435 research outputs found
PEMBUATAN PROTOTIPE OTOMATISASI PENGOLAHAN DATA KAFE DAN KARAOKE BERBASIS MIKROKONTROLER AVR
Karaoke and café are places which often be visited by customer. This
places are very busy and potentially robbing can be happenned. To manage
karaoke and café easier it is neededautomation, so it can work effective and
efficient. The objective of this final project report isto make a managing
automation prototype of Karaoke and café data based on AVR microcontroller.
A managing automation prototype of Karaoke and café data based on
AVR microcontroller has been made. Generally detection of managing
automation prototype of Karaoke and café data based on AVR microcontroller has
designed use 16/32 Atmega, LCD, 4x4 keypad, DC motor, L293D IC, and push
button. For ordering prototype, microcontroller receives input from keypad, than
the result of microcontroller process will show by LCD output and seven
segments. For automatic order serving, microcontroller receives input from push
button, than microcontroller output becomes L293D IC input. The L293D IC
outputs control DC motor. At door security, microcontroller processeson LCD
output and IC L293D, IC L293D control DC motor. At billing karaoke,
microcontroller receives input from the push button, and outputwill be displayed
as seven segments. This prototype makes managing karaoke and cafe easier, save
the time and energy.
It can be concluded that m anaging automation prototype of karaoke and
café data based on AVR microcontroller can be used as real managing automation
prototype of karaoke and café data
Inverse flux quantum periodicity of magnetoresistance oscillations in two-dimensional short-period surface superlattices
Transport properties of the two-dimensional electron gas (2DEG) are
considered in the presence of a perpendicular magnetic field and of a {\it
weak} two-dimensional (2D) periodic potential modulation in the 2DEG plane. The
symmetry of the latter is rectangular or hexagonal. The well-known solution of
the corresponding tight-binding equation shows that each Landau level splits
into several subbands when a rational number of flux quanta pierces the
unit cell and that the corresponding gaps are exponentially small. Assuming the
latter are closed due to disorder gives analytical wave functions and
simplifies considerably the evaluation of the magnetoresistivity tensor
. The relative phase of the oscillations in and
depends on the modulation periods involved. For a 2D modulation
with a {\bf short} period nm, in addition to the Weiss oscillations
the collisional contribution to the conductivity and consequently the tensor
show {\it prominent peaks when one flux quantum passes
through an integral number of unit cells} in good agreement with recent
experiments. For periods nm long used in early experiments, these
peaks occur at fields 10-25 times smaller than those of the Weiss oscillations
and are not resolved
Phase Transitions of Hard Disks in External Periodic Potentials: A Monte Carlo Study
The nature of freezing and melting transitions for a system of hard disks in
a spatially periodic external potential is studied using extensive Monte Carlo
simulations. Detailed finite size scaling analysis of various thermodynamic
quantities like the order parameter, its cumulants etc. are used to map the
phase diagram of the system for various values of the density and the amplitude
of the external potential. We find clear indication of a re-entrant liquid
phase over a significant region of the parameter space. Our simulations
therefore show that the system of hard disks behaves in a fashion similar to
charge stabilized colloids which are known to undergo an initial freezing,
followed by a re-melting transition as the amplitude of the imposed, modulating
field produced by crossed laser beams is steadily increased. Detailed analysis
of our data shows several features consistent with a recent dislocation
unbinding theory of laser induced melting.Comment: 36 pages, 16 figure
Shortest paths on systems with power-law distributed long-range connections
We discuss shortest-path lengths on periodic rings of size L
supplemented with an average of pL randomly located long-range links whose
lengths are distributed according to P_l \sim l^{-\xpn}. Using rescaling
arguments and numerical simulation on systems of up to sites, we show
that a characteristic length exists such that for
. For small p we find
that the shortest-path length satisfies the scaling relation
\ell(r,\xpn,p)/\xi = f(\xpn,r/\xi). Three regions with different asymptotic
behaviors are found, respectively: a) \xpn>2 where , b)
1<\xpn<2 where 0<\theta_s(\xpn)<1/2 and, c) \xpn<1 where
behaves logarithmically, i.e. . The characteristic length is
of the form with \nu=1/(2-\xpn) in region b), but depends
on L as well in region c). A directed model of shortest-paths is solved and
compared with numerical results.Comment: 10 pages, 10 figures, revtex4. Submitted to PR
Commensurate and Incommensurate Vortex Lattice Melting in Periodic Pinning Arrays
We examine the melting of commensurate and incommensurate vortex lattices
interacting with square pinning arrays through the use of numerical
simulations. For weak pinning strength in the commensurate case we observe an
order-order transition from a commensurate square vortex lattice to a
triangular floating solid phase as a function of temperature. This floating
solid phase melts into a liquid at still higher temperature. For strong pinning
there is only a single transition from the square pinned lattice to the liquid
state. For strong pinning in the incommensurate case, we observe a multi-stage
melting in which the interstitial vortices become mobile first, followed by the
melting of the entire lattice, consistent with recent imaging experiments. The
initial motion of vortices in the incommensurate phase occurs by an exchange
process of interstitial vortices with vortices located at the pinning sites. We
have also examined the vortex melting behavior for higher matching fields and
find that a coexistence of a commensurate pinned vortex lattice with an
interstitial vortex liquid occurs while at higher temperatures the entire
vortex lattice melts. For triangular arrays at incommensurate fields higher
than the first matching field we observe that the initial vortex motion can
occur through a novel correlated ring excitation where a number of vortices can
rotate around a pinned vortex. We also discuss the relevance of our results to
recent experiments of colloidal particles interacting with periodic trap
arrays.Comment: 8 figure
Velocity-force characteristics of an interface driven through a periodic potential
We study the creep dynamics of a two-dimensional interface driven through a
periodic potential using dynamical renormalization group methods. We find that
the nature of weak-drive transport depends qualitatively on whether the
temperature is above or below the equilibrium roughening transition
temperature . Above , the velocity-force characteristics is Ohmic,
with linear mobility exhibiting a jump discontinuity across the transition. For
, the transport is highly nonlinear, exhibiting an interesting
crossover in temperature and weak external force . For intermediate drive,
, we find near a power-law velocity-force characteristics
, with , and well-below ,
, with . In the limit
of vanishing drive () the velocity-force characteristics crosses over
to , and is controlled by soliton nucleation.Comment: 18 pages, submitted to Phys. Rev.
Environmental Electrokinetics for a sustainable subsurface
International audienceSoil and groundwater are key components in the sustainable management of the subsurface environment. Source contamination is one of its main threats and is commonly addressed using established remediation techniques such as in-situ chemical oxidation (ISCO), in-situ chemical reduction (ISCR; most notably using zero-valent iron [ZVI]), enhanced in-situ bioremediation (EISB), phytoremediation, soil-washing, pump-and-treat, soil vapour extraction (SVE), thermal treatment, and excavation and disposal. Decades of field applications have shown that these techniques can successfully treat or control contaminants in higher permeability subsurface materials such as sands, but achieve only limited success at sites where low permeability soils, such as silts and clays, prevail. Electrokinetics (EK), a soil remediation technique mostly recognized in in-situ treatment of low permeability soils, has, for the last decade, been combined with more conventional techniques and can significantly enhance the performance of several of these remediation technologies, including ISCO, ISCR, EISB and phytoremediation. Herein, we discuss the use of emerging EK techniques in tandem with conventional remediation techniques, to achieve improved remediation performance. Furthermore, we highlight new EK applications that may come to play a role in the sustainable treatment of the contaminated subsurface
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