1,650 research outputs found

    Perancangan Sistem Informasi Administrasi Surat Berbasis Desktop pada Kantor Notaris Hoiril Masuli, Sh, M.Kn

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    Pada Kantor Notaris Hoiril Masuli, Sh, M.Kn dalam pengelolaan penerimaan berkas masih menggunakan cara manual dan belum terkomputerisasi. Hal ini meyulitkan pegawai dalam pengelolaan data klien, seperti halnya dalam penyimpanan data-data yang masih disimpan dalam bentuk berkas sehingga menyulitkan pegawai dalam mencari data berkas masuk dari klien ataupun berkas yang sudah selesai dibuat serta berkas yang sudah diambil klien. Untuk mengatasi masalah-masalah yang dihadapi, untuk mempercepat pekerjaan dan memudahkan pengelolahaan data perlu adanya sistem yang terkomputerisasi dalam pengelolaan berkas klien. Pada penelitian ini metode yang digunakan adalah berorientasi objek, model penelitian yang digunakan adalah Waterfall serta tools yang digunakan adalah UML (Unified Model Language)

    On equalities involving integrals of the logarithm of the Riemann ζ-function and equivalent to the Riemann hypothesis

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    By using the generalized Littlewood theorem about a contour integral involving the logarithm of an analytic function, we show how an infinite number of integral equalities involving integrals of the logarithm of the Riemann ζ-function and equivalent to the Riemann hypothesis can be established and present some of them as an example. It is shown that all earlier known equalities of this type, viz., the Wang equality, Volchkov equality, Balazard-Saias-Yor equality, and an equality established by one of the authors, are certain special cases of our general approac

    Hopping on the Bethe lattice: Exact results for densities of states and dynamical mean-field theory

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    We derive an operator identity which relates tight-binding Hamiltonians with arbitrary hopping on the Bethe lattice to the Hamiltonian with nearest-neighbor hopping. This provides an exact expression for the density of states (DOS) of a non-interacting quantum-mechanical particle for any hopping. We present analytic results for the DOS corresponding to hopping between nearest and next-nearest neighbors, and also for exponentially decreasing hopping amplitudes. Conversely it is possible to construct a hopping Hamiltonian on the Bethe lattice for any given DOS. These methods are based only on the so-called distance regularity of the infinite Bethe lattice, and not on the absence of loops. Results are also obtained for the triangular Husimi cactus, a recursive lattice with loops. Furthermore we derive the exact self-consistency equations arising in the context of dynamical mean-field theory, which serve as a starting point for studies of Hubbard-type models with frustration.Comment: 14 pages, 9 figures; introduction expanded, references added; published versio

    Local Pheromone Release from Dynamic Polarity Sites Underlies Cell-Cell Pairing during Yeast Mating.

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    Cell pairing is central for many processes, including immune defense, neuronal connection, hyphal fusion, and sexual reproduction. How does a cell orient toward a partner, especially when faced with multiple choices? Fission yeast Schizosaccharomyces pombe P and M cells, which respectively express P and M factor pheromones [1, 2], pair during the mating process induced by nitrogen starvation. Engagement of pheromone receptors Map3 and Mam2 [3, 4] with their cognate pheromone ligands leads to activation of the Gα protein Gpa1 to signal sexual differentiation [3, 5, 6]. Prior to cell pairing, the Cdc42 GTPase, a central regulator of cell polarization, forms dynamic zones of activity at the cell periphery at distinct locations over time [7]. Here we show that Cdc42-GTP polarization sites contain the M factor transporter Mam1, the general secretion machinery, which underlies P factor secretion, and Gpa1, suggesting that these are sub-cellular zones of pheromone secretion and signaling. Zone lifetimes scale with pheromone concentration. Computational simulations of pair formation through a fluctuating zone show that the combination of local pheromone release and sensing, short pheromone decay length, and pheromone-dependent zone stabilization leads to efficient pair formation. Consistently, pairing efficiency is reduced in the absence of the P factor protease. Similarly, zone stabilization at reduced pheromone levels, which occurs in the absence of the predicted GTPase-activating protein for Ras, leads to reduction in pairing efficiency. We propose that efficient cell pairing relies on fluctuating local signal emission and perception, which become locked into place through stimulation

    Enumeration of simple random walks and tridiagonal matrices

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    We present some old and new results in the enumeration of random walks in one dimension, mostly developed in works of enumerative combinatorics. The relation between the trace of the nn-th power of a tridiagonal matrix and the enumeration of weighted paths of nn steps allows an easier combinatorial enumeration of the paths. It also seems promising for the theory of tridiagonal random matrices .Comment: several ref.and comments added, misprints correcte

    Conformal invariance studies of the Baxter-Wu model and a related site-colouring problem

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    The partition function of the Baxter-Wu model is exactly related to the generating function of a site-colouring problem on a hexagonal lattice. We extend the original Bethe ansatz solution of these models in order to obtain the eigenspectra of their transfer matrices in finite geometries and general toroidal boundary conditions. The operator content of these models are studied by solving numerically the Bethe-ansatz equations and by exploring conformal invariance. Since the eigenspectra are calculated for large lattices, the corrections to finite-size scaling are also calculated.Comment: 12 pages, latex, to appear in J. Phys. A: Gen. Mat

    On the Square Root of a Bell Matrix

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    AbstractIn the context of Riordan arrays, the problem of determining the square root of a Bell matrix R=R(f(t)/t, f(t))R={\mathcal {R}}(f(t)/t,\ f(t)) R = R ( f ( t ) / t , f ( t ) ) defined by a formal power series f(t)=k0fktkf(t)=\sum _{k \ge 0}f_kt^k f ( t ) = ∑ k ≥ 0 f k t k with f(0)=f0=0f(0)=f_0=0 f ( 0 ) = f 0 = 0 is presented. It is proved that if f(0)=1f^\prime (0)=1 f ′ ( 0 ) = 1 and f(0)0f^{\prime \prime }(0)\ne 0 f ″ ( 0 ) ≠ 0 then there exists another Bell matrix H=R(h(t)/t, h(t))H={\mathcal {R}}(h(t)/t,\ h(t)) H = R ( h ( t ) / t , h ( t ) ) such that HH=R;H*H=R; H ∗ H = R ; in particular, function h(t) is univocally determined by a symbolic computational method which in many situations allows to find the function in closed form. Moreover, it is shown that function h(t) is related to the solution of Schröder's equation. We also compute a Riordan involution related to this kind of matrices

    Analysis of algorithms as a teaching experience

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    C-Finite Sequences and Riordan Arrays

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    Many prominent combinatorial sequences, such as the Fibonacci, Lucas, Pell, Jacobsthal and Tribonacci sequences, are defined by homogeneous linear recurrence relations with constant coefficients. These sequences are often referred to as C-finite sequences, and a variety of representations have been employed throughout the literature, largely influenced by the author’s background and the specific application under consideration. Beyond the representation through recurrence relations, other approaches include those based on generating functions, explicit formulas, matrix exponentiation, the method of undetermined coefficients and several others. Among these, the generating function approach is particularly prevalent in enumerative combinatorics due to its versatility and widespread use. The primary objective of this work is to introduce an alternative representation grounded in the theory of Riordan arrays. This representation provides a general formula expressed in terms of the vectors of constants and initial conditions associated with any recurrence relation of a given order, offering a new perspective on the structure of such sequences

    Critical and off-critical studies of the Baxter-Wu model with general toroidal boundary conditions

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    The operator content of the Baxter-Wu model with general toroidal boundary conditions is calculated analytically and numerically. These calculations were done by relating the partition function of the model with the generating function of a site-colouring problem in a hexagonal lattice. Extending the original Bethe-ansatz solution of the related colouring problem we are able to calculate the eigenspectra of both models by solving the associated Bethe-ansatz equations. We have also calculated, by exploring the conformal invariance at the critical point, the mass ratios of the underlying massive theory governing the Baxter-Wu model in the vicinity of its critical point.Comment: 32 pages latex, to appear in J. Phys. A: Math. Ge
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