423 research outputs found
Performance of paddy-cum-prawn culture in rainfed low land ecosystem of Sunderbans
Performance of both paddy (Var. NC 492) and prawn Penaeus monodon were assessed for two years during wet-season in rainfed lowland ecosystem with a view to study the economic viability of paddy-cum-prawn culture in the coastal saline zone of West Bengal. Both mono and dual culture of paddy and prawn were tried in the study. Fingerlings of prawn (α 35,000 haˉ¹) of 10-15 mm size were reared for about three and half months with and without fish feed. It was observed that addition of fish feed resulted in higher (57.7%) production of prawn (2.65 mg/haˉ¹) but not rice. Such increase in prawn production was 1.6 times higher when no feed was provided and 1.4 times higher when grown as sole crop. However, paddy, whether grown as mono or mixed culture, did not differ in yield significantly. In dual culture, the benefit - cost ratio was higher (6.83) when prawn was grown with feed and it was maximum (36.0) when grown without feed as sole crop. The study, therefore, indicates that paddy-cum-prawn culture under low land ecosystem of the coastal saline zone is enterprising particularly for small and marginal farmers who fear to take risk of growing prawn alone at the cost of paddy
Effect of repeated blast Vibrations on damage intensity of granitic rock mass at an hydroelectric Construction project
Rock blasting induced ground vibrations produce deformations in the vicinity of blasting site. The effect of blast loading on structures is a growing concern of safety and stability. Extensive data are available on the behavior of surface structures subjected to blast vibrations. However, only limited information is available on the effect of blast induced dynamic forces on the underground opening like tunnels and caverns. The reported findings state that blast induced dynamic stress, one or several cycle of repeated strains may cause deterioration in the rock mass or create damage to the dam foundation. This paper deals with the research work carried out at jurala hydroelectric power project (JHPP) on the effect of repeated blast vibrations on powerhouse foundation in a jointed rock mass. The damage caused by blast induced vibrations can be categorized in to two types: (i) near-field damage due to high frequency vibrations when blast is occurring in the close proximity and (ii) far-field damage due to low frequency vibrations when the blast is occurring relatively farther distance. The near-field damage was assessed by monitoring ballast vibrations and borehole camera inspection survey. The far field damage was assessed by continuous monitoring of vibrations, borehole camera inspection survey and P-wave velocity measurement by ultrasonic testing machine. Borehole camera was used to examine the crack extension and damage inspection of rock mass. This paper reveals that repeated dynamic loading imparted on the jointed rock mass from subsequent blast, in the vicinity, resulted in damage even at 22% of critical peak particle velocity (Vmax). The far-field damage due to the repeated blast loading of 40-45 rounds was more than 77% of he near-field damage. The results of the experimental study indicated that vibration levels, even at less than critical Vmax, can cause safety and stability problems to the structures in /on joined rock mass, when exposed to the repeated blast loading. This paper stresses the need for consideration of the effect of repeated blast loading in fixing the threshold limits of Vmax to avoid far-field damage
Fragalyst 3.0: An indigenous fragmentation assessment tool based on digital image analysis – application and analysis
Fragalyst 3.0 is an advanced version of the Fragalyst 2.0 developed indigenously by CIMFR and Wavelet Group Pune. The software has multiple functions where the digital images of blasted fragments can be analysed for size distributions (BBSD) and the in situ block size distribution (IBSD)can also be determined using the joint frequencies in a blast face. The software then uses the Bond;s index to determine the explosive energy utilisation in a blast. initially an image of the face is to be imported and joints determined by using a scanline method which in turn determines the IBSD. Once blast is carried out on the same face sufficient number of images (at least 15) need to be imported in the software and analysed for fragmentation distribution. Several options of image enhancement, resize and crop are also available along with a large combination of threshold parameters which makes edge detection easy. The detected edges of fragments can be edited using advanced tools. The analysis of all the individual images is then called for a merged analysis of the blasted fragment size distribution (BBSD). A fines correction option is now available for correcting the BBSD for fines. The area between the BBSD and IBSD curves determines the explosive energy utilised in the blast. The software results have been compared to the results obtained with imported software and results are conforming. The software has been tested at number of sites in India and significant changes in productivity have been reported. There are some advanced features included in the software such as shape factor, spherocity and other distributions of blasted fragments, distance measurements and angle calculations which can be useful to an inquisitive researcher. The paper details the capabilities of Fragalyst 3.0 along with few applications and respective analysis
Analysis of the effects of spaceflight and local administration of thrombopoietin to a femoral defect injury on distal skeletal sites
With increased human presence in space, bone loss and fractures will occur. Thrombopoietin (TPO) is a recently patented bone healing agent. Here, we investigated the systemic effects of TPO on mice subjected to spaceflight and sustaining a bone fracture. Forty, 9-week-old, male, C57BL/6 J were divided into 4 groups: (1) Saline+Earth; (2) TPO + Earth; (3) Saline+Flight; and (4) TPO + Flight (n = 10/group). Saline- and TPO-treated mice underwent a femoral defect surgery, and 20 mice were housed in space ("Flight") and 20 mice on Earth for approximately 4 weeks. With the exception of the calvarium and incisor, positive changes were observed in TPO-treated, spaceflight bones, suggesting TPO may improve osteogenesis in the absence of mechanical loading. Thus, TPO, may serve as a new bone healing agent, and may also improve some skeletal properties of astronauts, which might be extrapolated for patients on Earth with restraint mobilization and/or are incapable of bearing weight on their bones
A reconstruction theorem for almost-commutative spectral triples
We propose an expansion of the definition of almost-commutative spectral
triple that accommodates non-trivial fibrations and is stable under inner
fluctuation of the metric, and then prove a reconstruction theorem for
almost-commutative spectral triples under this definition as a simple
consequence of Connes's reconstruction theorem for commutative spectral
triples. Along the way, we weaken the orientability hypothesis in the
reconstruction theorem for commutative spectral triples, and following
Chakraborty and Mathai, prove a number of results concerning the stability of
properties of spectral triples under suitable perturbation of the Dirac
operator.Comment: AMS-LaTeX, 19 pp. V4: Updated version incorporating the erratum of
June 2012, correcting the weak orientability axiom in the definition of
commutative spectral triple, stengthening Lemma A.10 to cover the
odd-dimensional case and the proof of Corollary 2.19 to accommodate the
corrected weak orientability axio
The Effects of Tachyonic and Phantom Fields in the Intermediate and Logamediate Scenarios of the Anisotropic Universe
In this work, we have analyzed two scenarios namely, "intermediate" and
"logamadiate" scenarios for closed, open and flat anisotropic universe in
presence of phantom field, normal tachyonic field and phantom tachyonic field.
We have assumed that there is no interaction between the above mentioned dark
energy and dark matter. In these two types of the scenarios of the universe,
the nature of the scalar fields and corresponding potentials have been
investigated. In intermediate scenario, (i) the potential for normal tachyonic
field decreases, (ii) the potentials for phantom tachyonic field and phantom
field increase with the corresponding fields. Also in logamediate scenario, (i)
the potential for normal tachyonic field increases, (ii) the potentials for
phantom tachyonic field and phantom field decrease with the corresponding
fields.Comment: 20 figure
Fractional Action Cosmology: Emergent, Logamediate, Intermediate, Power law Scenarios of the Universe and Generalized Second Law of Thermodynamics
In the framework of Fractional Action Cosmology (FAC), we study the
generalized second law of thermodynamics for the Friedmann Universe enclosed by
a boundary. We use the four well-known cosmic horizons as boundaries namely,
apparent horizon, future event horizon, Hubble horizon and particle horizon. We
construct the generalized second law (GSL) using and without using the first
law of thermodynamics. To check the validity of GSL, we express the law in the
form of four different scale factors namely emergent, logamediate, intermediate
and power law. For Hubble, apparent and particle horizons, the GSL holds for
emergent and logamediate expansions of the universe when we apply with and
without using first law. For intermediate scenario, the GSL is valid for
Hubble, apparent, particle horizons when we apply with and without first law.
Also for intermediate scenario, the GSL is valid for event horizon when we
apply first law but it breaks down without using first law. But for power law
expansion, the GSL may be valid for some cases and breaks down otherwise.Comment: 24 pages, 32 figures, Accepted in Int. J. Theor. Phy
Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector
A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results
Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC
Measurements of inclusive jet suppression in heavy ion collisions at the LHC
provide direct sensitivity to the physics of jet quenching. In a sample of
lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated
luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with
a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the
transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the
anti-kt algorithm with values for the distance parameter that determines the
nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of
the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp.
Jet production is found to be suppressed by approximately a factor of two in
the 10% most central collisions relative to peripheral collisions. Rcp varies
smoothly with centrality as characterized by the number of participating
nucleons. The observed suppression is only weakly dependent on jet radius and
transverse momentum. These results provide the first direct measurement of
inclusive jet suppression in heavy ion collisions and complement previous
measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables,
submitted to Physics Letters B. All figures including auxiliary figures are
available at
http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02
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