3,294 research outputs found
Narratives from the margins, Revised and enlarged edition
The essays in this book discuss a range of issues affecting the socio-economic and cultural life of adivasis and explore the long-term continuities and discontinuities between different political regimes
Abnormal Trajectory-Gap Detection: A Summary (Short Paper)
Given trajectories with gaps (i.e., missing data), we investigate algorithms to identify abnormal gaps for testing possible hypotheses of anomalous regions. Here, an abnormal gap within a trajectory is defined as an area where a given moving object did not report its location, but other moving objects did periodically. The problem is important due to its societal applications, such as improving maritime safety and regulatory enforcement for global security concerns such as illegal fishing, illegal oil transfer, and trans-shipments. The problem is challenging due to the difficulty of interpreting missing data within a trajectory gap, and the high computational cost of detecting gaps in such a large volume of location data proves computationally very expensive. The current literature assumes linear interpolation within gaps, which may not be able to detect abnormal gaps since objects within a given region may have traveled away from their shortest path. To overcome this limitation, we propose an abnormal gap detection (AGD) algorithm that leverages the concepts of a space-time prism model where we assume space-time interpolation. We then propose a refined memoized abnormal gap detection (Memo-AGD) algorithm that reduces comparison operations. We validated both algorithms using synthetic and real-world data. The results show that abnormal gaps detected by our algorithms give better estimates of abnormality than linear interpolation and can be used for further investigation from the human analysts
Analyzing Trajectory Gaps for Possible Rendezvous: A Summary of Results
Given trajectory data with gaps, we investigate methods to identify possible rendezvous regions. Societal applications include improving maritime safety and regulations. The challenges come from two aspects. If trajectory data are not available around the rendezvous then either linear or shortest-path interpolation may fail to detect the possible rendezvous. Furthermore, the problem is computationally expensive due to the large number of gaps and associated trajectories. In this paper, we first use the plane sweep algorithm as a baseline. Then we propose a new filtering framework using the concept of a space-time grid. Experimental results and case study on real-world maritime trajectory data show that the proposed approach substantially improves the Area Pruning Efficiency over the baseline technique
Reducing False Discoveries in Statistically-Significant Regional-Colocation Mining: A Summary of Results
Given a set S of spatial feature types, its feature instances, a study area, and a neighbor relationship, the goal is to find pairs such that C is a statistically significant regional-colocation pattern in r_{g}. This problem is important for applications in various domains including ecology, economics, and sociology. The problem is computationally challenging due to the exponential number of regional colocation patterns and candidate regions. Previously, we proposed a miner [Subhankar et. al, 2022] that finds statistically significant regional colocation patterns. However, the numerous simultaneous statistical inferences raise the risk of false discoveries (also known as the multiple comparisons problem) and carry a high computational cost. We propose a novel algorithm, namely, multiple comparisons regional colocation miner (MultComp-RCM) which uses a Bonferroni correction. Theoretical analysis, experimental evaluation, and case study results show that the proposed method reduces both the false discovery rate and computational cost
Towards Statistically Significant Taxonomy Aware Co-Location Pattern Detection (Short Paper)
Given a collection of Boolean spatial feature types, their instances, a neighborhood relation (e.g., proximity), and a hierarchical taxonomy of the feature types, the goal is to find the subsets of feature types or their parents whose spatial interaction is statistically significant. This problem is for taxonomy-reliant applications such as ecology (e.g., finding new symbiotic relationships across the food chain), spatial pathology (e.g., immunotherapy for cancer), retail, etc. The problem is computationally challenging due to the exponential number of candidate co-location patterns generated by the taxonomy. Most approaches for co-location pattern detection overlook the hierarchical relationships among spatial features, and the statistical significance of the detected patterns is not always considered, leading to potential false discoveries. This paper introduces two methods for incorporating taxonomies and assessing the statistical significance of co-location patterns. The baseline approach iteratively checks the significance of co-locations between leaf nodes or their ancestors in the taxonomy. Using the Benjamini-Hochberg procedure, an advanced approach is proposed to control the false discovery rate. This approach effectively reduces the risk of false discoveries while maintaining the power to detect true co-location patterns. Experimental evaluation and case study results show the effectiveness of the approach
Supplemental Material, VanDijketal_SI_SpatialVariationInGroundwaterStresses - Spatial variation of groundwater response to multiple drivers in a depleting alluvial aquifer system, northwestern India
Supplemental Material, VanDijketal_SI_SpatialVariationInGroundwaterStresses for Spatial variation of groundwater response to multiple drivers in a depleting alluvial aquifer system, northwestern India by Wout M van Dijk, Alexander L Densmore, Christopher R Jackson, Jonathan D Mackay, Suneel K Joshi, Rajiv Sinha, Shashank Shekhar and Sanjeev Gupta in Progress in Physical Geography: Earth and Environment</p
Data for Gupta et al., "Estimating the Meridional Extent of Adiabatic Mixing in the Stratosphere using Age-of-Air", JGR:Atmospheres,
Model data and post-processed data supporting the creation of the manuscript "Estimating the Meridional Extent of Adiabatic Mixing in the Stratosphere using Age-of-Air" submitted to JGR:Atmospheres in August 2022.
1) The netCDF files created through post-processing of full model data in FORTRAN are shared in the /data/ directory. These file contains the zonal mean circulation statistics based on Gupta et al. (2020), age-of-air transport diagnostics based on Linz et al. (2021), and the novel \Gamma-\Theta circulation streamfunction introduced in this study. The /data/ directory also contains MATLAB .mat data files for the transport diagnostics obtained from WACCM. 150 days of actual GFDL-FV3 model data in the northern hemisphere, between 0.1 hPa-500 hPa pressure levels is also provided to support external computations and validation.
2) The Jupyter notebook used for final computation and figures production is provided in .ipynb, .html and .pdf formats in /code/. All the files referred to in the notebook are stored in the /data/ directory.
Corresponding author : Aman Gupta, [email protected], [email protected], [email protected]
Chapter 1, Introduction
The adivasi world figured in official perceptions as the backdrop of the counter-insurgency measures of the colonial state and the adivasi was portrayed as a savage, whether ‘criminal’ and wreaking terror in the countryside, or ‘noble’ and living a life of Arcadian simplicity in an egalitarian society. Through such models, British administrators sought to justify their presence and portray themselves as the protectors of life and security in the region. In course of the nineteenth century, colonial ethnographers came to rely largely on the ‘scientific’ criteria of ethnology—‘physical character’, ‘language’, ‘civilization’ and ‘religion’. Nonetheless, there was no fixed colonial ‘tribal’ policy, nor was there a
single set of ideas concerning tribes, generated either by the colonial power itself or arising out of a process of interaction and adaptation. Instead, we find that several, often contradictory policies towards the indigenous people emerged in course of the nineteenth and twentieth centuries. These are illustrated in the contributions to this volume
Corrigendum: Capital Inflows and House Prices: Aggregate and Regional Evidence from China
In the paper ‘Capital Inflows and House Prices: Aggregate and Regional Evidence from China’ by H. An, et al., printed in the December 2016 issue, there was a missing acknowledgement section for funding resources.
On page 451, the acknowledgement section should appear after the corresponding information as:
“Correspondence: Rakesh Gupta, Department of Accounting, Finance and Economics, Griffith Business School, Griffith University, Nathan Campus QLD 4111. [email protected]
*This work was financially supported by the Humanities and Social Science Foundation of Ministry of Education of China (16YJA790001).”
The author apologises for this error and any confusion it may have caused.No Full Tex
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