295 research outputs found
Scientometric portrait of Ram Gopal Rastogi
No full textPublication productivity of Indian scientist (R.G. Rastogi) has been documented.
Scientometric analysis of 312 papers by Ram Gopal Rastogi published during 1954 to 1992 in various domains: (a) Luni -solar activity and quiet -time E & F- region (57); (b) Equatorial electric field and low and mid latitude iof:osphere (78); (c) Ionospheric E- region irregularities (19); (dj Ionospheric F- region irregularities (32); and (e) Magnetic disturbance effects on the equatorial low and mid latitude ionosphere (23) were analysed. Interdomainery contents and of the number of papers: a+b were 36; b+c and b+d were 20 each; b+e were 16;. c+e were 5; a+e were 3; d+e were 2; and a+d had only one publication. Highest collaborations were with H. Chandra (61), M.R. Deshpande (42), and G. Sethia (19) out of his total 97 collaborators. His highest productivity was during 1978 with 28 papers followed by 19 papers during 1977. The core journals preferred by him for publishing papers were: Indian Journal of Radio & Space Physics, India, and Journal of Atomic & Terrestrial Physics, UK (59 each), followed by Proceedings of the Indian Academy of Sciences, India (34). Most prolific title keywords with their frequencies were: Ionosphere (92); Equatorial (61); F-region (53); Equatorial electrojet region (40), and Magnetic equator (30)
ICAS:MP Lecture by Niraja Gopal Jayal (Jawaharlal Nehru University)
No full textChair: Kalpana Kannabiran (Council for Social Development, Hyderabad) 23 September 2019 Venue: CSDS, Seminar Room, 6 pm – 8 pm Niraja Gopal Jayal is Professor at the Centre for the Study of Law and Governance at the Jawaharlal Nehru University, New Delhi. Her book Citizenship and its Discontents (Harvard University Press, 2013) won the Ananda Kentish Coomaraswamy Prize for 2015. She is also the author of Representing India: Ethnic Diversity and the Governance of Public Institutions (Palgrave ..
ASIP data-plane processor for multi-standard wireless protocol processing
No full textEvolving Multi-Protocol Multi-Band Software Defined Radio (SDR) devices aim at supporting multiple protocols seamlessly and efficiently. The design of such radios necessitates flexibility in physical layer processing, flexibility in routing packets through processing engines and flexibility in radio frequency reception/transmission. This dissertation addresses an efficient implementation of flexible physical layer processing (PHY) for Interleaving, De-Interleaving and linear Minimum Mean Square Error (MMSE) detection in Multiple Input Multiple Output (MIMO) receivers through Application Specific Instruction Set Processors (ASIPs). The thesis defines and develops a WINLAB cognitive radio (WiNC2R) compatible data-plane ASIP architecture along with suitable hardware-software partitioning of the Processing Engine unit. Given the requirement of very significant design time and the lack of the flexibility after design, dedicated ASIC for PHY may not be a viable option although it has the best performance among all available options. The software application running on general purpose processor cannot satisfy the throughput requirements of the wireless standards. ASIPs provide a better trade-off between flexibility and performance, with the advantage of considerably lower design time than ASICs. We design an efficient multi-standard (802.11a, 802.16e/m) supporting Interleaver/De-Interleaver ASIP, satisfying the throughput requirements for all the modulation-schemes/data-rates in both of the standards. It can be programmed to scale for supporting future wireless standards (that use Block Interleaving/De-Interleaving). We also study viability of a flexible MIMO MMSE detector ASIP supporting variable MR (Number of receiving antennas) * MT (Number of transmitting antennas) operations. We have analyzed the implementation of an hardware-centric algorithm for MIMO detection on an ASIP and also improved its performance with the help of techniques such as fixed point implementation, Single Instruction Multiple Data (SIMD) and Very Long Instruction Word (VLIW). Analysis of the design performance results for MIMO ASIP indicates the limitations of hardware-implementation-specific algorithms on ASIP. We also provide the account of design decisions such as custom ports, memory interfaces and registers that are added to the data-plane processor ASIPs in order to substitute them for dedicated hardware engines in the WiNC2R platform.M.S.Includes bibliographical referencesby Mohit Gopal Wan
Scientometric analysis of synchronous references in the Physics Nobel lectures, 1981-1985 : a pilot study
No full textScientometric analysis of synchronous references in the nine Physics Nobel lectures by Nicolaas Bloembergen (1981), Arthur L. Schawlow (1981), Kai M. Siegbahn (1981), Kenneth G. Wilson (1982), Subrahmanyan Chandrasekhar (1983), William A. Fowler (1983), Carlo Rubbia (1984), Simon van der Meer (1984), and Klaus von Klitzing (1985) indicated high variations: No. of Synchronous References ranged from 24 (Meer) to 283 (Siegbahn); Synchronous Self-References ranged from 5 (Rubbia) to 88 (Siegbahn); synchronous references to others ranged from 10 (Chandrasekhar) to 255 (Wilson); Synchronous Self-Reference Rates ranged from 6.66 % (Rubbia) to 65.51 % (Chandrasekhar); Single-Authored References ranged from 15 (Klitzing) to 160 (Wilson); Multi-Authored References ranged from 4 (Chandrasekhar) to 194 (Siegbahn); Collaboration Coefficient in the synchronous references ranged from 0.14 (Chandrasekhar) to 0.75 (Klitzing); and Recency (age of 50 % of the latest references) ranged from 2 (Klitzing) to 18 (Chandrasekhar) years. Seventy five per cent of the references belonged to journal articles. Highly referred journals were Astrophysical Journal, Physical Review B, Physical Review Letters, Arkiv Fuer Fysik, Surface Science, Physics Letters, and IEEE Transactions on Nuclear Science.
See: Scientometrics Vol. 61 No.1, pp.55-68
Remark on <i>p</I>-<i>d< Operator
No full textGopal, Dhananjay/0000-0001-8217-2778In this short communication, we show that P-D, operator fall in the class of weakly compatible (respectively, occasionally weakly compatible) in the presence of a unique common fixed point (respectively, multiple common fixed points) of the given maps.CSIR, Govt. of India [25(0215)/13/EMR-II]The first author thanks for the support of CSIR, Govt. of India, Grant No.25(0215)/13/EMR-II.Emerging Sources Citation Inde
Socioeconomic impact of TB on patients registered within RNTCP and their families in the year 2007 in Chennai, India
No full textBackground: Tuberculosis patients are registered in government clinics under Directly Observed Treatment Short-course (DOTS) program in Chennai city catering to 4.34 million population. With the entire country geographically covered under the DOTS program, research into socioeconomic impact of TB on patients and their households is crucial for providing comprehensive patient-friendly TB services and to document the benefits of DOTS. Objective: To assess the social and economic impact of TB on patients registered under DOTS program and their families. Materials and Methods: A cross-sectional study of 300 TB patients was done using a pre-coded semi-quantitative questionnaire between March and June 2007 in all the Tuberculosis Units (TUs) of Chennai city. Results: Social and economic impact was perceived by 69.0% and 30.3% patients, respectively. About 24.3% suffered from both social and economic impact, while 75% patients suffered from any one form of impact. Social impact was perceived by more female patients as compared to males (80.7% vs. 62%; P < 0.001). More patients with extra-pulmonary disease (44.4%) and patients belonging to joint families (40.7%) perceived economic impact (P < 0.05). Conclusion: After 8 years of DOTS implementation, the present study has shown that with the availability of DOTS, percentage of patients who mortgaged assets or took loans has reduced. Social impact of TB is still perceived by two-thirds of the patients (69%). Elimination or reduction of social stressors with specific, focused, and intense social support services, awareness generation, and counseling to patients and families need to be built into the program
From Acoustics to Articulation : Study of the acoustic-articulatory relationship along with methods to normalize and adapt to variations in production across different speakers
No full textThe focus of this thesis is the relationship between the articulation ofspeech and the acoustics of produced speech. There are several problems thatare encountered in understanding this relationship, given the non-linearity,variance and non-uniqueness in the mapping, as well as the differences thatexist in the size and shape of the articulators, and consequently the acoustics,for different speakers. The thesis covers mainly four topics pertaining to thearticulation and acoustics of speech.The first part of the thesis deals with variations among different speakersin the articulation of phonemes. While the speakers differ physically in theshape of their articulators and vocal tracts, the study tries to extract articula-tion strategies that are common to different speakers. Using multi-way linearanalysis methods, the study extracts articulatory parameters which can beused to estimate unknown articulations of phonemes made by one speaker;knowing other articulations made by the same speaker and those unknown ar-ticulations made by other speakers of the language. At the same time, a novelmethod to select the number of articulatory model parameters, as well as thearticulations that are representative of a speaker’s articulatory repertoire, issuggested.The second part is devoted to the study of uncertainty in the acoustic-to-articulatory mapping, specifically non-uniqueness in the mapping. Severalstudies in the past have shown that human beings are capable of producing agiven phoneme using non-unique articulatory configurations, when the artic-ulators are constrained. This was also demonstrated by synthesizing soundsusing theoretical articulatory models. The studies in this part of the the-sis investigate the existence of non-uniqueness in unconstrained read speech.This is carried out using a database of acoustic signals recorded synchronouslyalong with the positions of electromagnetic coils placed on selected points onthe lips, jaws, tongue and velum. This part, thus, largely devotes itself todescribing techniques that can be used to study non-uniqueness in the sta-tistical sense, using such a database. The results indicate that the acousticvectors corresponding to some frames in all the phonemes in the databasecan be mapped onto non-unique articulatory distributions. The predictabil-ity of these non-unique frames is investigated, along with verifying whetherapplying continuity constraints can resolve this non-uniqueness.The third part proposes several novel methods of looking at acoustic-articulatory relationships in the context of acoustic-to-articulatory inversion.The proposed methods include explicit modeling of non-uniqueness usingcross-modal Gaussian mixture modeling, as well as modeling the mappingas local regressions. Another innovative approach towards the mapping prob-lem has also been described in the form of relating articulatory and acousticgestures. Definitions and methods to obtain such gestures are presented alongwith an analysis of the gestures for different phoneme types. The relationshipbetween the acoustic and articulatory gestures is also outlined. A method toconduct acoustic-to-articulatory inverse mapping is also suggested, along withva method to evaluate it. An application of acoustic-to-articulatory inversionto improve speech recognition is also described in this part of the thesis.The final part of the thesis deals with problems related to modeling infantsacquiring the ability to speak; the model utilizing an articulatory synthesizeradapted to infant vocal tract sizes. The main problem addressed is related tomodeling how infants acquire acoustic correlates that are normalized betweeninfants and adults. A second problem of how infants decipher the number ofdegrees of articulatory freedom is also partially addressed. The main contri-bution is a realistic model which shows how an infant can learn the mappingbetween the acoustics produced during the babbling phase and the acous-tics heard from the adults. The knowledge required to map correspondingadult-infant speech sounds is shown to be learnt without the total numberof categories or one-one correspondences being specified explicitly. Instead,the model learns these features indirectly based on an overall approval rating,provided by a simulation of adult perception, on the basis of the imitation ofadult utterances by the infant model.Thus, the thesis tries to cover different aspects of the relationship betweenarticulation and acoustics of speech in the context of variations for differentspeakers and ages. Although not providing complete solutions, the thesis pro-poses novel directions for approaching the problem, with pointers to solutionsin some contexts.QC 20111222Computer-Animated language Teachers (CALATea), Audio-Visual Speech Inversion (ASPI
Imitating Adult Speech: An Infant's Motivation
No full textThis paper tries to detail two aspects of speech acquisition by infants which are often assumed to be intrinsic or innate knowledge, namely number of degrees of freedom in the articulatory parameters and the acoustic correlates that find the correspondence between adult speech and the speech produced by the infant. The paper shows that being able to distinguish the different vowels in the vowel space of the certain language is a strong motivation for choosing both a certain number of independent articulatory parameters as well as a certain scheme of acoustic normalization between adult and child speech.</p
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Systems biology of breast cancer
No full textBreast cancer, with an alarming incidence rate throughout the globe, has attracted significant investigations to identify disease specific biomarkers. Among these, oestrogen receptor (ER) occupies a central role where overexpression is a prognostic indication for breast cancer. The cross-talk between the responsible contenders of ER-associated genes potentially play an important role in the disease aetiology. Investigation of such cross talk is the focus of this thesis. The development of high throughput technologies such as expression microarrays has paved the way for investigating thousands of genes at a time. Microarrays with their high data volume, multivariate nature and non-linearity pose challenges for analysing using conventional statistical approaches. To combat these challenges, computational researchers have developed machine learning approaches such as Artificial Neural Networks (ANNs). This thesis evaluates ANNs based methodologies and their application to the analysis of microarray data generated for breast cancer cases of differing oestrogen receptor status. Furthermore they are used for network inferencing to identify interactions between ER-associated markers and for the subsequent identification of putative pathway elements. The present thesis shows that it is possible to identify some ER-associated breast cancer relevant markers using ANNs. These have been subsequently validated on clinical breast tumour samples highlighting the promise of this approach
Important regions in the articulator trajectory
No full textThis paper deals with identifying important regions in the articulatory trajectory based on the physical properties of the trajectory. A method to locate critical time instants as well as the key articulator positions is suggested. Acoustic-to-Articulatory Inversion using linear and non-linear regression isperformed using only these critical points. The accuracy of inversion is found to be almost the same as using all the data points.</p
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