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Some of the extreme space weather events like the geomagnetic storm of 17–18 March 2015 have produced dramatic effects on low-latitude ionosphere as reported in various studies. Similarly, some of the extreme storms are studied to emphasize the anomalous deviations in ionospheric delay; however, the effects of excess ionospheric delay on GPS-based positioning are rarely reported from India. This paper presents a robust analysis including estimation of GPS receiver position during 6 major geomagnetic storms using dual frequency GPS signals in L1 and L2 bands. Epoch-wise solution estimates are computed using precise orbit SP3 files for satellite orbit and clock corrections and receiver specific differential code biases are obtained from IGS-CODE center. A range domain Kalman filter has also been developed to smooth the 30 s sampled code pseudorange using carrier phase data and resolve the initial ambiguity. Then, the precise positioning residuals are estimated in two different cases of ionospheric corrected and ionospheric uncorrected error models. We then compare the results with ionospheric corrected position estimates to finally obtain the effect of excess daytime ionospheric variations during main phase of some extreme geomagnetic storms. Results from 5 GPS receivers located within 77°–80° E longitude sector are obtained for two 2-hour windows covering local noon during 6 storms including the St. Patrick's Day storm. The effect of severity of the storms and their impact on static precise positioning are brought out by comparing the results with performance on a quiet day. It is found that the magnitude of error in estimated altitude exhibits maximum deviations due to ionospheric variations during storms, and the dip latitude of station is important in terms of magnitude of ionospheric error in positioning over the equatorial ionization anomaly region. [ABSTRACT FROM AUTHOR]

Scomberomorus guttatus has been subjected to a series of synonym assignations over the years. Its taxonomy has been mired with ambiguities due to the greater‐than‐average morphological variations observed in samples from different regions. An integrated taxonomic revision with molecular support indicated that the species that was thought to be a single entity, in reality, is a complex of three distinct species. They are morphologically distinct with respect to the body depth and elongation, cephalic morphometry, and meristic characteristics. Otolith morphometry and phylogenetic evidence further established the taxonomic divergence within the spotted seerfish complex. The phylogenetic characteristic as indicated by the mitochondrial Cytochrome c Oxidase subunit I (COI) sequence unveiled that S. guttatus had a high intraspecific divergence of 11.1% from its two identical congeners and a divergence of 2.34% between the congeners, indicating scope for categorizing them as separate species. Based on the morphological and molecular evidence, S. guttatus is redescribed; the senior synonym Scomberomorus leopardus is resurrected as a valid species; and a new species Scomberomorus avirostrus n. sp. is described with keys for species distinction. [ABSTRACT FROM AUTHOR]

We describe the [somewhat tedious] process of digitising from a 1955 report that lists over 1000 vertical deflections in India and some surrounding countries. It involved error-checking with closed-loop tests and resolution of an ambiguity surrounding the meridional vertical deflection at the Kalianpur origin of the datum. We transformed these Kalianpur coordinates to geodetic coordinates on geocentric datum to compute absolute vertical deflections. However, due to many changes to the Everest spheroid due to different feet to metre conversions and readjustments of the Kalianpur datum, we were restricted to using the abridged Molodensky transformation parameters for the 1975 Kalianpur datum and Everest 1956 spheroid based on only seven common points from the WGS84 technical manual. We compared these transformed absolute vertical deflections with EGM2008 and GGMplus (for both models: meridional standard deviation: ∼±2″; prime vertical standard deviation: ∼±3″), showing that the effort of digitisation and scrutiny of historical geodetic data is indeed worthwhile. [ABSTRACT FROM AUTHOR]

In India, most of the Science and Technology resources available are in English. Developing an Automatic Language Translation Engine from English (source language) to Tamil (target language) is very essential for the people who need to get technical resources in their native language. The challenges in designing such engines using Natural Language Processing (NLP) tools include Lexical, Structural, and Syntax level ambiguity. To solve these challenges, the development of a Part- Of-Speech (POS) tagger is essential. The Verb-Framed languages like Tamil, Japanese, and many languages in Romance, Semitic, and Mayan languages families have high morphological richness but lack either a large volume of annotated corpora or manually constructed linguistic resources for building POS tagger. Moreover, the Tamil Language has a low resource, high word sense ambiguity, and word-free order form giving rise to challenges in designing Tamil POS taggers. In this paper, we postulate a Hybrid POS tagger algorithm for Tamil Language using Cross-Lingual Transformation Learning Techniques. It is a novel Mining-based algorithm (MT), which finds equivalent words of Tamil in English on less volume of English- Tamil bilingual unannotated parallel corpus. To enhance the performance of MT, we developed Tamil language-specific auxiliary algorithms such as Keyword-based tagging algorithm (KT) and Verb pattern-based tagging algorithm (VT). We also developed a Unique pair occurrence-tagging algorithm (UT) to find the one-time occurrence of Tamil-English pair words. Our experiments show that by improving Context-based Bilingual Corpus to Bilingual parallel corpus and after leaving onetime occurrence words, the proposed Hybrid POS tagger can predict 81.15% words, with 73.51% accuracy and 90.50% precision. Evaluations prove our algorithms can generate language resources, which can improve the performance of NLP tasks in Tamil. [ABSTRACT FROM AUTHOR]

Increasing environmental crises due to climate change calls for bridging the research and operational logics of spatial planning and humanitarian response. This article explores how long-term spatial planning and short-term humanitarian responses relate to three facets of uncertainty that are particularly relevant in developmental contexts, namely epistemic uncertainty, ontic uncertainty, and ambiguity. The authors explore these facets through a case study of uncertainty, that of unexpected monsoon floods in 2018 and 2019 in Wayanad, a peri-urban hill district in Kerala, India. Through the case, they show that compounded uncertainty leads to ambiguity in action, but that this ambiguity can be ameliorated by a contextualised contingency planning approach. The authors conclude the article by outlining the approach in spatial planning that prioritises flexible and adaptable decision-making to enhance iterative organisational learning and action, as well as cross-sectoral dialogue to deal with uncertainty. [ABSTRACT FROM AUTHOR]

The overemphasis in recent anthropological scholarship on self‐cultivation through normative discourses has resulted in largely neglecting explorative discourses that have also been key to the formation of religious subjectivities. The relationship between these discourses has tended to be that of ambiguity, given that various groups have sought to establish clear boundaries regarding what is morally acceptable. In this article, I look at how ambiguity is played out in a small town in Malabar, South India, with the figure of a mad saint whose actions and demeanor embodied such ambiguities. Analyzing anthropological studies of Islam probing such ambiguities in the lives of Muslims, I argue that considering the figure of the majzūb—an eccentric saint—offers key insights for understanding how normative and explorative discourses constitute contemporary religious lives. It also reveals how ambiguity is used to reconcile the tensions between the two discourses in both practice and discourse. [ABSTRACT FROM AUTHOR]

Graham's posthumous publication (Cat. Pl. Bombay, 1839) was completed by Joseph Nimmo, in addition to contributing several new species in it. Croton gibsonianus Nimmo and C. lawianus Nimmo (Euphorbiaceae) were part of this addition, and both were described based on Gibson's collection from adjoining localities in the Western India. As the diagnosis of the latter species was scant, it was subsequently interpreted in different genera viz. Dimorphocalyx, Trigonostemon and Tritaxis. Due to misinterpretation of the protologue and Gibson's Croton collection housed at K, the name C. lawianus was wrongly applied to C. gibsonianus by subsequent authors. This inadvertent application of name is corrected here and referred to the hitherto undescribed new species C. chakrabartyi. Our recent collection of C. gibsonianus has turned out to be a rediscovery after 170 years. The nomenclature, description, photographs, and distribution of C. gibsonianus are provided to avoid further taxonomic ambiguity. [ABSTRACT FROM AUTHOR]

Plant taxonomy can become complicated if handled without restraint/caution in floral documentation. Effectively, taxonomic practices provide a procedure/method for naming, reporting (publishing) and subsequent cautious filing of materials in the herbaria. A literature scrutiny provides multiple examples of lack of seriousness and dishonesty in varied areas of taxonomic research. In reporting new species, it is always desired to have an in-house deliberation for opinion, as collective wisdom/expertise helps the authors eliminate any omissions that might appear later in publications. Rediscovery reports from India frequently fail to be relevantly content-spirited. Their reporting requires great prudence and rigorous scrutiny. In this article, the long existing partial knowledge in unisexual plants in a few angiosperm families is discussed. Many a time, irrationally, status judgements (IUCN statuses) are assigned to species with inadequate information on distribution details. Nomenclature and taxonomy should go hand in hand to bring in clarity regarding any taxon and to resolve issues. Naming or struggle for a right name appears to be the priority for a near nonexistent species than for their fresh collections. Issues on naming of plants after one's own masters or relatives to oblige them are also deliberated. Concerns related to herbaria maintenance and failing in the deposition of types and vouchers in herbaria are discussed. The literature without specimen base leads to ambiguity, and spells a debacle in revisionary works and consolidation of floras. Further, there are also apprehensions linked to publishing new combinations based on publications from elsewhere and without having a grasp/judgement of the genera involved. There are also articles concerning lectotypifications undertaken by taxonomists without due enquiry. Such publications may help promote the concerned authors in their careers, but contribute little and generate greater noise in the subject. [ABSTRACT FROM AUTHOR]

The characterization of ground targets from a remotely sensed Synthetic Aperture Radar (SAR) image is addressed by polarimetric decomposition. The polarimetric SAR (PolSAR) decomposition measures the contribution of total backscatter from different scattering mechanisms using SAR images. The ambiguities present in the retrieval of scattering are the major problems associated with the model-based decomposition which could be reduced with a combination of interferometric coherence and PolSAR backscatter. The objective of this study is to improve the polarimetric decomposition model for identifying the scattering mechanisms based on the Polarimetric SAR Interferometry (PolInSAR) coherence for natural and manmade features. In this paper, we have proposed a model-based polarimetric decomposition using PolInSAR decorrelation. The PolInSAR decorrelation is exploited here to distinguish the time-varying and invariant scatterers present in the ground. The volume scattering power was calculated using the proposed decorrelation parameter which is the combination of PolInSAR coherence and decorrelation. The proposed algorithm has been tested on spaceborne multifrequency SAR datasets consisting of X-band TerraSAR-X and TerraSAR-X add-on for Digital Elevation Measurement (TanDEM-X), C-band Radarsat-2, and phased array L-band synthetic aperture radar-2 (PALSAR-2) data of advanced land observing satellite-2 (ALOS-2) PolInSAR data for the Dehradun region, India. The results show that there is a remarkable reduction in the ambiguities present in the identification of the scattering mechanism from the SAR image by using the proposed decorrelation-based decomposition model. Moreover, the algorithm is tested on X-band TerraSAR-X and TanDEM-X data of the Haridwar area and Rudrapur area, Uttarakhand, India to analyse the potential of the proposed decomposition technique in representing different manmade and natural features. [ABSTRACT FROM AUTHOR]

This paper summarizes the arguments and counterarguments within the scientific discussion on the issue of eco-consumers purchase decisions through the lens of consumer preferences and patterns of information processing in the course of eco-friendly brands purchase. The main purpose of the research is to bridge the gap in understanding why shoppers in India despite high environmental awareness and positive attitudes practice sustainable consumer behaviour by consuming less than better. Systematization of literary sources and approaches for solving the problem of the low frequency of eco-shopping indicates that positive attitudes and purchase intentions correspond with environmental concerns, however, they are not manifested in more frequent purchase actions. The relevance of the solution of this scientific problem is that it gives orientation to the firms on a better understanding of eco-market in India. Investigation of the topic reveals high ambiguity in buying decisions among young eco-buyers, who are ready to consume more but find it difficult due to high price, poor quality and distribution models of eco-firms. The research established the negligible impact of family members and friends as role models for promoting green sales. Methodological tools of the research methods were comparative studies, regression analysis, Principal Component Analysis and ANOVA to establish the effects of information processing and consumer preferences on the frequency of eco-friendly brands purchasing. The object of research is eco-consumers residing in Delhi and NCR because namely they are more educated and have better access to green products. Convenient sampling covered 194 respondents and was conducted in 2018. The paper presents the results of an empirical analysis of the effects of consumer preferences on the frequency of eco-shopping actions, which showed a significant relationship between purchase frequency and level of environmental concerns. The research empirically confirms and theoretically proves that increasing demand for information about eco-brands does not lead to more often shopping. The results of the research can be useful for eco-firms to enhance marketing-mix capable to offer competitive price, quality, distribution and communication with customers. [ABSTRACT FROM AUTHOR]

Drawing from an interview based household survey of 453 older parent(s) and adult children (sons and daughters-in-law) in the Ahmedabad district, this study utilised the solidarity-conflict-ambivalence models to understand both the perceptions and experience of joint living. Overall, findings reinforce popular imagination of the socially-sanctioned joint family as a site of reassuring continuity with high levels of congruence in reporting relational sentiments. Evidence of intergenerational stake phenomenon was observed in responses of older adults when compared with the mature child. In addition to examining normative ambivalence, I contend that joint family relations embody a concept of 'ambiguity' – an uncertain, somewhat conflictual emotive space that offers members a temporary escape without confronting the contradictions in the objective demands of expected roles. In conclusion, I assert the need to go beyond the western tools of measurement to capture a deeply complex emotive space with its regularities, irrationalities and incoherences in the experience of everyday life. [ABSTRACT FROM AUTHOR]

This article is about the tragic journeys and livelihood insecurities of coastal fisherfolk of India and Sri Lanka, who are arrested and jailed by these countries for having entered each other's arenas. These fisherfolk are victims of defined and undefined boundaries in the seas, and increasing conflicts over renewable resources. The article questions the cartographic and border anxieties of these countries, which come into fundamental contradiction with the lives, livelihoods and desires of the majority of coastal fisherfolk, who are short-term migratory subjects on an everyday basis. They are constantly subjected to categories such as insider and outsider, safety and danger, domestic and foreign, self and other. At the same time, the article reveals how these fishing communities themselves mark an ambiguous space, located as they are on the margins of the two countries, thereby providing emancipatory possibilities that can emerge from the spatial freedoms which they have practised. However, there are also some contradictory voices. Some of these fisherfolk are articulating the very same language which is used to suppress them. In attempting to highlight these complexities, the article widens our definitions of migrations, diasporas, and transnational subjects. [ABSTRACT FROM AUTHOR]

An attempt is made in this paper to report how a supervised methodology has been adopted for the task of Word Sense Disambiguation (WSD) in Bengali with necessary modifications. At the initial stage, four commonly used supervised methods, Decision Tree (DT), Support Vector Machine (SVM), Artificial Neural Network (ANN) and Naïve Bayes (NB), are developed at the baseline. These algorithms are applied individually on a data set of 13 most frequently used Bengali ambiguous words. On experimental basis, the baseline strategy is modified with two extensions: (a) inclusion of lemmatization process into the system and (b) bootstrapping of the operational process. As a result, the levels of accuracy of the baseline methods are slightly improved, which is a positive signal for the whole process of disambiguation as it opens scope for further modification of the existing method for better result. In this experiment, the data sets are prepared from the Bengali corpus, developed in the Technology Development for Indian Languages (TDIL) project of the Government of India and from the Bengali WordNet, which is developed at the Indian Statistical Institute, Kolkata. The paper reports the challenges and pitfalls of the work that have been closely observed during the experiment. [ABSTRACT FROM AUTHOR]