139 research outputs found
Multi-objective optimization of an industrial styrene reactor using Harmony Search Algorithm
Multi-objective optimization of industrial styrene reactor is done using Harmony Search algorithm. Harmony search algorithm is a recently developed meta-heuristic algorithm which is inspired by musical improvisation process aimed towards obtaining the best harmony. Three objective functions – productivity, selectivity and yield are optimized to get best combination of decision variables for styrene reactor. All possible cases of single and multi-objective optimization have been considered. Pareto optimal sets are obtained as a result of the optimization study. Results reveal that optimized solution using harmony search algorithm gives better operating conditions than industrial practice
On the spectrum of colour sextet scalars in realistic SO(10) GUT
Incorporation of the standard model Yukawa interactions in a grand unified
theory (GUT) often predicts varieties of new scalars that couple to the
fermions and lead to some novel observational effects. We assess such a
possibility for the colour sextet diquark scalars within the realistic
renormalizable models based on GUT. The spectrum consists of five
sextets: , ,
, and .
Computing explicitly their couplings with the quarks, we evaluate their
contributions to the neutral meson-antimeson mixing and baryon number-violating
processes like neutron-antineutron oscillation. The latter arises because of a
violating trilinear coupling between the sextets which also contributes
to some of the quartic couplings and perturbativity of the same leads to strong
limits on the sextet masses. Using the values of the breaking scale and
Yukawa couplings permitted in the realistic models, we derive constraints on
the masses of these scalars. It is found that along with any of the
remaining sextets cannot be lighter than the breaking scale,
simultaneously. In the realm of realistic models, this implies no observable
- oscillation in near future experiments. We also point out a
possibility in which sub-GUT scale and a pair of , allowed by the
other constraints, can viably produce the observed baryon asymmetry of the
universe.Comment: 25 Pages, 7 Captioned Figures, 1 Tabl
Anatomy of scalar mediated proton decays in models
Realistic models based on the renormalizable grand unified theories have
varieties of scalars, many of which are capable of mediating baryon () and
lepton () number non-conserving processes. We identify all such scalar
fields residing in , and dimensional
irreps of which can induce baryon and lepton number violating
interactions through the leading order and operators. Explicitly
computing their couplings with the standard model fermions, we derive the
effective operators including the possibility of mixing between the scalars
stemming from a given representation. We find that such interactions at
are mediated by only three sets of scalars: , and and their conjugates. In the models with
and , only the first has appropriate couplings
to mediate the proton decay. While and can induce
baryon number violating interactions when is present,
does not contribute to the proton decay at tree level because of its flavour
antisymmetric coupling. Three additional colour triplets and their conjugates
can mediate nucleon decay via operators which violate also the . We
give general expressions for partial widths of proton in terms of the
fundamental Yukawa couplings and use these results to explicitly compute the
proton lifetime and branching ratios for the minimal non-supersymmetric
model based on and Higgs. We find that
the proton preferably decays into or and
list several distinct features of scalar mediated proton decay. If the latter
dominates over the gauge mediated contributions, the proton decay spectrum
provides a direct probe to the flavour structure of the underlying grand
unified theory.Comment: 34 pages, 4 tables, 3 captioned figures. Version published in JHE
A randomized, controlled study to compare the effects of intravenous labetalol and esmolol on haemodynamic changes during laryngoscopy and intubation
Background: Direct laryngoscopy and endotracheal intubation frequently induce cardiovascular stress response characterised by hypertension and tachycardia due to reflex sympathetic stimulation. Considering the clinical significance of these changes stress attenuation is needed to blunt these responses. β- blockers are used to reduce the unwanted hemodynamic responses. Esmolol is ultra-short acting cardio selective β blocker. Labetalol is useful in not only attenuating the response to laryngoscopy and intubation but also in preventing perioperative cardiovascular events. Present study compared the efficacy of esmolol and labetalol for attenuation of sympathomimetic response to laryngoscopy and intubation.Methods: It was a prospective, randomized, controlled study carried out in 75 adult patients with ASA 1 and ASA 2 posted for elective surgeries. Patients were allocated randomly into Group-1 (esmolol) and Group-2 (labetalol) and Group-3 (placebo) of 25 patients each. Inj. esmolol (1mg/kg) or Inj. labetalol (0.4 mg/kg) or placebo (0.9NS) dissolved up to 5 ml in distilled water was injected intravenously 5 minutes prior to intubation. All patients premeditated with Inj. glycopyrrolate (4µg/kg). Patient were then induced with Inj. propofol (2mg/kg), Inj. scoline (2mg/kg) given followed by laryngoscopy and intubation. Haemodynamic readings were noted at T0 (baseline before injecting the drug), T1 (1 minute after injecting the drug), T2 (after intubation), T3 (2 minutes after intubation), T4 (4 minutes after intubation), T5 (6 minutes after intubation), T6 (8 minutes after injection), T7 (10 minutes after injection).Results: Gr-1, Gr-2 and Gr-3, when compared with each other for systolic BP, diastolic BP, mean BP, and HR, showed a statistically significant difference at different intervals.Conclusions: Both the drugs are found to be effective in attenuation of hemodynamic reflex without any side effects. Further studies are recommended to substantiate the findings in present study
Search for Lorentz-violation through sidereal effect at NO{\nu}A Experiment
Long-baseline neutrino oscillation experiments offer a unique laboratory to
test the fundamental Lorentz symmetry, which is heart of both the standard
model of particle and general relativity theory. Deviations from the standard
neutrino oscillation or the sidereal modulation in neutrino events will
smoking-gun experimental signature of Lorentz and CPT violation. In this study,
we investigate the impact of the sidereal effect on standard neutrino
oscillation measurements within the context of the NO{\nu}A experiment.
Additionally, we assess the sensitivity of the NO{\nu}A experiment to detect
Lorentz-violating interactions, taking into account the sidereal effect.
Furthermore, we highlight potential of the NO{\nu}A experiment to set the new
constraints on anisotropic Lorentz-violating parameters
EPASAD: Ellipsoid decision boundary based Process-Aware Stealthy Attack Detector
Due to the importance of Critical Infrastructure (CI) in a nation's economy,
they have been lucrative targets for cyber attackers. These critical
infrastructures are usually Cyber-Physical Systems (CPS) such as power grids,
water, and sewage treatment facilities, oil and gas pipelines, etc. In recent
times, these systems have suffered from cyber attacks numerous times.
Researchers have been developing cyber security solutions for CIs to avoid
lasting damages. According to standard frameworks, cyber security based on
identification, protection, detection, response, and recovery are at the core
of these research. Detection of an ongoing attack that escapes standard
protection such as firewall, anti-virus, and host/network intrusion detection
has gained importance as such attacks eventually affect the physical dynamics
of the system. Therefore, anomaly detection in physical dynamics proves an
effective means to implement defense-in-depth. PASAD is one example of anomaly
detection in the sensor/actuator data, representing such systems' physical
dynamics. We present EPASAD, which improves the detection technique used in
PASAD to detect these micro-stealthy attacks, as our experiments show that
PASAD's spherical boundary-based detection fails to detect. Our method EPASAD
overcomes this by using Ellipsoid boundaries, thereby tightening the boundaries
in various dimensions, whereas a spherical boundary treats all dimensions
equally. We validate EPASAD using the dataset produced by the TE-process
simulator and the C-town datasets. The results show that EPASAD improves
PASAD's average recall by 5.8% and 9.5% for the two datasets, respectively.Comment: Submitte
Performance of NavIC for studying the ionosphere at an EIA region in India
This paper emphasizes on NavIC's performance in ionospheric studies over the
Indian subcontinent region. The study is performed using data of one year
(2017-18) at IIT Indore, a location near the northern crest of Equatorial
Ionization Anomaly (EIA). It has been observed that even without the individual
error corrections, the results are within of NavIC VTEC estimates
observed over the 1\ensuremath{^{\circ}} x 1\ensuremath{^{\circ}} grid of IPP
surrounding the GPS VTEC estimates for most of the time. Additionally,
ionospheric response during two distinct geomagnetic storms (September 08 and
28, 2017) at the same location and other IGS stations covering the Indian
subcontinent using both GPS and NavIC has also been presented. This analysis
revealed similar variations in TEC during the geomagnetic storms of September
2017, indicating the suitability of NavIC to study space weather events along
with the ionospheric studies over the Indian subcontinent.Comment: 38 Pages, 16 Figures, Accepted for publication in Advances in Space
Researc
Prevalence of obesity and its correlates in school going adolescents of Haldwani, Nainital, Uttarakhand, India
Background: With a rising trend of Non-Communicable Diseases (NCDs) in the present world, overweight and obesity has gained importance as it is not only a disease in itself but also risk factor for majority of other NCDs. A dramatic increase in overweight and obesity among children and adolescent has raised the concern of various public health physicians especially in developing country like India. Aims & Objective: To study the prevalence of overweight and obesity & its correlates among school going adolescents of Haldwani block. Material & Methods: School based cross sectional study was done among the adolescents of 8th to 12th standard. To calculate the maximum sample size prevalence of obesity was assumed to be 50%, taking absolute error of 5%, design effect of 2 and 10% non-response rate the sample was calculated to be 880, rounded off to 900. Samples were collected from 30 clusters/schools using simple random sampling. Data was collected using a pre-designed, semi-structured and pre-tested questionnaire and analyzed by using SPSS version 22. Results: Prevalence of overweight and obesity was 13% (CI = 10.8 - 15.2%). Overweight and obesity was found to be significantly associated with urban area, private school, Socio-economic class I, non-vegetarian diet, physical inactivity and playing videogames, working on laptops and computer on univariate analysis. On applying binary logistic regression factors like private schools, socioeconomic class I, non-vegetarian diet and physical inactivity were again found to be significantly associated with overweight and obesity. Conclusion: Prevalence of obesity was found to be more in adolescents having modifiable risk factors.
 
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