Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
10,204
result(s) for
"Shubham"
Sort by:
Some results on Ricci-Bourguignon solitons and almost solitons
We prove some results for the solitons of the Ricci–Bourguignon flow, generalizing the corresponding results for Ricci solitons. Taking motivation from Ricci almost solitons, we then introduce the notion of Ricci–Bourguignon almost solitons and prove some results about them that generalize previous results for Ricci almost solitons. We also derive integral formulas for compact gradient Ricci–Bourguignon solitons and compact gradient Ricci–Bourguignon almost solitons. Finally, using the integral formula, we show that a compact gradient Ricci–Bourguignon almost soliton is isometric to a Euclidean sphere if it has constant scalar curvature or its associated vector field is conformal.
Journal Article
Hardy and Rellich inequality on lattices
In this paper, we study the asymptotic behaviour of the sharp constant in discrete Hardy and Rellich inequality on the lattice
Z
d
as
d
→
∞
. In the process, we proved some Hardy-type inequalities for the operators
Δ
m
and
∇
(
Δ
m
)
for non-negative integers
m
on a
d
dimensional torus. It turns out that the sharp constant in discrete Hardy and Rellich inequality grows as
d
and
d
2
respectively as
d
→
∞
.
Journal Article
Correction to: On the Unique Solvability of the Absolute Value Equation
In this note, we give the two counterexamples for two unique solvability conditions that appeared in the published paper by Wu et al. (J Optim Theory Appl 169:705–712, 2016).
Journal Article
A revolution in obesity treatment
Mounting evidence, including the recent (and unprecedented) phase 2 data on retatrutide, supports a role for incretin hormone agonists in treating obesity. But with great power comes great responsibility.
Journal Article
Acoustic Emission (AE) Based Damage Quantification and Its Relation with AE-Based Micromechanical Coupled Damage Plasticity Model for Intact Rocks
The existing micromechanical damage plasticity models assume that penny-shaped microcracks are present in the rocks, but it is seldom a reality. These models result in the abstract values of the damage variable. It is fundamentally due to the assumption of penny-shaped microcracks. To overcome this limitation, we have modified the micromechanical damage plasticity model such that the damage variable obtained from the proposed constitutive model relates to the measured damage from the recorded Acoustic Emission (AE) signals. This research presents a micromechanical coupled damage plasticity model by utilising AE data to predict the nonlinear mechanical response of intact rocks under Conventional Triaxial Compression (CTC) loading. The novelty of the proposed model is that it overcomes the limitation of penny-shaped microcracks and accounts for arbitrarily shaped microcracks by using a phenomenological approach. The applicability of the proposed model is shown by different rocks originating from varying geology. We have modelled the nonlinear mechanical behaviour of rock salt and coal (sedimentary rocks), tuff (soft igneous rock), and marble (hard metamorphic rock). The model performance is verified by comparing the results with the test data using the coefficient of determination (R2) statistical parameter. The proposed model predicts well the experimental data of damage variables with strain. It also successfully presents both strain hardening and softening behaviour of the rocks.HighlightsThe article contributes to the modification of the micromechanical coupled damage plasticity model such that the damage variable of the model relates to the experimentally obtained damage by Acoustic Emissions.The proposed model uses a phenomenological approach to account for arbitrarily shaped microcracks in the micromechanical coupled damage plasticity constitutive model.The proposed model is verified on different rocks with diverse geological genesis, such as rock salt, coal (sedimentary rocks), tuff (soft igneous rock), and marble (hard metamorphic rock) under uniaxial and triaxial compression loading conditions.
Journal Article
Dietary Polyphenols and Their Role in Oxidative Stress-Induced Human Diseases: Insights Into Protective Effects, Antioxidant Potentials and Mechanism(s) of Action
Dietary polyphenols including phenolic acids, flavonoids, catechins, tannins, lignans, stilbenes, and anthocyanidins are widely found in grains, cereals, pulses, vegetables, spices, fruits, chocolates, and beverages like fruit juices, tea, coffee and wine. In recent years, dietary polyphenols have gained significant interest among researchers due to their potential chemopreventive/protective functions in the maintenance of human health and diseases. It is believed that dietary polyphenols/flavonoids exert powerful antioxidant action for protection against reactive oxygen species (ROS)/cellular oxidative stress (OS) towards the prevention of OS-related pathological conditions or diseases. Pre-clinical and clinical evidence strongly suggest that long term consumption of diets rich in polyphenols offer protection against the development of various chronic diseases such as neurodegenerative diseases, cardiovascular diseases (CVDs), cancer, diabetes, inflammatory disorders and infectious illness. Increased intake of foods containing polyphenols (for example, quercetin, epigallocatechin-3-gallate, resveratrol, cyanidin etc.) has been claimed to reduce the extent of a majority of chronic oxidative cellular damage, DNA damage, tissue inflammations, viral/bacterial infections, and neurodegenerative diseases. It has been suggested that the antioxidant activity of dietary polyphenols plays a pivotal role in the prevention of OS-induced human diseases. In this narrative review, the biological/pharmacological significance of dietary polyphenols in the prevention of and/or protection against OS-induced major human diseases such as cancers, neurodegenerative diseases, CVDs, diabetes mellitus, cancer, inflammatory disorders and infectious diseases have been delineated. This review specifically focuses a current understanding on the dietary sources of polyphenols and their protective effects including mechanisms of action against various major human diseases.
Journal Article
Grindability of carbon fiber reinforced polymer using CNT biological lubricant
Carbon fiber-reinforced polymer (CFRP) easily realizes the integrated manufacturing of components with high specific strength and stiffness, and it has become the preferred material in the aerospace field. Grinding is the key approach to realize precision parts and matching the positioning surface for assembly and precision. Hygroscopicity limits the application of flood lubrication in CFRP grinding, and dry grinding leads to large force, surface deterioration, and wheel clogging. To solve the above technical bottleneck, this study explored the grindability and frictional behavior of CNT biological lubricant MQL through grinding experiments and friction-wear tests. Results showed that the CNT biological lubricant reduced the friction coefficient by 53.47% compared with dry condition, showing optimal and durable antifriction characteristics. The new lubrication was beneficial to suppressing the removal of multifiber block debris, tensile fracture, and tensile-shear fracture, with the advantages of tribological properties and material removal behavior, the tangential and normal grinding force, and the specific grinding energy were reduced by 40.41%, 31.46%, and 55.78%, respectively, compared with dry grinding. The proposed method reduced surface roughness and obtained the optimal surface morphology by preventing burrs, fiber pull-out, and resin smearing, and wheel clogging was prevented by temperature reduction and lubricating oil film formation.
S
a
and
S
q
of the CNT biological lubricant were reduced by 8.4% and 7.9%, respectively, compared with dry grinding. This study provides a practical basis for further application of CNT biological lubricant in CFRP grinding.
Journal Article
Enhanced harmony search algorithm with non-linear control parameters for global optimization and engineering design problems
Harmony search algorithm (HSA), inspired by the behaviors of music improvisation process, is a widely used metaheuristic to solve global optimization problems arises in various fields. The reason of its popularity is its simplicity of algorithm structure and good performance. However, the conventional harmony search algorithm (HSA) experiences prone towards the local optima, tedious task of tuning parameters, and premature convergence. To overcome all these drawbacks of conventional HSA and further improve the precision of numerical results, a new variant of the HSA called modified harmony search algorithm (MHSA) is proposed in the present study. This MHSA utilizes the valuable information stored in the harmony memory and modifies the search strategy to make an efficient search procedure by adopting a new formulation to the pitch adjustment process, randomization process, harmony memory considering rate (HMCR), and pitch adjustment rate (PAR). The experimental validation and comparative performance study with conventional HSA, variants of HSA such as adaptive harmony search with best based search strategy (ABHS), enhanced self-adaptive global-best harmony search (ESGHS), novel self-adaptive harmony search (NSHS), parameter adaptive harmony search (PAHS), Gaussian global-best harmony search algorithm (GGHS) and other metaheuristics such as sine cosine algorithm (SCA), grey wolf optimizer (GWO), comprehensive learning particle swarm optimization (CLPSO), gbest-guided artificial bee colony (GABC), and covariance matrix adaptation evolution strategy (CMA-ES) is conducted on a set of 23 well-known benchmark problems. In addition to this benchmarking, the proposed MHSA is also used to solve three structural engineering design problem. The statistical test and convergence behaviour analysis are used to analyze the quality of search and significance of improved accuracy. The comparison illustrates the superior search efficiency of the proposed MHSA than other algorithms as a global optimizer.
Journal Article
Advancements in reliability estimation for the exponentiated Pareto distribution: a comparison of classical and Bayesian methods with lower record values
Estimating the reliability of multicomponent systems is crucial in various engineering and reliability analysis applications. This paper investigates the multicomponent stress strength reliability estimation using lower record values, specifically for the exponentiated Pareto distribution. We compare classical estimation techniques, such as maximum likelihood estimation, with Bayesian estimation methods. Under Bayesian estimation, we employ Markov Chain Monte Carlo techniques and Tierney–Kadane’s approximation to obtain the posterior distribution of the reliability parameter. To evaluate the performance of the proposed estimation approaches, we conduct a comprehensive simulation study, considering various system configurations and sample sizes. Additionally, we analyze real data to illustrate the practical applicability of our methods. The proposed methodologies provide valuable insights for engineers and reliability analysts in accurately assessing the reliability of multicomponent systems using lower record values.
Journal Article