Journal articles on the topic 'Spatial metrics'
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Koch, Julian, Mehmet Cüneyd Demirel, and Simon Stisen. "The SPAtial EFficiency metric (SPAEF): multiple-component evaluation of spatial patterns for optimization of hydrological models." Geoscientific Model Development 11, no. 5 (May 15, 2018): 1873–86. http://dx.doi.org/10.5194/gmd-11-1873-2018.
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Abstract. The process of model evaluation is not only an integral part of model development and calibration but also of paramount importance when communicating modelling results to the scientific community and stakeholders. The modelling community has a large and well-tested toolbox of metrics to evaluate temporal model performance. In contrast, spatial performance evaluation does not correspond to the grand availability of spatial observations readily available and to the sophisticate model codes simulating the spatial variability of complex hydrological processes. This study makes a contribution towards advancing spatial-pattern-oriented model calibration by rigorously testing a multiple-component performance metric. The promoted SPAtial EFficiency (SPAEF) metric reflects three equally weighted components: correlation, coefficient of variation and histogram overlap. This multiple-component approach is found to be advantageous in order to achieve the complex task of comparing spatial patterns. SPAEF, its three components individually and two alternative spatial performance metrics, i.e. connectivity analysis and fractions skill score, are applied in a spatial-pattern-oriented model calibration of a catchment model in Denmark. Results suggest the importance of multiple-component metrics because stand-alone metrics tend to fail to provide holistic pattern information. The three SPAEF components are found to be independent, which allows them to complement each other in a meaningful way. In order to optimally exploit spatial observations made available by remote sensing platforms, this study suggests applying bias insensitive metrics which further allow for a comparison of variables which are related but may differ in unit. This study applies SPAEF in the hydrological context using the mesoscale Hydrologic Model (mHM; version 5.8), but we see great potential across disciplines related to spatially distributed earth system modelling.
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Fry, Edward W. S., Sophie Triantaphillidou, Robin B. Jenkin, Ralph E. Jacobson, and John R. Jarvis. "Scene-and-Process-Dependent Spatial Image Quality Metrics." Journal of Imaging Science and Technology 63, no. 6 (November 1, 2019): 60407–1. http://dx.doi.org/10.2352/j.imagingsci.technol.2019.63.6.060407.
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Abstract Spatial image quality metrics designed for camera systems generally employ the Modulation Transfer Function (MTF), the Noise Power Spectrum (NPS) and a visual contrast detection model. Prior art indicates that scene-dependent characteristics of non-linear, content-aware image processing are unaccounted for by MTFs and NPSs measured by traditional methods. The authors present two novel metrics: the log Noise Equivalent Quanta (log NEQ) and Visual log NEQ. They both employ Scene-and-Process-Dependent MTF (SPD-MTF) and NPS (SPD-NPS) measures, which account for signal transfer and noise scene dependency, respectively. The authors also investigate implementing contrast detection and discrimination models that account for scene-dependent visual masking. Also, three leading camera metrics are revised to use the above scene-dependent measures. All metrics are validated by examining correlations with the perceived quality of images produced by simulated camera pipelines. Metric accuracy improved consistently when the SPD-MTFs and SPD-NPSs were implemented. The novel metrics outperformed existing metrics of the same genre.
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Parisien, Marc-André, Vernon S. Peters, Yonghe Wang, John M. Little, Erin M. Bosch, and Brian J. Stocks. "Spatial patterns of forest fires in Canada, 1980 - 1999." International Journal of Wildland Fire 15, no. 3 (2006): 361. http://dx.doi.org/10.1071/wf06009.
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The present study characterized the spatial patterns of forest fires in 10 fire-dominated ecozones of Canada by using a database of mapped fires ≥200 ha from 1980 to 1999 (n = 5533 fires). Spatial metrics were used individually to compare measures of fire size, shape (eccentricity and complexity), clustering, and geographic orientation among ecozones and were used concurrently in a multivariate analysis. In addition, a set of factors that influence the fire regime at the ecozone level – topography, climate, fuels, and anthropogenic factors – was compared with the metric outputs. We found significant differences in all spatial metrics among ecozones. The multivariate analysis showed that the Montane Cordillera ecozone, which covers most of British Columbia, had the most distinctive fires: its fires were smaller, less complex, and had a more regular distribution. The fire regime descriptors of ecozones were useful to interpret the spatial variation of some spatial metrics, such as fire size, eccentricity, and clustering, but provided little insight into the mechanisms of patterns of fire complexity, which were shown to be sensitive to data quality. Our results provide additional information about the creation of spatially heterogeneous landscapes. Furthermore, they illustrate the potential use of spatial metrics for a more detailed characterization of fire regimes and provide novel information for ecosystems-based land management.
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Crowder, David W., and Panayiotis Diplas. "Evaluating spatially explicit metrics of stream energy gradients using hydrodynamic model simulations." Canadian Journal of Fisheries and Aquatic Sciences 57, no. 7 (July 1, 2000): 1497–507. http://dx.doi.org/10.1139/f00-074.
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Localized energy gradients and velocity shelters created by boulders, bars, and channel banks are often essential components of aquatic habitat. Two-dimensional hydraulic models have the potential to predict the amounts and locations of such spatially varying flow patterns. However, little effort has been devoted to reproducing these flow features and developing spatial habitat metrics to describe and differentiate between various types of flow patterns. Two-dimensional numerical simulations, based on actual channel geometry, are used here to model a variety of flow patterns encountered in natural streams. The simulation results are used to develop spatial habitat metrics that quantify local velocity gradients and changes in kinetic energy. The proposed metrics are evaluated at various points within the different flow patterns of interest. The metrics produce large values for flow patterns exhibiting considerable spatial variation and small values in areas experiencing uniform flow conditions. Comparisons with other researchers' field data suggest that the metric values produced in the modeled flows are consistent with values found near fish resting and feeding locations. The habitat metrics, measures of the flow's rate of spatial change in kinetic energy, can also be incorporated into bioenergetic models to facilitate the computation of fish energy expenditure rates.
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Crowder, David W., and Panayiotis Diplas. "Vorticity and circulation: spatial metrics for evaluating flow complexity in stream habitats." Canadian Journal of Fisheries and Aquatic Sciences 59, no. 4 (April 1, 2002): 633–45. http://dx.doi.org/10.1139/f02-037.
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Channel topography, formed by boulders, submerged bars, and meanders, creates complex flow patterns. These flow patterns exist over a variety of spatial scales and provide habitat for many aquatic organisms. Spatial flow features cannot be adequately characterized with qualitative descriptions or hydraulic metrics such as depth and velocity. Two-dimensional hydraulic model simulations, based on detailed channel geometry, are used to develop and test vorticity (a point metric) and a circulation-based metric (an area metric) as means of quantifying spatial flows occurring within micro-, meso-, and macro-habitat features. The proposed spatial metrics are computed throughout distinctly different regions of a study site. The vorticity metric produces small absolute values in uniform flows and large absolute values in complex flows. Circulation metric values varied by a factor of 11.7 within distinctly different regions of the modeled study site and suggest that the metric provides a means of quantifying flow complexity within a study reach or within individual mesoscale habitats such as pools, eddies, riffles, and transverse flows. The circulation metric is used to quantify flow complexity around three brown trout (Salmo trutta) redds to provide an example of how the proposed metric might be employed in habitat studies.
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Fu, Gang, Wei Wang, Junsheng Li, Nengwen Xiao, and Yue Qi. "Prediction and Selection of Appropriate Landscape Metrics and Optimal Scale Ranges Based on Multi-Scale Interaction Analysis." Land 10, no. 11 (November 5, 2021): 1192. http://dx.doi.org/10.3390/land10111192.
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Landscape metrics are widely used in landscape planning and land use management. Understanding how landscape metrics respond with scales can provide more accurate prediction information; however, ignoring the interference of multi-scale interaction may lead to a severe systemic bias. In this study, we quantitatively analyzed the scaling sensitivity of metrics based on multi-scale interaction and predict their optimal scale ranges. Using a big data method, the multivariate adaptive regression splines model (MARS), and the partial dependence model (PHP), we studied the scaling relationships of metrics to changing scales. The results show that multi-scale interaction commonly exists in most landscape metric scaling responses, making a significant contribution. In general, the scaling effects of the three scales (i.e., spatial extent, spatial resolution, and classification of land use) are often in a different direction, and spatial resolution is the primary driving scale in isolation. The findings show that only a few metrics are highly sensitive to the three scales throughout the whole scale spectrum, while the other metrics are limited within a certain threshold range. This study confirms that the scaling-sensitive scalograms can be used as an application guideline for selecting appropriate landscape metrics and optimal scale ranges.
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Ibadah, Nisrine, Khalid Minaoui, Mohammed Rziza, Mohammed Oumsis, and César Benavente-Peces. "Deep Validation of Spatial Temporal Features of Synthetic Mobility Models." Computers 7, no. 4 (December 16, 2018): 71. http://dx.doi.org/10.3390/computers7040071.
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This paper analyzes the most relevant spatial-temporal stochastic properties of benchmark synthetic mobility models. Each pattern suffers from various mobility flaws, as will be shown by the models’ validation. A set of metrics is used to describe mobility features, such as the speed decay problem, the density wave phenomenon, the spatial node distribution, and the average neighbor percentage. These metrics have already been validated for the random waypoint mobility model (RWPMM), but they have not yet been verified for other mobility patterns that are most frequently used. For this reason, this investigation attempts to deeply validate those metrics for other mobility models, namely the Manhattan Grid mobility, the Reference Point Group mobility, the Nomadic Community mobility, the Self-Similar Least Action Walk, and SMOOTH models. Moreover, we propose a novel mobility metric named the “node neighbors range”. The relevance of this new metric is that it proves at once the set of outcomes of previous metrics. It offers a global view of the overall range of mobile neighbors during the experimental time. The current research aims to more rigorously understand mobility features in order to conduct a precise assessment of each mobility flaw, given that this fact further impacts the performance of the whole network. These validations aim to summarize several parameters into 18,126 different scenarios with an average of 486 validated files. An exhaustive analysis with details like those found in this paper leads to a good understanding of the accurate behaviors of mobility models by displaying the ability of every pattern to deal with certain topology changes, as well as to ensure network performances. Validation results confirm the effectiveness and robustness of our novel metric.
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Wohlgemuth, Melville, Angeles Salles, and Cynthia Moss. "Spatial attention in natural tasks." Molecular Psychology: Brain, Behavior, and Society 1 (December 22, 2022): 4. http://dx.doi.org/10.12688/molpsychol.17488.1.
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Little is known about fine scale neural dynamics that accompany rapid shifts in spatial attention in freely behaving animals, primarily because reliable indicators of attention are lacking in standard model organisms engaged in natural tasks. The echolocating bat can serve to bridge this gap, as it exhibits robust dynamic behavioral indicators of overt spatial attention as it explores its environment. In particular, the bat actively shifts the aim of its sonar beam to inspect objects in different directions, akin to eye movements and foveation in humans and other visually dominant animals. Further, the bat adjusts the temporal features of sonar calls to attend to objects at different distances, yielding a metric of acoustic gaze along the range axis. Thus, an echolocating bat’s call features not only convey the information it uses to probe its surroundings, but also provide fine scale metrics of auditory spatial attention in 3D natural tasks. These explicit metrics of overt spatial attention can be leveraged to uncover general principles of neural coding in the mammalian brain.
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Israel, Emil, and Amnon Frenkel. "Social justice and spatial inequality." Progress in Human Geography 42, no. 5 (April 21, 2017): 647–65. http://dx.doi.org/10.1177/0309132517702969.
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Justice has recently been deliberated in different spatial disciplines. Still, the question of its metrics remains unresolved. Accordingly, this article introduces a conceptual framework in which a metric notion of justice can be employed in different spatial contexts, drawing upon the theoretical conceptualization of Amartya Sen’s ‘capabilities’ and Pierre Bourdieu’s ‘field’, capital forms and ‘habitus’. The main hypothesis assumes that capital resources, which are formed in an individual’s living environment, determine their life chances, thus influencing spatial equality of opportunity (i.e. social justice).
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Biraghi, C. A., and E. Lenzi. "SPATIAL PATTERN ANALYSIS THROUGH DISTRIBUTION METRICS." International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B4-2022 (June 1, 2022): 69–77. http://dx.doi.org/10.5194/isprs-archives-xliii-b4-2022-69-2022.
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Abstract. Moving from the controversial results on the link between urban structure and performance aspect, this article wants to encourage the development of the independent research on urban structure, and more generally on spatial patterns, at different scales to enable future further correlations with a wider set of performance aspects (environmental, social, economic, medical). The work also exploits the potential of several unsupervised learning algorithms, whose performance and power are increasingly promising and whose use is becoming more widespread in different fields; but for which there are still many challenges concerning the correct application in urban areas and the interpretability of the results. We propose an approach for the creation of new spatial attributes and metrics (features) aiming to quantitatively describe the qualitative distribution of objects (e.g., buildings) in a 2D space. It explores an incremental bottom-up process for the creation of groups of objects (e.g., urban patches) and the evaluation of their physical properties alone and in respect with a sample area at each iteration. The process consists of 7 phases: data preparation, data processing, parameters collection, feature calculation, feature selection, clustering, results comparison. The results can be mainly divided in two. First, the feature selection allowed to extract a minimum set of non-redundant, valid, and consistent features that can explain qualitative distribution aspects of spatial patterns. Second, the comparison between feature-based and neural network clustering, gave useful insights for a preliminary understanding of unsupervised learning techniques internal mechanisms.
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Rinck, Mike, Andrea Hähnel, Gordon H. Bower, and Ulrich Glowalla. "The metrics of spatial situation models." Journal of Experimental Psychology: Learning, Memory, and Cognition 23, no. 3 (1997): 622–37. http://dx.doi.org/10.1037/0278-7393.23.3.622.
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Souza, Bryan C., Rodrigo Pavão, Hindiael Belchior, and Adriano B. L. Tort. "On Information Metrics for Spatial Coding." Neuroscience 375 (April 2018): 62–73. http://dx.doi.org/10.1016/j.neuroscience.2018.01.066.
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Vigness-Raposa, Kathleen J., Adam S. Frankel, Jennifer Giard, Kenneth T. Hunter, and William T. Ellison. "Acoustic scene metrics for spatial planning." Journal of the Acoustical Society of America 135, no. 4 (April 2014): 2367. http://dx.doi.org/10.1121/1.4877803.
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Zhang, Ying, Jingxiong Zhang, Fengyan Wang, and Wenjing Yang. "Spatiotemporal Landscape Pattern Analyses Enhanced by an Integrated Index: A Study of the Changbai Mountain National Nature Reserve." Remote Sensing 15, no. 7 (March 24, 2023): 1760. http://dx.doi.org/10.3390/rs15071760.
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The analysis of spatiotemporal changes of landscape patterns is of great significance for forest protection. However, the selection of landscape metrics is often subjective, and existing composite landscape metrics rarely consider the effects of spatial correlation. A more objective approach to formulating composite landscape metrics involves proper weighting that incorporates spatial structure information into integrating individual conventional metrics selected for building a composite metric. This paper proposes an integrated spatial landscape index (ISLI) based on variogram modeling and entropy weighting. It was tested through a case study, which sought to analyze spatiotemporal changes in the landscape pattern in the Changbai Mountains over 30 years based on six global land-cover products with a fine classification system at 30 m resolution (GLC_FCS30). The test results confirm: (1) spatial structure information is useful for weighting conventional landscape pattern metrics when constructing ISLI as validated by correlation analysis between the incorporated conventional metrics and their variogram ranges. In terms of the range parameters of different land cover types, broadleaf forest and needleleaf forest have much larger range values than those of other land cover types; (2) DIVISION and PLAND, two of the conventional landscape metrics considered for constructing ISLI, were assigned the greatest weights in computing ISLI for this study; and (3) ISLI values can be used to determine the dominant landscape types. For the study area, ISLI values of broadleaf forests remained the largest until 2020, indicating that forest landscape characteristics were the most prominent during that period. After 2020, the dominance of needleleaf forest gradually increased, with its ISLI value reaching a maximum of 0.91 in 2025. Therefore, the proposed ISLI not only functions as an extension and complement to conventional landscape metrics but also provides more comprehensive information concerning landscape pattern dynamics.
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Skok, Gregor. "A New Spatial Distance Metric for Verification of Precipitation." Applied Sciences 12, no. 8 (April 16, 2022): 4048. http://dx.doi.org/10.3390/app12084048.
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Precipitation is an essential meteorological variable affecting the biosphere and human societies. At the same time, precipitation is notoriously difficult to predict and verify. A new spatial distance metric for verification of precipitation is presented. It is called the Precipitation Smoothing Distance (PSD). The aim was to develop a measure that would provide a good and meaningful approximation of the displacement of precipitation events in the two fields. An estimate of spatial displacement is very appealing for forecast interpretation because it is easy to understand and mimics how humans tend to judge fields by eye. Contrary to most other distance metrics, the new metric does not require thresholding and can thus be used to analyze binary and non-binary fields (e.g., continuous or multi-level). The analysis of idealized situations showed that the new metric provides a meaningful approximation of the displacement. Typically the estimate of displacement provided by PSD was better than the results provided by most other metrics. The measure is also not overly sensitive to noise, its results are directly related to the actual displacements of precipitation events, and the events with a larger magnitude have a bigger influence on the resulting value. The analysis of ECMWF precipitation forecasts over Europe and North Africa confirmed that the new metric provides a meaningful approximation of the displacement even in more complex real-world situations.
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Warren, Joshua L., Montserrat Fuentes, Amy H. Herring, and Peter H. Langlois. "Air Pollution Metric Analysis While Determining Susceptible Periods of Pregnancy for Low Birth Weight." ISRN Obstetrics and Gynecology 2013 (January 30, 2013): 1–9. http://dx.doi.org/10.1155/2013/387452.
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Multiple metrics to characterize air pollution are available for use in environmental health analyses in addition to the standard Air Quality System (AQS) pollution monitoring data. These metrics have complete spatial-temporal coverage across a domain and are therefore crucial in calculating pollution exposures in geographic areas where AQS monitors are not present. We investigate the impact that two of these metrics, output from a deterministic chemistry model (CMAQ) and from a spatial-temporal downscaler statistical model which combines information from AQS and CMAQ (DS), have on risk assessment. Using each metric, we analyze ambient ozone's effect on low birth weight utilizing a Bayesian temporal probit regression model. Weekly windows of susceptibility are identified and analyzed jointly for all births in a subdomain of Texas, 2001–2004, and results from the different pollution metrics are compared. Increased exposures during weeks 20–23 of the pregnancy are identified as being associated with low birth weight by the DS metric. Use of the CMAQ output alone results in increased variability of the final risk assessment estimates, while calibrating the CMAQ through use of the DS metric provides results more closely resembling those of the AQS. The AQS data are still preferred when available.
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Choudhury, Anustup, and Scott Daly. "Comparing a spatial extension of ICTCP color representation with S-CIELAB and other recent color metrics for HDR and WCG quality assessment." Electronic Imaging 2020, no. 15 (January 26, 2020): 162–1. http://dx.doi.org/10.2352/issn.2470-1173.2020.15.color-123.
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Content created in High Dynamic Range (HDR) and Wide Color Gamut (WCG) is becoming more ubiquitous, driving the need for reliable tools for evaluating the quality across the imaging ecosystem. One of the simplest techniques to measure the quality of any video system is to measure the color errors. The traditional color difference metrics such as ΔE00 and the newer HDR specific metrics such as ΔEZ and ΔEITP compute color difference on a pixel-by-pixel basis which do not account for the spatial effects (optical) and active processing (neural) done by the human visual system. In this work, we improve upon the per-pixel ΔEITP color difference metric by performing a spatial extension similar to what was done during the design of S-CIELAB. We quantified the performance using four standard evaluation procedures on four publicly available HDR and WCG image databases and found that the proposed metric results in a marked improvement with subjective scores over existing per-pixel color difference metrics.
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Wang, Yuwei, and Dorukalp Durmus. "Image Quality Metrics, Personality Traits, and Subjective Evaluation of Indoor Environment Images." Buildings 12, no. 12 (November 28, 2022): 2086. http://dx.doi.org/10.3390/buildings12122086.
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Adaptive lighting systems can be designed to detect the spatial characteristics of the visual environment and adjust the light output to increase visual comfort and performance. Such systems would require computational metrics to estimate occupants’ visual perception of indoor environments. This paper describes an experimental study to investigate the relationship between the perceived quality of indoor environments, personality, and computational image quality metrics. Forty participants evaluated the visual preference, clarity, complexity, and colorfulness of 50 images of indoor environments. Twelve image quality metrics (maximum local variation (MLV), spatial frequency slope (α), BRISQUE, entropy (S), ITU spatial information (SI), visual complexity (Rspt), colorfulness (M), root mean square (RMS) contrast, Euler, energy (E), contour, and fractal dimension) were used to estimate participants’ subjective evaluations. While visual clarity, visual complexity, and colorfulness could be estimated using at least one metric, none of the metrics could estimate visual preference. The results indicate that perceived colorfulness is highly correlated with perceived clarity and complexity. Personality traits tested by the 10-item personality inventory (TIPI) did not impact the subjective evaluations of the indoor environmental images. Future studies will explore the impact of target and background luminance on the perceived quality of indoor images.
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Yang, Chun Ting, Yang Liu, and Jing Yu. "Research on Video Sequences Quality Based on Motion Intensity." Applied Mechanics and Materials 20-23 (January 2010): 1476–81. http://dx.doi.org/10.4028/www.scientific.net/amm.20-23.1476.
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Perception video sequences quality metrics are of great potential benefit to the video industry, as they promise the means to evaluate the performance of acquisition, display, coding and communication systems. Many researchers have focused on developing digital video sequences quality metrics which produce results that accurately emulate subjective responses. However, to be widely applicable a metric must also work over a wide range of quality, and be useful for in-service quality monitoring. We have developed novel video distortion metrics for video sequences. The temporal correlations of video frames and the visual interest feature are considered in this method. Meanwhile the metrics are capable of capturing spatial distortions in video sequences. The metrics correlate well with subjective video transmission quality measures because perception distortions of human were took account of. Results are presented that demonstrate our perceptual quality metric performs better than existing methods.
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Gold, N. E., A. M. Mohan, and P. J. Layzell. "Spatial complexity metrics: an investigation of utility." IEEE Transactions on Software Engineering 31, no. 3 (March 2005): 203–12. http://dx.doi.org/10.1109/tse.2005.39.
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Lowry, John H., and Michael B. Lowry. "Comparing spatial metrics that quantify urban form." Computers, Environment and Urban Systems 44 (March 2014): 59–67. http://dx.doi.org/10.1016/j.compenvurbsys.2013.11.005.
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Valenzuela, Alvaro Q., and Juan Carlos G. Reyes. "Basic Spatial Resolution Metrics for Satellite Imagers." IEEE Sensors Journal 19, no. 13 (July 1, 2019): 4914–22. http://dx.doi.org/10.1109/jsen.2019.2902512.
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Ziegeler, Sean B., James D. Dykes, and Jay F. Shriver. "Spatial Error Metrics for Oceanographic Model Verification." Journal of Atmospheric and Oceanic Technology 29, no. 2 (February 1, 2012): 260–66. http://dx.doi.org/10.1175/jtech-d-11-00109.1.
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Abstract A common problem with modern numerical oceanographic models is spatial displacement, including misplacement and misshapenness of ocean circulation features. Traditional error metrics, such as least squares methods, are ineffective in many such cases; for example, only small errors in the location of a frontal pattern are translated to large differences in least squares of intensities. Such problems are common in meteorological forecast verification as well, so the application of spatial error metrics have been a recently popular topic there. Spatial error metrics separate model error into a displacement component and an intensity component, providing a more reliable assessment of model biases and a more descriptive portrayal of numerical model prediction skill. The application of spatial error metrics to oceanographic models has been sparse, and further advances for both meteorology and oceanography exist in the medical imaging field. These advances are presented, along with modifications necessary for oceanographic model output. Standard methods and options for those methods in the literature are explored, and where the best arrangements of options are unclear, comparison studies are conducted. These trials require the reproduction of synthetic displacements in conjunction with synthetic intensity perturbations across 480 Navy Coastal Ocean Model (NCOM) temperature fields from various regions of the globe throughout 2009. Study results revealed the success of certain approaches novel to both meteorology and oceanography, including B-spline transforms and mutual information. That, combined with other common methods, such as quasi-Newton optimization and land masking, could best recover the synthetic displacements under various synthetic intensity changes.
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Kedron, Peter, Yun Zhao, and Amy E. Frazier. "Three dimensional (3D) spatial metrics for objects." Landscape Ecology 34, no. 9 (June 28, 2019): 2123–32. http://dx.doi.org/10.1007/s10980-019-00861-4.
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Martinez, J. M. R., and J. Duffy. "On the Metrics of Rigid Body Displacements for Infinite and Finite Bodies." Journal of Mechanical Design 117, no. 1 (March 1, 1995): 41–47. http://dx.doi.org/10.1115/1.2826115.
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This paper presents a critical analysis of the metric of rigid body displacements obtained from the so-called kinematic mapping. It is shown that this metric is not suitable for finite rigid bodies. The paper also addresses the metrics obtained for the planar group, as it can be regarded as a subgroup of the group of all rigid body displacements, which is denoted here as the Euclidean group. Finally, the paper proposes some metrics for the set of spatial and planar displacements for a finite rigid body, undergoing a finite displacement.
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Li, Cheng, Jie Zhao, Nguyen Xuan Thinh, Wenfu Yang, and Zhen Li. "ANALYSIS OF THE SPATIOTEMPORALLY VARYING EFFECTS OF URBAN SPATIAL PATTERNS ON LAND SURFACE TEMPERATURES." Journal of Environmental Engineering and Landscape Management 26, no. 3 (October 9, 2018): 216–31. http://dx.doi.org/10.3846/jeelm.2018.5378.
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Urban heat islands (UHIs) are a worldwide phenomenon that have many ecological and social consequences. It has become increasingly important to examine the relationships between land surface temperatures (LSTs) and all related factors. This study analyses Landsat data, spatial metrics, and a geographically weighted regression (GWR) model for a case study of Hangzhou, China, to explore the correlation between LST and urban spatial patterns. The LST data were retrieved from Landsat images. Spatial metrics were used to quantify the urban spatial patterns. The effects of the urban spatial patterns on LSTs were further investigated using Pearson correlation analysis and a GWR model, both at three spatial scales. The results show that the LST patterns have changed significantly, which can be explained by the concurrent changes in urban spatial patterns. The correlation coefficients between the spatial metrics and LSTs decrease as the spatial scale increases. The GWR model performs better than an ordinary least squares analysis in exploring the relationship of LSTs and urban spatial patterns, which is indicated by the higher adjusted R2 values, lower corrected Akaike information criterion and reduced spatial autocorrelations. The GWR model results indicate that the effects of urban spatial patterns on LSTs are spatiotemporally variable. Moreover, their effects vary spatially with the use of different spatial scales. The findings of this study can aid in sustainable urban planning and the mitigation the UHI effect.
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Gavrilovic, Suzana, Nevena Vasiljevic, Boris Radic, and Vladimir Pihler. "Landscape metrics application in ecological and visual landscape assessment." Bulletin of the Faculty of Forestry, no. 116 (2017): 29–50. http://dx.doi.org/10.2298/gsf1716029g.
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The development of landscape-ecological approach application in spatial planning provides exact theoretical and empirical evidence for monitoring ecological consequences of natural and/or anthropogenic factors, particularly changes in spatial structures caused by them. Landscape pattern which feature diverse landscape values is the holder of the unique landscape character at different spatial levels and represents a perceptual domain for its users. Using the landscape metrics, the parameters of landscape composition and configuration are mathematical algorithms that quantify the specific spatial characteristics used for interpretation of landscape features and processes (physical and ecological aspect), as well as forms (visual aspect) and the meaning (cognitive aspect) of the landscape. Landscape metrics has been applied mostly in the ecological and biodiversity assessments as well as in the determination of the level of structural change of landscape, but more and more applied in the assessment of the visual character of the landscape. Based on a review of relevant literature, the aim of this work is to show the main trends of landscape metrics within the aspect of ecological and visual assessments. The research methodology is based on the analysis, classification and systematization of the research studies published from 2000 to 2016, where the landscape metrics is applied: (1) the analysis of landscape pattern and its changes, (2) the analysis of biodiversity and habitat function and (3) a visual landscape assessment. By selecting representative metric parameters for the landscape composition and configuration, for each category is formed the basis for further landscape metrics research and application for the integrated ecological and visual assessment of the landscape values. Contemporary conceptualization of the landscape is seen holistically, and the future research should be directed towards the development of integrated landscape assessment as a guideline for spatial development planning.
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Herold, Martin, Joseph Scepan, and Keith C. Clarke. "The Use of Remote Sensing and Landscape Metrics to Describe Structures and Changes in Urban Land Uses." Environment and Planning A: Economy and Space 34, no. 8 (August 2002): 1443–58. http://dx.doi.org/10.1068/a3496.
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Remote sensing technology has great potential for acquisition of detailed and accurate land-use information for management and planning of urban regions. However, the determination of land-use data with high geometric and thematic accuracy is generally limited by the availability of adequate remote sensing data, in terms of spatial and temporal resolution, and digital image analysis techniques. This study introduces a methodology using information on image spatial form—landscape metrics—to describe urban land-use structures and land-cover changes that result from urban growth. The analysis is based on spatial analysis of land-cover structures mapped from digitally classified aerial photographs of the urban region Santa Barbara, CA. Landscape metrics were calculated for segmented areas of homogeneous urban land use to allow a further characterization of the land use of these areas. The results show a useful separation and characterization of three urban land-use types: commercial development, high-density residential, and low-density residential. Several important structural land-cover features were identified for this study. These were: the dominant general land cover (built up or vegetation), the housing density, the mean structure and plot size, and the spatial aggregation of built-up areas. For two test areas in the Santa Barbara region, changes (urban growth) in the urban spatial land-use structure can be described and quantified with landscape metrics. In order to discriminate more accurately between the three land-cover types of interest, the landscape metrics were further refined into what are termed ‘landscape metric signatures’ for the land-use categories. The analysis shows the importance of the spatial measurements as second-order image information that can contribute to more detailed mapping of urban areas and towards a more accurate characterization of spatial urban growth pattern.
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Turetta, Ana Paula Dias, Rachel Bardy Prado, and Gustavo de Souza Valladares. "Evaluating the Potential of Landscape Metrics in Supporting Landscape Planning in Atlantic Forest." International Journal of Agricultural and Environmental Information Systems 4, no. 1 (January 2013): 55–67. http://dx.doi.org/10.4018/jaeis.2013010104.
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The landscapes are highly dependent on the dynamics of local land use and land cover, which directly affects landscape structure and determines the spatial patterns of forest patches, as well as to the major land uses within a specific region. The calculation of landscape metrics can support the understanding of such spatial distribution. In this study, 16 landscape metrics were analyzed in a drainage watershed in a high relief region in the Rio de Janeiro state, Southeastern Brazil, with the aim to evaluate the use of landscape metrics as indicators for agricultural management. Metrics calculation was followed by a Principal Component Analysis, which indicated the metrics that were most effective in evidencing the landscape structure in analysis. The results showed that the late-succession forest is the dominant component in the landscape. This class also presented the highest MPS metric value, related to the mean patch size by class. Some PCA results suggest that the metrics association was less effective in clustering the overgrown pasture, clean pasture, and annual crops classes, but this could result from the intrinsic association among those classes, by crop rotation, meaning the abandon of a site formerly occupied by an annual crop. Some metrics better suggested an interaction among land use classes and have potential to be use in the analyses of agricultural landscapes in high relief sites.
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Berman, Ethan E., Tabitha A. Graves, Nate L. Mikle, Jerod A. Merkle, Aaron N. Johnston, and Geneva W. Chong. "Comparative Quality and Trend of Remotely Sensed Phenology and Productivity Metrics across the Western United States." Remote Sensing 12, no. 16 (August 7, 2020): 2538. http://dx.doi.org/10.3390/rs12162538.
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Vegetation phenology and productivity play a crucial role in surface energy balance, plant and animal distribution, and animal movement and habitat use and can be measured with remote sensing metrics including start of season (SOS), peak instantaneous rate of green-up date (PIRGd), peak of season (POS), end of season (EOS), and integrated vegetation indices. However, for most metrics, we do not yet understand the agreement of remotely sensed data products with near-surface observations. We also need summaries of changes over time, spatial distribution, variability, and consistency in remote sensing dataset metrics for vegetation timing and quality. We compare metrics from 10 leading remote sensing datasets against a network of PhenoCam near-surface cameras throughout the western United States from 2002 to 2014. Most phenology metrics representing a date (SOS, PIRGd, POS, and EOS), rather than a duration (length of spring, length of growing season), better agreed with near-surface metrics but results varied by dataset, metric, and land cover, with absolute value of mean bias ranging from 0.38 (PIRGd) to 37.92 days (EOS). Datasets had higher agreement with PhenoCam metrics in shrublands, grasslands, and deciduous forests than in evergreen forests. Phenology metrics had higher agreement than productivity metrics, aside from a few datasets in deciduous forests. Using two datasets covering the period 1982–2016 that best agreed with PhenoCam metrics, we analyzed changes over time to growing seasons. Both datasets exhibited substantial spatial heterogeneity in the direction of phenology trends. Variability of metrics increased over time in some areas, particularly in the Southwest. Approximately 60% of pixels had consistent trend direction between datasets for SOS, POS, and EOS, with the direction varying by location. In all ecoregions except Mediterranean California, EOS has become later. This study comprehensively compares remote sensing datasets across multiple growing season metrics and discusses considerations for applied users to inform their data choices.
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Nikfar, Mehdi, Haoyang Mi, Chang Gong, Holly Kimko, and Aleksander S. Popel. "Quantifying Intratumoral Heterogeneity and Immunoarchitecture Generated In-Silico by a Spatial Quantitative Systems Pharmacology Model." Cancers 15, no. 10 (May 13, 2023): 2750. http://dx.doi.org/10.3390/cancers15102750.
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Spatial heterogeneity is a hallmark of cancer. Tumor heterogeneity can vary with time and location. The tumor microenvironment (TME) encompasses various cell types and their interactions that impart response to therapies. Therefore, a quantitative evaluation of tumor heterogeneity is crucial for the development of effective treatments. Different approaches, such as multiregional sequencing, spatial transcriptomics, analysis of autopsy samples, and longitudinal analysis of biopsy samples, can be used to analyze the intratumoral heterogeneity (ITH) and temporal evolution and to reveal the mechanisms of therapeutic response. However, because of the limitations of these data and the uncertainty associated with the time points of sample collection, having a complete understanding of intratumoral heterogeneity role is challenging. Here, we used a hybrid model that integrates a whole-patient compartmental quantitative-systems-pharmacology (QSP) model with a spatial agent-based model (ABM) describing the TME; we applied four spatial metrics to quantify model-simulated intratumoral heterogeneity and classified the TME immunoarchitecture for representative cases of effective and ineffective anti-PD-1 therapy. The four metrics, adopted from computational digital pathology, included mixing score, average neighbor frequency, Shannon’s entropy and area under the curve (AUC) of the G-cross function. A fifth non-spatial metric was used to supplement the analysis, which was the ratio of the number of cancer cells to immune cells. These metrics were utilized to classify the TME as “cold”, “compartmentalized” and “mixed”, which were related to treatment efficacy. The trends in these metrics for effective and ineffective treatments are in qualitative agreement with the clinical literature, indicating that compartmentalized immunoarchitecture is likely to result in more efficacious treatment outcomes.
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Lee, Jaewook, and Mohamed Boubekri. "INTRODUCTION OF NEW DAYLIGHTING METRICS FOR HEALTH, WELLBEING, AND FEASIBILITY: A STUDY OF THE INDOOR BUILDING ENVIRONMENT." Journal of Green Building 17, no. 1 (January 1, 2022): 105–26. http://dx.doi.org/10.3992/1943-4618.17.1.105.
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ABSTRACT This study investigates the applicability of a new daylighting metric based on human health, an emerging framework for evaluating the effect of daylight on building occupants. Procedures based on modeling annual daylight availability are used to determine the mapping of daylight distribution on a daily, seasonal, and yearly basis. Literature review and experimental studies were performed to propose the new day-lighting metrics for health and wellbeing. The proposed metrics have two broad criteria, including daylighting level, timing, and duration. The two details are as follows: (1) 400 lux for 5 hours (2K lux·h) in the daytime; and (2) 500 lux for 1 hour (0.5K lux·h) in the early morning, 8AM–9AM. To verify the applicability of the proposed daylighting metrics to current buildings, sample buildings were selected and daily, spatial and seasonal differences were simulated through computer visualization techniques. Moreover, we evaluated the application of the daylighting metric on the building layout and compared the new daylighting metric for health and wellbeing with conventional daylighting metrics.
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Lee, Jaewook, and Mohamed Boubekri. "INTRODUCTION OF NEW DAYLIGHTING METRICS FOR HEALTH, WELLBEING, AND FEASIBILITY: A STUDY OF THE INDOOR BUILDING ENVIRONMENT." Journal of Green Building 17, no. 1 (January 1, 2022): 105–26. http://dx.doi.org/10.3992/jgb.17.1.105.
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ABSTRACT This study investigates the applicability of a new daylighting metric based on human health, an emerging framework for evaluating the effect of daylight on building occupants. Procedures based on modeling annual daylight availability are used to determine the mapping of daylight distribution on a daily, seasonal, and yearly basis. Literature review and experimental studies were performed to propose the new day-lighting metrics for health and wellbeing. The proposed metrics have two broad criteria, including daylighting level, timing, and duration. The two details are as follows: (1) 400 lux for 5 hours (2K lux·h) in the daytime; and (2) 500 lux for 1 hour (0.5K lux·h) in the early morning, 8AM–9AM. To verify the applicability of the proposed daylighting metrics to current buildings, sample buildings were selected and daily, spatial and seasonal differences were simulated through computer visualization techniques. Moreover, we evaluated the application of the daylighting metric on the building layout and compared the new daylighting metric for health and wellbeing with conventional daylighting metrics.
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Cordue, P. L. "Fishing intensity metrics for use in overfishing determination." ICES Journal of Marine Science 69, no. 4 (February 27, 2012): 615–23. http://dx.doi.org/10.1093/icesjms/fss036.
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Abstract Cordue, P. L. 2012. Fishing intensity metrics for use in overfishing determination. – ICES Journal of Marine Science, 69: 615–623. The issue of constructing a technically correct fishing intensity metric from the output of a stock assessment model is considered. Four metrics of annual overall “fishing intensity” are defined. The metrics are applicable to age- or length-structured stock assessment models, which may, or may not, include complex spatial and temporal structure in the population and the fisheries. Two of the metrics are termed “direct” as they are calculated from the model output in the given year. Equivalent annual U is a number-based exploitation rate, and equivalent annual F is an average fishing mortality rate. The other two metrics, equilibrium stock depletion (ESD) and spawning potential ratio (SPR), measure fishing intensity in terms of the potential long-term effect on the stock (via 1–ESD and 1–SPR). The use of the metrics for overfishing determination is illustrated with a simple, spatial, two-fishery model. Summary statistics, which are sometimes used as a measure of fishing intensity, such as total catch over a reference biomass, or a number-weighted F are shown to be technically invalid for overfishing determination. The common approach, for virtual population analysis assessments, of using an average F over a specified age range is also discussed.
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Shao, Shiwei, Mengting Yu, Yimin Huang, Yiheng Wang, Jing Tian, and Chang Ren. "Towards a Core Set of Landscape Metrics of Urban Land Use in Wuhan, China." ISPRS International Journal of Geo-Information 11, no. 5 (April 28, 2022): 281. http://dx.doi.org/10.3390/ijgi11050281.
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In this study, we investigate the urban landscape patterns in Wuhan, China based on the land use data in the vector format. Using the approach of landscape metric analysis, we calculate forty-four vector-based landscape metrics and then reduce redundant ones through a combination of Spearman correlation analysis and factor analysis, in order to extract a core set of characterizing landscape metrics. We find that the urban landscape can be depicted by six factors including the overall shape and diversity, mean proximity, overall area variation, fragmentation variation, elongation variation, and mean shape complexity. After analyzing typical patterns indicated by the core metrics and the spatial distribution of land use patterns, we compare our findings with other studies and discuss how the core metrics coincide and differ.
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Hardiman, Brady, Elizabeth LaRue, Jeff Atkins, Robert Fahey, Franklin Wagner, and Christopher Gough. "Spatial Variation in Canopy Structure across Forest Landscapes." Forests 9, no. 8 (August 3, 2018): 474. http://dx.doi.org/10.3390/f9080474.
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Forest canopy structure (CS) controls many ecosystem functions and is highly variable across landscapes, but the magnitude and scale of this variation is not well understood. We used a portable canopy LiDAR system to characterize variation in five categories of CS along N = 3 transects (140–800 m long) at each of six forested landscapes within the eastern USA. The cumulative coefficient of variation was calculated for subsegments of each transect to determine the point of stability for individual CS metrics. We then quantified the scale at which CS is autocorrelated using Moran’s I in an Incremental Autocorrelation analysis. All CS metrics reached stable values within 300 m but varied substantially within and among forested landscapes. A stable point of 300 m for CS metrics corresponds with the spatial extent that many ecosystem functions are measured and modeled. Additionally, CS metrics were spatially autocorrelated at 40 to 88 m, suggesting that patch scale disturbance or environmental factors drive these patterns. Our study shows CS is heterogeneous across temperate forest landscapes at the scale of 10 s of meters, requiring a resolution of this size for upscaling CS with remote sensing to large spatial scales.
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Andika, I. P. A., M. P. Tambunan, and K. Marko. "Spatial pattern change of land use change in tidal flood area of the coast of Cirebon Regency." IOP Conference Series: Earth and Environmental Science 846, no. 1 (September 1, 2021): 012025. http://dx.doi.org/10.1088/1755-1315/846/1/012025.
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Abstract Tidal flood is one of the threats found in the coastal areas of Cirebon Regency, especially in Pangenan, Gebang and Losari Districts. The changing coastal conditions and the changing land use have worsened the tidal flood. The purpose of this research is to analyse the spatial pattern of land use change in the tidal flood area. This study uses spatial analysis and temporal and spatial metrics. Temporal, spatial analysis is used to see changes in land use in tidal flood areas in 2002, 2009, and 2019, while spatial metrics are used to see these patterns, especially aggregation and diversity. The results of processing show that changes in land use in 2002–2019 were dominated by ponds and irrigated rice fields. The largest land use area in the tidal flood area is in ponds, but the increase has continued to occur in residential and built-up land from 2002 to 2019. Overall, the spatial metric results show that land use fragmentation in the coastal zone of Cirebon Regency in the tidal flood area is increasing. However, the development of land use in the coastal district of Cirebon Regency is low due to tidal flood.
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Andika, I. P. A., M. P. Tambunan, and K. Marko. "Spatial pattern change of land use change in tidal flood area of the coast of Cirebon Regency." IOP Conference Series: Earth and Environmental Science 846, no. 1 (September 1, 2021): 012025. http://dx.doi.org/10.1088/1755-1315/846/1/012025.
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Abstract Tidal flood is one of the threats found in the coastal areas of Cirebon Regency, especially in Pangenan, Gebang and Losari Districts. The changing coastal conditions and the changing land use have worsened the tidal flood. The purpose of this research is to analyse the spatial pattern of land use change in the tidal flood area. This study uses spatial analysis and temporal and spatial metrics. Temporal, spatial analysis is used to see changes in land use in tidal flood areas in 2002, 2009, and 2019, while spatial metrics are used to see these patterns, especially aggregation and diversity. The results of processing show that changes in land use in 2002–2019 were dominated by ponds and irrigated rice fields. The largest land use area in the tidal flood area is in ponds, but the increase has continued to occur in residential and built-up land from 2002 to 2019. Overall, the spatial metric results show that land use fragmentation in the coastal zone of Cirebon Regency in the tidal flood area is increasing. However, the development of land use in the coastal district of Cirebon Regency is low due to tidal flood.
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Chakiryan, Nicholas, Gregory Kimmel, Youngchul Kim, Jonathan Nguyen, Jad Chahoud, Philippe Spiess, Jasreman Dhillon, et al. "85 Spatial heterogeneity of tumor associated macrophages in the tumor immune microenvironment in ccRCC." Journal for ImmunoTherapy of Cancer 8, Suppl 3 (November 2020): A94. http://dx.doi.org/10.1136/jitc-2020-sitc2020.0085.
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BackgroundTumor associated macrophages (TAM) stimulate tumor proliferation and facilitate immune escape via production of immunosuppressive cytokines. We hypothesize that non-random spatial clustering of TAMs within the tumor are associated with poor survival in ccRCC patients.MethodsTumor specimens were obtained from 41 patients with metastatic ccRCC who received immunotherapy (IT). Sections from the tumor core underwent multiplex immunofluorescence staining for CD68, CD163, and CD206. Digital pathologic analysis was used to convert the digital images to spatial point pattern plots (PPP). Ripley’s K function, the current standard metric for spatial heterogeneity, was utilized. Novel metrics were developed using a probability density function (PDF) for distances between cells, assuming that cells can be located anywhere with equal probability. Empirical histograms were generated from the PPPs. Deviation from the PDF demonstrates a non-random distribution. Deviations were quantified with the Kolmogorov-Smirnov (KS) test and Cramér-von Mises (CVM) criterion. Overall survival (OS) was assessed between groups stratified by the median value for each metric using Kaplan-Meier and log-rank analysis. Figure 1A.Results75 slides were analyzed from the 41 patients. The three metrics for measuring spatial heterogeneity had moderate and statistically significant correlation with each other (Spearman’s R: Ripley/KS=0.68, p<0.01; Ripley/CVM=0.54, p<0.01; KS/CVM=0.47, p<0.01; figure 1B). Using CVM, increasingly non-random distribution of the Tumor-CD68+ cell relationship was associated with worse OS (p<0.01, figure 1C), and increasingly non-random distribution of CD163+ cells suggested an association with worse OS without reaching statistical significance (p=0.06, figure 1C). No statistically significant associations were identified using the KS or Ripley’s K metrics.Abstract 85 Figure 1ConclusionsWe describe CVM and KS as novel metrics for measuring spatial heterogeneity of immune cells. Increased spatial heterogeneity of CD68+ TAMs and tumor cells was associated with worse OS in patients with metastatic ccRCC who received IT. These findings corroborate prior reports of TAMs eliciting an immunosuppressive effect on the tumor-immune microenvironment, and demonstrate the novel finding of a clinically significant effect of TAM spatial clustering on OS.
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Wasserman, Tzeidle N., Andrew J. Sánchez Meador, and Amy E. M. Waltz. "Grain and Extent Considerations Are Integral for Monitoring Landscape-Scale Desired Conditions in Fire-Adapted Forests." Forests 10, no. 6 (May 29, 2019): 465. http://dx.doi.org/10.3390/f10060465.
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Remotely-sensed data are commonly used to evaluate forest metrics, such as canopy cover, to assess change detection, and to inform land management planning. Often, canopy cover is measured only at the scale of the spatial data product used in the analysis, and there is a mismatch between the management question and the scale of the data. We compared four readily available remotely sensed landscape data products— Light detection and ranging (LiDAR), Landsat-8, Sentinel-2, and National Agriculture Imagery Program (NAIP) imagery —at different spatial grains and multiple extents to assess their consistency and efficacy for quantifying key landscape characteristics of forest canopy patches and sensitivity to change. We examined landscape-scale patterns of forest canopy cover across three landscapes in northern Arizona and assessed their performance using six landscape metrics. Changes in grain and extent affect canopy cover patch metrics and the inferences that can be made from each data product. Overall data products performed differently across landscape metrics. When performing analyses and choosing data layers, it is essential to match the scale of the data product to the management question and understand the limitations inherent in using canopy cover as a stand-alone metric.
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Firmansyah, F., A. Pamungkas, and K. D. Larasati. "Spatial pattern analysis using spatial metrics: a case study in Surabaya, Indonesia." IOP Conference Series: Earth and Environmental Science 202 (November 27, 2018): 012018. http://dx.doi.org/10.1088/1755-1315/202/1/012018.
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Demirel, Mehmet C., Juliane Mai, Gorka Mendiguren, Julian Koch, Luis Samaniego, and Simon Stisen. "Combining satellite data and appropriate objective functions for improved spatial pattern performance of a distributed hydrologic model." Hydrology and Earth System Sciences 22, no. 2 (February 20, 2018): 1299–315. http://dx.doi.org/10.5194/hess-22-1299-2018.
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Abstract. Satellite-based earth observations offer great opportunities to improve spatial model predictions by means of spatial-pattern-oriented model evaluations. In this study, observed spatial patterns of actual evapotranspiration (AET) are utilised for spatial model calibration tailored to target the pattern performance of the model. The proposed calibration framework combines temporally aggregated observed spatial patterns with a new spatial performance metric and a flexible spatial parameterisation scheme. The mesoscale hydrologic model (mHM) is used to simulate streamflow and AET and has been selected due to its soil parameter distribution approach based on pedo-transfer functions and the build in multi-scale parameter regionalisation. In addition two new spatial parameter distribution options have been incorporated in the model in order to increase the flexibility of root fraction coefficient and potential evapotranspiration correction parameterisations, based on soil type and vegetation density. These parameterisations are utilised as they are most relevant for simulated AET patterns from the hydrologic model. Due to the fundamental challenges encountered when evaluating spatial pattern performance using standard metrics, we developed a simple but highly discriminative spatial metric, i.e. one comprised of three easily interpretable components measuring co-location, variation and distribution of the spatial data. The study shows that with flexible spatial model parameterisation used in combination with the appropriate objective functions, the simulated spatial patterns of actual evapotranspiration become substantially more similar to the satellite-based estimates. Overall 26 parameters are identified for calibration through a sequential screening approach based on a combination of streamflow and spatial pattern metrics. The robustness of the calibrations is tested using an ensemble of nine calibrations based on different seed numbers using the shuffled complex evolution optimiser. The calibration results reveal a limited trade-off between streamflow dynamics and spatial patterns illustrating the benefit of combining separate observation types and objective functions. At the same time, the simulated spatial patterns of AET significantly improved when an objective function based on observed AET patterns and a novel spatial performance metric compared to traditional streamflow-only calibration were included. Since the overall water balance is usually a crucial goal in hydrologic modelling, spatial-pattern-oriented optimisation should always be accompanied by traditional discharge measurements. In such a multi-objective framework, the current study promotes the use of a novel bias-insensitive spatial pattern metric, which exploits the key information contained in the observed patterns while allowing the water balance to be informed by discharge observations.
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Gábrová, Lenka. "Comparison between Dynamic and Static Metrics for Daylight Evaluation in the Case of Obstructed Buildings." Applied Mechanics and Materials 861 (December 2016): 477–84. http://dx.doi.org/10.4028/www.scientific.net/amm.861.477.
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Daylight in buildings can be evaluated using dynamic and static daylight metrics. The daylight factor is a static daylight metric which evaluates daylight conditions under the overcast sky model according to the International Commission on Illumination. However, the dynamic daylight metrics (e.g. daylight autonomy, spatial daylight autonomy, useful daylight illuminance) can be more complex evaluation criteria because they are based on annual daylight illuminance data for a building site. While the daylight factor value depends only on a room geometry, optical properties of surfaces and positioning of daylight obstructions, the dynamic daylight metrics also include an effect of a building location, window orientation or building occupancy pattern. The article deals with a comparison of a daylight evaluation using dynamic and static daylight metrics in the case of buildings whose daylight is obstructed by external barriers.
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Keizer-Vlek, Hanneke E., Piet F. M. Verdonschot, Ralf C. M. Verdonschot, and Paul W. Goedhart. "Quantifying spatial and temporal variability of macroinvertebrate metrics." Ecological Indicators 23 (December 2012): 384–93. http://dx.doi.org/10.1016/j.ecolind.2012.04.025.
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Triantakonstantis, Dimitrios, and Demetris Stathakis. "Examining urban sprawl in Europe using spatial metrics." Geocarto International 30, no. 10 (April 2015): 1092–112. http://dx.doi.org/10.1080/10106049.2015.1027289.
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Humphreys, Macartan, and Michael Laver. "Spatial Models, Cognitive Metrics, and Majority Rule Equilibria." British Journal of Political Science 40, no. 1 (November 30, 2009): 11–30. http://dx.doi.org/10.1017/s0007123409990263.
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Long-standing results demonstrate that, if policy choices are defined in spaces with more than one dimension, majority-rule equilibrium fails to exist for a general class of smooth preference profiles. This article shows that if agents perceive political similarity and difference in ‘city block’ terms, then the dimension-by-dimension median can be a majority-rule equilibrium even in spaces with an arbitrarily large number of dimensions and it provides necessary and sufficient conditions for the existence of such an equilibrium. This is important because city block preferences accord more closely with empirical research on human perception than do many smooth preferences. It implies that, if empirical research findings on human perceptions of similarity and difference extend also to perceptions ofpoliticalsimilarity and difference, then the possibility of equilibrium under majority rule re-emerges.
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Barrell, Jeffrey, and Jon Grant. "High-resolution, low-altitude aerial photography in physical geography." Progress in Physical Geography: Earth and Environment 39, no. 4 (May 5, 2015): 440–59. http://dx.doi.org/10.1177/0309133315578943.
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Intertidal landscapes are highly complex and dynamic habitats that exhibit variability over a range of spatial and temporal scales. The spatial arrangement of structure-forming biogenic features such as seagrasses and bivalves influences ecosystem function and the provision of important ecosystem services, though quantification and monitoring of intertidal landscape structure has been hindered by challenges collecting spatial data in the coastal zone. In this study, an intertidal landscape mosaic of eelgrass ( Zostera marina) and blue mussels ( Mytilus edulis) was observed using low-altitude aerial photography from a balloon-mounted digital camera platform. Imagery representing seagrass-bivalve landscape structure was classified and analysed using multiple metrics of landscape composition and configuration at the patch scale and the landscape scale. Patch-scale imagery was compared to a previously collected dataset in order to track temporal changes in seagrass patch metrics over a 26-month period. Seagrass and bivalve patches exhibited distinct spatial patterning at different spatial scales. At the patch scale, the change in seagrass metrics was consistent with patch border expansion at the expense of patch density and integrity. These methods demonstrate a novel approach for collecting high-resolution spatial data that could also be valuable to physical geographers dealing with similar fine-scale landscapes. The application of spatial metrics at multiple spatial scales quantified elements of the configuration and composition of a seagrass-bivalve habitat mosaic and allowed for the tracking of patch metrics through time to depict landscape change. Continued development of landscape metrics within intertidal habitats will increase understanding of the ecological function of these areas with benefits to management and monitoring of ecosystem health.
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Abd-Elrahman, Amr, Zhen Guan, Cheryl Dalid, Vance Whitaker, Katherine Britt, Benjamin Wilkinson, and Ali Gonzalez. "Automated Canopy Delineation and Size Metrics Extraction for Strawberry Dry Weight Modeling Using Raster Analysis of High-Resolution Imagery." Remote Sensing 12, no. 21 (November 5, 2020): 3632. http://dx.doi.org/10.3390/rs12213632.
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Capturing high spatial resolution imagery is becoming a standard operation in many agricultural applications. The increased capacity for image capture necessitates corresponding advances in analysis algorithms. This study introduces automated raster geoprocessing methods to automatically extract strawberry (Fragaria × ananassa) canopy size metrics using raster image analysis and utilize the extracted metrics in statistical modeling of strawberry dry weight. Automated canopy delineation and canopy size metrics extraction models were developed and implemented using ArcMap software v 10.7 and made available by the authors. The workflows were demonstrated using high spatial resolution (1 mm resolution) orthoimages and digital surface models (2 mm) of 34 strawberry plots (each containing 17 different plant genotypes) planted on raised beds. The images were captured on a weekly basis throughout the strawberry growing season (16 weeks) between early November and late February. The results of extracting four canopy size metrics (area, volume, average height, and height standard deviation) using automatically delineated and visually interpreted canopies were compared. The trends observed in the differences between canopy metrics extracted using the automatically delineated and visually interpreted canopies showed no significant differences. The R2 values of the models were 0.77 and 0.76 for the two datasets and the leave-one-out (LOO) cross validation root mean square error (RMSE) of the two models were 9.2 g and 9.4 g, respectively. The results show the feasibility of using automated methods for canopy delineation and canopy metric extraction to support plant phenotyping applications.
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Song, Yu, Xiaodong Song, and Guofan Shao. "Effects of Green Space Patterns on Urban Thermal Environment at Multiple Spatial–Temporal Scales." Sustainability 12, no. 17 (August 24, 2020): 6850. http://dx.doi.org/10.3390/su12176850.
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Land use/land cover (LULC) pattern change due to human activity is one of the key components of regional and global climate change drivers. Urban green space plays a critical role in regulating urban thermal environment, and its cooling effect has received widespread attention in urban heat island (UHI) related studies. To fully understand the effects of the landscape pattern of an urban green space in regulating the urban thermal environment, it is necessary to further study the thermal effects of the landscape pattern of the urban green space and its characteristics under varied spatial–temporal scales. In this paper, we took the urban core area of Hangzhou City as the study area and analyzed the relationships between the landscape metrics of the urban green space and land surface temperature (LST) under varied spatial scales by using correlation analysis and redundancy analysis (RDA) methods. Multi-temporal Landsat 8 thermal infrared sensor data were used to retrieve the spatial and temporal dynamics of LSTs in four consecutive seasons, and the land use classification was interpreted using SPOT (Systeme Probatoire d’Observation de la Terre) satellite imagery. The results showed that landscape dominance metrics—e.g., percentage of landscape (PLAND) and largest patch index (LPI)—were the most influential factors on urban LST. The spatial configuration of urban landscape, as represented by the fragmentation and aggregation and connectedness, also showed significant effects on LST. Furthermore, landscape pattern metrics had varied spatial scale effects on LST. Specifically, the landscape dominance metrics of urban forest showed an increased influence on LST as the spatial scale increased, while for urban water, the trend was opposite. These findings might have some practical significance for urban planning about how to spatially arrange urban green space to alleviate UHI at local and regional scales.
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Mudau, Naledzani, and Paidamwoyo Mhangara. "Assessment of Spatial Patterns of Backyard Shacks Using Landscape Metrics." Drones 7, no. 9 (September 1, 2023): 561. http://dx.doi.org/10.3390/drones7090561.
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Urban informality in developing economies like South Africa takes two forms: freestanding shacks are built in informal settlements, and backyard shacks are built in the yard of a formal house. The latter is evident in established townships around South African cities. In contrast to freestanding shacks, the number of backyard shacks has increased significantly in recent years. The study assessed the spatial patterns of backyard shacks in a formal settlement containing low-cost government houses (LCHs) using Unmanned Aerial Vehicle (UAV) products and landscape metrics. The backyard shacks were mapped using Object-Based Image Analysis (OBIA), which uses height information, vegetation index, and radiometric values. We assessed the effectiveness of rule-based and Random Forest (RF) OBIA techniques in detecting formal and informal structures. Informal structures were further classified as backyard shacks using spatial analysis. The spatial patterns of backyard shacks were assessed using eight shapes, aggregation, and landscape metrics. The analysis of the shape metrics shows that the backyard shacks are primarily square, as confirmed by a higher shape index value and a lower fractional dimension index value. The contiguity index of backyard shack patches is 0.6. The values of the shape metrics of backyard shacks were almost the same as those of formal and informal dwelling structures. The values of the assessed aggregation metrics of backyard shacks were more distinct from formal and informal structures compared with the shape metrics. The aggregation metrics show that the backyard shacks are less connected, less dense, and more isolated from each other compared with formal and freestanding shacks. The Shannon’s Diversity Index and Simpson’s Evenness Index values of informal settlements and formal areas with backyard shacks are almost the same. The results achieved in this study can be used to understand and manage informality in formal settlements.