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Статті в журналах з теми "Spatio-temporal Durbin model"
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Croonenbroeck, Carsten, and Marcel Palm. "A spatio-temporal Durbin fixed effects IV-Model for ENTSO-E electricity flows analysis." Renewable Energy 148 (April 2020): 205–13. http://dx.doi.org/10.1016/j.renene.2019.11.133.
Повний текст джерела
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Hawkins, Jason, and Khandker Nurul Habib. "Spatio-Temporal Hedonic Price Model to Investigate the Dynamics of Housing Prices in Contexts of Urban Form and Transportation Services in Toronto." Transportation Research Record: Journal of the Transportation Research Board 2672, no. 6 (June 8, 2018): 21–30. http://dx.doi.org/10.1177/0361198118774153.
Повний текст джерелаАнотація:
A spatio-temporal hedonic price model is developed for the Greater Toronto area to examine the effects of urban configurations and proximity to transit services on housing price. A spatial Durbin panel model is utilized to account for both spatial and temporal autocorrelation. This model is shown to have advantages through its ability to reduce the number of explanatory variables required to obtain a strong fit with empirical data. Analysis is completed for the period of 1996 to 2017 and distinctions are made in housing stock between single-family houses, townhouses, and condominiums. It is shown that heterogeneities exist between the hedonic representations of each dwelling type and that separate models should be employed for each. In all cases, the average income of the community, its distance to the central business district (CBD), and population and employment density are found to be significant factors in the determination of price.
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Xu, Zhen, Xiang Zhu, Guoen Wei, and Xiao Ouyang. "Spatio-Temporal Evolution and Mechanism Analysis of China’s Regional Innovation Efficiency." Sustainability 13, no. 19 (October 7, 2021): 11089. http://dx.doi.org/10.3390/su131911089.
Повний текст джерелаАнотація:
Improving regional innovation efficiency is the key to developing an innovative country. Exploring the spatio-temporal evolution characteristics of regional innovation efficiency is crucial in the formulation of regional policies and the choice of innovation models. This study used the superdata envelopment analysis method with undesirable outputs in evaluating the innovation efficiency of Chinese provinces. To assess the spatial spillover effects of innovation factors, the spatial autocorrelation and spatial Durbin model were adopted to characterize the spatio-temporal evolution, spatial correlation, and mechanisms of innovation efficiency. The highlights of the results are as follows: (1) The time-series changes in innovation efficiency showed a general trend from declining to increasing. (2) There were pronounced regional differences in innovation efficiency. The innovation efficiencies at the provincial level evolved from being decentralized to concentrated. The innovation efficiency was relatively stable in the eastern region and increased significantly in the central and western regions. The east–center–west evolution pattern gradually weakened. (3) The innovative efficiency exhibited spatial dependence, and the spatial agglomeration continued to increase. The extent of hot spots expanded, while cold spots shrunk slightly. (4) The scientific research environment, entrepreneurial environment, labor quality, and market environment were the essential elements that improved innovation efficiency. The impact of the different factors on innovation efficiency at different periods exhibited significant spatial heterogeneity.
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Su, Hao, and Shuo Yang. "Spatio-Temporal Urban Land Green Use Efficiency under Carbon Emission Constraints in the Yellow River Basin, China." International Journal of Environmental Research and Public Health 19, no. 19 (October 4, 2022): 12700. http://dx.doi.org/10.3390/ijerph191912700.
Повний текст джерелаАнотація:
In the context of rapid urbanization and limited land amount, it is essential to scientifically evaluate the urban land green use efficiency (ULGUE) to promote regional sustainable development. Current studies are of great value for enriching the theoretical system and application research of ULGUE. Still, most of them only consider industrial pollution but ignore carbon emission as an essential environmental influencing indicator. This paper introduced carbon emissions into the input-output indicator system, measured ULGUE of 57 cities in the Yellow River Basin (YRB) over the 2004–2017 periods using the super-efficiency slacked-based measure (Super-SBM) model, analyzed its spatio-temporal patterns with the kernel density estimation (KDE) model and spatial autocorrelation model, and then identified the influencing factors with the Spatial Durbin model (SDM). As shown by the results, firstly, the ULGUE in the YRB over the 2004–2017 periods showed a trend of first decreasing and then increasing. Secondly, the ULGUE exhibited spatio-temporal imbalance characteristics across the YRB. Thirdly, ULGUE was the interaction of multiple indicators, and its influencing factors had spatial spillover effects. All in all, this paper is fundamental to the high-quality development of cities in the background of the Chinese policy of “carbon peak, carbon neutralization”.
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Ma, Debin, Jie Zhang, Ziyi Wang, and Dongqi Sun. "Spatio-Temporal Evolution and Influencing Factors of Open Economy Development in the Yangtze River Delta Area." Land 11, no. 10 (October 16, 2022): 1813. http://dx.doi.org/10.3390/land11101813.
Повний текст джерелаАнотація:
Since economic globalization is unstable, it is difficult for the traditional open economic development model to meet the requirements of China’s development, and there is an urgent need for new ideas and models to be reoriented. Based on the analysis of the development mechanism of China’s open economy at this stage, we used the entropy method, Theil coefficient, Gini coefficient, and spatial Durbin model (SDM) to analyze the spatio-temporal pattern and influencing factors of the high-quality development level of the open economy in the Yangtze River Delta Area (YRDA). The results indicated that during the study period, the development level and development difference of open economy were on the rise, and the spatial difference in different regions was significant. The development of open economy was affected by many factors, and there was a spatial spillover effect. Based on the existing problems, at the stage of high-quality economic development, the YDRA should seize the opportunities brought by the new development pattern, improve government services, optimize innovation drive, and promote the development of open economy to a higher level. We believe that the results of this study can also provide relevant experience for the development of open economy in other regions of China.
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Zhuang, Rulong, Kena Mi, and Zhangwei Feng. "Industrial Co-Agglomeration and Air Pollution Reduction: An Empirical Evidence Based on Provincial Panel Data." International Journal of Environmental Research and Public Health 18, no. 22 (November 18, 2021): 12097. http://dx.doi.org/10.3390/ijerph182212097.
Повний текст джерелаАнотація:
Industrial co-agglomeration plays a significant role in the moving up of the manufacturing industry in the value chain and in transforming China from a manufacturing giant into a world manufacturing power. This study establishes a co-aggregation index to explore spatio-temporal changes of the co-agglomeration between manufacturing and producer services in 30 provinces of China from 2004 to 2019. Furthermore, we use spatial Durbin model to analyze the impact of industrial co-agglomeration on air pollution reduction. We find that (1) the co-agglomeration index varies remarkably at spatio-temporal scale; (2) high co-agglomeration index is mainly distributed in eastern and central China, while low co-agglomeration index is mainly located in the western region; (3) the co-agglomeration index presents a cluster pattern among provinces, with the cluster of high value in eastern China and the cluster of low value in western China; and (4) the co-agglomeration between manufacturing and producer services is proven effetely to reduce air pollution, which is accompanied with spatial spillover effect. We also provided policy implications in line with diverse industries, multi hierarchies, and different regions, promoting the coordination of manufacturing and producer services and improving air quality.
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Vallés-Giménez, Jaime, and Anabel Zárate-Marco. "A Dynamic Spatial Panel of Subnational GHG Emissions: Environmental Effectiveness of Emissions Taxes in Spanish Regions." Sustainability 12, no. 7 (April 3, 2020): 2872. http://dx.doi.org/10.3390/su12072872.
Повний текст джерелаАнотація:
In this paper we study the effectiveness of environmental taxes and policies of the regional level of government to reduce GHG emissions. We use panel data for the 17 Spanish regions in the period 1999–2017, controlling the spatial nexus between regions and using a dynamic Durbin model. The results show there is spatial dependence and spatio-temporal persistence of GHG emissions at the regional level in Spain, and that in this context, the taxes and policies intended to manage emissions introduce a slight disincentive to generating them. This fact, together with some relative decoupling which seems to exist between growth and emissions at the regional level, would suggest the need for tougher measures to combat environmental pollution in order to meet EU commitments.
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Hu, Shuyun, Dazhuan Ge, Guojian Hu, Jingwen Sun, Yingyi Ma, Mengqiu Lu, and Yuqi Lu. "The Patterns and Mechanisms of Land Price Divergence in Multiple Industries from the Perspective of Element Flows: The Case of the Yangtze River Delta, China." Land 11, no. 2 (January 25, 2022): 188. http://dx.doi.org/10.3390/land11020188.
Повний текст джерелаАнотація:
An in-depth exploration of the inner mechanisms of the spatio-temporal evolution of land prices in multiple industries (residential, commercial service and industrial) is of great significance for improving the overall economic development efficiency and resource allocation capacity of the region. Based on urban land price transaction data provided by the China Land Market Network, 307 county-level units in the Yangtze River Delta were used as the study area and spatial auto-correlation and spatio-temporal hotspot analysis were used to explore the spatial variation and temporal changes of land prices in multiple industries in the Yangtze River Delta from 2008 to 2018. The three-dimensional driving theory of land “demand + supply + market” was used as the basis to construct the index system of influential factors and the Spatial Durbin Model was used to explore the mechanism of the spatio-temporal variation of land prices in multiple industries. The results show that the land prices of multiple industries in the Yangtze River Delta are generally high in the east and low in the west and high in the south and low in the north, which is spatially consistent with the level of regional economic development. Due to the disparity in economic development between the regions, factors such as population, capital, technology and information are redistributed and fed into each other’s cycles between cities. The resulting spatial differences in land market supply and demand are intrinsic to the spatial differentiation of urban land prices. It is further proposed that land prices are a monetized expression of the abundance of resources in a city and that land prices are determined by the combined ability of regional resource factors to be allocated. Thus, land price differentiation reflects differences in the level of comprehensive regional development. Finally, the dynamic interaction of various factors on land values is used to promote the division of urban functions and regional economic development, which is an effective way to promote high-quality integrated regional development.
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Zhang, Shumin, Yongze Lv, and Baolei Zhang. "Spatio-Temporal Evolution and Influencing Factors of Green Development in the Yellow River Basin of China." Sustainability 14, no. 19 (September 29, 2022): 12407. http://dx.doi.org/10.3390/su141912407.
Повний текст джерелаАнотація:
Globally, nations and regions have pushed for “green development (GD)”, a sustainable development strategy that considers the integrated growth of “economy–environment–society”. As it is an area of China that provides an ecological function and is an important energy base, it is necessary to explore the current situation and factors influencing GD in the Yellow River Basin (YRB). Therefore, first, this paper constructs a GD indicator system from a multi-dimensional perspective, measures the GD of 79 prefecture-level cities in the YRB from 2006 to 2019 by using the entropy method, and analyzes the evolution of time series according to the results. We found that the YRB’s GD showed an overall increase during the study period, rising from 0.1261 to 0.2195, but the level was low. Second, we analyzed the spatial characteristics of the YRB’s GD using a spatial analysis method and concluded that GD varied significantly across cities in the YRB. The YRB presented spatial distribution characteristics with obvious “quad-core pieces”, and there was a high intensity of spatial correlation and agglomeration. The spatial center of gravity of GD moved toward the southeast year by year. Third, we examined the influencing factors of the GD of the YRB through the spatial Durbin model. The study found that the spatial spillover effect on GD in the YRB was obvious, and the reasons affecting the GD of the YRB were heterogeneous. Finally, according to the conclusions of this research, we propose differentiated policies that are suitable for GD in the YRB.
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Jankiewicz, Mateusz, and Elżbieta Szulc. "Analysis of Spatial Effects in the Relationship between CO2 Emissions and Renewable Energy Consumption in the Context of Economic Growth." Energies 14, no. 18 (September 15, 2021): 5829. http://dx.doi.org/10.3390/en14185829.
Повний текст джерелаАнотація:
The paper presents a spatial approach to the analysis of the relationship between air pollution, economic growth, and renewable energy consumption. The economic growth of every country is based on the energy consumption that leads to an increase in national productivity. Using renewable energy is very important for the environmental protection and security of the earth’s resources. Promoting environmentally friendly operations increases awareness of sustainable development, which is currently a major concern of state governments. In this study, we explored the influence of economic growth and the share of renewable energy out of total energy consumption on CO2 emissions. The study was based on the classical environmental Kuznets curve (EKC) and enriched with the spatial dependencies. In particular, we determined the spatial spillovers in the form of the indirect effects of changes in renewable energy consumption of a specific country on the CO2 emissions of neighboring countries. A neighborhood in this study was defined by ecological development similarity. The neighborhood matrix was constructed based on the values of the ecological footprint measure. We used the spatio-temporal Durbin model, with which the indirect effects were determined in relation to the spatially lagged renewable energy consumption. The results of our study also show the strength of the effects caused by imitating actions from the states with high levels of environmental protection. The study was conducted using data for 75 selected countries from the period of 2013–2019. Cumulative spatial and spatio-temporal effects allowed us to determine (1) the countries with the greatest impact on others and (2) the countries that follow the leading ones.
Дисертації з теми "Spatio-temporal Durbin model"
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Mashayamombe, Chipo. "A rat model study of the spatio-temporal effects of progesterone signalling on the transcriptome of uterine tissues during pregnancy and parturition." Thesis, University of Warwick, 2015. http://wrap.warwick.ac.uk/79940/.
Повний текст джерелаАнотація:
The steroid hormone progesterone is essential for the maintenance of pregnancy in mammalian species, but its role at term and during labour is not fully understood. While the effects of progesterone be either genomic or non-genomic, this thesis focuses on the genomic effects of progesterone, and its withdrawal, on rat uterine tissues. Using laser Capture Microdissection, homogeneous cell populations from the the outer myometrium, inner myometrium, and decidua basalis were isolated from uterine horns obtained from timed-pregnant Sprague Dawley rats that were randomised to receive either progesterone, mifepristone, or vehicle treatment. These rats had a 22-day gestational period, with natural systemic withdrawal of progesterone occurring on the 19th day of gestation (GD19). RNA sequencing was employed in the examination of the transcriptomes of the uterine layers, as well as gene expression profiling between GD19 and term. Analysis of the spatial expression of mRNA and proteins in the uterine tissues revealed localisation of thyrotropin-releasing hormone mRNA, as well as the Trh protein, to the decidua in late pregnancy. In addition, tenascin-n mRNA and proteins localised to the inner myometrium but not the outer myometrium during late pregnancy. Analysis of the temporal expression of mRNA transcripts showed distinct patterns of expression within each of the analysed tissues. Following the withdrawal of progesterone on GD19, changes first occur in the outer myometrium, followed by the inner myometrium, then the decidua where mRNA expression increases between GD22 before labour and GD22 during labour. In conclusion, this thesis presents a novel approach in which rat uterine tissues were studied separately. Potential tissue-specific markers for the decidua and the inner myometrium in late pregnancy were identified. The increase in gene expression prior to labour in the decidua would suggest a signal for the onset of labour. Furthermore, changes in the myometrial tissues suggest the presence of an in-built mechanism through which the myometrium knows when to prepare for labour.
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Ciardo, Diletta. "Quantitative analysis of the regulation of the DNA replication program by the intra-S phase checkpoint in Xenopus embryos Checkpoint control of the spatio-temporal regulation of DNA replication in Xenopus early embryos Polo-like kinase 1 (Plk1) is a positive regulator of DNA replication in the Xenopus in vitro system On the Interplay of the DNA Replication Program and the Intra-S Phase Checkpoint Pathway Genome wide decrease of DNA replication eye density at the midblastula transition of Xenopus laevis Polo like kinase 1 promotes dispersed replication origin firing during S phase." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS478.
Повний текст джерелаАнотація:
Dans les organismes multicellulaires, plusieurs millier d’origines initient la réplication de l'ADN. Elles sont regroupées en domaines qui se répliquent tôt ou tard au cours de la phase S (origines précoces ou tardives). L'un des mécanismes régulant le programme de réplication est un point de contrôle intra phase S qui dépend des kinases ATR et Chk1. Cette voie est activée par un stress réplicatif engendré par le blocage des fourches de réplication aux origines précoces, en retour elle inhibe l’activation des origines tardives. Il a été proposé, que la protéine Polo-Like-Kinase 1 (Plk1) soit responsable du déclenchement des origines situées à proximité des fourches bloquées en cas de stress réplicatif. Cependant, aucune analyse de l’activation des origines n’a jamais été réalisée au cours d’une phase S non perturbée lorsque Plk1 est absente. Pour avoir une vue globale et unifiée du processus de réplication de l'ADN, des modèles numériques et analytiques ont été construits dans le passé, mais aucun d'eux n'intègrent le rôle de Chk1 et Plk1. L'objectif de ma thèse était d’étudier expérimentalement et analytiquement de quelle manière Chk1 peut réguler le déclenchement des origines dans l'espace et dans le temps. En particulier, de comprendre si Plk1 pouvait être impliquée dans cette régulation pendant une phase S non perturbée, à cette fin, j'ai utilisé le système réplicatif des extraits d’œuf de Xénopes. En premier lieu, j'ai intégré dans un modèle numérique l’action de Chk1 pour reproduire le programme de réplication du système Xénope. J'ai testé différents scénarios puis j’ai utilisé des données de peignage d'ADN obtenues précédemment dans des conditions d'inhibition de la kinase Chk1. Les simulations Monte Carlo obtenues ont été ajustées aux données expérimentales en optimisant les valeurs des paramètres libres des modèles. J'ai trouvé qu'il fallait ajouter deux hypothèses aux modèles de réplication développés précédemment: 1) la présence d’une forte inhibition du déclenchement des origines par Chk1 à partir du début de la phase S 2) la présence de domaines génomiques répliquant précocement et qui échappent à cette inhibition. Deuxièmement, j'ai montré expérimentalement que, Plk1 actif est recrutée sur la chromatine avant le début de la phase S non perturbée et qu'en l'absence de Plk1, la réplication de l'ADN est ralentie. De plus, l’absence de Plk1 entraîne une augmentation de la phosphorylation de Chk1 et une diminution de l’activité de la kinase Cdk2, ce qui suggère que Plk1 inhibe Chk1. En réalisant des expériences de peignage d’ADN, j'ai démontré qu’en l’absence de Plk1 on observe une baisse du niveau d’activation des origines. L'analyse de ces données par mon modèle numérique suggère que Plk1 régule négativement l’action de Chk1 levant ainsi son action inhibitrice sur l’activation globale des origines. Cet effet concorde avec mes observations expérimentales. Il semble cependant que Plk1 n’agisse pas à proximité directe des fourches de réplication, comme cela avait été proposé précédemment. Enfin, en assimilant le processus de réplication à un processus de nucléation et de croissance unidimensionnel, j'ai développé une nouvelle approche quantitative pour étudier la régulation du programme de réplication. Cette approche lie la similarité entre les profils spatiaux de réplication d'une molécule unique et les processus de régulation de la réplication de l'ADN. En analysant les données de peignage d'ADN, j'ai montré que le programme de réplication de l'ADN des embryons précoces de Xénope est régulé par deux processus exclusifs dans l'espace et dans le temps. L’un avec une fréquence faible d’activation des origines et une vitesse apparente de fourches élevée et un second, régulé par Plk1, présentant une fréquence d’activation élevée des origines avec une vitesse apparente de fourches faibleThe initiation of DNA replication in multicellular organisms starts from several thousand genomic loci called replication origins. They are grouped into domains which replicate early or late during S phase. The firing of a replication origin creates two diverging replication forks that replicate flanking DNA. One of the mechanisms regulating DNA replication program is the ATR/Chk1 dependent intra-S phase checkpoint. This pathway is activated by replicative stress due to stalled replication forks at early firing origins and in turn, inhibits the late firing of origins. It has been proposed that the checkpoint recovery kinase Plk1 (Polo-Like-Kinase 1) could be responsible for allowing origin firing close to stalled forks in replication stress conditions. However, origin firing has not been analysed after Plk1 inhibition or depletion during unperturbed S phase. To assemble a comprehensive and unified view of the DNA replication process numerical and analytical models have been built in the past, but none of them integrates the role of checkpoint pathways. The goal of my thesis was to investigate experimentally and analytically how the checkpoint regulates the firing of origins in space and time and, in particular, whether the Plk1 is implicated in the regulation of origin firing during unperturbed S phase. To this end, I used the Xenopus in vitro system. First, I integrated in a numerical model the checkpoint pathway to describe the replication program in the Xenopus in vitro system. I tested different scenarios and used DNA combing data previously obtained by the laboratory after the inhibition of the checkpoint kinase Chk1. Monte Carlo simulated data were fitted to experimental data by optimizing the values of free parameters of models using a genetic algorithm. I found that two new hypothesis should be added to formerly built replication models: 1) a strong inhibition of origin firing by Chk1 from the beginning of S phase 2) the presence of early replicating genomic domains that evade the origin firing inhibition. Second, I experimentally showed that during unperturbed S phase active Plk1 is recruited to chromatin before the start of S phase and that in the absence of Plk1, DNA replication is slowed down. Moreover, Plk1 depletion led to an increase in Chk1 phosphorylation (p-Chk1) and a decrease of Cdk2 activity, suggesting that Plk1 inhibits the intra-S phase checkpoint. Performing DNA combing, I demonstrated that Plk1 depletion leads to a decrease in origin firing level. Analysis of the combing data by the developed numerical model suggested that during unchallenged S phase Plk1 down regulates the global origin firing inhibitory action of Chk1, consistent with the experimental observation of increased level of p-Chk1 in Plk1 depleted Xenopus egg extract. However, Plk1 does not seem to act close to replication forks as was proposed earlier. Finally, by considering replication process as a one-dimensional nucleation and growth process and using statistical methods, I developed a new quantitative approach to study the regulation of replication program. This approach links the similarity between single molecule replication patterns to DNA replication regulating processes. By analyzing DNA combing data, I showed that DNA replication program in Xenopus early embryos is regulated by two spatially and temporally exclusive processes. One with low frequency of origin firing and high apparent fork speed and a second, controlled by PlK1, with a high frequency of origin firing and a low apparent fork speed. Altogether my results demonstrate that Plk1 positively regulates replication origin firing during normal S phase by down regulating the replication checkpoint. The numerical model predicts the existence of replication timing domains in the Xenopus model system. Future work will show whether Plk1 regulates the replication program at the level of genomic domains
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Mannaf, Maksuda. "Examining the spatial influences of natural capital in the Australian agricultural landscape." Thesis, 2021. https://hdl.handle.net/2440/132861.
Повний текст джерелаАнотація:
Overall, this thesis seeks to explore – using three case studies - the environmental and economic influences and outcomes of on-farm natural capital in the Australian agricultural landscape over space and time. In particular, it explored: 1) the spatial influences on the adoption of certified organic farming (which is used as a proxy indicator of natural capital conservation technologies) at a regional level in Australia using agricultural census data from 2010/11 and 2015/16; 2) the association between the presence of certified organic farming and regional biodiversity at the postcode level over sixteen years in South Australia; and 3) the association between farm land value and natural capital in the forms of native woody vegetation coverage and climate in South Australia over sixteen years. The first case study focused on Australia as a whole and modelled farmers’ adoption behaviour of certified organic farming (using it as a proxy for sustainable agriculture technologies to conserve on-farm natural capital such as soil, water, and biodiversity). Spatial diffusion of organic farming represents an interesting case study, given the large amount of skills and knowledge regarding management of natural resources that organic farmers need to apply/learn for their farms’ viability. Although farmers’ adoption and diffusion behaviour is well studied in the literature, modelling of the role of spatial spill-over effects on diffusion intensity, especially in regards to the adoption of organic farming, is not well known. This thesis uses national Australian agricultural census data from 2010/11 and 2015/16 and a SLX Tobit model (N=2,134) to model the influences on the intensity of the diffusion of organic farming (namely percentage of organic land holding) in regional areas, and found statistically significant local spatial spill-over effects from neighbouring regions’ characteristics. In addition, a higher share of organic farmland in regions is associated with regional characteristics such as: larger irrigated farms; lower stocking rates; increased proportion of grazing and horticultural land; increased labour supply; increased green vegetation; rural areas with low human population density; and higher community income. The second study explored the associations between farmers’ land use behaviour (i.e. the extent of certified organic farming in a region) and regional biodiversity outcomes (vascular plant and bird species richness) at the postcode level. This study put together a new dataset on certified organic farming presence and locations in South Australia, using databases from organic certifiers. The spatial association between biodiversity indicators and organic farming was analysed using a spatial Durbin error model, while controlling for the effects of landscape attributes, human population footprint, climate and productivity from 2001 to 2016 (N=5,456) in South Australia. The results found that increased organic farming presence in postcode areas had a statistically significant positive association with vascular plant species richness, but little to no statistically significant association was found for bird species richness. Environmental heterogeneity in terms of land cover diversity, elevation range, and plant productivity seems to be the other prime determinants of plant and bird species richness. The third study focused on the association between native woody vegetation on agricultural properties and their economic values in South Australia, using both sales and valuation prices of agricultural properties from 1998 to 2013 (N=10,513). Findings from the spatio-temporal Durbin model revealed that the presence of native woody vegetation on agricultural properties significantly increased the per hectare market price (i.e. price sold in the market), but at a decreasing rate as the proportion of vegetation increased. The marginal return of vegetation was highest for small size properties and lowest for larger properties. In addition, the direct effects of increased annual rainfall, increased soil natural productivity, increased market accessibility, proximity to locational amenities, smaller size properties, availability of irrigation, and higher commodity price were also positively capitalised into sales prices. On the other hand, increased drought and high soil erodibility significantly reduced per hectare sales prices. Comparing valuation price models with sales price models, it was found that the valuation prices seem to undervalue the presence of native vegetation on agricultural properties and hence provide weaker evidence of the value of on-farm natural capital in the South Australian context.Thesis (Ph.D.) -- University of Adelaide, Centre for Global Food and Resources, 2021
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Brackenhammer, Ulrich. "Spatio-temporal pattern formation during CO oxidation on Pt(110) models of subsurface oxygen kinetics /." 1994. http://catalog.hathitrust.org/api/volumes/oclc/33025483.html.
Повний текст джерелаАнотація:
Thesis (M.S.)--University of Wisconsin--Madison, 1994.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 213-139).
Книги з теми "Spatio-temporal Durbin model"
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Lopes, Hedibert, and Nicholas Polson. Analysis of economic data with multiscale spatio-temporal models. Edited by Anthony O'Hagan and Mike West. Oxford University Press, 2018. http://dx.doi.org/10.1093/oxfordhb/9780198703174.013.12.
Повний текст джерелаАнотація:
This article discusses the use of Bayesian multiscale spatio-temporal models for the analysis of economic data. It demonstrates the utility of a general modelling approach for multiscale analysis of spatio-temporal processes with areal data observations in an economic study of agricultural production in the Brazilian state of Espìrito Santo during the period 1990–2005. The article first describes multiscale factorizations for spatial processes before presenting an exploratory multiscale data analysis and explaining the motivation for multiscale spatio-temporal models. It then examines the temporal evolution of the underlying latent multiscale coefficients and goes on to introduce a Bayesian analysis based on the multiscale decomposition of the likelihood function along with Markov chain Monte Carlo (MCMC) methods. The results from agricultural production analysis show that the spatio-temporal framework can effectively analyse massive economics data sets.
Частини книг з теми "Spatio-temporal Durbin model"
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Carpita, Maurizio, and Rodolfo Metulini. "Modelling the spatio-temporal dynamic of traffic flows with gravity models and mobile phone data." In Proceedings e report, 99–104. Florence: Firenze University Press, 2021. http://dx.doi.org/10.36253/978-88-5518-461-8.19.
Повний текст джерелаАнотація:
The analysis of origin-destination traffic flows may be useful in many contexts of application (e.g., urban planning, tourism economics) and have been commonly studied through the gravity model, which states that flows are proportional to ''masses" of both origin and destination, and inversely proportional to distance between them. Using data on the flow of mobile phone SIM among different aree di censimento, recorded hourly basis for several months and provided by FasterNet in the context of MoSoRe project, in this work we characterize and model the dynamic of such flows over the time in the strongly urbanized and flood-prone area of the Mandolossa (western outskirts of Brescia, northern Italy), with the aim of predicting the traffic flow during flood episodes. Whereas a traditional ”static” mass explanatory variable is represented by residential population (Pop), or by gross domestic product (GDP), here we propose to use a most accurate set of explanatory variables in order to better account for the dynamic over the time. First, we employ a time-varying mass variable represented by the number of city-users by area and by time period, which has been estimated from mobile phone data (provided by TIM) using functional data approach and already adopted to derive crowding maps for flood exposure. Secondly, we include in the model a proper set of factors such as areal and time dummies, and a novel set of indices related to (e.g.) the number and the type of streets, the number of offices, restaurants or cinemas, which may be retrieved from OpenStreetMap. The joint use of these two novel sets of explanatory variables should allow us to obtain a better linear fitting of the gravity model and a better traffic flow prediction for the flood risk evaluation.
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Mallick, Chinmoy, Mainak Bandyopadhyay, and Rajesh Kumar. "Evolution of Microwave Electric Field on Power Coupling to Plasma during Ignition Phase." In Selected Topics in Plasma Physics. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.92011.
Повний текст джерелаАнотація:
During the gas ignition process, the plasma and the microwave electric fields are evolved with time together in the plasma volume. The spatio-temporal evolution pattern of microwave-radiated plasma parameters is reported here, highlighting the role of these electric fields on power coupling processes. Evolutions of electric field and so power coupling processes are calculated using the finite element method (FEM). It is observed that the main power coupling mechanism is electron cyclotron resonance (ECR) method; however, with the evolution of plasma, the mode shifts from ECR to off-ECR-type heating with time. Off-ECR heating in the form of upper hybrid resonance (UHR) method, electrostatic (ES) ion acoustic wave heating method is important heating mechanisms during highly dense plasma condition, when density is above critical density for launched frequency, 2.45 GHz. The conclusions on the shifting of heating mechanisms are also drawn based on the 3D maps of spatio-temporal plasma density and hot electron temperature evolution.
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Castel-Clavera, Jorge, François Pimont, Thomas Opitz, Julien Ruffault, and Jean-Luc Dupuy. "Modelling the influence of regional landscape drivers on spatio-temporal patterns of wildfire activity." In Advances in Forest Fire Research 2022, 1228–33. Imprensa da Universidade de Coimbra, 2022. http://dx.doi.org/10.14195/978-989-26-2298-9_186.
Повний текст джерелаАнотація:
Identifying the drivers of fire activity’s spatio-temporal variability is challenging in densely populated and fire prone landscapes. Human usage and climate affect the local fire regime in contrasting ways. The identification of these drivers is further complicated due to the stochastic nature of fire activity. Fire regimes in Mediterranean France show contrasted spatial patterns and temporal changes at decadal scales. While overall, the number of fires decreased over the last thirty years, certain zones suffered local increases in fire activity. To describe and understand the drivers of those changes and the spatial variability, we introduced several improvements in the Firelihood model - a probabilistic framework capable of prediction fire occurrence of >1ha fires, and exceedance probabilities of 10 and 100 ha thresholds - by incorporating Land-Use Land-Cover (LULC) explanatory variables, as well as by enhancing its spatio-temporal components to account for unexplained variability in models. The novel model - fitted on a 2km-pixel grid, but relying on variables aggregated at various spatial aggregations (2, 4, 8 and 16km) - is used to explain the observed spatial patterns of fire activity during the last 27 years, as well as the regional and local changes observed between two decades with contrasted fire activities by running counterfactual scenarios. LULC variables, including road density, wildland-urban interface, or expert-based fuel type rating explain a significant part (as much as fire-weather) of the variability in fire occurrence (>1ha), thereby reducing the effect of unexplained spatial variability. The selected occurrence model uses only 2km-resolution variables, as local factors have a high influence on fire ignition and initial spread. The occurrence of larger fire (>10 ha or >100 ha) is largely driven by fire-weather, followed by unexplained spatial variability; selected models for larger fires uses a few LULC variables aggregated at 4, 8 and/or 16 km. This indicates the influence of surrounding factors on fire size extension. The spatial effect for fire occurrence presents contrasted hot and cold-spots throughout the area, while it has a clear east to west decreasing trend for fire size. Regarding temporal changes in fire activity between the two decades, changes in fire weather induced a strong increase in fire probability in many hot spots throughout the region, but this effect was overcompensated by a negative trend associated with unexplained temporal factors (and of larger magnitude than fire weather). LULC variables had negligible effect on the fire regime’s temporal trends. Moreover, an east-to-west gradient appears for the spatial trends of the larger fires, and for the temporal trends in all sizes, highlighting the increase in fire activity in the western side of the region. Those results suggest that observed temporal changes in fire activity are the result of a changing socio-economic or policy frame, probably related to reinforced suppression policies following the year 2003, and the increasing agricultural abandonment.
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Tian, Yichao, and Yongwei Yang. "Spatio-Temporal Variation of Ecosystem Services and Its Trade-off Relationships in Southwest Guangxi." In Challenges and Opportunity in Agrometeorology [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.101755.
Повний текст джерелаАнотація:
Identifying the mutual relationship between ecosystem services in southwest Guangxi can jointly optimize a variety of services to avoid damaging others while improving one service, which is of great significance for promoting the sustainable management of regional ecosystem, guiding the rational development of natural resources and improving human well-being. Based on remote sensing data, land use data, meteorological data and DEM data, with the support of Carnegie-Ames-Stanford Approach (CASA) model, Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model and Revised Universal Soil Loss Equation (RUSLE) model, this paper studies the changing characteristics of typical ecosystem services in southwest Guangxi and explores the mutual relationship between different ecosystem services. The results showed that the mean change trend of the whole vegetation net primary productivity (NPP) has been increasing in the study area over the past 19 years. In the past 19 years, water conservation in southwest Guangxi has shown a fluctuating upward trend, with the growth rate of water conservation quality 255.88 mm/hm−2·a−1. During the study period, the range of soil retention variation to the total of 65.38–96.88 t/hm−2·a−1 increased 22.73 t/hm−2·a−1, with a mean of 79.19 t/hm−2·a−1. Vegetation NPP in the study area is synergistic with soil conservation and water conservation, and soil conservation with water conservation as well.
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Gonzalez, Hector, Jiawei Han, Hong Cheng, and Tianyi Wu. "Warehousing RFID and Location-Based Sensor Data." In Intelligent Techniques for Warehousing and Mining Sensor Network Data, 50–71. IGI Global, 2010. http://dx.doi.org/10.4018/978-1-60566-328-9.ch003.
Повний текст джерелаАнотація:
Massive Radio Frequency Identification (RFID) datasets are expected to become commonplace in supply-chain management systems. Warehousing and mining this data is an essential problem with great potential benefits for inventory management, object tracking, and product procurement processes. Since RFID tags can be used to identify each individual item, enormous amounts of location-tracking data are generated. Furthermore, RFID tags can record sensor information such as temperature or humidity. With such data, object movements can be modeled by movement graphs, where nodes correspond to locations, and edges record the history of item transitions between locations and sensor readings recorded during the transition. This chapter shows the benefits of the movement graph model in terms of compact representation, complete recording of spatio-temporal and item level information, and its role in facilitating multidimensional analysis. Compression power and efficiency in query processing are gained by organizing the model around the concept of gateway nodes, which serve as bridges connecting different regions of graph, and provide a natural partition of item trajectories. Multi-dimensional analysis is provided by a graph-based object movement data cube that is constructed by merging and collapsing nodes and edges according to an application-oriented topological structure.
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Pong, Beryl. "Introduction." In British Literature and Culture in Second World Wartime, 1–25. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780198840923.003.0001.
Повний текст джерелаАнотація:
The introduction examines how writers anticipated the Second World War in the interwar period, and why dread became a pervasive experience in the 1930s and 1940s. Beginning with the problem of how to define the spatio-temporal boundaries of modern wartime, it argues that, with war looming, modernist time philosophy gradually shifted focus from the past to the future. The chapter then presents a model for understanding Second World Wartime through the concept of late modernist chronophobia. As a war understood to be a repetition of the First World War, but whose effects were expected to be more catastrophic and total, it is characterized by a fear of time itself. During the Blitz, this is enacted on a local level on the home front, through the temporalities of aerial bombardment. The chapter discusses why, as a bridge between the memory of the First World War and the incipient temporalities of the Cold War, the Second World War is crucial to understanding how modern wartime developed in the twentieth century.
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Vlach, Marek. "The Antonine Plague." In Simulating Roman Economies, 69–108. Oxford University PressOxford, 2022. http://dx.doi.org/10.1093/oso/9780192857828.003.0003.
Повний текст джерелаАнотація:
Abstract Since the beginning of discussions about the ‘third-century crisis’, the famous epidemic called the Antonine Plague has often been argued to be a key causal factor. During the crisis period, different segments and regions of the Roman world underwent various forms of turmoil (social unrest and uprising, economic problems, political instability, etc.) or external incursions (warfare, barbarian raids). Our current knowledge of the period suggests considerable ranges of the estimated death toll of the epidemic. The main intention of this chapter is to test the plausibility of these different estimated impacts on the basis of emulative digital modelling and simulation. A geographically explicit context, with a cellular framework, represents a workspace for spatio-temporal quantitative simulations to test various scenarios. Model input data include a reconstructed distribution of population density, infrastructural density, historical clinical data on the disease, and other factors. The vital part of simulation dynamics is defined through epidemiology mathematics (a compartment model with dynamics driven by differential equations). Coping with a large array of input variables, which are known only to a limited extent, has constrained our ability to test scenarios for assessing possible quantitative and spatial aspects of the epidemic impact within the demographic structures of the Roman Empire. Nevertheless, on the basis of simulation results it was possible to put the general plausibility of some existing estimates into a new perspective.
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Rushingabigwi, Gerard, Celestin Twizere, Philibert Nsengiyumva, Jean De Dieu Ntawangaheza, and Liguo Sun. "An Analysis of Remote Sensing Data to Evaluate the Problem of Atmospheric Aerosol Pollution in Africa." In Environmental Management [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.99377.
Повний текст джерелаАнотація:
The particulate matter (PM) directly endangers the human health. Remotely sensed tiny atmospheric particles, aerosols, are presented in this research as atmospheric air pollutants. Globally overviewed for the first instances, and then a focus put on Africa and Asia, the selected aerosols are fine particulates (PM2.5), black carbon (BC), and Sulfate (SO4). According to the existing literature, the motivation to research on air pollutants came from the fact that the polluted air globally kills many people, by attacking cardiovascular system. The online accessible remote sensing’s data has been mostly collected from the second version of modern era retrospective analysis for research and applications (MERRA-2), a model selected for its update as well as the fact that its data are directly assimilated from the most renown remote sensors: Moderate resolution Imaging Spectroradiometer (MODIS) and the advanced very high-resolution radiometer (AVHRR). MERRA-2 also compiles data from different aerosol robotic networks (AERONETs). With a vast region of interest, and considering the big temporal resolution, reduced spatio-temporal resolutions facilitated the focused research. Goddard interactive online visualization and analysis infrastructure (GIOVANNI) bridged our research objectives with the data; Geographical Information Systems (Arc GIS) is a main software tool. Map-based as well as time series results for PM2.5 and other atmospheric air pollutants are presented; health dangers associated with the dust from erstwhile research highlighted. Finding that the annually-averaged mass concentration of the dust’s PM2.5 is significantly greater than the mean recommended concentration, 25 μg/m3, in all the seasons of the center of the research region of interest (Africa), this research recommends further research on dust aerosols mitigation strategies, during the seasons of heaviest air pollutants in particular.
Тези доповідей конференцій з теми "Spatio-temporal Durbin model"
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Qiao, Chi, and Andrew T. Myers. "Modeling Spatio-Temporal Characteristics of Metocean Conditions During Hurricanes Using Deep Neural Networks." In ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/omae2020-18989.
Повний текст джерелаАнотація:
Abstract Surrogate modeling of the variability of metocean conditions in space and in time during hurricanes is a crucial task for risk analysis on offshore structures such as offshore wind turbines, which are deployed over a large area. This task is challenging because of the complex nature of the meteorology-metocean interaction in addition to the time-dependence and high-dimensionality of the output. In this paper, spatio-temporal characteristics of surrogate models, such as Deep Neural Networks, are analyzed based on an offshore multi-hazard database created by the authors. The focus of this paper is two-fold: first, the effectiveness of dimension reduction techniques for representing high-dimensional output distributed in space is investigated and, second, an overall approach to estimate spatio-temporal characteristics of hurricane hazards using Deep Neural Networks is presented. The popular dimension reduction technique, Principal Component Analysis, is shown to perform similarly compared to a simpler dimension reduction approach and to not perform as well as a surrogate model implemented without dimension reduction. Discussions are provided to explain why the performance of Principal Component Analysis is only mediocre in this implementation and why dimension reduction might not be necessary.
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Medic, Tomislav, Nicholas Meyer, Lorenz Schmid, and Andreas Wieser. "Vibration monitoring of a bridge using 2D profile laser scanning: Lessons learned from the comparison of two spatio-temporal processing strategies." In 5th Joint International Symposium on Deformation Monitoring. Valencia: Editorial de la Universitat Politècnica de València, 2022. http://dx.doi.org/10.4995/jisdm2022.2022.13813.
Повний текст джерелаАнотація:
Profile laser scanning allows sub-millimeter precise contact-free measurements with high spatial and temporal resolution. That makes it an appealing solution for structural health monitoring focusing on vibrations of engineering structures, such as the analysis of eigenmodes and eigenfrequencies of bridges. In this work, we use the profile scanning mode of a Zoller+Fröhlich Imager 5016 terrestrial laser scanner (TLS) to observe bridge dynamics, focusing on the free decay processes following trains passing the bridge and exciting the structure. We compare two vibration monitoring strategies and implement an open-source semi-automatic software that integrates both approaches. We successfully estimate a spatio-temporal vibration model (including dampening coefficient) despite the maximum vibration amplitude reaching only 0.3 mm during the free decay process. Both strategies allow the estimation of the first eigenfrequency with a precision better than 0.1 Hz. Within the paper, we highlight the advantages and tackle the identified challenges of these vibration monitoring strategies. We also report on a preliminary investigation of appropriate instrument positioning for estimating the parameters of a spatio-temporal vibration model.
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Tanaka, Taiji, Hyun Jin Park, Yuji Tasaka, and Yuichi Murai. "Void Waves Developing in Gas-Liquid Two-Phase Turbulent Boundary Layers Beneath a Flat Bottom Model Ship." In ASME-JSME-KSME 2019 8th Joint Fluids Engineering Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/ajkfluids2019-5272.
Повний текст джерелаАнотація:
Abstract To investigate the development process of a void wave, spatio-temporal fluctuation of void fraction, we examined experimentally a turbulent boundary layer with bubble injections. The experiments performed on a flat bottom of 4-mlong transparent model ship towed in a tank of 100 m length with the speed of up to 3.00 m/s. In bubbles injection with constant air flow rate, void fluctuations with 4 Hz or 8 Hz appeared dependent on the towing speed. With periodically fluctuated air flow rate, artificial void waves were provided into the turbulent boundary layer and their frequency was maintained during the downstream propagation. The attenuation rate of the fluctuation evaluated using Fourier analysis of the wave took the minimum value at specific injection frequency conditions.
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Saha, Homagni, Tianshuang Gao, Hamid Emadi, Zhanhong Jiang, Arti Singh, Baskar Ganapathysubramanian, Soumik Sarkar, Asheesh Singh, and Sourabh Bhattacharya. "Autonomous Mobile Sensing Platform for Spatio-Temporal Plant Phenotyping." In ASME 2017 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/dscc2017-5207.
Повний текст джерелаАнотація:
This paper presents the design, modeling, control and navigation for a novel ground-based mobile sensing platform that can collect multi-modal data in agricultural research farms for high throughput modular plant phenotyping. The platform will have the following capabilities (i) Navigate in a row-crop farm to collect data with minimal human intervention during operation (ii) Autonomous decision making i.e, it can take its own decisions for maximizing the value of information of the acquired data and (iii) Scalable in terms of the size of the farmland. The design requirements for such a platform or robot is formulated, and a detailed discussion on realizing such a design is presented. The dynamics of the robot is presented in the state space form and it is abstracted in the form of a control flow diagram for the automatic steering system. An adaptive sampling approach has been taken to generate an estimated belief-space which is leveraged in the proposed opportunistic sensing scheme to generate way-points for navigation.
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Becker, Adam, Marek Kapitz, and Stefan aus der Wiesche. "Numerical Simulation of Single Bubble Dynamics During Pool and Flow Boiling Conditions." In ASME 2012 Heat Transfer Summer Conference collocated with the ASME 2012 Fluids Engineering Division Summer Meeting and the ASME 2012 10th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/ht2012-58089.
Повний текст джерелаАнотація:
Complete three-dimensional numerical simulations of single bubble dynamics under pool and flow boiling conditions are carried out using the CFD code FLOW3D© based on the volume-of-fluid (VOF) method. The analyses include a numerically robust kinetic phase change model and transient wall heat conduction. The simulation approach is calibrated by comparison with available experimental and theoretical data. It is found that the observed hydrodynamics (i.e. bubble shape, departure, and deformation) are simulated very well. The comparison with high-resolution transient temperature measurements during a heating foil experiment indicates that modeling of the spatio-temporal heat sink distribution during bubble growth requires major attention. The simulation tool is employed for single bubble dynamics during flow boiling, and the agreement is excellent with published experimental data. The numerical results indicate how bulk flow velocity and wall heat transfer influence the bubble and heat transfer characteristics.
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Yang, Xianglin, Yun Lin, Ruofan Liu, and Jin Song Dong. "Temporality Spatialization: A Scalable and Faithful Time-Travelling Visualization for Deep Classifier Training." In Thirty-First International Joint Conference on Artificial Intelligence {IJCAI-22}. California: International Joint Conferences on Artificial Intelligence Organization, 2022. http://dx.doi.org/10.24963/ijcai.2022/558.
Повний текст джерелаАнотація:
Time-travelling visualization answers how the predictions of a deep classifier are formed during the training. It visualizes in two or three dimensional space how the classification boundaries and sample embeddings are evolved during training. In this work, we propose TimeVis, a novel time-travelling visualization solution for deep classifiers. Comparing to the state-of-the-art solution DeepVisualInsight (DVI), TimeVis can significantly (1) reduce visualization errors for rendering samples’ travel across different training epochs, and (2) improve the visualization efficiency. To this end, we design a technique called temporality spatialization, which unifies the spatial relation (e.g., neighbouring samples in single epoch) and temporal relation (e.g., one identical sample in neighbouring training epochs) into one high-dimensional topological complex. Such spatio-temporal complex can be used to efficiently train one visualization model to accurately project and inverse-project any high and low dimensional data across epochs. Our extensive experiment shows that, in comparison to DVI, TimeVis not only is more accurate to preserve the visualized time-travelling semantics, but 15X faster in visualization efficiency, achieving a new state-of-the-art in time-travelling visualization.
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Desmars, Nicolas, Yves Pérignon, Guillaume Ducrozet, Charles-Antoine Guérin, Stephan T. Grilli, and Pierre Ferrant. "Phase-Resolved Reconstruction Algorithm and Deterministic Prediction of Nonlinear Ocean Waves From Spatio-Temporal Optical Measurements." In ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/omae2018-78367.
Повний текст джерелаАнотація:
We investigate a nonlinear phase-resolved reconstruction algorithm and models for the deterministic prediction of ocean waves based on a large number of spatio-temporal optical measurements of surface elevations. We consider a single sensor (e.g., LIDAR, stereo-video, etc.) mounted on a fixed offshore structure and remotely measuring fields of free surface elevations. Assuming a uniform distribution of measurement points over the sensor aperture angles, the density of free surface observation points geometrically decreases with the distance from the sensor. Additionally, wave shadowing effects occur, which become more important at small viewing angles (i.e., grazing incidence on the surface). These effects result in observations of surface elevation that are sparsely distributed. Here, based on earlier work by [1], we present and discuss the characteristics of an algorithm, aimed at assimilating such sparse data and able to deterministically reconstruct and propagate ocean surface elevations for their prediction in time and space. This algorithm could assist in the automatic steering and control of a variety of surface vehicles. Specifically, we compare prediction results using linear wave theory and the weakly nonlinear Choppy Wave Model [2, 3], extended here to an “improved” second order formulation. The latter model is based on an efficient Lagrangian formulation of the free surface and was shown to be able to model wave properties that are important to the proper representation of nonlinear free surfaces, namely wave shape and celerity. Synthetic datasets from highly nonlinear High Order Spectral simulations are used as reference oceanic surfaces. Predicted results are analyzed over an area that evolves in time, using the theoretical amount of information assimilated during the reconstruction of the wave field. For typical horizons of prediction, we discuss the capabilities of our assimilation process for each wave model considered.
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Rácz, Kornelius, Josh M. Inouye, and Francisco J. Valero-Cuevas. "The Spatio-Temporal Structure of Force Variability in Static Grasp Suggests a Continually Active Neural Controller." In ASME 2010 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2010. http://dx.doi.org/10.1115/sbc2010-19698.
Повний текст джерелаАнотація:
Fingertip forces during simple and static tripod grasp exhibit a surprisingly rich dynamics [1]. Here we explore the hypothesis that, even for this apparently simple manipulation task, these fluctuations are shaped by a neural controller rather than by signal-dependent motor noise. We fed band-limited noise processes scaled to mean force level into a 21-muscle model of 3-finger grasp, and compare model output with experimental force recordings. We find that the spatial and spectral characteristics of simulated force fluctuations differed greatly from those observed in actual static tripod grasp. In light of current literature [2], we propose that a continually active neural controller is at work even for this simplest example of multifinger manipulation.
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Iliopoulos, Athanasios, John G. Michopoulos, Virginia DeGiorgi, and Steven Policastro. "Towards a Computational Multiphysics Framework for Modeling Antibiofouling Processes." In ASME 2014 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/detc2014-35401.
Повний текст джерелаАнотація:
Biofouling is a process of major concern on naval vessels because it considerably affects their performance, maintenance and operational costs due to the fact that induces an increased hydrodynamic drag that leads to higher fuel consumption that in turn demands expensive cleaning procedures. A possible antibiofouling system can be designed by enhancing an existing impressed current cathodic protection system and taking advantage of the chlorine oxidants produced during its operation. In this work we present a design methodology for such a system, together with the associated multiphysics formulation framework based on a coupled chemical reactions — electric currents, species mass transport and electromigration model. This framework predicts the spatio-temporal distributions of the Chlorine species concentration that tend to inhibit the biofouling formations. We also demonstrate the applicability of the computational framework on a number of platforms ranging from simple panels up to a full scale boat. The computational results are compared with the actual field experiments.
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Snarski, Stephen R. "Measurement and Modeling of the Fluctuating Wall Pressure Field Beneath Transitional Boundary Layers." In ASME 2002 Joint U.S.-European Fluids Engineering Division Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/fedsm2002-31338.
Повний текст джерелаАнотація:
Measurements of the fluctuating wall pressure field across the transition region of a flat plate zero pressure gradient boundary layer have been performed with a 64-element linear array of sub-miniature hearing-aid microphones. The measurements provide a unique description of the formation, convection, and growth of turbulent spots in the transition zone and insight into a potential source of low-wavenumber energy. A model for the nonhomogeneous wavenumber-frequency spectrum has been formulated based on the observed spatio-temporal properties of the field. Measured array-averaged wavenumber-frequency spectral levels for the transitional boundary layer collapse with fully turbulent spectra in the vicinity of the convective ridge when scaled by intermittency, similar to previous findings for single point spectra. The transition zone convective ridge is broader, however, consistent with the notion of rapidly evolving (versus equilibrium) structures. Insight into the low-wavenumber portions of the spectra requires an improved array phase calibration. Wavelet based transform methods are being pursued to understand the evolution of spectral components during spot formation and to resolve the space-varying wavenumber content of the field.
Звіти організацій з теми "Spatio-temporal Durbin model"
1
Kwon, Jaymin, Yushin Ahn, and Steve Chung. Spatio-Temporal Analysis of Roadside Transportation-Related Air Quality (StarTraq 2021): A Characterization of Bike Trails and Highways in the Fresno/Clovis Area. Mineta Transportation Institute, November 2022. http://dx.doi.org/10.31979/mti.2022.2128.
Повний текст джерелаАнотація:
The San Joaquin Valley is identified as an area with a high level of particulate matter (PM) in the air, reaching above the federal and state clean air standards (EPA 2019). Many of the cities in the valley are classified as the most polluted cities in the United States for both particulate matter and ozone pollution (American Lung Association, 2021). To resolve this issue, alternative forms of transportation have been considered in transportation planning. In this study, active transportation mode air quality was monitored on selected Woodward Park and Old Clovis trails and urban bike lanes. Real-time aerosol monitors, and low-cost sensors were carried in a backpack on bicycles during the sampling. Researchers collected GPS data via a portable GPS technology called Tracksticks. Driving transportation mode air quality data was acquired from the roadways within the Fresno/Clovis area, spanning six sampling routes, and during intercity trips between Fresno, Berkeley, and Los Angeles, for a total of five sampling routes. ‘On-Road' (outside vehicle) monitors were installed on the roof of a vehicle while ‘In-Vehicle’ monitors were installed inside the vehicle for comparison with the particulate pollution levels in the two contrasting microenvironments. The results showed the following three main outcomes: (1) clear relationships exist among PMs of different sizes; (2) there were greater variations in air quality of bike trails and On-Road samples than backyard and In-Vehicle samples; (3) we observed significant differences in air quality inside and outside the vehicle while driving local and intercity roadways; and (4) the road trip to the Bay area revealed that San Joaquin Valley has increased ambient PM2.5 and black carbon (BC) levels compared to those in the Bay Area on every trip, regardless of the daily change of the air quality.