9,190 research outputs found
Penerapan Metode Profile Matching untuk Menentukan Peserta Lomba Pramuka
Perkembangan zaman menuntut manusia untuk menguasai ilmu pengetahuan. Terutama untuk meraih prestasi sebagai pelajar, khususnya untuk melanjutkan ke jenjang selanjutnya /jalur prestasi, Untuk mendapatkan sebuah prestasi sangatlah tidak mudah, salah satunya dibidang lomba kepramukaan, butuh USAha dan latihan yang keras, serta seleksi yang ketat untuk menjadi peserta lomba SMK Negeri 1 Kota Bogor. Maka dari itu diperlukan suatu sistem yang dapat memperhitungkan segala kriteria yang mendukung dalam pengambilan keputusan calon peserta lomba. Pengambilan keputusan dengan menggunakan Metode Profile Matching merupakan hal yang tepat untuk menseleksi siswa apakah cocok untuk lomba dibidang tertentu. Hasil keputusan dari sistem profile matching berdasarkan nilai akhir dari penelitian, menyatakan bahwa jika nilai probabilitas YA lebih besar dari probabilitas TIDAK, maka sistem bekerja dengan baik, sebaliknya jika nilai probabilitas TIDAK lebih tinggi dari probabilitas YA, maka sistem tidak bekerja dengan baik. Dari hasil penelitian untuk unjuk kerja sistem profile matching masuk dalam kategori âLayakâ. Nilai persentase hasil pengujian pada sistem untuk setiap faktor, yaitu: functionality sebesar 69 %, efficiency sebesar 70 %, dan USAbility sebesar 65%. Persentase total dari kualitas sistem adalah 90% (Layak)
Automatic transmission: ethnicity, racialization and the car
YesThis article is based on ethnographic research carried out in Bradford, an ethnically diverse city situated in the north of England. The sample of over 60 participants mostly comprises males of British Pakistani Muslim heritage but varies in terms other markers of identity such as social class, profession and residential/working locale. The article analyses the cultural value and meaning of cars within a multicultural context and how a consumer object can feed into the processes which refine and embed racialized identities. Small cases studies reveal the concrete and discursive ways through which ideas around identity and ethnicity are transmitted and how, in particular, racialization continues to feature as a live, active and recognisable process in everyday experience
Yang-Mills condensate dark energy coupled with matter and radiation
The coincidence problem is studied for the dark energy model of effective
Yang-Mills condensate in a flat expanding universe during the matter-dominated
stage. The YMC energy is taken to represent the dark energy, which
is coupled either with the matter, or with both the matter and the radiation
components. The effective YM Lagrangian is completely determined by quantum
field theory up to 1-loop order. It is found that under very generic initial
conditions and for a variety of forms of coupling, the existence of the scaling
solution during the early stages and the subsequent exit from the scaling
regime are inevitable. The transition to the accelerating stage always occurs
around a redshift . Moreover, when the Yang-Mills
condensate transfers energy into matter or into both matter and radiation, the
equation of state of the Yang-Mills condensate can cross over -1 around
, and takes on a current value . This is consistent with
the recent preliminary observations on supernovae Ia. Therefore, the
coincidence problem can be naturally solved in the effective YMC dark energy
models.Comment: 24 pages, 18 figure
Photons from Quark Gluon Plasma and Hot Hadronic Matter
The productions of real photons from quark gluon plasma and hot hadronic
matter formed after the nucleus - nucleus collisions at ultra-relativistic
energies are discussed. The effects of the spectral shift of the hadrons at
finite temperature on the production of photons are investigated. On the basis
of the present analysis it is shown that the photon spectra measured by WA98
collaboration in Pb + Pb collisions at CERN SPS energies can be explained by
both QGP as well as hadronic initial states if the spectral shift of hadrons at
finite temperature is taken into account. Several other works on the analysis
of WA98 photon data have also been briefly discussed.Comment: Latex file, six eps figures include
Recent progress in the development of few mode fiber amplifier
We review the performances of both core and cladding pumped few-mode erbium doped fiber amplifiers supporting 6 spatial modes (4 mode groups) which incidentally the highest mode count demonstrated to date
Chameleon field and the late time acceleration of the universe
In the present work, it is shown that a chameleon scalar field having a
nonminimal coupling with dark matter can give rise to a smooth transition from
a decelerated to an accelerated phase of expansion for the universe. It is
surprising to note that the coupling with the chameleon scalar field hardly
affects the evolution of the dark matter sector, which still redshifts as
.Comment: 7 pages, 2 figure
Enskog Theory for Polydisperse Granular Mixtures. I. Navier-Stokes order Transport
A hydrodynamic description for an -component mixture of inelastic, smooth
hard disks (two dimensions) or spheres (three dimensions) is derived based on
the revised Enskog theory for the single-particle velocity distribution
functions. In this first portion of the two-part series, the macroscopic
balance equations for mass, momentum, and energy are derived. Constitutive
equations are calculated from exact expressions for the fluxes by a
Chapman-Enskog expansion carried out to first order in spatial gradients,
thereby resulting in a Navier-Stokes order theory. Within this context of small
gradients, the theory is applicable to a wide range of restitution coefficients
and densities. The resulting integral-differential equations for the zeroth-
and first-order approximations of the distribution functions are given in exact
form. An approximate solution to these equations is required for practical
purposes in order to cast the constitutive quantities as algebraic functions of
the macroscopic variables; this task is described in the companion paper.Comment: 36 pages, to be published in Phys. Rev.
Sfermion Pair Production in Polarized and Unpolarized Collisions
We calculate total and differential cross sections for the production of
sfermion pairs in photon-photon collisions, including contributions from
resolved photons and arbitrary photon polarization. Sfermion production in
photon collisions depends only on the sfermion mass and charge. It is thus
independent of the details of the SUSY breaking mechanism, but highly sensitive
to the sfermion charge. We compare the total cross sections for bremsstrahlung,
beamstrahlung, and laser backscattering photons to those in
annihilation. We find that the total cross section at a polarized photon
collider is larger than the annihilation cross section up to the
kinematic limit of the photon collider.Comment: 19 pages, Latex, 18 (e)ps-figure
Equilibration in Quark Gluon Plasma
The hydrodynamic expansion rate of quark gluon plasma (QGP) is evaluated and
compared with the scattering rate of quarks and gluons within the system.
Partonic scattering rates evaluated within the ambit of perturbative Quantum
Choromodynamics (pQCD) are found to be smaller than the expansion rate
evaluated with ideal equation of state (EoS) for the QGP. This indicate that
during the space-time evolution the system remains out of equilibrium.
Enhancement of pQCD cross sections and a more realistic EoS keep the partons
closer to the equilibrium.Comment: To be published in the Quark Matter 2008 poster proceeding
Are direct photons a clean signal of a thermalized quark gluon plasma?
Direct photon production from a quark gluon plasma (QGP) in thermal
equilibrium is studied directly in real time. In contrast to the usual S-matrix
calculations, the real time approach is valid for a QGP that formed and reached
LTE a short time after a collision and of finite lifetime ( as expected at RHIC or LHC). We point out that during such
finite QGP lifetime the spectrum of emitted photons carries information on the
initial state. There is an inherent ambiguity in separating the virtual from
the observable photons during the transient evolution of the QGP. We propose a
real time formulation to extract the photon yield which includes the initial
stage of formation of the QGP parametrized by an effective time scale of
formation . This formulation coincides with the S-matrix approach
in the infinite lifetime limit. It allows to separate the virtual cloud as well
as the observable photons emitted during the pre- equilibrium stage from the
yield during the QGP lifetime. We find that the lowest order contribution
which does \emph{not} contribute to the S-matrix
approach, is of the same order of or larger than the S-matrix contribution
during the lifetime of the QGP for a typical formation time . The yield for momenta features a
power law fall-off and is larger than that obtained
with the S-matrix for momenta . We provide a
comprehensive numerical comparison between the real time and S-matrix yields
and study the dynamics of the build-up of the photon cloud and the different
contributions to the radiative energy loss. The reliability of the current
estimates on photon emission is discussed.Comment: 31 pages, 12 eps figures, version to appear in PR
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