7,045 research outputs found
Reynolds number effect on the velocity increment skewness in isotropic turbulence
Second and third order longitudinal structure functions and wavenumber
spectra of isotropic turbulence are computed using the EDQNM model and compared
to results of the multifractal formalism. At the highest Reynolds number
available in windtunnel experiments, , both the multifractal
model and EDQNM give power-law corrections to the inertial range scaling of the
velocity increment skewness. For EDQNM, this correction is a finite Reynolds
number effect, whereas for the multifractal formalism it is an intermittency
correction that persists at any high Reynolds number. Furthermore, the two
approaches yield realistic behavior of second and third order statistics of the
velocity fluctuations in the dissipative and near-dissipative ranges.
Similarities and differences are highlighted, in particular the Reynolds number
dependence
A possible cosmological application of some thermodynamic properties of the black body radiation in dimensional Euclidean spaces
In this work we present the generalization of some thermodynamic properties
of the black body radiation (BBR) towards an dimensional Euclidean space.
For this case the Planck function and the Stefan-Boltzmann law have already
been given by Landsberg and de Vos and some adjustments by Menon and Agrawal.
However, since then no much more has been done on this subject and we believe
there are some relevant aspects yet to explore. In addition to the results
previously found we calculate the thermodynamic potentials, the efficiency of
the Carnot engine, the law for adiabatic processes and the heat capacity at
constant volume. There is a region at which an interesting behavior of the
thermodynamic potentials arise, maxima and minima appear for the BBR
system at very high temperatures and low dimensionality, suggesting a possible
application to cosmology. Finally we propose that an optimality criterion in a
thermodynamic framework could have to do with the nature of the universe.Comment: 9 pages, 8 figure
Statistical analysis of 22 public transport networks in Poland
Public transport systems in 22 Polish cities have been analyzed. Sizes of
these networks range from N=152 to N=2881. Depending on the assumed definition
of network topology the degree distribution can follow a power law or can be
described by an exponential function. Distributions of paths in all considered
networks are given by asymmetric, unimodal functions. Clustering, assortativity
and betweenness are studied. All considered networks exhibit small world
behavior and are hierarchically organized. A transition between dissortative
small networks N=500 is observed.Comment: 11 pages, 17 figures, 2 tables, REVTEX4 forma
Optical conductivity in non-equilibrium d-wave superconductors
We consider the optical conductivity of a d-wave BCS superconductor in the
presence of a non-equilibrium distribution of excess quasiparticles. Two
different simplified models used in the past for the s-wave case are considered
and results compared. In the -model of Parker the excess quasiparticles
are assumed to be in a thermal distribution at some temperature larger
than the equilibrium sample temperature. In the - model of Owen and
Scalapino a chemical potential is introduced to accommodate the excess
quasiparticles. Some of the results obtained are specific to the model, most
are qualitatively similar in both.Comment: 11 pages, 6 figures this manuscript has been accepted for publication
in abbreviated form by Physical Review
Rancang Bangun Sistem Informasi Kepegawaian (Studi Kasus : PT Dekatama Centra)
Human Resources (HR) are element or very important asset in the company. Human Resource Management is a process to deal with the issues on the scope of employees, managers and other workers to be able to support the activities to achieve the predetermined goals. The development of science and technology at this time brings a lot of benefits and services, for example, computer helps to perform data processing in a systematic, statistical data processing and others. Therefore, this research has built HRM aplication using waterfall method. The data collection uses interview and observation methods. This HRM application describes the interaction between user and application system, which each user has different access rights tailored to job functions. In addition, this application can be attributed to the Hardware Finger Print originating from a different place or location.The softwares used to build the systems were HTML, PHP, Javascript, css, and MySQL while the blackbox method was used to test the information system. The HRM application is expected to help the processing of employee data, so that the HRD division works more effectively and efficiently. HRM application can display employee data, employee history, length of employment, labor contracts, attendance data, payroll data, salary recapitulation, receipt of salary, employee benefits, salary increment, leave application, chunks of cash receipt and setting work hours. Keywords— HRM, Fingerprint, Salary
Mapping the cellular electrophysiology of rat sympathetic preganglionic neurones to their roles in cardiorespiratory reflex integration:A whole cell recording study in situ
Sympathetic preganglionic neurones (SPNs) convey sympathetic activity flowing from the CNS to the periphery to reach the target organs. Although previous in vivo and in vitro cell recording studies have explored their electrophysiological characteristics, it has not been possible to relate these characteristics to their roles in cardiorespiratory reflex integration. We used the working heart–brainstem preparation to make whole cell patch clamp recordings from T3–4 SPNs (n = 98). These SPNs were classified by their distinct responses to activation of the peripheral chemoreflex, diving response and arterial baroreflex, allowing the discrimination of muscle vasoconstrictor-like (MVC(like), 39%) from cutaneous vasoconstrictor-like (CVC(like), 28%) SPNs. The MVC(like) SPNs have higher baseline firing frequencies (2.52 ± 0.33 Hz vs. CVC(like) 1.34 ± 0.17 Hz, P = 0.007). The CVC(like) have longer after-hyperpolarisations (314 ± 36 ms vs. MVC(like) 191 ± 13 ms, P < 0.001) and lower input resistance (346 ± 49 MΩ vs. MVC(like) 496 ± 41 MΩ, P < 0.05). MVC(like) firing was respiratory-modulated with peak discharge in the late inspiratory/early expiratory phase and this activity was generated by both a tonic and respiratory-modulated barrage of synaptic events that were blocked by intrathecal kynurenate. In contrast, the activity of CVC(like) SPNs was underpinned by rhythmical membrane potential oscillations suggestive of gap junctional coupling. Thus, we have related the intrinsic electrophysiological properties of two classes of SPNs in situ to their roles in cardiorespiratory reflex integration and have shown that they deploy different cellular mechanisms that are likely to influence how they integrate and shape the distinctive sympathetic outputs
Pengembangan Sistem Informasi Penjadwalan Dan Manajemen Keuangan Kegiatan Seminar Dan Sidang Skripsi/Tugas Akhir (Studi Kasus Program Studi Sistem Informasi UNIKOM)
Saat ini penerapan teknologi informasi banyak dimanfaatkan dalam berbagai bidang, tidak terkecuali pada bidang pendidikan. Pada sebuah instansi pendidikan tentunya sangat membutuhkan sistem informasi dalam mengatur kegiatan akademik yang cepat, efektif, efisien, akurat untuk meningkatkan standar mutu pendidikan pada instansi pendidikan tersebut. Kegiatan akademik, terutama pada kegiatan penjadwalan dan manajemen keuangan untuk seminar dan sidang tugas akhir / skripsi di Program studi Sistem Informasi UNIKOM perlu didukung oleh sistem infomasi berbasis teknologi informasi yang dapat memudahkan kegiatan tersebut. Permasalahan yang terjadi saat ini antara lain pembuatan jadwal yang memakan waktu yanglama dan sering kali terjadi bentrok, hingga proses perhitungan honorarium yang masih dilakukan secara manual sehingga beresiko terjadinya kesalahan perhitungan. Penelitian diawali dengan studi literatur, pengumpula data, perancangan, pengujian, dan penyajian perangkat lunak. Dengan adanya SISPMK (Sistem Informasi Penjadwalan dan Manajemen Keuangan) dapat membantu kegiatan penjadwalan kegiatan seminar dan sidang skripsi / tugas akhir menjadi lebih mudah, meminimalisir resiko terjadinya bentrok antar dosen maupun ruangan kelas dan perhitungan honorarium dan pelapoan keuangan kegiatan seminar dan sidang skripsi / tugas akhirmenjadi lebih cepat. Kata Kunci— Sistem Informasi, Penjadwalan, Manajemen Keuangan, Skripsi dan Tugas Akhir
Magnetically Driven Accretion in the Kerr Metric III: Unbound Outflows
We have carried out fully relativistic numerical simulations of accretion
disks in the Kerr metric. In this paper we focus on the unbound outflows that
emerge self-consistently from the accretion flow. These outflows are found in
the axial funnel region and consist of two components: a hot, fast, tenuous
outflow in the axial funnel proper, and a colder, slower, denser jet along the
funnel wall. Although a rotating black hole is not required to produce these
unbound outflows, their strength is enhanced by black hole spin. The
funnel-wall jet is excluded from the axial funnel due to elevated angular
momentum, and is also pressure-confined by a magnetized corona. The tenuous
funnel outflow accounts for a significant fraction of the energy transported to
large distances in the higher-spin simulations. We compare the outflows
observed in our simulations with those seen in other simulations.Comment: 33 pages, 8 figures, ApJ submitte
Circumventricular organ apelin receptor knockdown decreases blood pressure and sympathetic drive responses in the spontaneously hypertensive rat
The central site(s) mediating the cardiovascular actions of the apelin-apelin receptor (APJ) system remains a major question. We hypothesized that the sensory circumventricular organs (CVOs), interfacing between the circulation and deeper brain structures, are sites where circulating apelin acts as a signal in the central nervous system to decrease blood pressure (BP). We show that APJ gene (aplnr) expression was elevated in the CVOs of spontaneously hypertensive rats (SHRs) compared to normotensive Wistar Kyoto (WKY) controls, and that there was a greater mean arterial BP (MABP) decrease following microinjection of [Pyr(1)]apelin-13 to the CVOs of SHRs compared to WKY rats. Lentiviral APJ-specific-shRNA (LV-APJ-shRNA) was used to knockdown aplnr expression, both collectively in three CVOs and discretely in individual CVOs, of rats implanted with radiotelemeters to measure arterial pressure. LV-APJ-shRNA-injection decreased aplnr expression in the CVOs and abolished MABP responses to microinjection of [Pyr(1)]apelin-13. Chronic knockdown of aplnr in any of the CVOs, collectively or individually, did not affect basal MABP in SHR or WKY rats. Moreover, knockdown of aplnr in any of the CVOs individually did not affect the depressor response to systemic [Pyr(1)]apelin-13. By contrast, multiple knockdown of aplnr in the three CVOs reduced acute cardiovascular responses to peripheral [Pyr(1)]apelin-13 administration in SHR but not WKY rats. These results suggest that endogenous APJ activity in the CVOs has no effect on basal BP but that functional APJ in the CVOs is required for an intact cardiovascular response to peripherally administered apelin in the SHR
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