We provide a strategy for the exact inference of the average as well as the fluctuations of the entropy production in nonequilibrium systems in the steady state, from the measurements of arbitrary ...current fluctuations. Our results are built upon the finite-time generalization of the thermodynamic uncertainty relation, and require only very short time series data from experiments. We illustrate our results with exact and numerical solutions for two colloidal heat engines.
Full text
Available for:
CMK, CTK, FMFMET, NUK, UL
We extend the "institutional voids" perspective on business groups by examining the value-adding potential of two of the characteristic features of business groups: their diverse portfolio and ...multientity organizational form. We maintain that portfolio diversity affords affiliates privileged access to opportunities hidden by incomplete strategic factor markets. We hypothesize that the multientity organizational form enables superior sensing and seizing of these growth opportunities by affiliate firms. We further suggest that, in the context of institutional reforms, these characteristics strengthen business group affiliates' ability to capitalize on the expanded set of opportunities made available by the reform program. Empirical analyses on a sample of Indian firms over the period 1994-2010 support our hypotheses. Implications for theory and future directions are discussed.
The origin of macroscopic irreversibility from microscopically time-reversible dynamical laws-often called the arrow-of-time problem-is of fundamental interest in both science and philosophy. ...Experimentally probing such questions in quantum theory requires systems with near-perfect isolation from the environment and long coherence times. Ultracold atoms are uniquely suited to this task. We experimentally demonstrate a striking parallel between the statistical irreversibility of wavefunction collapse and the arrow of time problem in the weak measurement of the quantum spin of an atomic cloud. Our experiments include statistically rare events where the arrow of time is inferred backward; nevertheless we provide evidence for absolute irreversibility and a strictly positive average arrow of time for the measurement process, captured by a fluctuation theorem. We further demonstrate absolute irreversibility for measurements performed on a quantum many-body entangled wavefunction-a unique opportunity afforded by our platform-with implications for studying quantum many-body dynamics and quantum thermodynamics.
Nanoscale machines are strongly influenced by thermal fluctuations, contrary to their macroscopic counterparts. As a consequence, even the efficiency of such microscopic machines becomes a ...fluctuating random variable. Using geometric properties and the fluctuation theorem for the total entropy production, a "universal theory of efficiency fluctuations" at long times, for machines with a finite state space, was developed by Verley et al. Nat. Commun. 5, 4721 (2014)NCAOBW2041-172310.1038/ncomms5721; Phys. Rev. E 90, 052145 (2014)PRESCM1539-375510.1103/PhysRevE.90.052145. We extend this theory to machines with an arbitrary state space. Thereby, we work out more detailed prerequisites for the "universal features" and explain under which circumstances deviations can occur. We also illustrate our findings with exact results for two nontrivial models of colloidal engines.
Full text
Available for:
CMK, CTK, FMFMET, NUK, UL
•In this research work the prediction of diabetes is made using grey wolf optimization technique is implemented.•The dataset is taken from UCI repository and the name of the dataset is PIMA INDIAN ...DIABETIC dataset.•In order to predict the diabetes disease, Fuzzy rules are combined with grey wolf optimization technique.•The methodology has three layers of decision-making named as (α),(β), (δ) along with fuzzy rules to make a prediction.•The performance of the proposed algorithm gives better result than the existing algorithm.
Diabetes disease increased with a high rate due to unhealthy lifestyle, work culture, and lacking of physical activity. Diabetes is an incurable and chronic disease but early sugar monitoring and diagnosis prevent from the harmful effects. In this research work diabetes prediction model is presented which is based on the grey wolf optimization with fuzzy logics. This work has been done by using the concept of artificial intelligence in which model learns the fuzzy rule and then optimized according to the GWO algorithm.
A recent work A. Lapolla and A. Godec, Phys. Rev. Lett. 125, 110602 (2020) showed that among a pair of thermodynamically equidistant quenches from a colder and a hotter initial state at a fixed ...ambient temperature, the relaxation from the colder initial state (uphill relaxation) is always faster, for dynamics close to stable minima. Here we show that this is not generically the case for open quantum systems with two or three energy levels. We find that both faster uphill and faster downhill relaxation and symmetric thermal relaxation can be observed in equidistant quenches, depending on the transition rates and the choice of the distance measure used. Furthermore, we obtain a phase diagram in the parameter space for the three-level system corresponding to different thermalization behaviors.
Full text
Available for:
CMK, CTK, FMFMET, NUK, UL
Here we explore the possibility of precise time keeping in quantum systems using athermal resources. We show that quantum measurement engineered reservoirs can be used as athermal resources to drive ...the ticks of a quantum clock. Two- and three-level quantum systems act as transducers in our model, converting the quantum measurement-induced noise to produce a series of ticks. The ticking rate of the clock is maximized when the measured observable maximally noncommutes with the clock's Hamiltonian. We use the large deviation principle to characterize the statistics of observed ticks within a given time period and show that it can be sub-Poissonian - quantified by Mandel's Q parameter - alluding to the quantum nature of the clock. We discuss the accuracy and efficiency of the clock, and extend our framework to include hybrid quantum clocks fueled by both measurements, and thermal resources. We make comparisons to relatable recent proposals for quantum clocks, and discuss alternate device implementations harvesting the quantum measurement engineered nonequilibrium conditions, beyond the clock realization.
Full text
Available for:
CMK, CTK, FMFMET, NUK, UL
Display omitted
•Silicalite-1 with intracrystalline nanovoids was prepared using corn stem pith powder.•The prepared silicalite-1 possessed larger external surface area and led to higher dispersion ...of heteropoly acid.•31P-MAS NMR and XPS results indicated interfacial bond formation between support and heteropoly acid.•The supported catalyst showed better catalytic activity in esterification of levulinic acid.•The catalyst was stable even after four recycles and no leaching of heteropoly acid observed.
Silicalite-1, a silicious zeolite having intracrystalline nanovoids in addtion to its intrinsic micropores was prepared under hydrothermal condition using corn stem pith powder as a hard template. The zeolite was used as a support for 12-phosphotungstic acid (HPA) and the resulted catalyst was characterized using powder X-ray diffraction, N2 adsorption, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, 31P − magic angle spinning nuclear magnetic resonance spectroscopy (31P-MAS NMR), X-ray photoelelctron spectroscopy, ultraviolet-visible spectroscopy and temperature programmed desorption of ammonia. Supporting HPA on the zeolite containing nanovoids improved dispersion of HPA and hence increased the number of accessible acid sites. X-ray photoelectron and 31P-MAS NMR spectra indicated interfacial bond formation between the zeolite surface and HPA. The supported HPA was tested as a hetergeneous catalyst for esterifiation of levulinic acid with 1-propanol, 1-butanol and 1-heptanol. Heteropoly acid supported on the zeolite with intracrytalline nanovoids exhibited enhanced catalytic activity and the activity was stable even after four recycles.
The viability of unrelated diversification as a strategy in emerging economies is an unresolved puzzle. Because business groups dominate the landscape in these economies, and are known to diversify ...either by expanding the scope of existing affiliate firms and/or setting up new firms, we argue that it is important to make a distinction between firm‐level and business group‐level diversification. The results of our study covering the 15‐year period following India’s economic liberalization confirm our thesis. Whereas all firms, including business group affiliates, reduced unrelated scope to negotiate product and capital market pressures, business groups took advantage of the opportunity‐rich, post‐reform environment to enter into new unrelated businesses by setting up new affiliates. Our findings echo suggestions that as institutions strengthen, the locus of unrelated diversification moves away from managers of public corporations to entities with different types of ownership structures. We present the business group as one such ownership structure.
PDF
