Academic literature on the topic 'Spatial spreads'

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Journal articles on the topic "Spatial spreads"

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Dell’Erba, Salvatore, Emanuele Baldacci, and Tigran Poghosyan. "Spatial spillovers in emerging market spreads." Empirical Economics 45, no. 2 (October 26, 2012): 735–56. http://dx.doi.org/10.1007/s00181-012-0644-7.

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Dell'Erba, Salvatore, Emanuele Baldacci, and Tigran Poghosyan. "Spatial Spillovers in Emerging Market Spreads." IMF Working Papers 11, no. 221 (2011): 1. http://dx.doi.org/10.5089/9781463904234.001.

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Suksamran, Jeerawan, Yongwimon Lenbury, and Sanoe Koonprasert. "Traveling Wave Solutions of a Four Dimensional Reaction-Diffusion Model for Porcine Reproductive and Respiratory Syndrome with Time Dependent Infection Rate." Computation 9, no. 3 (March 9, 2021): 30. http://dx.doi.org/10.3390/computation9030030.

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Porcine reproductive and respiratory syndrome virus (PRRSV) causes reproductive failure in sows and respiratory disease in piglets and growing pigs. The disease rapidly spreads in swine populations, making it a serious problem causing great financial losses to the swine industry. However, past mathematical models used to describe the spread of the disease have not yielded sufficient understanding of its spatial transmission. This work has been designed to investigate a mathematical model for the spread of PRRSV considering both time and spatial dimensions as well as the observed decline in infectiousness as time progresses. Moreover, our model incorporates into the dynamics the assumption that some members of the infected population may recover from the disease and become immune. Analytical solutions are derived by using the modified extended hyperbolic tangent method with the introduction of traveling wave coordinate. We also carry out a stability and phase analysis in order to obtain a clearer understanding of how PRRSV spreads spatially through time.
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Foglia, Matteo, Alessandra Ortolano, Elisa Di Febo, and Eliana Angelini. "Bad or good neighbours: a spatial financial contagion study." Studies in Economics and Finance 37, no. 4 (September 14, 2020): 753–76. http://dx.doi.org/10.1108/sef-03-2020-0082.

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Purpose The purpose of this paper is to study the evolution of financial contagion between Eurozone banks, observing the credit default swaps (CDSs) market during the period 2009–2017. Design/methodology/approach The authors use a dynamic spatial Durbin model that enables to explore the direct and indirect effects over the short and long run and the transmission channels of the contagion. Findings The results show how contagion emerges through physical and financial market links between banks. This finding implies that a bank can fail because people expect other related financial institutions to fail as well (self-fulfilling crisis). The study provides statistically significant evidence of the presence of credit risk spillovers in CDS markets. The findings show that equity market dynamics of “neighbouring” banks are important factors in risk transmission. Originality/value The research provides a new contribution to the analysis of EZ banking risk contagion, studying CDS spread determinants both under a temporal and spatial dimension. Considering the cross-dependence of credit spreads, the study allowed to verify the non-linearity between the probability of default of a debtor and the observed credit spreads (credit spread puzzle). The authors provide information on the transmission mechanism of contagion and, on the effects among the largest banks. In fact, through the study of short- and long-term impacts, direct and indirect, the paper classify banks of systemic importance according to their effect on the financial system.
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Todorova, Zornitsa. "Network Risk in the European Sovereign CDS Market." Review of Finance and Banking 12, no. 2 (December 31, 2020): 137–54. http://dx.doi.org/10.24818/rfb.20.12.02.03.

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This paper applies novel tools from spatial econometrics to measure, quantifyand predict sovereign CDS spreads. Network risk is modelled by making each sovereignísCDS spread a function of the CDS spreads of its ìneighborsî in the Önancial network. Themain Öndings of the paper are: (1) the network model improves forecasting accuracy by 15% to 20%; (2) exogenous Önancial shocks propagate in the network of sovereigns and 40 %to 50% of the total e§ect is due to indirect (network) e§ects. These Öndings suggest analternative explanation to the well-known credit spread puzzle. To rationalize the Öndingsthe paper develops a simple structural network model of sovereign credit risk with Önancialcross-holdings and multiple equilibria.
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Kim, Taehyong, Kang Li, Aidong Zhang, Surajit Sen, and Murali Ramanathan. "A Computational Model of Mitigating Disease Spread in Spatial Networks." International Journal of Artificial Life Research 2, no. 2 (April 2011): 77–94. http://dx.doi.org/10.4018/jalr.2011040104.

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This study examines the problem of disease spreading and containment in spatial networks, where the computational model is capable of detecting disease progression to initiate processes mitigating infection spreads. This paper focuses on disease spread from a central point in a 1 x 1 unit square spatial network, and makes the model respond by trying to selectively decimate the network and thereby contain disease spread. Attention is directed on the kinematics of disease spreading with respect to how damage is controlled by the model. In addition, the authors analyze both the sensitivity of disease progression on various parameter settings and the correlation of parameters of the model. As the result, this study suggests that the radius of containment process is the most critical parameter and its best values with the computational model would be a great help to reduce damages from disease spread of a future pandemic. The study can be applied to controlling other virus spread problems in spatial networks such as disease spread in a geographical network and virus spread in a brain cell network.
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Nguyen, Thi-Quynh. "A Review of Applications of Spatial Statistics in the Study of COVID-19 Pandemic in Vietnam." International Journal of Science and Healthcare Research 8, no. 3 (July 19, 2023): 31–36. http://dx.doi.org/10.52403/ijshr.20230306.

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The spread of the 2019 novel coronavirus disease (COVID-19) in Wuhan city, China, caused by the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), spreads rapidly across the world and has negatively affected almost all countries. The Covid-19 pandemic has engulfed the world with a rapid, unexpected, and far-reaching global crisis. In the study of COVID-19 pandemic, spatial statistics have played an important role in many aspects, especially in the study of the clustering of COVID-19 pandemic. This paper summarises 24 scientific papers on applications of spatial statistics including the local Moran’s I and Getis-Ord’s statistics on studies of the COVID-19 pandemic in Vietnam. The findings of this study provide insight into not only how to apply spatial clustring in spatial statistics to analyze the clustering of the COVID-19 pandemic, but also preventing the COVID-19 spread across the world. Keywords: Applications, Spatial statistics, spatial clustering, local Moran’s I and Getis-Ord’s G statistics, the COVID-19 pandemic.
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Cornblath, Eli J., Howard L. Li, Lakshmi Changolkar, Bin Zhang, Hannah J. Brown, Ronald J. Gathagan, Modupe F. Olufemi, et al. "Computational modeling of tau pathology spread reveals patterns of regional vulnerability and the impact of a genetic risk factor." Science Advances 7, no. 24 (June 2021): eabg6677. http://dx.doi.org/10.1126/sciadv.abg6677.

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Neuropathological staging studies have suggested that tau pathology spreads through the brain in Alzheimer’s disease (AD) and other tauopathies, but it is unclear how neuroanatomical connections, spatial proximity, and regional vulnerability contribute. In this study, we seed tau pathology in the brains of nontransgenic mice with AD tau and quantify pathology development over 9 months in 134 brain regions. Network modeling of pathology progression shows that diffusion through the connectome is the best predictor of tau pathology patterns. Further, deviations from pure neuroanatomical spread are used to estimate regional vulnerability to tau pathology and identify related gene expression patterns. Last, we show that pathology spread is altered in mice harboring a mutation in leucine-rich repeat kinase 2. While tau pathology spread is still constrained by anatomical connectivity in these mice, it spreads preferentially in a retrograde direction. This study provides a framework for understanding neuropathological progression in tauopathies.
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Peromaa, T.-L., and P. I. Laurinen. "An Illusory Contour Induces Texture Segmentation." Perception 26, no. 1_suppl (August 1997): 310. http://dx.doi.org/10.1068/v970086.

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It is known that neurons in V1 can signal a contour between two out-of-phase gratings [Grosof et al, 1993 Nature (London)365 550 – 552]. We demonstrate that this type of illusory contour can segregate areas of surfaces without any luminance, contrast, or textural difference between the areas. We have studied the conditions under which the illusory contour induces texture segmentation. The target was a circular contrast-inverted area (diameter 0.22 – 8.3 deg) in the centre of an isotropic narrow-band noise texture (centre spatial frequency 0.4 – 7 cycles deg−1). Generally, segmentation was effortless in low-spatial-frequency textures but gradually disappeared with increasing spatial frequency although the contour remained visible. In a staircase experiment, the highest spatial frequency allowing segmentation was measured for each target size. The task was to tell whether the stimulus contained an object or just a contour. A negative power function relates the target diameter and the highest spatial frequency allowing segmentation. The visibility of the contour was independent of the target size. The illusory contour ‘captures’ the texture inside. However, the process is spatially limited. In a separate experiment, the subject used a cursor to point out how far from the contour the capture spreads. A negative relationship between the spatial spread and the spatial frequency of the texture was found. These findings are consistent with the idea that low-level mechanisms signalling illusory contours are involved in perceptual scene segmentation.
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Moses, Melanie E., Steven Hofmeyr, Judy L. Cannon, Akil Andrews, Rebekah Gridley, Monica Hinga, Kirtus Leyba, et al. "Spatially distributed infection increases viral load in a computational model of SARS-CoV-2 lung infection." PLOS Computational Biology 17, no. 12 (December 23, 2021): e1009735. http://dx.doi.org/10.1371/journal.pcbi.1009735.

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A key question in SARS-CoV-2 infection is why viral loads and patient outcomes vary dramatically across individuals. Because spatial-temporal dynamics of viral spread and immune response are challenging to study in vivo, we developed Spatial Immune Model of Coronavirus (SIMCoV), a scalable computational model that simulates hundreds of millions of lung cells, including respiratory epithelial cells and T cells. SIMCoV replicates viral growth dynamics observed in patients and shows how spatially dispersed infections can lead to increased viral loads. The model also shows how the timing and strength of the T cell response can affect viral persistence, oscillations, and control. By incorporating spatial interactions, SIMCoV provides a parsimonious explanation for the dramatically different viral load trajectories among patients by varying only the number of initial sites of infection and the magnitude and timing of the T cell immune response. When the branching airway structure of the lung is explicitly represented, we find that virus spreads faster than in a 2D layer of epithelial cells, but much more slowly than in an undifferentiated 3D grid or in a well-mixed differential equation model. These results illustrate how realistic, spatially explicit computational models can improve understanding of within-host dynamics of SARS-CoV-2 infection.
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Dissertations / Theses on the topic "Spatial spreads"

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Lindström, Tom. "Spatial Spread of Organisms : Modeling ecological and epidemiological processes." Doctoral thesis, Linköpings universitet, Teoretisk Biologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-54839.

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This thesis focuses on the spread of organisms in both ecological and epidemiological contexts. In most of the studies presented, displacement is modeled with a spatial kernel function, which is characterized by scale and shape. These are measured by the net squared displacement (or kernel variance) and kurtosis, respectively. If organisms disperse by the assumptions of a random walk or correlated random walk, a Gaussian shaped kernel is expected. Empirical studies often report deviations from this, and commonly leptokurtic distributions are found, often as a result of heterogeneity in the dispersal process. In the studies presented in two of the included papers, the importance of the kernel shape is tested, by using a family of kernels where the shape and scale can be separated effectively. Both studies utilize spectral density approaches for modeling the spatial environment. It is concluded that the shape is not important when studying the population distribution in a habitat/matrix context. The shape is however important when looking at the invasion of organisms in a patchy environment, when the arrangement of patches deviates from randomly distributed. The introduced method for generating patch distribution is also compared to empirical distributions of patches (farms and old trees). Here it is concluded that the assumptions used for modeling of the spatial environment are consistent with the observed patterns. These assumptions include fractal properties such that the same aggregational patterns are found at different scales. In a series of papers, movements of animals are considered as vectors for between-herd disease spread. The studies are based on data found in databases held by the Swedish Board of Agricultural (SJV), consisting of reported movements, as well as farm location and characteristics. The first study focuses on the distance related probability of contacts between herds. In the following papers, the analysis is expanded to include production type and herd size. Movement data of pigs (and cattle in Paper I) are analyzed with Bayesian models, implemented with Markov Chain Monte Carlo (MCMC). This is a flexible approach that allows for parameter estimations of complex models, and at the same time includes parameter uncertainty. In Paper IV, the effects of the included factors are investigated. It is shown that all three factors (herd size, production type structure and distance related probability of contacts) are expected to influence disease spread dynamics, however the production type structure is found to be the most important factor. This emphasizes the value of keeping such information in central databases. The models presented can be used as support for risk analysis and disease tracing. However, data reliability is always a problem, and implementation may be improved with better quality data. The thesis also shows that utilizing spatial kernels for description of the spatial spread of organisms is an appropriate approach. However, these kernels must be flexible and flawed assumptions about the shape may lead to erroneous conclusions. Hence, the joint distribution of kernel shape and scale should be estimated. The flexibility of Bayesian analysis, implemented with MCMC techniques, is a good approach for this, and further allows for implementation of more complex models where other factors may be included.
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Vernon, Matthew Christopher. "Spatial spread of farm animal diseases." Thesis, University of Cambridge, 2010. https://www.repository.cam.ac.uk/handle/1810/240490.

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Data on cattle movements within the United Kingdom have recently become available. As part of the conditions for lifting an export ban on British beef following the bovine spongiform encephalopathy epidemic, the European Union required that the UK should have 'An effective animal identification and movement recording system'. The Cattle Tracing System (CTS) was introduced in September 1998, and the scheme was extended to include all cattle by the beginning of 2001. Contact networks have proved valuable in studying the epidemiology of diseases in man, such as human immunodeficiency virus; the availability of CTS cattle movement data has enabled contact network analysis to be applied to diseases of farm livestock. The CTS data may be represented as a large network; cattle holdings are represented as nodes, with a movement of cattle between holdings being an edge. To address concerns about the quality of this cattle movement data, a field study was conducted on Lewis, one of the Western Isles of Scotland. Farmers were recruited with the assistance of the local veterinary surgeon, and asked to record a range of potential risk behaviours relating to the transmission of infectious diseases (moving livestock, sharing pasture, etc.) for a one-month period. For the study area in question, movements of cattle not reported to CTS (especially to or from common grazing land) were a substantial contribution to the contact network during the study period. A wide range of measures of network structure exist, but their relevance to the dynamics of infectious diseases on networks is unclear. To address this, a discrete-time stochastic SIR simulation model of disease on a network was designed and implemented in software. Using this simulation model, a network model with the key structural features of the CTS contact network was constructed, by considering a range of measures of network structure, and testing resulting model networks against CTS-derived networks. The resulting model was shown to predict the dynamics of a simulated disease model on that contact network more closely than existing models of global network structure. Much work on the contact structure of the UK cattle herd has relied on relatively simple static network representations of movement data. By using simulated diseases, the serious shortcomings of static network representations compared to more complex dynamic network representations were demonstrated. A substantial library of software for the generation and analysis of large networks, and the simulation of disease thereupon, has been produced, and has been made generallyavailable. The design and implementation of this software is discussed, including the algorithms and data structures deployed, as well as validation of the software, and its portability to different computing platforms.
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Janarthanan, Sivarjalingam. "Spatial spread in general branching processes." Thesis, University of Sheffield, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265577.

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Bastani, Hamed [Verfasser]. "Spatial Positioning with Wireless Chirp Spread Spectrum Ranging / Hamed Bastani." Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2010. http://d-nb.info/1034989510/34.

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Ball, George LeRoy. "A spatial dynamic approach to ecological modeling: Simulating fire spread." Diss., The University of Arizona, 1990. http://hdl.handle.net/10150/184986.

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The objective of this dissertation is to develop a new research tool, PROMAP, which will allow the construction of models that satisfy the requirement of spatial distribution and hierarchical interactions within a dynamic framework. An analysis of the form of ecosystems is followed by an examination of current attempts at ecosystem modeling using spatial relationships. An examination of the analytical procedures used in the spatial modeling process, results in a set of criteria that a suitable modeling system should incorporate. These criteria are: the use of real numbers; iterative processing; flexible data retrieval; and neighborhood analytical procedures. The basic configuration of PROMAP is discussed with an emphasis on the mathematical procedures and the capability for designing cellular automata within the system. The representation of biophysical systems into a set of spatial transition functions is described in relation to the development of nested hierarchies called Q-morphisms. Having established the design of PROMAP, a suitable test is devised using the simulation of surface fire spread. A model called FIREMAP is developed and the results are compared to expected fire shapes under Zero State Conditions. These conditions are defined as uniform fuel, zero slope and zero wind with additional factors held constant. Other simulations of fire spread are made by relaxing the conditions to achieve wind driven fires and the response to potential impediments to fire spread. The response of the simulation shows an accurate correspondence between the simulation and the expected fire shape. As a final test of the model, all restrictions are removed and a simulation is made under actual conditions of complex terrain, and non-uniform fuels using data collected on the San Carlos Apache Indian Reservation in southeast Arizona. Deficiencies of PROMAP and FIREMAP are discussed as well as future implications for the FIREMAP model as a management tool.
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Yassi, Hocine. "Finite element model for the two dimensional spatial spread of rabies." Thesis, Bangor University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318087.

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Hollingsworth, Teresa Déirdre. "A theoretical framework for the spatial spread of soil-borne fungal plant pathogens." Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604173.

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The spread of mycelia through soil is the main process by which many economically important plant pathogens are transmitted between plants. Using mathematical modelling, this thesis provides a framework for investigating the interaction between soil structure and fungal growth, with a view to controlling this spread. Fungal dynamics are modelled at the scale of groups of hyphae by a stochastic cellular automaton (CA), with the cells of the CA corresponding to the network of pore species in the soil. The fungal model captures the characteristics of mycelial growth at this scale, whilst maintaining a level of mathematical tractability. The growth of mycelial fungi within and between patches is modelled by the rates of growth and quiescence, or transition to inactivity, together with structural parameters. The fungal model is analysed to identify key characteristics of the pore network which affect the morphology of the fungal colony. The soil-pore network is modelled as part of the entire soil structure. The pore space is abstracted to a network of connected patches of different sizes. The size and connections between these patches are converted into carrying capacities for hyphal colonisation and the level of connection between cells for subsequent implementation of the fungal model. The models are used to give insight on experimental data for soils of different bulk densities. The application of the soil and fungal models to this data allows the three-dimensional structure of the soils to be studied, and changes in the three-dimensional connectivity which contribute to changing hyphal density are identified. The results show that at low bulk densities there are few large, pore spaces with connections to distant pore spaces. This structure results in large sparse colonies. At high bulk densities, the pore space is made up of many smaller pore spaces which are connected to a few close pores. This structure results in small, dense colonies.
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Smith, James Martin Derek. "Modelling the spatial spread of Japanese knotweed (Fallopia japonica) in the United Kingdom." Thesis, Loughborough University, 2006. https://dspace.lboro.ac.uk/2134/33778.

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Fallopia japonica (Houtt. Ronse Decraene) (syn. Reynoutria japonica syn. Polygonum cuspidatum, Japanese knotweed) is an aggressively invasive alien weed in the United Kingdom (UK) and throughout its introduced range. Its presence can herald considerable costs, both in terms of its ecological impact as a threat to biodiversity and economically due to the physical damage caused to property and the associated costs of treatment and disposal of the plant. There is therefore increasing interest in eradicating this alien species and as a result many different management techniques have been applied to try and control its spread. It is important to ascertain which of these are most appropriate in any given situation and so tools that can test the impact and efficiency of these techniques both quickly and cheaply would be extremely useful. In this thesis mathematical models are developed for the spatial spread of F. japonica on a local scale in the UK.
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Churakov, Mikhail. "Spatial and network aspects of the spread of infectious diseases in livestock populations." Thesis, University of Glasgow, 2014. http://theses.gla.ac.uk/6417/.

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In this thesis, I focus on methodological concepts of studying infectious disease transmission between agricultural premises. I used different disease systems as exemplars for spatial and network methods to investigate transmission patterns. Infectious diseases cause tangible economic threat to the farming industry worldwide by damaging livestock populations, reducing farm productivity and causing trade restriction. This implies the importance of veterinary epidemiological studies in control and eradication of pathogens. Recent increase in availability of data and computational power allowed for more opportunities to study mechanisms of pathogenic transmission. Nowadays, the bottleneck is primarily associated with efficient methods that can analyse vast amounts of high-resolution data. Here I address two livestock pathogens that differ in their epidemiology: bacteria Streptococcus agalactiae and foot-and-mouth disease (FMD) virus. Streptococcus agalactiae is a contagious pathogen that causes mastitis in cattle, and thus possesses a substantial economic burden to the dairy industry. Known transmission routes between cattle are restricted to those via milking machines, milkers’ hands and fomites during milking process. Additionally, recent studies suggested potential introductions from other host species: primarily, humans. However, strain typing data showed discrepancies in strain compositions of bacteria isolated from humans and bovines. In this thesis, strain-specific features of between-herd transmission of Streptococcus agalactiae within dairy cattle population in Denmark are investigated. Foot-and-mouth disease (FMD) is a viral infection that affects cloven-hoofed animals and is of big importance mainly because of the trade restrictions against infected regions and countries. Control programmes against FMD usually include vaccination and culling of animals. However, the debate on the optimal control for FMD is still ongoing. In this thesis, I address questions on identification of the routes of infection and on requirements for movement recording systems to be used for efficient contact tracing during an FMD outbreak. This thesis reveals several interesting findings. Firstly, the increased understanding of strain-specific transmission characteristics of Streptococcus agalactiae. One of the observed strains (ST103) showed significant and consistent spatial clustering of its cases among Danish dairy cattle herds in 2009–2011. Secondly, the network analysis of cattle movements and affiliations with veterinary practices showed that veterinary practices were exclusively associated with transmission of ST103 of Streptococcus agalactiae. Contrastingly, movement networks appeared to be important for all the three predominant bacterial strains (ST1, ST23 and ST103). Fourthly, the new extended approach that allows estimation of the whole transmission tree at once was proposed and tested for the Darlington cluster within the 2001 FMD UK epidemic. Finally, in chapter 6, it was shown that mathematical modelling did not suggest any advantages of ensuring smaller delays in the post-silent control of FMD-like pathogens.
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Skog, Lars. "Spatial Analysis and Modeling for Health Applications." Doctoral thesis, KTH, Geodesi och geoinformatik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-142835.

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Despite the benefits of applying methods of geographic information science (GIScience), the use of such methods in health service planning and provision remains greatly underutilized. Spread of epidemic diseases is a constant threat to mankind and the globalization of the world increases the risk for global attacks from multi-resistant bacteria or deadly virus strains. Therefore, research is needed to better understand how GIScience could be used in epidemiologic analyses and other health applications. This thesis is divided into two parts; one for epidemiologic analyses and one for neighbourhood studies. The overall objective of the epidemiologic part of this research is to understand more about the spatial spread of past pandemics and to find out if there are any common patterns. This overall objective is divided into four specific research objectives; 1) to describe the spatial spread of the Russian Influenza in Sweden, 2) to create models of propagation of the Black Death in Sweden, 3) to establish spatiotemporal characteristics common to past pandemics in Sweden and 4) to visualize the spatiotemporal occurrence of salmonella among animal herds in Sweden. This thesis also discusses some other aspects of health related to place. Are differences in neighbourhood deprivation related to the amount of presence of goods and services? Is the way cities are planned affecting the behaviour within the local population regarding spontaneous walking and physical activity? The specific research objectives for this part are to define how deprivation is related to presence of goods and services in Sweden and to create walkability indices over the city of Stockholm including a quality test of these indices. Case data reported by physicians were used for the epidemiologic studies. The pandemics discussed covered the entire world, but our data is from Sweden only and as regards the Black Death there was no case data at all. The data for the goods and services analyses are from all of Sweden, whereas the walkability indices are based on data from the city of Stockholm. Various methods have been used to clean, structure and geocode the data, including hand written reports on case data, maps of poor geometric quality, information from databases on climate, demography, diseases, goods and services, income data and more, to make this data feasible for spatial analysis, modeling and visualization. Network analysis was used to model food transports in the 14th century as well as walking in the city of Stockholm today. Proximity analysis was used to assess the spatio-temporal spread of the Russian Influenza. The impact of climatological factors on the propagation of the Asian Influenza was analyzed and geographically weighted mean (GWM) calculations were used to discover common characteristics in the spatio-temporal spread of three past pandemics. Among the results generated in the epidemiologic study the following should be noted in particular; the local peaking periods of the Asian Influenza were preceded by falling temperature, the total peaking period for the three pandemics (Russian, Asian and A(H1N1)pdm09) was approximately 10 weeks and their weekly GWM followed a path from southwest to northeast (opposite direction for the A(H1N1)pdm09). From the neighborhood studies one can note that compared to the results measured and reported by tested individuals there is a positive (small but significant) association between neighborhood walkability and physical activity outcomes. The main contribution of this work is that it gives epidemiologists and public health specialists new ideas, not only on how to formulate, model, analyze and visualize different health related research questions but also ideas on how new procedures could be implemented in their daily work. Once the data reporting is organized in a suitable manner there is a multitude of options on how to present important and critical information to officials and policy makers.

QC 20140313

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Books on the topic "Spatial spreads"

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H, Peterson Seth, ed. Using HFire for spatial modeling of fire in shrublands. Albany, CA: United States Dept. of Agriculture, Forest Service, Pacific Southwest Research Station, 2009.

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H, Peterson Seth, ed. Using HFire for spatial modeling of fire in shrublands. Albany, CA: United States Dept. of Agriculture, Forest Service, Pacific Southwest Research Station, 2009.

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Puga, Diego. The spread of industry: Spatial agglomeration in economic development. London: Centre for Economic Policy Research, 1996.

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Puga, Diego. The spread of industry: Spatial agglomeration in economic development. London: London School of Economics, Centre for Economic Performance, 1996.

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Batty, Michael. The spatial impact of computer culture: An essay on post-industrialism and the spread of the personal computer. Cardiff: UWIST. Dept. of Town Planning, 1985.

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Cliff, A. D. The spread of measles in Fiji and the Pacific: Spatial components in the transmission of epidemic waves through island communities. Canberra: Research School of Pacific Studies, Australian National University, 1985.

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The spatial analysis of radiocarbon databases: The spread of the first farmers in Europe and of the fat-tailed sheep in Southern Africa. Oxford, England: Archaeopress, 2004.

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van Berkel, Klaas, and Ernst Homburg. The Laboratory Revolution and the Creation of the Modern University, 1830-1940. Nieuwe Prinsengracht 89 1018 VR Amsterdam Nederland: Amsterdam University Press, 2023. http://dx.doi.org/10.5117/9789463720434.

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The modern research university originated in Europe in the second half of the nineteenth century, largely due to the creation and expansion of the teaching and research laboratory. The universities and the sciences underwent a laboratory revolution that fundamentally changed the nature of both. This revolutionary development began in chemistry, where Justus Liebig is credited with systematically employing his students in his ongoing research during the 1830s. Later, this development spread to other fields, including the social sciences and the humanities. The consequences for the universities were colossal. The expansion of the laboratories demanded extensive new building programs, reshaping the outlook of the university. The social structure of the university also diversified because of this laboratory expansion, while what it meant to be a scientist changed dramatically. This volume explores the spatial, social, and cultural dimensions of the rise of the modern research laboratory within universities and their consequent reshaping.
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Poghosyan, Tigran, Salvatore Dell'Erba, and Emanuele Baldacci. Spatial Spillovers in Emerging Market Spreads. International Monetary Fund, 2011.

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Poghosyan, Tigran, Salvatore Dell'Erba, and Emanuele Baldacci. Spatial Spillovers in Emerging Market Spreads. International Monetary Fund, 2011.

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Book chapters on the topic "Spatial spreads"

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Bryan, Dick, Michael Rafferty, and Duncan Wigan. "From Time-Space Compression to Spatial Spreads." In Money and Finance After the Crisis, 41–67. Chichester, UK: John Wiley & Sons, Ltd, 2017. http://dx.doi.org/10.1002/9781119051374.ch2.

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Hassan, Amer A., John E. Hershey, and Gary J. Saulnier. "Spatial Optical CDMA." In Perspectives in Spread Spectrum, 107–25. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-5531-5_5.

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Brus, Dick J. "Balanced and well-spread sampling." In Spatial Sampling with R, 137–60. Boca Raton: Chapman and Hall/CRC, 2022. http://dx.doi.org/10.1201/9781003258940-9.

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Rosenkranz, Gerd. "Stochastic measure diffusions as models of growth and spread." In Stochastic Spatial Processes, 238–48. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/bfb0076252.

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Iannelli, Mimmo, and Andrea Pugliese. "Spatial spread of a population." In UNITEXT, 113–42. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-03026-5_5.

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Lutscher, Frithjof. "The Shape of Spatial Spread." In Interdisciplinary Applied Mathematics, 145–59. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-29294-2_11.

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Lutscher, Frithjof. "The Speed of Spatial Spread." In Interdisciplinary Applied Mathematics, 53–73. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-29294-2_5.

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Lutscher, Frithjof. "Spatial Spread with Allee Effect." In Interdisciplinary Applied Mathematics, 75–86. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-29294-2_6.

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Malik, R., and T. P. Yew. "Reduced Feedback Closed-Loop Spatial Multiplexing for B3G Systems." In Multi-Carrier Spread-Spectrum, 267–74. Dordrecht: Springer Netherlands, 2006. http://dx.doi.org/10.1007/1-4020-4437-2_28.

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Fortin, Marie-Josée, Mark R. T. Dale, and Stefania Bertazzon. "Spatial Analysis of Wildlife Distribution and Disease Spread." In Spatial Complexity, Informatics, and Wildlife Conservation, 255–72. Tokyo: Springer Japan, 2010. http://dx.doi.org/10.1007/978-4-431-87771-4_15.

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Conference papers on the topic "Spatial spreads"

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Turano, Kathleen. "Bisection Accuracy and Precision in Patients with Retinitis Pigmentosa." In Noninvasive Assessment of the Visual System. Washington, D.C.: Optica Publishing Group, 1990. http://dx.doi.org/10.1364/navs.1990.wa2.

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Retinitis pigmentosa (RP) is a pigmentary retinal degeneration that is typically characterized by profound nightblindness and progressive visual field loss. Visual field loss typically begins in the midperiphery as a ring scotoma and spreads both centrally and to the far periphery, resulting in severely contracted fields that often are characterized as "tunnel vision". Visual acuity typically remains 20/40 or better until the most advanced stages of the disease. Although RP has been characterized clinically, little is known about the spatial sense of the RP eye. For example, how accurate and precise are spatial position judgments when the visual targets are within the remaining parts of the patient’s visual field?
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Murugan, Raju, Dhanalakshmi Sellan, and Pankaj S. Kolhe. "Experimental Study of Flow Field Effect on Spray and Flame Structure in Swirl Stabilized Combustor." In ASME 2019 Gas Turbine India Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gtindia2019-2639.

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Abstract The spatial distribution of spray plays a key role in liquid fuel combustion, which dictates the local mixture fraction and the flame temperature distribution in gas turbine engines. The swirling flow creates further decomposition of the spray droplets in liquid fuel gas turbine engine, which increases the surface area of the droplets. Turbulent mixing due to the swirling flow is essential for preheating of unburned products and flame holding in the combustor. A lab-scale swirl stabilized liquid fuel combustor was designed and fabricated with the geometric swirl number (SN) of 1. Combustor flow geometry involves internal spray from flow blurring twin-fluid atomizer, surrounded by swirling airflow which is confined with co-flow air to provide full optical access. At constant spray operating conditions, the swirl Reynolds number (Re) is increased whereas co-flow velocity was maintained constant at 0.4 m/s. An experimental study was carried out to understand the effect of Reynolds number on the aerodynamic structure of airflow, the spatial distribution of spray structure and kerosene flame structures using Particle Image Velocimetry (PIV) and direct imaging. The experimental results show that the flow structure and spray spreads radially with the increase in swirl Reynolds number and the corresponding core spray height decreases, which were evident from flame images.
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Georgiou, Ioannis T., and Nikolaos Kintzios. "Discovering Irregular Diagnostic Proper Orthogonal Decomposition Signatures in Healthy Marine Ball Bearings." In ASME 2012 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/imece2012-89173.

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Presented is a structural health condition diagnosis based on optimal space-time decompositions of ensembles of acceleration signals developed in the complex physical domain of marine ball bearings when interrogated by a set of diagnostic impulsive forces. Ensembles of diagnostic forces and ensembles of collocated responses acceleration signals are decomposed into proper orthogonal modes. Typical inner and ensembles of nondestructive impact diagnostic forces covering three times the inner and outer races are strongly dominated by a single POD mode with uniform spatial distribution and a sharp pulse time modulation. There exist high order modes with very small amount of energy. This indicates that the impact response of the suspended ball bearing depends slightly on the impact location. Diametrically opposite, the typical ensemble of radial acceleration signals collected at a point on the outer race has a very broad POD energy spectrum. All POD modes have energy fractions of the same order and irregular (no periodic) space modulations. Despite this spatial irregularity, all POD spatial modulations have astonishingly common statistical properties: nearly zero mean values, and nearly identical standard deviations at the value level of the uniform spatial distribution of the dominant POD mode of the ensembles of diagnostic forces. The result is that the healthy ball bearing spreads nearly evenly the energy of collocated acceleration signals to a large number of POD modes. The analysis aims at gaining a basic understanding of the behavior of collocated acceleration signals developed in the complex domains of multi-body flexible structures with applications in structural health monitoring of marine-aeronautical machinery critical elements such as propellers, bearings, brakes, clutches and gearboxes.
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Fuchiwaki, Masaki. "Vorticity Growth Formed in Vicinity of a Wall on a Moving Elastic Airfoil." In ASME 2021 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/fedsm2021-65513.

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Abstract The flow field around moving airfoils capable of flexible elastic deformation has become a focus of attention. These flow fields may be understood as a fluid-structure interaction (FSI) problem, and the motion and deformation of elastic airfoils, as well as the associated vortex flow phenomena in their vicinity, are complicated. Many studies on the flow filed around the elastic moving airfoil have been investigated by experimental and numerical approached. The macro scale vortex structure and the dynamic forces acting on the elastic moving airfoil have been understood. However, the growth process of the vorticity in a vicinity of the wall of an elastic airfoil has not been clarified sufficiently. In this study, the authors focus on the dynamic behaviors of vorticity in the vicinity of the wall on the elastic heaving airfoil and investigate the growth process of the vorticity in a vicinity of the wall of an elastic airfoil by the fluid structure interaction and LES simulations using ANSYS 17.0/ANSYS CFX 17.0. The vorticity in the vicinity of a wall of the elastic airfoil spreads along the wall simultaneously with the increase of the spatial gradient of the wall, and discrete vorticity regions coalesce into a single layer. The time variation in spatial gradient contribute greatly to the growth and development of vorticity.
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Qiu, Wenxun, Xiaochun Gong, and Guodong Xu. "Real-time performance validation of spread spectrum aloha for satellite formation flying." In Second International Conference on Spatial Information Technology, edited by Cheng Wang, Shan Zhong, and Jiaolong Wei. SPIE, 2007. http://dx.doi.org/10.1117/12.772974.

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Li, Y., and J. P. Longtin. "Optical Technique to Measure Transient Interface Temperature During Droplet Impingement on a Cooled Surface." In ASME 2000 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/imece2000-1393.

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Abstract Liquid droplets impinging upon a solid surface are present in many diverse and important engineering and scientific applications. Examples include impingement cooling of surfaces, condensation phenomena in which liquid droplets fall and strike a surface, vigorous mixing of gas-liquid systems, and in manufacturing, e.g., pouring a liquid material onto a cooled surface or mold to form objects. The accurate measurement of the solid-liquid interface temperature of a liquid droplet impinging on a solid surface is extremely difficult to do using traditional, contact-based techniques, however. This work presents a laser-based technique that is capable of resolving the transient interface temperature change as a liquid droplet strikes a surface. The measurement records changes in reflected light from the liquid-solid interface, which is correlated to temperature change. In this work, the substrate is BK7 glass or quartz. The liquid falls from a height of several centimeters, while the laser beam is sent through the transparent solid material from the underside for the measurement. Results are presented for water and glycerin, with good agreement found between predicted and measured temperature histories. Additional features of the technique include extremely fast temporal resolution, which is limited only by the speed of the light-capturing electronics. A temporal resolution of 1 microsecond is readily obtainable with inexpensive electronics. Also, the use of a high-quality Gaussian laser beam from, e.g., a HeNe laser or a single-mode fiber can be focused to a spot size ranging from several millimeters to 10 microns in diameter at the liquid interface, thus providing a wide variety of spatial resolutions, including those in the microscale. Finally, an array of interrogation beams can be employed simultaneously to monitor the spatial temperature history of a droplet as it spreads and cools once striking the surface. Both present and future applications of the technique will be discussed in the talk.
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Takeishi, K., M. Komiyama, Y. Oda, Y. Egawa, and T. Kitamura. "Aerothermal Investigations on Mixing Flow Field of Film Cooling With Swirling Coolant Flow." In ASME 2011 Turbo Expo: Turbine Technical Conference and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/gt2011-46838.

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This paper describes the experimental results of a new film cooling method blowing through circular and shaped film cooling holes with swirling coolant flow. The experiments have been conducted by using a scale-up model of a film cooling hole installed on the bottom surface of a low-speed wind tunnel. Swirling motion of film coolant was induced inside a hexagonal plenum by two slant impingement jets, which are inclined at α degree toward the vertical direction and installed in a staggered position. The two impingement jets generate swirling flows inside the plenum, and this swirling flow enters into a film cooling hole keeping the angular momentum until the exit of the film cooling hole. The slant angle of the impingement jets was changed as α = 0°, 10°, 20°, 30° in their wind tunnel tests. The film cooling effectiveness on the flat wall was measured by using pressure sensitive paint (PSP) technique. In addition, the spatial distribution of non-dimensional concentration (or temperature) and flow field were measured by laser induced fluorescence (LIF) and particle image velocimetry (PIV), respectively. In case of the circular film cooling hole, the coolant jet penetration into mainstream is suppressed by swirling motion of the coolant. As a result, though the coolant jet is deflected in the pitch direction, the film cooling effectiveness distribution on the wall keeps higher value behind the cooling hole over a long range. Additionally, kidney vortex structure disappeared. For the shaped cooling hole, the coolant jet spreads wider in spanwise direction at the downstream. Thus, the pitch averaged film cooling effectiveness at the downstream was 50% higher than that of the non-swirling case.
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Luo, Zezhou, Bin Ye, and Lier Bao. "On the performance of multicarrier direct sequence spread spectrum with band-limited Gaussian interference and multipath fading." In Second International Conference on Spatial Information Technology, edited by Cheng Wang, Shan Zhong, and Jiaolong Wei. SPIE, 2007. http://dx.doi.org/10.1117/12.774836.

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Rimjhim and Sourav Dandapat. "Predicting Spatial Spread on Social Media." In WWW '22: The ACM Web Conference 2022. New York, NY, USA: ACM, 2022. http://dx.doi.org/10.1145/3487553.3524646.

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Casalone, Pietro, Oronzo dell’Edera, Marco Fontana, Giuliana Mattiazzo, and Beatrice Battisti. "Solutions to Wave Damping Over Time in CFD RANS Simulations Due to Exponential Generation of Numerical Turbulence." In ASME 2022 41st International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/omae2022-81447.

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Abstract In ocean engineering, high-fidelity analyses like computational fluid dynamics Unsteady Reynolds Averaged Navier Stokes simulations are fundamental for the evaluation of realistic hydrodynamic loads during extreme events, which are usually overestimated by boundary element method based solvers, thus leading to the definition of an oversized wave energy converter structure. To describe multiphase flows, the most used model in RANS CFD simulations is Volume of Fluid model, which consists in creating an interface between the different fluids and assigning to each cell of the domain a percentage of each phase. Unfortunately, the model has a well-known problem in the ocean engineering community which increases with simulation time and affects the wave propagation. For the correct spatial propagation of the wave motion, it is necessary to use a very low Courant-Friedrich-Lewy factor, hence causing a noticeable increase in the computational time and speeding up the generation of artificial turbulence in the domain. The problem is intrinsic in the Volume of Fluid model and cannot be solved by refining the mesh or increasing the order of accuracy of the solvers. The numerical turbulence spreads in the whole domain and dampens the waves overtime after several wave periods (10–50). With this work, we analyse the effect of a threshold on the turbulent viscosity to reduce the production of numerical turbulent kinetic energy; theaim is to produce a general methodology to simulate long time frames in a RANS simulation with the Volume of Fluid model. The investigation is first performed in a semi-2D tank by monitoring the wave probes over time. It is then repeated in a 3D domainwith and without the limiter in the case of a floating body, to verify that the kinematics of the floater is not altered by the limiter.
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Reports on the topic "Spatial spreads"

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Lylo, Taras. Ideologemes of modern Russian propaganda in Mikhail Epstein’s essayistic interpretations. Ivan Franko National University of Lviv, February 2022. http://dx.doi.org/10.30970/vjo.2022.51.11404.

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The article analyzes the main anti-propaganda accents in Mikhail Epstein’s essayistic argumentation about such messages of modern Russian propaganda as “Russia is threatened by an external enemy”, “Russia is a significant, powerful country”, “The collapse of the USSR was a tragedy”, “Russia is a special spiritual civilization”, “Our cause in Donbass is sacred”, “The enemy uses, or may use of illegal weapons”... A special emphasis is placed on the fact that the basis of these concepts is primarily ontological rather than ideological. Ideology is rather a cover for problematic Russian existence as a consequence of Russia’s problematic identity and for its inability to find itself in history. As a result, Russia is trying to resolve its historical issues geographically, through spatial expansion, trying to implement ideologemes such as “The Great Victory. We can repeat” or “Novorossia”. That is why M. Epstein clearly identifies the national and psychological basis of the Kremlin’s behavior in 2014-2021. М. Epstein easily refutes the main ideologemes of Russian propaganda. This gives grounds to claim that Russian political technologists use the classical principles of propaganda: ignore people who think; if the addressee is the masses, focus on a few simple points; reduce each problem to the lowest common denominator that the least educated person can repeat and remember; be guided by historical realities that appeal to well-known events and symbols and appeal to emotions, not to the mind. М. Epstein’s argumentation clearly points to another feature of modern Russian propaganda: if Soviet propaganda was concerned with the plausibility of its lies, then Kremlin propaganda does not care at all. It totally spreads lies, often ignoring even attempts to offer half-truth.
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Huntley, D., D. Rotheram-Clarke, R. Cocking, J. Joseph, and P. Bobrowsky. Current research on slow-moving landslides in the Thompson River valley, British Columbia (IMOU 5170 annual report). Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/331175.

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Interdepartmental Memorandum of Understanding (IMOU) 5170 between Natural Resources Canada (NRCAN), the Geological Survey of Canada (GSC) and Transport Canada Innovation Centre (TC-IC) aims to gain new insight into slow-moving landslides, and the influence of climate change, through testing conventional and emerging monitoring technologies. IMOU 5107 focuses on strategically important sections of the national railway network in the Thompson River valley, British Columbia (BC), and the Assiniboine River valley along the borders of Manitoba (MN) and Saskatchewan (SK). Results of this research are applicable elsewhere in Canada (e.g., the urban-rural-industrial landscapes of the Okanagan Valley, BC), and around the world where slow-moving landslides and climate change are adversely affecting critical socio-economic infrastructure. Open File 8931 outlines landslide mapping and changedetection monitoring protocols based on the successes of IMOU 5170 and ICL-IPL Project 202 in BC. In this region, ice sheets, glaciers, permafrost, rivers and oceans, high relief, and biogeoclimatic characteristics contribute to produce distinctive rapid and slow-moving landslide assemblages that have the potential to impact railway infrastructure and operations. Bedrock and drift-covered slopes along the transportation corridors are prone to mass wasting when favourable conditions exist. In high-relief mountainous areas, rapidly moving landslides include rock and debris avalanches, rock and debris falls, debris flows and torrents, and lahars. In areas with moderate to low relief, rapid to slow mass movements include rockslides and slumps, debris or earth slides and slumps, and earth flows. Slow-moving landslides include rock glaciers, rock and soil creep, solifluction, and lateral spreads in bedrock and surficial deposits. Research efforts lead to a better understanding of how geological conditions, extreme weather events and climate change influence landslide activity along the national railway corridor. Combining field-based landslide investigation with multi-year geospatial and in-situ time-series monitoring leads to a more resilient railway national transportation network able to meet Canada's future socioeconomic needs, while ensuring protection of the environment and resource-based communities from landslides related to extreme weather events and climate change. InSAR only measures displacement in the east-west orientation, whereas UAV and RTK-GNSS change-detection surveys capture full displacement vectors. RTK-GNSS do not provide spatial coverage, whereas InSAR and UAV surveys do. In addition, InSAR and UAV photogrammetry cannot map underwater, whereas boat-mounted bathymetric surveys reveal information on channel morphology and riverbed composition. Remote sensing datasets, consolidated in a geographic information system, capture the spatial relationships between landslide distribution and specific terrain features, at-risk infrastructure, and the environmental conditions expected to correlate with landslide incidence and magnitude. Reliable real-time monitoring solutions for critical railway infrastructure (e.g., ballast, tracks, retaining walls, tunnels, and bridges) able to withstand the harsh environmental conditions of Canada are highlighted. The provision of fundamental geoscience and baseline geospatial monitoring allows stakeholders to develop robust risk tolerance, remediation, and mitigation strategies to maintain the resilience and accessibility of critical transportation infrastructure, while also protecting the natural environment, community stakeholders, and Canadian economy. We propose a best-practice solution involving three levels of investigation to describe the form and function of the wide range of rapid and slow-moving landslides occurring across Canada that is also applicable elsewhere. Research activities for 2022 to 2025 are presented by way of conclusion.
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Haeckel, Matthias, and Peter Linke. RV SONNE Fahrtbericht/Cruise Report SO268 - Assessing the Impacts of Nodule Mining on the Deep-sea Environment: NoduleMonitoring, Manzanillo (Mexico) – Vancouver (Canada), 17.02. – 27.05.2019. GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel, November 2021. http://dx.doi.org/10.3289/geomar_rep_ns_59_20.

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Cruise SO268 is fully integrated into the second phase of the European collaborative JPI-Oceans project MiningImpact and is designed to assess the environmental impacts of deep-sea mining of polymetallic nodules in the Clarion-Clipperton Fracture Zone (CCZ). In particular, the cruise aimed at conducting an independent scientific monitoring of the first industrial test of a pre-protoype nodule collector by the Belgian company DEME-GSR. The work includes collecting the required baseline data in the designated trial and reference sites in the Belgian and German contract areas, a quantification of the spatial and temporal spread of the produced sediment plume during the trials as well as a first assessment of the generated environmental impacts. However, during SO268 Leg 1 DEME-GSR informed us that the collector trials would not take place as scheduled due to unresolvable technical problems. Thus, we adjusted our work plan accordingly by implementing our backup plan. This involved conducting a small-scale sediment plume experiment with a small chain dredge to quantify the spatial and temporal dispersal of the suspended sediment particles, their concentration in the plume as well as the spatial footprint and thickness of the deposited sediment blanket on the seabed.
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Van Winkle, Jill. Informal Trails and the Spread of Invasive Species in Urban Natural Areas: Spatial Analysis of Informal Trails and their Effects on Understory Plant Communities in Forest Park, Portland, Oregon. Portland State University Library, January 2000. http://dx.doi.org/10.15760/etd.1840.

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Du, Xinming, Elaine S. Tan, Yesim Elhan-Kayalar, and Yasuyuki Sawada. Economic Impact of COVID-19 Containment Policies: Evidence Based on Novel Surface Heat Data from the People’s Republic of China. Asian Development Bank, October 2022. http://dx.doi.org/10.22617/wps220243-2.

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This paper uses spatially granular surface urban heat island (SUHI) data to quantify the impact of COVID-19-related containment policies on economic output in the People’s Republic of China (PRC). Governments have adopted various policies and measures to control the spread of coronavirus disease (COVID-19). Results of the study suggest containment measures in the PRC decreased SUHI in locked cities marginally yet generated positive and negative spillover effects in unlocked cities, with positive effects dominating. The paper also notes that initial experiences helped inform the management of containment measures in the country.
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Chauvin, Juan Pablo. Cities and Public Health in Latin America. Inter-American Development Bank, October 2021. http://dx.doi.org/10.18235/0003692.

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This paper presents an overview of how health outcomes vary across cities in Latin America and discusses some of the known drivers of this variation. There are large disparities in outcomes across cities and across neighborhoods of the same city. Because health is closely related to the socioeconomic conditions of individuals, part of the spatial variation reflects residential segregation by income. Local characteristics also have a direct effect on health outcomes, shaping individuals' access to health services and the prevalence of unhealthy lifestyles. In addition, urban environments affect health through natural atmospheric conditions, through local infrastructure in particular water, sanitation, and urban transit and through the presence of urban externalities such as traffic congestion, pollution, crime, and the spread of transmissible diseases. The COVID-19 pandemic illustrates many of these patterns, since the impact of the disease has differed sharply across cities, and much of this variation can be explained by observable local characteristics particularly population, connectivity with other cities and countries, income levels, and residential overcrowding.
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Aalto, Juha, and Ari Venäläinen, eds. Climate change and forest management affect forest fire risk in Fennoscandia. Finnish Meteorological Institute, June 2021. http://dx.doi.org/10.35614/isbn.9789523361355.

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Forest and wildland fires are a natural part of ecosystems worldwide, but large fires in particular can cause societal, economic and ecological disruption. Fires are an important source of greenhouse gases and black carbon that can further amplify and accelerate climate change. In recent years, large forest fires in Sweden demonstrate that the issue should also be considered in other parts of Fennoscandia. This final report of the project “Forest fires in Fennoscandia under changing climate and forest cover (IBA ForestFires)” funded by the Ministry for Foreign Affairs of Finland, synthesises current knowledge of the occurrence, monitoring, modelling and suppression of forest fires in Fennoscandia. The report also focuses on elaborating the role of forest fires as a source of black carbon (BC) emissions over the Arctic and discussing the importance of international collaboration in tackling forest fires. The report explains the factors regulating fire ignition, spread and intensity in Fennoscandian conditions. It highlights that the climate in Fennoscandia is characterised by large inter-annual variability, which is reflected in forest fire risk. Here, the majority of forest fires are caused by human activities such as careless handling of fire and ignitions related to forest harvesting. In addition to weather and climate, fuel characteristics in forests influence fire ignition, intensity and spread. In the report, long-term fire statistics are presented for Finland, Sweden and the Republic of Karelia. The statistics indicate that the amount of annually burnt forest has decreased in Fennoscandia. However, with the exception of recent large fires in Sweden, during the past 25 years the annually burnt area and number of fires have been fairly stable, which is mainly due to effective fire mitigation. Land surface models were used to investigate how climate change and forest management can influence forest fires in the future. The simulations were conducted using different regional climate models and greenhouse gas emission scenarios. Simulations, extending to 2100, indicate that forest fire risk is likely to increase over the coming decades. The report also highlights that globally, forest fires are a significant source of BC in the Arctic, having adverse health effects and further amplifying climate warming. However, simulations made using an atmospheric dispersion model indicate that the impact of forest fires in Fennoscandia on the environment and air quality is relatively minor and highly seasonal. Efficient forest fire mitigation requires the development of forest fire detection tools including satellites and drones, high spatial resolution modelling of fire risk and fire spreading that account for detailed terrain and weather information. Moreover, increasing the general preparedness and operational efficiency of firefighting is highly important. Forest fires are a large challenge requiring multidisciplinary research and close cooperation between the various administrative operators, e.g. rescue services, weather services, forest organisations and forest owners is required at both the national and international level.
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Rahai, Hamid, and Jeremy Bonifacio. Numerical Investigations of Virus Transport Aboard a Commuter Bus. Mineta Transportation Institute, April 2021. http://dx.doi.org/10.31979/mti.2021.2048.

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The authors performed unsteady numerical simulations of virus/particle transport released from a hypothetical passenger aboard a commuter bus. The bus model was sized according to a typical city bus used to transport passengers within the city of Long Beach in California. The simulations were performed for the bus in transit and when the bus was at a bus stop opening the middle doors for 30 seconds for passenger boarding and drop off. The infected passenger was sitting in an aisle seat in the middle of the bus, releasing 1267 particles (viruses)/min. The bus ventilation system released air from two linear slots in the ceiling at 2097 cubic feet per minute (CFM) and the air was exhausted at the back of the bus. Results indicated high exposure for passengers sitting behind the infectious during the bus transit. With air exchange outside during the bus stop, particles were spread to seats in front of the infectious passenger, thus increasing the risk of infection for the passengers sitting in front of the infectious person. With higher exposure time, the risk of infection is increased. One of the most important factors in assessing infection risk of respiratory diseases is the spatial distribution of the airborne pathogens. The deposition of the particles/viruses within the human respiratory system depends on the size, shape, and weight of the virus, the morphology of the respiratory tract, as well as the subject’s breathing pattern. For the current investigation, the viruses are modeled as solid particles of fixed size. While the results provide details of particles transport within a bus along with the probable risk of infection for a short duration, however, these results should be taken as preliminary as there are other significant factors such as the virus’s survival rate, the size distribution of the virus, and the space ventilation rate and mixing that contribute to the risk of infection and have not been taken into account in this investigation.
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Ehrlich, Marcelo, John S. Parker, and Terence S. Dermody. Development of a Plasmid-Based Reverse Genetics System for the Bluetongue and Epizootic Hemorrhagic Disease Viruses to Allow a Comparative Characterization of the Function of the NS3 Viroporin in Viral Egress. United States Department of Agriculture, September 2013. http://dx.doi.org/10.32747/2013.7699840.bard.

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Project Title: "Development of a plasmid-based reverse genetics system for the Bluetongue and Epizootic Hemorrhagic Disease viruses to allow comparative characterization of the function of the NS3 viroporin in viral egress". Project details: No - IS-4192-09; Participants – Ehrlich M. (Tel Aviv University), Parker J.S. (Cornell University), DermodyT.S. (Vanderbilt University); Period - 2009-2013. Orbiviruses are insect-borne infectious agents of ruminants that cause diseases with considerable economical impact in Israel and the United States. The recent outbreaks of BTV in Europe and of Epizootic Hemorrhagic Disease Virus (EHDV) in Israel, underscore the need for: (i) a better comprehension of the infection process of orbiviruses, (ii) the identification of unique vs. common traits among different orbiviruses, (iii) the development of novel diagnosis and treatment techniques and approaches; all aimed at the achievement of more effective control and treatment measures. It is the context of these broad goals that the present project was carried out. To fulfill our long-term goal of identifying specific viral determinants of virulence, growth, and transmission of the orbiviruses, we proposed to: (i) develop reverse genetics systems for BTV and EHDV2-Ibaraki; and (ii) identify the molecular determinants of the NS3 nonstructural protein related to viroporin/viral egress activities. The first objective was pursued with a two-pronged approach: (i) development of a plasmid-based reverse genetics system for BTV-17, and (ii) development of an "in-vitro" transcription-based reverse genetics system for EHDV2-Ibaraki. Both approaches encountered technical problems that hampered their achievement. However, dissection of the possible causes of the failure to achieve viral spread of EHDV2-Ibaraki, following the transfection of in-vitro transcribed genomic segments of the virus, revealed a novel characteristic of EHDV2-Ibaraki infection: an uncharacteristically low fold increase in titer upon infection of different cell models. To address the function and regulation of NS3 we employed the following approaches: (i) development (together with Anima Cell Metrology) of a novel technique (based on the transfection of fluorescently-labeledtRNAs) that allows for the detection of the levels of synthesis of individual viral proteins (i.e. NS3) in single cells; (ii) development of a siRNA-mediated knockdown approach for the reduction in levels of expression of NS3 in EHDV2-Ibaraki infected cells; (iii) biochemical and microscopy-based analysis of the localization, levels and post-translational modifications of NS3 in infected cells. In addition, we identified the altered regulation and spatial compartmentalization of protein synthesis in cells infected with EHDV2-Ibaraki or the mammalian reovirus. In EHDV2-Ibaraki-infected cells such altered regulation in protein synthesis occurs in the context of a cell stress reponse that includes the induction of apoptosis, autophagy and activation of the stressrelated kinase c-Jun N-terminal Kinase (JNK). Interestingly, inhibition of such stress-related cellular processes diminishes the production of infectious virions, suggesting that EHDV usurps these responses for the benefit of efficient infection. Taken together, while the present project fell short of the generation of novel reverse genetics systems for orbiviruses, the development of novel experimental approaches and techniques, and their employment in the analysis of EHDV-infected cells, yielded novel insights in the interactions of orbiviruses with mammalian cells.
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10

Brophy, Kenny, and Alison Sheridan, eds. Neolithic Scotland: ScARF Panel Report. Society of Antiquaries of Scotland, June 2012. http://dx.doi.org/10.9750/scarf.06.2012.196.

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The main recommendations of the Panel report can be summarised as follows: The Overall Picture: more needs to be understood about the process of acculturation of indigenous communities; about the Atlantic, Breton strand of Neolithisation; about the ‘how and why’ of the spread of Grooved Ware use and its associated practices and traditions; and about reactions to Continental Beaker novelties which appeared from the 25th century. The Detailed Picture: Our understanding of developments in different parts of Scotland is very uneven, with Shetland and the north-west mainland being in particular need of targeted research. Also, here and elsewhere in Scotland, the chronology of developments needs to be clarified, especially as regards developments in the Hebrides. Lifeways and Lifestyles: Research needs to be directed towards filling the substantial gaps in our understanding of: i) subsistence strategies; ii) landscape use (including issues of population size and distribution); iii) environmental change and its consequences – and in particular issues of sea level rise, peat formation and woodland regeneration; and iv) the nature and organisation of the places where people lived; and to track changes over time in all of these. Material Culture and Use of Resources: In addition to fine-tuning our characterisation of material culture and resource use (and its changes over the course of the Neolithic), we need to apply a wider range of analytical approaches in order to discover more about manufacture and use.Some basic questions still need to be addressed (e.g. the chronology of felsite use in Shetland; what kind of pottery was in use, c 3000–2500, in areas where Grooved Ware was not used, etc.) and are outlined in the relevant section of the document. Our knowledge of organic artefacts is very limited, so research in waterlogged contexts is desirable. Identity, Society, Belief Systems: Basic questions about the organisation of society need to be addressed: are we dealing with communities that started out as egalitarian, but (in some regions) became socially differentiated? Can we identify acculturated indigenous people? How much mobility, and what kind of mobility, was there at different times during the Neolithic? And our chronology of certain monument types and key sites (including the Ring of Brodgar, despite its recent excavation) requires to be clarified, especially since we now know that certain types of monument (including Clava cairns) were not built during the Neolithic. The way in which certain types of site (e.g. large palisaded enclosures) were used remains to be clarified. Research and methodological issues: There is still much ignorance of the results of past and current research, so more effective means of dissemination are required. Basic inventory information (e.g. the Scottish Human Remains Database) needs to be compiled, and Canmore and museum database information needs to be updated and expanded – and, where not already available online, placed online, preferably with a Scottish Neolithic e-hub that directs the enquirer to all the available sources of information. The Historic Scotland on-line radiocarbon date inventory needs to be resurrected and kept up to date. Under-used resources, including the rich aerial photography archive in the NMRS, need to have their potential fully exploited. Multi-disciplinary, collaborative research (and the application of GIS modelling to spatial data in order to process the results) is vital if we are to escape from the current ‘silo’ approach and address key research questions from a range of perspectives; and awareness of relevant research outside Scotland is essential if we are to avoid reinventing the wheel. Our perspective needs to encompass multi-scale approaches, so that ScARF Neolithic Panel Report iv developments within Scotland can be understood at a local, regional and wider level. Most importantly, the right questions need to be framed, and the right research strategies need to be developed, in order to extract the maximum amount of information about the Scottish Neolithic.
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