3,771 research outputs found
Synthesis of Some New Thienylazetidinones and Thiazolidinones Containing Pyrazolines
Condensation of thiophene-2-carboxa.ldehyde with 4-aminoacetophenone
gave a quantitative yield of 4-(thienylideneamino)acetophenone(
I). Condensation of I with aromatic aldehydes yielded
the corresponding 4-( 4-substituted-phenyl)-4\u27 -(2-thienyleneamino )chalcone(
II). Interaction of II with hydrazines gave 3-(4-2\u27-thienylideneamino)
phenylpyrazolines (III, IV). Cyclocondensation of
chloroacetyl chloride (or mercaptoa cetic acid) on III or IV gave
3-chloro-1-( 4-pheny lpyrazolin-3\u27 -yl)-4-(2" - thieny l)azetidin -2- ones
(V, VI) and 3-(4-phenylpyrazolin-3\u27-yl)-2-(2"-thienyl)thiazolidin-4-
-ones (VII, VIII), respectivel
Generalized -conformal change and special Finsler spaces
In this paper, we investigate the change of Finslr metrics which we refer to as a
generalized -conformal change. Under this change, we study some special
Finsler spaces, namely, quasi C-reducible, semi C-reducible, C-reducible,
-like, -like and -like Finsler spaces. We also obtain the
transformation of the T-tensor under this change and study some interesting
special cases. We then impose a certain condition on the generalized
-conformal change, which we call the b-condition, and investigate the
geometric consequences of such condition. Finally, we give the conditions under
which a generalized -conformal change is projective and generalize some
known results in the literature.Comment: References added, some modifications are performed, LateX file, 24
page
The Casimir force in noncommutative Randall-Sundrum models
In this paper we study the effect of spacetime noncommutativity in the
5-dimensional Randall-Sundrum brane worlds on the Casimir force acting on a
pair of parallel plates. We show that the presence of a noncommutative scale
length affects the nature of the Casimir force for small plate separation.
Using accurate experimental bounds for the Casimir force in parallel plate
geometry, we find an upper bound for the noncommutative cutoff of the order of
TeV, and that the size of the interbrane distance in RSI model is
approximately given by and for
GeV and GeV, respectively.Comment: 20 pages, 5 figures, accepted for publication in Phys. Rev.
Consistency, Amplitudes and Probabilities in Quantum Theory
Quantum theory is formulated as the only consistent way to manipulate
probability amplitudes. The crucial ingredient is a consistency constraint: if
there are two different ways to compute an amplitude the two answers must
agree. This constraint is expressed in the form of functional equations the
solution of which leads to the usual sum and product rules for amplitudes. A
consequence is that the Schrodinger equation must be linear: non-linear
variants of quantum mechanics are inconsistent. The physical interpretation of
the theory is given in terms of a single natural rule. This rule, which does
not itself involve probabilities, is used to obtain a proof of Born's
statistical postulate. Thus, consistency leads to indeterminism.
PACS: 03.65.Bz, 03.65.Ca.Comment: 23 pages, 3 figures (old version did not include the figures
Some entanglement features of three-atoms Tavis-Cummings model: Cooperative case
In this paper we consider a system of identical three two-level atoms
interacting at resonance with a single-mode of the quantized field in a
lossless cavity. The initial cavity field is prepared in the coherent state
while the atoms are taken initially to be either in the uppermost excited state
"" or The -state or the -state. For this
system we investigate different kinds of atomic inversion and entanglement,
which arise between the different parts of the system due to the interaction.
Also the relationship, between entanglement and some other nonclassical effects
in the statistical properties, such as collapses and revivals in the atomic
inversion where superharmonic effects appear, is discussed. The -functions
for different cases are discussed. Most remarkably it is found that the
-state is more robust against energy losses, showing almost
coherent trapping and Schr\"odinger-cat states can not be produced from such
state. Also the entanglement of -state is more robust than the
-state. Another interesting feature found is that the state which
has no pairwise entanglement initially will have a much improvement of such
pairwise entanglement through the evolution. Sudden death and sudden revival of
atoms-pairwise entanglement are produced with the -state.Comment: 14 pages, 7 figure
THE ROLE OF ARTIFICIAL INTELLIGENCE AND MACHINE LEARNING IN PRESERVING CULTURAL HERITAGE AND ART WORKS VIA VIRTUAL RESTORATION
Artifacts including paintings, drawings, prints, mosaics, sculptures, historical structures and monuments, as well as archaeological sites present a key part of our cultural heritage. It consists of Intangible culture (such as folklore, traditions, language, and knowledge), tangible culture (such as buildings, monuments, landscapes, archival materials, books, works of art, and artifacts), and natural heritage (such as biodiversity and culturally significant landscapes) .Now we will concentrate on tangible culture and its problems and how to handle them. One of its biggest problems is that over the years the nature of the materials used in the creation of the artwork make them prone to cracks, fractures, stains, and colors fading and blurring. The causes of their damage could be of natural or human- related reasons. The natural causes range from war, fires, earthquakes, natural disasters and the human-related causes range from accidental events like to pollution which results of climate changes, which like acid rain. It is a must to consider the environment in which you store your artwork. Our regular environment's light, heat, moisture, and pollution levels can lead to harmful chemical and physical reactions in artwork. There are several reasons why it is necessary to preserve ancient works of art. The fact that it enables us to comprehend the historical and cultural context of the era in which it was made is one of the key factors. Then preserving our artworks is a must and this can be done by manual techniques or using machine learning algorithms
Timing Driven Genetic Algorithm for Placement
In this paper we present a timing -driven placer for standard-cell IC design. The placement algorithm follows the genetic pradigm. At early generations, the search is biased towards solutions with superior timing characteristics. As the algorithm starts converging towards generations with acceptable delay properties, the objective is dynamically adjusted towards optimizing area and routability. Experiments with test circuits demonstrate delay performance improvement by upto 20%. Without any noticeable loss in solution quality, sizebale reduction in runtime is obtained when population size is allowed to decrease in a controlled manner whenever the search hits a plateau
Performance Driven Standard-cell Placement Using the Genetic Algorithm
Current placement systems attempt to optimize several objectives, namely area, connection lenght, and timing performance. In this paper we present a timing-driven placer for standard-cell IC design. The placement algorithm follows the genetic paradigm. Besides optimizing for area and wire length, the placer minimizes the propogation delays on a predicted set of critical paths. The paths are enumerated using a new approach based on the notion of criticality. Experiments with test circuits demonstrate delay performance improvement by upto 20
Producing ice cream with concentrated cactus pear pulp: A preliminary study
Abstract Red cactus pear (Opuntia ficus-indica) pulp was tested for some technological and chemical characteristics. The pulp was concentrated up to 30°Brix then added at four levels (0, 5, 10 and 15%) to basic ice cream mix. The basic mix contained 0.5% gelatin, 8% fat and 10.5% milk solids non-fat (MSNF), and 16% sucrose. Some of rheological parameters of both mixes and resultant ice cream samples, in addition to some technological characteristics of resultant ice cream samples were measured. The rheological properties of all ice cream mixes before and after aging showed that the flow behavior of mixes is non-Newtonian besides being pseudoplastic behavior. While specific gravity and weight per gallon of resultant ice cream samples increased by increasing of added pulp, overrun decreased. Sensory evaluation of resultant ice cream samples showed that sample with 5% cactus was very desirable and very close to control sample. This work shows the possibility of producing a new product of ice cream using cactus pear pulp as a good fruit substitute
Shallow geophysical techniques to investigate the groundwater table at the Great Pyramids of Giza, Egypt
The near-surface groundwater aquifer that threatened the Great
Pyramids of Giza, Egypt, was investigated using integrated geophysical
surveys. A total of 10 electrical resistivity imaging, 26Â shallow seismic
refraction, and 19Â ground-penetrating radar surveys were conducted in the Giza
Plateau. Collected data for each method were evaluated by state-of-the art
processing and modeling techniques. A three-layer model depicts the
subsurface layers and better delineates the groundwater aquifer and water
table elevation. The resistivity of the aquifer layer and seismic velocity vary
between 40 and 80 Ίm and between 1500 and 2500 m sâ1, respectively. The average water table elevation is about
+15 m, which is safe for the Great Sphinx, but it is still subjected to potential
hazards from the Nazlet El-Samman suburb where the water table elevation
reaches 17 m. A shallower water table at the Valley Temple and the tomb of Queen
Khentkawes,
with a low topographic relief, represents severe hazards. It can be concluded that
a perched groundwater table is detected in the elevated topography to the west and
southwest that might be due to runoff and capillary seepage.</p
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