of the cate gories and, thus, facilitates a more unambiguous rating of processes and rep resentations. Regarding AI and cognitive science, the con cept of a continuous spatial / visual dimension provides the possibility of rep re sentation structures which can vary continuously along the spatial / visual di mension. As a first step in exploiting these potential advantages of the pro posed conception we (a) introduce criteria allowing for a non-dichotomic judgment of processes and representations and (b) present an approach towards rep re sentation structures that can flexibly vary along the spatial / visual dimension.

  17. The accuracy of spatial information from temporally and spatially organized mental maps.

    Science.gov (United States)

    Curiel, Jacqueline M; Radvansky, Gabriel A

    2004-04-01

    The way a space is learned can result in a mental map that is either temporally or spatially organized (Curiel & Radvansky, 1998). The present study examined the availability of spatial information under map learning conditions where either temporal or spatial organization has been previously observed. The finding was that people were fairly accurate in tasks that explicitly required the use of spatial information. However, there was a particular advantage for having a spatially organized mental map in a direction judgment task, especially for short distances where fine-grained knowledge was required. In contrast, there was no clear advantage for either group in a distance estimation task. These data are interpreted in the context of Huttenlocher's category adjustment model.

  18. MGlu5 antagonism impairs exploration and memory of spatial and non-spatial stimuli in rats

    DEFF Research Database (Denmark)

    Christoffersen, Gert Rene Juul; Simonyi, Agnes; Schachtman, Todd R.;

    2008-01-01

    ) long-term retention of spatial conditioning in the cross-maze was inhibited after i.p. applications which 4) also inhibited spontaneous alternation performance during maze-exploration. Reduced exploratory locomotion and exploration time after i.p. injections may have contributed to the observed...... and it was found that: 1) Locomotion during exploration of spatial environments and exploration time at novel objects were reduced by i.p. but not by prelimbic administration of MPEP, 2) spatial short-term memory was impaired in cross-maze and object discrimination was reduced after both types of administration, 3...... retention impairments. However, the fact that prelimbic administration of MPEP inhibited retention without reducing exploration shows that memory formation was also impacted directly by prelimbic mGlu5 in both spatial and non-spatial learning....

  19. Marine spatial planning and Good Environmental Status: a perspective on spatial and temporal dimensions

    Directory of Open Access Journals (Sweden)

    Alison J. Gilbert

    2015-03-01

    Full Text Available The European Union Marine Strategy Framework Directive requires the Good Environmental Status of marine environments in Europe's regional seas; yet, maritime activities, including sources of marine degradation, are diversifying and intensifying in an increasingly globalized world. Marine spatial planning is emerging as a tool for rationalizing competing uses of the marine environment while guarding its quality. A directive guiding the development of such plans by European Union member states is currently being formulated. There is an undeniable need for marine spatial planning. However, we argue that considerable care must be taken with marine spatial planning, as the spatial and temporal scales of maritime activities and of Good Environmental Status may be mismatched. We identify four principles for careful and explicit consideration to align the requirements of the two directives and enable marine spatial planning to support the achievement of Good Environmental Status in Europe's regional seas.

  20. Recent developments in spatial analysis spatial statistics, behavioural modelling, and computational intelligence

    CERN Document Server

    Getis, Arthur

    1997-01-01

    In recent years, spatial analysis has become an increasingly active field, as evidenced by the establishment of educational and research programs at many universities. Its popularity is due mainly to new technologies and the development of spatial data infrastructures. This book illustrates some recent developments in spatial analysis, behavioural modelling, and computational intelligence. World renown spatial analysts explain and demonstrate their new and insightful models and methods. The applications are in areas of societal interest such as the spread of infectious diseases, migration behaviour, and retail and agricultural location strategies. In addition, there is emphasis on the uses of new technologoies for the analysis of spatial data through the application of neural network concepts.