17,606 research outputs found
Micromechanics of fatigue in woven and stitched composites
The goal is to determine how microstructural factors, especially the architecture of microstructural factors, control fatigue damage in 3D reinforced polymer composites. Test materials were fabricated from various preforms, including stitched quasi-isotropic laminates, and through-the-thickness angle interlock, layer-to-layer angle interlock, and through-the-thickness stitching effect weaves. Preforms were impregnated with a tough resin by a special vacuum infiltration method. Most tests are being performed in uniaxial compression/compression loading. In all cases to date, failure has occurred not by delamination, but by shear failure, which occurs suddenly rather than by gradual macroscopic crack growth. Some theoretical aspects of bridging are also examined
Topoisomerase activity assays in Neurospora
DNA topoisomerases are enzymes capable of altering the topological conformation of DNA by inducing transient single (Topoisomerase I) and double strand (Topoisomerase II) breaks
Peran Desentralisasi Fiskal Terhadap Kinerja Ekonomi Di Kabupaten/kota Provinsi Jawa Tengah
This research is intended to examine the influence of fiscal decentralization on economic growth, poverty, employment, and welfare at regencies/municipalities level in Central Java Province. Research population consist of 29 regencies and 6 municipalities, employing secondary data from Central Bureau of Statistic of Central Java Province and regencies/municipalities level in Central Java Province within the period of 2001 up to 2005. Data analysis is conducted by using path analysis with AMOS program software. The results of this study indicate that, first fiscal decentralization has a positive and significant effect on economic growth. Second, economic growth has a positive and significant effect on employment rate. Third, economic growth has a negative and significant effect on poverty. Forth, economic growth has a positive and significant effect on welfare. Fifth, employment rate has a negative and significant effect on welfare. Sixth, poverty has a negative and significant effect on welfare at regencies/municipalities level in Central Java Province
Artifacts with uneven sampling of red noise
The vast majority of sampling systems operate in a standard way: at each tick
of a fixed-frequency master clock a digitizer reads out a voltage that
corresponds to the value of some physical quantity and translates it into a bit
pattern that is either transmitted, stored, or processed right away. Thus
signal sampling at evenly spaced time intervals is the rule: however this is
not always the case, and uneven sampling is sometimes unavoidable.
While periodic or quasi-periodic uneven sampling of a deterministic signal
can reasonably be expected to produce artifacts, it is much less obvious that
the same happens with noise: here I show that this is indeed the case only for
long-memory noise processes, i.e., power-law noises with . The resulting artifacts are usually a nuisance although they can be
eliminated with a proper processing of the signal samples, but they could also
be turned to advantage and used to encode information.Comment: 5 figure
Phase transition in a stochastic prime number generator
We introduce a stochastic algorithm that acts as a prime number generator.
The dynamics of such algorithm gives rise to a continuous phase transition
which separates a phase where the algorithm is able to reduce a whole set of
integers into primes and a phase where the system reaches a frozen state with
low prime density. We present both numerical simulations and an analytical
approach in terms of an annealed approximation, by means of which the data are
collapsed. A critical slowing down phenomenon is also outlined.Comment: accepted in PRE (Rapid Comm.
Metal-Ferroelectric-Metal heterostructures with Schottky contacts I. Influence of the ferroelectric properties
A model for Metal-Ferroelectric-Metal structures with Schottky contacts is
proposed. The model adapts the general theories of metal-semiconductor
rectifying contacts for the particular case of metal-ferroelectric contact by
introducing: the ferroelectric polarization as a sheet of surface charge
located at a finite distance from the electrode interface; a deep trapping
level of high concentration; the static and dynamic values of the dielectric
constant. Consequences of the proposed model on relevant quantities of the
Schottky contact such as built-in voltage, charge density and depletion width,
as well as on the interpretation of the current-voltage and capacitance-voltage
characteristics are discussed in detail.Comment: 14 pages with 4 figures, manuscript under revision at Journal of
Applied Physics for more than 1 year (submitted May 2004, first revision
September 2004, second revision May 2005
- …