61 research outputs found

    Numerical modeling for long term performance of soil-bentonite cut-off walls in unsaturated soil zone

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    ABSTRACT The construction practices of containment walls are extremely important in this competitive economic market, but development is limited. Unsaturated zone is an integral part of the geotechnical problems, as it affects on any kind of soils structures. The unsaturated zone plays significant role in many aspects of water flow and contaminant transport, including containment system such as: cut-off walls, infiltration, soil moisture storage, evaporation, plant water uptake, ground water recharge, erosion, and runoff. This research focuses on the hydraulic sustainability and performance of soil-bentonite cutoff walls (Britton et al, 2004) models showing hydraulic behavior of barrier walls. The cutoff wall are designed and constructed to stop contaminated flow which causes contamination nearby useful fields permit excavation dewatering, and reduce seepage beneath and through dams. Evans et al. (1995) proposed that there is a lack of information about the in situ performance of vertical soil-bentonite cutoff wall technology. The effectiveness of these cutoff walls depends on the hydraulic conductivity of the soil-bentonite slurry, ksb. There are several methods available to measure the hydraulic conductivity of soil-bentonite, but there is uncertainty of getting true representative data for hydraulic conductivity that is happening in in-situ cut-off wall. Among the various analytical and numerical models to predict water and or solute transfer process, Richard’s equation and Fickian-based convection-dispersion equation for solute transport are most popular models. Hydraulic conductivity through cut-off wall is modeled in this research with idealized initial boundary conditions and feed them to HYRUS software to obtain different results, such as: soil water characteristics, suction profile with depth, volumetric water contents etc. Here this is an effort to do something one of the cheapest cut-off walls that can be designed instead of constructing heavy construction. The cut-off can be constructed with soil-bentonite slurry which can resist contaminant transport from particular place for a time of interests. There are some researchers (Brooks and Corey, 1964, van Genuchten, 1980, Vogel and Cislerova, 1988, Kosugi, 1995, Durner, 1994) who came up with good models on hydraulic properties of soil and HYDRUS is based on those models

    Addressing issues in defining the Love number for black holes

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    We present an analytic method for calculating the tidal response function of a non-rotating and a slowly rotating black hole from the Teukolsky equation in the small frequency and the near horizon limit. We point out that in the relativistic context, there can be two possible definitions of the tidal Love number and the dissipative part that arise from the tidal response function. Our results suggest that both of these definitions predict zero tidal Love number for a non-rotating black hole. On the other hand, for a slowly rotating black hole in a generic tidal environment, these two definitions of the tidal Love number do not coincide. While one procedure suggests a zero tidal Love number, the other procedure gives a purely imaginary tidal Love number. As expected, the dissipative terms differ as well. We emphasize that in our analysis we keep all the terms linear in the frequency, unlike previous works in the literature. Following this, we propose a procedure to calculate the tidal response function and hence the Love number for an arbitrarily rotating black hole.Comment: 24 pages, 1 figur

    Comparative study of some routinely measured Serum biochemical parameters between acute exacerbation of Chronic Obstructive Pulmonary Disease and stable Chronic Obstructive Pulmonary Disease patients in a tertiary care hospital of Kolkata: an attempt to make simple prognostic indicators

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    Background: Patients with COPD often have exacerbations which frequently require hospitalization, resulting in higher mortality rates and costs than patients managed at OPD. Some easily available blood parameters in both stable COPD and AECOPD patients are measured that can be done in every patient even in poor resource settings. Finally, Results were analysed statistically to find out if there is any presence of significant difference of biochemical profile in stable COPD patients and AECOPD patients with or without any prognostic significance.Methods: In institution based observational case control study, authors measured 1.  FBS and PPBS 2. Serum Urea and Creatinine 3. Serum Electrolytes- Na+, K+, Cl- 4. LFT  5. Uric acid in both stable COPD(n=50) and AECOPD (n=50) patients. Finally, Results were analysed statistically to find out if there is any presence of significant difference of biochemical profile in stable COPD patients and AECOPD patients.Results: AECOPD patients had statistically significant higher urea, uric acid levels and higher fasting hyperglycemia than stable COPD patients. Hypernatremia, hyponatremia and hyperkalemia, hypokalemia - all were significantly higher in AECOPD group. Low level of serum bilirubin and higher level of AST and ALP were common in AECOPD patients. AECOPD patients with high urea value (>50 mg/dl) (but not high creatinine) was associated with poor patient outcome in respect to ICU transfer, death and prolonged hospital stay. Low bilirubin, high ALP and AST level in AECOPD patients was associated with higher ICU transfer and mortality but only high ALP level was associated with prolonged hospital stay. High uric acid level (>6 mg/dl) was a major determinant of ICU transfer, mortality and prolonged hospital stay.Conclusions: Predicting exacerbation by these parameters early in the course of disease can decrease morbidity and mortality as well as health care cost to great extent. By measuring the changes in it can also be predicted early who will need ICU support in future and who can be treated at ward

    A Comprehensive Review on Audio based Musical Instrument Recognition: Human-Machine Interaction towards Industry 4.0

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    Over the last two decades, the application of machine technology has shifted from industrial to residential use. Further, advances in hardware and software sectors have led machine technology to its utmost application, the human-machine interaction, a multimodal communication. Multimodal communication refers to the integration of various modalities of information like speech, image, music, gesture, and facial expressions. Music is the non-verbal type of communication that humans often use to express their minds. Thus, Music Information Retrieval (MIR) has become a booming field of research and has gained a lot of interest from the academic community, music industry, and vast multimedia users. The problem in MIR is accessing and retrieving a specific type of music as demanded from the extensive music data. The most inherent problem in MIR is music classification. The essential MIR tasks are artist identification, genre classification, mood classification, music annotation, and instrument recognition. Among these, instrument recognition is a vital sub-task in MIR for various reasons, including retrieval of music information, sound source separation, and automatic music transcription. In recent past years, many researchers have reported different machine learning techniques for musical instrument recognition and proved some of them to be good ones. This article provides a systematic, comprehensive review of the advanced machine learning techniques used for musical instrument recognition. We have stressed on different audio feature descriptors of common choices of classifier learning used for musical instrument recognition. This review article emphasizes on the recent developments in music classification techniques and discusses a few associated future research problems

    "The fruits of independence": Satyajit Ray, Indian nationhood and the spectre of empire

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    Challenging the longstanding consensus that Satyajit Ray's work is largely free of ideological concerns and notable only for its humanistic richness, this article shows with reference to representations of British colonialism and Indian nationhood that Ray's films and stories are marked deeply and consistently by a distinctively Bengali variety of liberalism. Drawn from an ongoing biographical project, it commences with an overview of the nationalist milieu in which Ray grew up and emphasizes the preoccupation with colonialism and nationalism that marked his earliest unfilmed scripts. It then shows with case studies of Kanchanjangha (1962), Charulata (1964), First Class Kamra (First-Class Compartment, 1981), Pratidwandi (The Adversary, 1970), Shatranj ke Khilari (The Chess Players, 1977), Agantuk (The Stranger, 1991) and Robertsoner Ruby (Robertson's Ruby, 1992) how Ray's mature work continued to combine a strongly anti-colonial viewpoint with a shifting perspective on Indian nationhood and an unequivocal commitment to cultural cosmopolitanism. Analysing how Ray articulated his ideological positions through the quintessentially liberal device of complexly staged debates that were apparently free, but in fact closed by the scenarist/director on ideologically specific notes, this article concludes that Ray's reputation as an all-forgiving, ‘everybody-has-his-reasons’ humanist is based on simplistic or even tendentious readings of his work

    Improved upper limits on the stochastic gravitational-wave background from 2009-2010 LIGO and Virgo data

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    Paper producido por "The LIGO Scientific Collaboration and the Virgo Collaboration". (En el registro se mencionan solo algunos autores de las decenas de personas que participan).Gravitational waves from a variety of sources are predicted to superpose to create a stochastic background. This background is expected to contain unique information from throughout the history of the Universe that is unavailable through standard electromagnetic observations, making its study of fundamental importance to understanding the evolution of the Universe. We carry out a search for the stochastic background with the latest data from the LIGO and Virgo detectors. Consistent with predictions from most stochastic gravitational-wave background models, the data display no evidence of a stochastic gravitational-wave signal. Assuming a gravitational-wave spectrum of ΩGWðfÞ ¼ Ωαðf=frefÞα, we place 95% confidence level upper limits on the energy density of the background in each of four frequency bands spanning 41.5–1726 Hz. In the frequency band of 41.5–169.25 Hz for a spectral index of α¼ 0, we constrain the energy density of the stochastic background to be ΩGWðfÞ <5.6 × 10−6. For the 600–1000 Hz band, ΩGWðfÞ <0.14ðf=900 HzÞ3, a factor of 2.5 lower than the best previously reported upper limits. We find ΩGWðfÞ <1.8 × 10−4 using a spectral index of zero for 170–600 Hz and ΩGWðfÞ < 1.0ðf=1300 HzÞ3 for 1000–1726 Hz, bands in which no previous direct limits have been placed. The limits in these four bands are the lowest direct measurements to date on the stochastic background. We discuss the implications of these results in light of the recent claim by the BICEP2 experiment of the possible evidence for inflationary gravitational waves.http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.113.231101publishedVersionFil: Aasi, J. LIGO. California Institute of Technology; Estados Unidos de América.Fil: Maglione, C. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Maglione, C. Argentinian Gravitational Wave Group; Argentina.Fil: Quiroga, G. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina.Fil: Quiroga, G. Argentinian Gravitational Wave Group; Argentina.Física de Partículas y Campo
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