911 research outputs found

    Estimation of attractive and repulsive interactions from the fluctuation observables at RHIC using van der Waals hadron resonance gas Model

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    Experimental data on the moments of net-proton distribution in central Au-Au collisions for various center of mass energies (sNN\sqrt{\mathrm {s_{NN}}}) measured by the STAR collaboration at the Relativistic Heavy-Ion Collider (RHIC) are compared to the corresponding results from a van der Waals type interacting hadron resonance gas (VDWHRG) model. The parameters representing the attractive and repulsive interactions in the VDWHRG model have been extracted by fitting the σ2\sigma^{2}/MM, Sσ\it{S}\sigma and κσ2\kappa\sigma^{2}, where MM is the mean, σ\sigma is the standard deviation, S\it{S} is the skewness and κ\kappa the kurtosis of the net-proton distribution. Considering all the three moment products we observe that the strength of the repulsive interactions increases with decrease in sNN\sqrt{\mathrm {s_{NN}}} = 200 to 19.6 GeV while the strength of the attractive interaction is of the similar magnitude. For sNN\sqrt{\mathrm {s_{NN}}} = 11.5 and 7.7 GeV there is drop in the strength of both attractive and repulsive interactions relative to sNN\sqrt{\mathrm {s_{NN}}} = 19.6 GeV. On the other hand, if we consider only the higher order moment products, Sσ\it{S}\sigma and κσ2\kappa\sigma^{2}, which are more sensitive to critical point physics, a segregation with respect to the strength of the attractive parameter is observed. The data for sNN\sqrt{\mathrm {s_{NN}}} = 19.6 and 27 GeV supports a larger attractive strength compared to other energies. For this latter case, the repulsive interaction values are of similar order for most of the beam energies studied, except for 7.7 GeV where the parameter value is not well constrained due to large uncertainties

    Transport coefficients for multi-component gas of hadrons using Chapman Enskog method

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    The transport coefficients of a multi-component hadronic gas at zero and non-zero baryon chemical potential are calculated using the Chapman-Enskog method. The calculations are done within the framework of an SS-matrix based interacting hadron resonance gas model. In this model, the phase-shifts and cross-sections are calculated using KK-matrix formalism and where required, by parameterizing the experimental phase-shifts. Using the energy dependence of cross-section, we find the temperature dependence of various transport coefficients such as shear viscosity, bulk viscosity, heat conductivity and diffusion coefficient. We finally compare our results regarding various transport coefficients with previous results in the literature

    Risk of Financing Agriculture in the North-Eastern Hill Region of India with Special Reference to Meghalaya

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    The study pertains to the economic issues of risk and uncertainties associated with financing hill agriculture from the twin angles of risk of farmers to utilize the credit and of bankers to disburse the agricultural loan. The issues discussed are: first, why the financial institutions are reluctant to lend agricultural advances? Second, whether the farm income or rate of return on equity and non-equity capital is sufficient to repay the loan? Third, what are the major sources and the magnitude of risks and uncertainties associated with hill farming? Fourth, nature of agricultural marketing situation and how it affects the farm income in this region and finally, the possibilities have been explored, where and how the agricultural lending can be stepped up with positive economic return? The study has revealed that agricultural farming in north-east region of India is severely constrained by high risk and uncertainty arising out from various factors. Under the prevailing condition the expectation of a steady and assured income from agriculture is quite limited; hence, the hill farming fails to attract considerable private investment. The prevailing risk and uncertainty situation compels them to operate at low-input and low-output subsistence farming with low volume of marketable surplus. It has been found that the financial institutions face difficulty in financing the hill agriculture in view of low repayment performance and increasing non-performing assets for agricultural loan. Also, the absence/poor performance of crop insurance scheme (presently only Meghalaya and Sikkim are implementing the National Agricultural Insurance Scheme) increases the risk of hill farming considerably. Non-availability of reliable agricultural database (time series as well as cross section) on area, production and yield, cost of cultivation has been found the major impediments for implementing the crop insurance scheme efficiently. The agricultural situation in this region is highly heterogeneous; variability is extremely high even within a few kilometres of area. It has been suggested that suitable methodologies followed by a wide database be developed to estimate the yield and cost of production of horticultural crops which will help policymakers to formulate right policy to protect the interest of farmers as well as smooth functioning of all stakeholders — entrepreneurs, private investors, bankers and crop insurance implementing agencies.Agricultural and Food Policy,

    Residential Demand Side Management model, optimization and future perspective: A review

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    The residential load sector plays a vital role in terms of its impact on overall power balance, stability, and efficient power management. However, the load dynamics of the energy demand of residential users are always nonlinear, uncontrollable, and inelastic concerning power grid regulation and management. The integration of distributed generations (DGs) and advancement of information and communication technology (ICT) even though handles the related issues and challenges up to some extent, till the flexibility, energy management and scheduling with better planning are necessary for the residential sector to achieve better grid stability and efficiency. To address these issues, it is indispensable to analyze the demand-side management (DSM) for the complex residential sector considering various operational constraints, objectives, identifying various factors that affect better planning, scheduling, and management, to project the key features of various approaches and possible future research directions. This review has been done based on the related literature to focus on modeling, optimization methods, major objectives, system operation constraints, dominating factors impacting overall system operation, and possible solutions enhancing residential DSM operation. Gaps in future research and possible prospects have been discussed briefly to give a proper insight into the current implementation of DSM. This extensive review of residential DSM will help all the researchers in this area to innovate better energy management strategies and reduce the effect of system uncertainties, variations, and constraints
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