Study of Pakistan pilot project farmer-leaders to Nepal

Farmer participation / Irrigation management / Farmer managed irrigation systems / Irrigated farming / Sustainable agriculture / Institution building / Pakistan

Slave spin cluster mean field theory away from half-filling: Application to the Hubbard and the extended Hubbard Model

A new slave-spin representation of fermion operators has recently been proposed for the half-filled Hubbard model. We show that with the addition of a gauge variable, the formalism can be extended to finite doping. The resulting spin problem can be solved using the cluster mean-field approximation. This approximation takes short-range correlations into account by exact diagonalization on the cluster, whereas long-range correlations beyond the size of clusters are treated at the mean-field level. In the limit where the cluster has only one site and the interaction strength $U$ is infinite, this approach reduces to the Gutzwiller approximation. There are some qualitative differences when the size of the cluster is finite. We first compute the critical $U$ for the Mott transition as a function of a frustrating second-neighbor interaction on lattices relevant for various correlated systems, namely the cobaltites, the layered organic superconductors and the high-temperature superconductors. For the triangular lattice, we also study the extended Hubbard model with nearest-neighbor repulsion. In additionto a uniform metallic state, we find a $\sqrt(3) \times \sqrt(3)$ charge density wave in a broad doping regime, including commensurate ones. We find that in the large $U$ limit, intersite Coulomb repulsion $V$ strongly suppresses the single-particle weight of the metallic state.Comment: 10 pages, 11 figures, submitted to PR

Scale-free network topology and multifractality in weighted planar stochastic lattice

We propose a weighted planar stochastic lattice (WPSL) formed by the random sequential partition of a plane into contiguous and non-overlapping blocks and find that it evolves following several non-trivial conservation laws, namely $\sum_i^N x_i^{n-1} y_i^{4/n-1}$ is independent of time $\forall \ n$, where $x_i$ and $y_i$ are the length and width of the $i$th block. Its dual on the other hand, obtained by replacing each block with a node at its center and common border between blocks with an edge joining the two vertices, emerges as a network with a power-law degree distribution $P(k)\sim k^{-\gamma}$ where $\gamma=5.66$ revealing scale-free coordination number disorder since $P(k)$ also describes the fraction of blocks having $k$ neighbours. To quantify the size disorder, we show that if the $i$th block is populated with $p_i\sim x_i^3$ then its distribution in the WPSL exhibits multifractality.Comment: 7 pages, 8 figures, To appear in New Journal of Physics (NJP

Proposed business plan for pilot farmer organizations: Extended project on Farmer Managed Irrigated Agriculture in LBOD Project Area of Sindh Province

Farmers' associations / Farmer managed irrigation systems / Irrigation programs / Irrigation management / Drainage / Economic aspects / Income / Operating costs / Maintenance costs / Conflict

An Assessment of Air Quality in and around Gwagwalada Abattoir, Gwagwalada, Abuja, Fct.

This work attempted an assessment of air quality in and around Gwagwalada abattoir. Air samples were collected from six points around the abattoir and recorded insitu for analysis.  The following parameters were investigated; Particulate Matter (PM), Carbon monoxide (CO), Sulphur dioxide (SO2), Nitrogen dioxide (NO2), Ammonia (NH3), Chlorine (CL2) and Hydrogen cyanide. The statistical test employed was the Student t-test in verifying the hypothesis. Based on the data collected and the analysis made, it was observed that the mean values of the parameters varied from points to points and at different time of the day. Also, the mean values of the parameters were compared with the FEPA recommended limits, and it was observed that Sulphur dioxide (SO2), Nitrogen dioxide (NO2) and Particulate matter were above the FEPA recommended limit. While Carbon monoxide (CO), Hydrogen cyanide (HCN) and Ammonia (NH3) are still below the standard limit. Air Quality Index shows that Sulphur dioxide (SO2), and  Nitrogen dioxide (NO2 have very poor quality index Recommendations include; relocation of abattoir to an area far from residences, inspection of abattoir process by professionals in related fields, proper waste management systems should be made. Keywords: Air, Quality, AQI, Abattoir, pollution, and Gwagwalad

Coordinated Generation and Transmission Maintenance Scheduling Considering Network Constraints via GGDF and ODF

This paper proposes a coordinated generation and transmission maintenance scheduling by incorporating network constraints. The main advantage of the proposed approach is that maintenance is scheduled at the optimal period of the lowest possible operating cost while satisfying all the specified constraints. In this approach, sensitivity factors (GGDFs and ODFs) which are based on DC approximation are applied to calculate the line flows in normal and maintenance conditions. They are applied due to their simplicity, linearity, physical comprehension and rapidity of computation. To simulate the effect of network constraint on maintenance schedule and operating cost, several cases are studied with and without transmission limit constraints. To ensure the accuracy of these sensitivity factors, power flows on each line are compared with the one obtained from a PSSE simulator. The result shows that generators and transmission lines are scheduled at periods that satisfy the transmission capacity limit

Fractal dimension and degree of order in sequential deposition of mixture

We present a number models describing the sequential deposition of a mixture of particles whose size distribution is determined by the power-law $p(x) \sim \alpha x^{\alpha-1}$, $x\leq l$ . We explicitly obtain the scaling function in the case of random sequential adsorption (RSA) and show that the pattern created in the long time limit becomes scale invariant. This pattern can be described by an unique exponent, the fractal dimension. In addition, we introduce an external tuning parameter beta to describe the correlated sequential deposition of a mixture of particles where the degree of correlation is determined by beta, while beta=0 corresponds to random sequential deposition of mixture. We show that the fractal dimension of the resulting pattern increases as beta increases and reaches a constant non-zero value in the limit $\beta \to \infty$ when the pattern becomes perfectly ordered or non-random fractals.Comment: 16 pages Latex, Submitted to Phys. Rev.