spatial entropy
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Land ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1368
Author(s):  
Pietro De Marinis ◽  
Samuele De Petris ◽  
Filippo Sarvia ◽  
Giacinto Manfron ◽  
Evelyn Joan Momo ◽  
...  

In the eastern Democratic Republic of Congo, agriculture represents the most important economic sector, and land control can be considered a perpetual source of conflict. Knowledge of the existing production system distribution is fundamental for both informing national land tenure reforms and guiding more effective agricultural development interventions. The present paper focuses on existing agricultural production systems in Katoyi collectivity, Masisi territory, where returning Internally and Externally Displaced People are resettling. We aim to define a repeatable methodology for building evidence-based and updated knowledge concerning the spatial distribution of the two existing production systems: subsistence-oriented agriculture (SOA) and business-oriented agriculture (BOA). To this aim, we used a supervised object-based classification approach on remotely sensed Sentinel-2 imagery to classify land cover. To classify production systems further within the “agriculture” and “pasture” land use classes, binary classification based on an entropy value threshold was performed. An iterative approach was adopted to define the final HNDVI threshold that minimised commission and omission errors and maximised overall accuracy and class separability. The methodology achieved acceptable observed accuracy (OA equal to 80–90% respectively for agricultural and pasture areas) in the assessment. SOA and BOA respectively covered 24.4 and 75.6% of the collectivity area (34606 ha). The results conclude that land use and entropy analysis can draw an updated picture of existing land distribution among different production systems, supporting better-adapted intervention strategies in development cooperation and pro-poor agrarian land tenure reforms in conflict-ridden landscapes.


2021 ◽  
Vol 16 (4) ◽  
pp. 83-96
Author(s):  
S.Yu. Kornienko ◽  

Statement of the problem. The problems of the article are addressed to the methods of cultural development of the vast Siberian steppes in Russian modernism, to the methods of overcoming cultural entropy. The purpose of the article is to describe the parameters of the “steppe” texts by M. Tsvetaeva and K. Balmont, to identify their cultural genealogy. Review of scientific literature on the problem is associated with solving specific problems: identifying ways of authorizing the Siberian text in the poetics of a particular author (works by A. Smith, E. Korkina, and V. Marosha). Research results. The article is devoted to the Siberian texts by K. Balmont and M. Tsvetaeva. In the collection of works by Balmont entitled “Blue Horseshoe. Poems about Siberia”, the perception of the Siberian steppes is built around the concepts of “distance”, “width”, and “freedom”, characteristic of Balmont’s poetry, in principle. In Tsvetaeva’s poem “Siberia”, the steppe theme appears twice: in the exposition of the poem, and also in the second part (the image of the Barabinsk steppe). The sources of Tsvetaeva’s steppe imagery can be considered her individual perception Blok’s “Scythianism”, her direct empirical experience of experiencing the Crimean steppes, as well as her keen interest in the Eurasian theory at the time of writing the poem. Conclusions. Spatial entropy does not become an obstacle for an artist of the modernist formation in the cultural development of space. Each poet creates his own image of the Siberian steppes, based on the available poetic tools, synthesizing creative methods.


2021 ◽  
Vol 11 ◽  
Author(s):  
Gedmante Radziuviene ◽  
Allan Rasmusson ◽  
Renaldas Augulis ◽  
Ruta Barbora Grineviciute ◽  
Dovile Zilenaite ◽  
...  

Breast cancer (BC) categorized as human epidermal growth factor receptor 2 (HER2) borderline [2+ by immunohistochemistry (IHC 2+)] presents challenges for the testing, frequently obscured by intratumoral heterogeneity (ITH). This leads to difficulties in therapy decisions. We aimed to establish prognostic models of overall survival (OS) of these patients, which take into account spatial aspects of ITH and tumor microenvironment by using hexagonal tiling analytics of digital image analysis (DIA). In particular, we assessed the prognostic value of Immunogradient indicators at the tumor–stroma interface zone (IZ) as a feature of antitumor immune response. Surgical excision samples stained for estrogen receptor (ER), progesterone receptor (PR), Ki67, HER2, and CD8 from 275 patients with HER2 IHC 2+ invasive ductal BC were used in the study. DIA outputs were subsampled by HexT for ITH quantification and tumor microenvironment extraction for Immunogradient indicators. Multiple Cox regression revealed HER2 membrane completeness (HER2 MC) (HR: 0.18, p = 0.0007), its spatial entropy (HR: 0.37, p = 0.0341), and ER contrast (HR: 0.21, p = 0.0449) as independent predictors of better OS, with worse OS predicted by pT status (HR: 6.04, p = 0.0014) in the HER2 non-amplified patients. In the HER2-amplified patients, HER2 MC contrast (HR: 0.35, p = 0.0367) and CEP17 copy number (HR: 0.19, p = 0.0035) were independent predictors of better OS along with worse OS predicted by pN status (HR: 4.75, p = 0.0018). In the non-amplified tumors, three Immunogradient indicators provided the independent prognostic value: CD8 density in the tumor aspect of the IZ and CD8 center of mass were associated with better OS (HR: 0.23, p = 0.0079 and 0.14, p = 0.0014, respectively), and CD8 density variance along the tumor edge predicted worse OS (HR: 9.45, p = 0.0002). Combining these three computational indicators of the CD8 cell spatial distribution within the tumor microenvironment augmented prognostic stratification of the patients. In the HER2-amplified group, CD8 cell density in the tumor aspect of the IZ was the only independent immune response feature to predict better OS (HR: 0.22, p = 0.0047). In conclusion, we present novel prognostic models, based on computational ITH and Immunogradient indicators of the IHC biomarkers, in HER2 IHC 2+ BC patients.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Aarón Maturana-Candelas ◽  
Carlos Gómez ◽  
Jesús Poza ◽  
Víctor Rodríguez-González ◽  
Vìctor Gutiérrez-de Pablo ◽  
...  

AbstractPICALM and CLU genes have been linked to alterations in brain biochemical processes that may have an impact on Alzheimer’s disease (AD) development and neurophysiological dynamics. The aim of this study is to analyze the relationship between the electroencephalographic (EEG) activity and the PICALM and CLU alleles described as conferring risk or protective effects on AD patients and healthy controls. For this purpose, EEG activity was acquired from: 18 AD patients and 12 controls carrying risk alleles of both PICALM and CLU genes, and 35 AD patients and 12 controls carrying both protective alleles. Relative power (RP) in the conventional EEG frequency bands (delta, theta, alpha, beta, and gamma) was computed to quantify the brain activity at source level. In addition, spatial entropy (SE) was calculated in each band to characterize the regional distribution of the RP values throughout the brain. Statistically significant differences in global RP and SE at beta band (p-values < 0.05, Mann–Whitney U-test) were found between genotypes in the AD group. Furthermore, RP showed statistically significant differences in 58 cortical regions out of the 68 analyzed in AD. No statistically significant differences were found in the control group at any frequency band. Our results suggest that PICALM and CLU AD-inducing genotypes are involved in physiological processes related to disruption in beta power, which may be associated with physiological disturbances such as alterations in beta-amyloid and neurotransmitter metabolism.


Symmetry ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1446
Author(s):  
Zhouyan He ◽  
Yang Song ◽  
Caiming Zhong ◽  
Li Li

The multi-exposure fusion (MEF) technique provides humans a new opportunity for natural scene representation, and the related quality assessment issues are urgent to be considered for validating the effectiveness of these techniques. In this paper, a curvature and entropy statistics-based blind MEF image quality assessment (CE-BMIQA) method is proposed to perceive the quality degradation objectively. The transformation process from multiple images with different exposure levels to the final MEF image leads to the loss of structure and detail information, so that the related curvature statistics features and entropy statistics features are utilized to portray the above distortion presentation. The former features are extracted from the histogram statistics of surface type map calculated by mean curvature and Gaussian curvature of MEF image. Moreover, contrast energy weighting is attached to consider the contrast variation of the MEF image. The latter features refer to spatial entropy and spectral entropy. All extracted features based on a multi-scale scheme are aggregated by training the quality regression model via random forest. Since the MEF image and its feature representation are spatially symmetric in physics, the final prediction quality is symmetric to and representative of the image distortion. Experimental results on a public MEF image database demonstrate that the proposed CE-BMIQA method achieves more outstanding performance than the state-of-the-art blind image quality assessment ones.


Entropy ◽  
2021 ◽  
Vol 23 (7) ◽  
pp. 799
Author(s):  
Javier Galeano ◽  
Miguel-Ángel Gomez ◽  
Fernando Rivas ◽  
Javier M. Buldú

The aim of the current study was twofold: (i) to investigate the distribution of the strike positions of badminton players while quantifying the corresponding standard entropy and using an alternative metric (spatial entropy) related to winning and losing points and random positions; and (ii) to evaluate the standard entropy of the receiving positions. With the datasets of 259 badminton matches, we focused on the positions of players’ strokes and the outcome of each point. First, we identified those regions of the court from which hits were most likely to be struck. Second, we computed the standard entropy of stroke positions, and then the spatial entropy, which also considers the order and clustering of the hitting locations in a two-dimensional Euclidean space. Both entropy quantifiers revealed high uncertainty in the striking position; however, specific court locations (i.e., the four corners) are preferred over the rest. When the outcome of each point was taken into account, we observed that the hitting patterns with lower entropy were associated with higher probabilities of winning points. On the contrary, players striking from more random positions were more prone to losing the points.


Author(s):  
Xiaomeng Liu ◽  
Lars Loetgering ◽  
Anne de Beurs ◽  
Mengqi Du ◽  
Patrick Konold ◽  
...  

Author(s):  
Linda Altieri ◽  
Daniela Cocchi

This work presents a study on the urban configuration of a number of Italian metropolitan areas and their development over time, with the aim of evaluating the size and shape of urban areas expansion. Raster data are used, produced by the European Environmental Agency within the COoRdination of INformation on the Environment land cover project. The study is based on a version of spatial entropy measures proposed and validated by a recent series of papers, aimed at the evaluation of spatial data heterogeneity; the methods assess the efficiency of the spatial configuration of urban areas. An innovative combination of two entropy measures is the tool for evaluating the urban development in Italy. Results allow both conclusive comments about each metropolitan area and comparisons across areas over space and time.


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