First and second order clustering transitions for a system with infinite-range attractive interaction

We consider a Hamiltonian system made of $N$ classical particles moving in two dimensions, coupled via an {\it infinite-range interaction} gauged by a parameter $A$. This system shows a low energy phase with most of the particles trapped in a unique cluster. At higher energy it exhibits a transition towards a homogenous phase. For sufficiently strong coupling $A$ an intermediate phase characterized by two clusters appears. Depending on the value of $A$ the observed transitions can be either second or first order in the canonical ensemble. In the latter case microcanonical results differ dramatically from canonical ones. However, a canonical analysis, extended to metastable and unstable states, is able to describe the microcanonical equilibrium phase. In particular, a microcanonical negative specific heat regime is observed in the proximity of the transition whenever it is canonically discontinuous. In this regime, {\it microcanonically stable} states are shown to correspond to {\it saddles} of the Helmholtz free energy, located inside the spinodal region.Comment: 4 pages, Latex - 3 EPS Figs - Submitted to Phys. Rev.

KASCADE: Astrophysical results and tests of hadronic interaction models

KASCADE is a multi-detector setup to get redundant information on single air shower basis. The information is used to perform multiparameter analyses to solve the threefold problem of the reconstruction of (i)the unknown primary energy, (ii) the primary mass, and (iii) to quantify the characteristics of the hadronic interactions in the air-shower development. In this talk recent results of the KASCADE data analyses are summarized concerning cosmic ray anisotropy studies, determination of flux spectra for different primary mass groups, and approaches to test hadronic interaction models. Neither large scale anisotropies nor point sources were found in the KASCADE data set. The energy spectra of the light element groups result in a knee-like bending and a steepening above the knee. The topology of the individual knee positions shows a dependency on the primary particle. Though no hadronic interaction model is fully able to describe the multi-parameter data of KASCADE consistently, the more recent models or improved versions of older models reproduce the data better than few years ago.Comment: to appear in Nucl. Phys. B (Proc. Suppl.), Proc. of the XIII ISVHECRI, Pylos 2004 - with a better quality of the figure

Anomalous diffusion as a signature of collapsing phase in two dimensional self-gravitating systems

A two dimensional self-gravitating Hamiltonian model made by $N$ fully-coupled classical particles exhibits a transition from a collapsing phase (CP) at low energy to a homogeneous phase (HP) at high energy. From a dynamical point of view, the two phases are characterized by two distinct single-particle motions : namely, superdiffusive in the CP and ballistic in the HP. Anomalous diffusion is observed up to a time $\tau$ that increases linearly with $N$. Therefore, the finite particle number acts like a white noise source for the system, inhibiting anomalous transport at longer times.Comment: 10 pages, Revtex - 3 Figs - Submitted to Physical Review

Rancang Bangun Sistem Infromasi Pengukuran Kesehatan Laporan Keuangan pada Perusahaan Jasa (Studi Kasus Perusahaan Jasa yang Terdaftar di BEI)

Pertumbuhan ekonomi Indonesia dalam beberapa waktu terakhir masuk ke dalam peringkat ketiga tertinggi di dunia di bawah China dan India. Setiap jenis usaha yang tetap dan terus menerus yang didirikan untuk bekerja dan berdudukan dalam Negara Republik Indonesia ber tujuan memperoleh keuntungan atau laba. Untuk mengetahui keuntungan atau laba setiap Perusahaan dibutuhkan laporan keuangan.Penelitian ini bertujuan untuk merancang suatu aplikasi perhitungan laporan keuangan perbankan yang memiliki fitur manajemen user yang dapat menampilkan output berupa laporan keuangan, daftar bank yang digunakan untuk menampilkan hasil perhitungan dan juga dapat menampilkan grafik tingkat kesehatan keuangan berdasarkan perhitungan sebelumnya.Metode yang digunakan dalam pengukuran kinerja laporan keuangan adalah metode RGEC (Risk Profile, Earnings, Capital) yang terdiri dari rasio, % rasio, peringkat dan kriteria. Dengan bahasa pemrograman PHP, Java Script, HTML dan pengujian sistem menggunakan Black-Box Testing, hasil akhir yang diperoleh dari penelitian ini berupa hasil analisis laporan keuangan dan grafik tingkat kesehatan laporan keuangan Perusahaan

Model Gaya Kepemimpinan Yang Mempengaruhi Kinerja Bawahan

Gaya kepemimpinan dalam sebuah proyek konstruksi memegang peranan penting dalam mencapai tujuan proyek. Gaya kepememimpinan dan pengaruhnya terhadap bawahan berbeda-beda bagi setiap individu. Dalam penelitian ini, penulis membandingkan antara gaya kepemimpinan dan inovasi gaya kepemimpinan dalam mempengaruhi kinerja bawahan. Penulis menggunakan kuisioner dengan sistem skala likert untuk mengetahui seberapa besar pengaruh pengaruh setiap indikator dari gaya kepemimpinan, inovasi gaya kepemimpinan dan kinerja bawahan. Tujuannya adalah untuk menentukan faktor– faktor yang dapat mempengaruhi gaya kepemimpinan, menentukan faktor – faktor yang dapat mempengaruhi inovasi keterampilan kepemimpinan, menentukan faktor – faktor yang dapat mempengaruhi kinerja bawahan, serta membuat sebuah model gaya kepemimpinan yang mempengaruhi kinerja bawahan yang terdiri dari gaya kepemimpinan, inovasi keterampilan kepemimpinan, dan kinerja bawahan

Dissecting the knee - Air shower measurements with KASCADE

Recent results of the KASCADE air shower experiment are presented in order to shed some light on the astrophysics of cosmic rays in the region of the knee in the energy spectrum. The results include investigations of high-energy interactions in the atmosphere, the analysis of the arrival directions of cosmic rays, the determination of the mean logarithmic mass, and the unfolding of energy spectra for elemental groups

Solvable model of a phase oscillator network on a circle with infinite-range Mexican-hat-type interaction

We describe a solvable model of a phase oscillator network on a circle with infinite-range Mexican-hat-type interaction. We derive self-consistent equations of the order parameters and obtain three non-trivial solutions characterized by the rotation number. We also derive relevant characteristics such as the location-dependent distributions of the resultant frequencies of desynchronized oscillators. Simulation results closely agree with the theoretical ones

The KASCADE-Grande Experiment and the LOPES Project

KASCADE-Grande is the extension of the multi-detector setup KASCADE to cover a primary cosmic ray energy range from 100 TeV to 1 EeV. The enlarged EAS experiment provides comprehensive observations of cosmic rays in the energy region around the knee. Grande is an array of 700 x 700 sqm equipped with 37 plastic scintillator stations sensitive to measure energy deposits and arrival times of air shower particles. LOPES is a small radio antenna array to operate in conjunction with KASCADE-Grande in order to calibrate the radio emission from cosmic ray air showers. Status and capabilities of the KASCADE-Grande experiment and the LOPES project are presented.Comment: To appear in Nuclear Physics B, Proceedings Supplements, as part of the volume for the CRIS 2004, Cosmic Ray International Seminar: GZK and Surrounding

Cosmic Ray Energy Spectra and Mass Composition at the Knee - Recent Results from KASCADE -

Recent results from the KASCADE experiment on measurements of cosmic rays in the energy range of the knee are presented. Emphasis is placed on energy spectra of individual mass groups as obtained from an two-dimensional unfolding applied to the reconstructed electron and truncated muon numbers of each individual EAS. The data show a knee-like structure in the energy spectra of light primaries (p, He, C) and an increasing dominance of heavy ones (A > 20) towards higher energies. This basic result is robust against uncertainties of the applied interaction models QGSJET and SIBYLL which are used in the shower simulations to analyse the data. Slight differences observed between experimental data and EAS simulations provide important clues for further improvements of the interaction models. The data are complemented by new limits on global anisotropies in the arrival directions of CRs and by upper limits on point sources. Astrophysical implications for discriminating models of maximum acceleration energy vs galactic diffusion/drift models of the knee are discussed based on this data.Comment: 8 pages, 7 figures, to appear in Nuclear Physics B, Proceedings Supplements, as part of the volume for the CRIS 2004, Cosmic Ray International Seminar: GZK and Surrounding

To what extent can dynamical models describe statistical features of turbulent flows?

Statistical features of "bursty" behaviour in charged and neutral fluid turbulence, are compared to statistics of intermittent events in a GOY shell model, and avalanches in different models of Self Organized Criticality (SOC). It is found that inter-burst times show a power law distribution for turbulent samples and for the shell model, a property which is shared only in a particular case of the running sandpile model. The breakdown of self-similarity generated by isolated events observed in the turbulent samples, is well reproduced by the shell model, while it is absent in all SOC models considered. On this base, we conclude that SOC models are not adequate to mimic fluid turbulence, while the GOY shell model constitutes a better candidate to describe the gross features of turbulence.Comment: 14 pages, 4 figures, in press on Europhys. Lett. (may 2002