A probabilistic framework for improving reverse geocoding output     

Zhengcong Yin  Daniel W. Goldberg  Tracy A. Hammond  Chong Zhang  Andong Ma  Xiao Li 《Transactions in GIS》2020,24(3):656-680

Reverse geocoding, which transforms machine‐readable GPS coordinates into human‐readable location information, is widely used in a variety of location‐based services and analysis. The output quality of reverse geocoding is critical because it can greatly impact these services provided to end‐users. We argue that the output of reverse geocoding should be spatially close to and topologically correct with respect to the input coordinates, contain multiple suggestions ranked by a uniform standard, and incorporate GPS uncertainties. However, existing reverse geocoding systems often fail to fulfill these aims. To further improve the reverse geocoding process, we propose a probabilistic framework that includes: (1) a new workflow that can adapt all existing address models and unitizes distance and topology relations among retrieved reference data for candidate selections; (2) an advanced scoring mechanism that quantifies characteristics of the entire workflow and orders candidates according to their likelihood of being the best candidate; and (3) a novel algorithm that derives statistical surfaces for input GPS uncertainties and propagates such uncertainties into final output lists. The efficiency of the proposed approaches is demonstrated through comparisons to the four commercial reverse geocoding systems and through human judgments. We envision that more advanced reverse geocoding output ranking algorithms specific to different application scenarios can be built upon this work.  相似文献   

A comparison of network model creation algorithms based on the quality of wayfinding results     

Jinwoo Park  Daniel W. Goldberg  Tracy Hammond 《Transactions in GIS》2020,24(3):602-622

Various network model creation algorithms have been introduced to demonstrate a better approximation of the actual walking pattern and to provide a better wayfinding guide. However, it is under‐investigated which algorithm creates the most appropriate indoor navigation network model in the context of wayfinding applications. Due to the lack of discussion, some studies unconsciously extended an algorithm designed for creating an outdoor navigation network model to indoor space applications. This is problematic because indoor space has different spatial contexts from outdoor space, such as non‐linear space and no‐designated walking space. Our solution is to select five well‐known algorithms that have been introduced, to reproduce the algorithm for the automated construction of the indoor navigation network model, and to evaluate the applicability of algorithms for indoor wayfinding applications. This article compares the quality of wayfinding results from the output of the indoor navigation network model against two criteria: route efficiency (i.e., length) and route simplicity (i.e., number of directions). Our statistical analysis illustrates that the visibility graph algorithm is the most appropriate for indoor wayfinding applications.  相似文献   

The characteristic pattern of multiple colored layers in coastal stratified lakes in the process of separation from the White Sea   总被引：1，自引：1，他引：0  

Krasnova  Elena D.  Matorin  Dmitry N.  Belevich  Tatiana A.  Efimova  Ludmila E.  Kharcheva  Anastasiia V.  Kokryatskaya  Natalia M.  Losyuk  Galina N.  Todorenko  Daria A.  Voronov  Dmitry A.  Patsaeva  Svetlana V. 《中国海洋湖沼学报》2018,36(6):1962-1977

An unusual feature of the saline stratified lakes that were formed due to ongoing postglacial uplift on the White Sea coast is the presence of several differently colored thin layers in the zone with sharp gradients. Colored layers in five lakes at various stages of separation from the sea were investigated using optical microscopy, spectrophotometry, spectrofluorimetry, and photobiology. The upper greenish colored layer located in the aerobic strata of all lakes near the compensation depth of 1% light penetration contains green algae. In the chemocline, another layer, brightly green, red or pink, is dominated by mixotrophic flagellates. Despite the very low light intensities and the presence of H 2 S, active photosynthesis by these algae appears to be occurring, as indicated by high values of the maximum quantum yield of primary photochemistry, electron transport activity, photosynthetic activity of photosystem II, the fraction of active centers, and low values of heat dissipation. In the reduced zone of the chemocline, a dense green or brown suspension of anoxygenic phototrophs(green sulfur bacteria) is located.  相似文献   

Scales of predator detection behavior and escape in Fissurella limbata: A field and laboratory assessment          下载免费PDF全文

Tatiana Manzur  Avia Gonzalez‐Mendez  Bernardo R. Broitman 《Marine Ecology》2018,39(2)

The consumptive effects of predators are widely acknowledged, but predation can also impact prey populations through non‐consumptive effects (NCEs) such as costly antipredator behavioral responses. The magnitude of antipredator behavioral responses by prey is determined by an assessment of risk using sensory cues, which in turn is modulated by the environmental context. We studied the detection behavior and escape response of the keyhole limpet Fissurella limbata from the predatory sea star Heliaster helianthus. Through laboratory and field experimental trials, we quantified the distance and time of predator detection behavior by the prey, and measured their active escape responses when elicited. We found that predator detection by the limpet was chiefly mediated by distance, with experimental individuals capable of detecting predator presence effectively up to distances of at least 50 cm in the field and 70 cm under laboratory conditions. Our results indicate that this prey species is able to evaluate the proximity of its predator and use it as an indication of predation risk; therefore, predator–prey distance appears to be a primary predictor of the magnitude of the antipredator response. Given the tight relationship between predator distance and prey movement and the important role herbivores can play, particularly in this ecosystem, we expect that NCEs will cascade to the patterns of abundance and composition of rocky shore communities through changes in prey foraging behavior under risk.  相似文献   

Stabilization versus decomposition in alpine ecosystems of the Northwestern Caucasus: The results of a tea bag burial experiment     

Tatiana G. Elumeeva  Vladimir G. Onipchenko  Asem A. Akhmetzhanova  Mikhail I. Makarov  Joost A. Keuskamp 《山地科学学报》2018,15(8):1633-1641

Mountainous areas exhibit highly variable decomposition rates as a result of strong local differences in climate and vegetation type. This paper describes the effect of these factors on two major determinants of the local carbon cycle: litter decomposition and carbon stabilization. In order to adequately reflect local heterogeneity, we have sampled 12 typical plant communities of the Russian Caucasus. In order to minimize confounding effects and encourage comparative studies, we have adapted the widely used tea bag index (TBI) that is typically used in areas with low decomposition. By incubating standardized tea litter for a year, we investigated whether (1) initial litter decomposition rate (k) is negatively correlated with litter stabilization (S) and (2) whether k or S exhibit correlations with altitude and other environmental conditions. Our results show that S and k are not correlated. Altitude, pH, and water content significantly influenced the stabilization factor S, while soil-freezing had no influence. In contrast, none of these factors predicted the decomposition rate k. Based on our data, we argue that collection of decomposition rates alone, as is now common practice, is not sufficient to understand carbon input to soils and can potentially lead to misleading results. Our data on community-specific decomposition and stabilization rates further constrain estimates of litter accumulation in subalpine communities and the potential effects of climate change.  相似文献   

Effects of long-term medieval agriculture on soil properties: A case study from the Kislovodsk basin,Northern Caucasus,Russia     

Elena Chernysheva  Tatiana Khomutova  Flavio Fornasier  Tatiana Kuznetsova  Alexandr Borisov 《山地科学学报》2018,15(6):1171-1185

The chemical properties and biological activities of soils were studied in the vicinity of the medieval settlement Podkumskoe-3 in the Kislovodsk basin (Northern Caucasus, Russia). Between the 5th and 8th centuries this area was ploughed regularly, but it was then abandoned up to the present day. It has been established that past human activity leads to soil undergoing significant transformations in terms of microbial communities and enzyme activity, and that such changes are maintained over long periods. Long-term manuring in the middle of the first millennium AD led to an increase in organic carbon content and the accumulation of nitrate nitrogen. Soils of ancient abandoned fields are associated with increases in microbial biomass, number of saprotrophic bacteria, urease activity, and fungal mycelium biomass. The observed changes in the microbiological and biochemical properties of soil were conditioned by secondary anthropogenically induced succession after the abandonment of arable lands.  相似文献   

Broadband seismic source data acquisition and processing to delineate iron oxide deposits in the Blötberget mine-central Sweden     

Tatiana Pertuz  Alireza Malehmir  Jordan Bos  Bojan Brodic  Yinshuai Ding  Richard de Kunder  Paul Marsden 《Geophysical Prospecting》2022,70(1):79-94

A prototype electromagnetic vibrator, referred to here as E-Vib, was upgraded and developed for broadband hardrock and mineral exploration seismic surveys. We selected the iron oxide mine in Blötberget, central Sweden, for a test site in 2019 for the newly developed E-Vib because of the availability of earlier seismic datasets (from 2015 to 2016) for verification of its performance for hardrock imaging purposes. The two-dimensional data acquisition consisted of a fixed geometry with 550 receiver locations spaced at every 5 m, employing both cabled and wireless seismic recorders, along an approximately 2.7 km long profile. The E-Vib operated at every second receiver station (i.e. 10 m spacing) with a linear sweep of 2–180 Hz and with a peak force of 7 kN. The processing workflow took advantage of the broadband signal generated by the E-Vib in this challenging hardrock environment with varying ground conditions. The processed seismic section shows a set of reflections associated with the known iron oxide mineralization and a major crosscutting reflection interpreted to be from a fault system likely to be crosscutting the mineralization. The broadband source data acquisition and subsequent processing helped to improve signal quality and resolution in comparison with the earlier workflows and data where a drophammer seismic source was used as the seismic source. These results suggest new possibilities for the E-Vib source for improved targeting in hardrock geological settings.  相似文献   

The limit passage of space curvature in problems of celestial mechanics with the generalized Kepler and Hooke potentials     

Tatiana Vozmishcheva 《Astrophysics and Space Science》2016,361(9):282

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Throughfall patterns in sugarcane and riparian forest: understanding the effect of sugarcane age and land use conversion          下载免费PDF全文

Robson Willians da Costa Silva  Luiz Felippe Salemi  Rafael Pires Fernandes  Tatiana Morgan Berteli de Andrade  Jorge Marcos de Moraes  Plínio Barbosa de Camargo  Luiz Antonio Martinelli 《水文研究》2016,30(15):2579-2589

Sugarcane is an annual crop with a dynamic canopy that changes over time mainly because of genetic adaptation. There is uncertainty about the temporal trends of throughfall (TF) in this important commercial crop. In the present paper, we used troughs to measure TF in a third and fourth ratoon and subsequently in a fourth and fifth ratoon. Additional measurements were carried out in an adjacent riparian forest. There were no significant differences between cycles of sugarcane, growth phases and riparian forest. The TF results for ratoon crop and riparian forest in 2011/2012 were 76% and 79.5% of gross rainfall, respectively, while in 2012/2013, they were 79% and 78%, respectively. However, TF was remarkably lower in the riparian forest relative to ratoon from the second half of the culm formation and elongation phase (280 days after harvest) until harvest. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

Thermodynamic characterization of boltwoodite and uranophane: Enthalpy of formation and aqueous solubility     

Tatiana Y. Shvareva  Drew Gorman-Lewis  Peter C. Burns  Jeremy B. Fein 《Geochimica et cosmochimica acta》2011,75(18):5269-5282

Boltwoodite and uranophane are uranyl silicates common in oxidized zones of uranium ore deposits. An understanding of processes that impact uranium transport in the environment, especially pertaining to the distribution of uranium between solid phases and aqueous solutions, ultimately requires determination of thermodynamic parameters for such crystalline materials. We measured formation enthalpies of synthetic boltwoodites, K(UO₂)(HSiO₄)·H₂O and Na(UO₂)(HSiO₄)·H₂O, and uranophane, Ca(UO₂)₂(HSiO₄)₂·5H₂O, by high temperature oxide melt solution calorimetry. We also studied the aqueous solubility of these phases from both saturated and undersaturated conditions at a variety of pH. The combined data permit the determination of standard enthalpies, entropies and Gibbs free energies of formation for each phase and analysis of its potential geological impact from a thermodynamic point of view.  相似文献