4,966 research outputs found
New acceleration technique for the backpropagation algorithm
Artificial neural networks have been studied for many years in the hope of achieving human like performance in the area of pattern recognition, speech synthesis and higher level of cognitive process. In the connectionist model there are several interconnected processing elements called the neurons that have limited processing capability. Even though the rate of information transmitted between these elements is limited, the complex interconnection and the cooperative interaction between these elements results in a vastly increased computing power; The neural network models are specified by an organized network topology of interconnected neurons. These networks have to be trained in order them to be used for a specific purpose. Backpropagation is one of the popular methods of training the neural networks. There has been a lot of improvement over the speed of convergence of standard backpropagation algorithm in the recent past. Herein we have presented a new technique for accelerating the existing backpropagation without modifying it. We have used the fourth order interpolation method for the dominant eigen values, by using these we change the slope of the activation function. And by doing so we increase the speed of convergence of the backpropagation algorithm; Our experiments have shown significant improvement in the convergence time for problems widely used in benchmarKing Three to ten fold decrease in convergence time is achieved. Convergence time decreases as the complexity of the problem increases. The technique adjusts the energy state of the system so as to escape from local minima
New species of hybrid pull systems
production models;control systems;simulation
Searching for dark radiation at the LHC
In this work we explore the intriguing connections between searches for
long-lived particles (LLPs) at the LHC and early universe cosmology. We study
the non-thermal production of ultra-relativistic particles (i.e. dark
radiation) in the early universe via the decay of weak-scale LLPs and show that
the cosmologically interesting range
corresponds to LLP decay lengths in the mm to cm range. These decay lengths lie
at the boundary between prompt and displaced signatures at the LHC and can be
comprehensively explored by combining searches for both. To illustrate this
point, we consider a scenario where the LLP decays into a charged lepton and a
(nearly) massless invisible particle. By reinterpreting searches for promptly
decaying sleptons and for displaced leptons at both ATLAS and CMS we can then
directly compare LHC exclusions with cosmological observables. We find that the
CMB-S4 target value of is already excluded by
current LHC searches and even smaller values can be probed for LLP masses at
the electroweak scale.Comment: 15 pages, 4 figure
Application of differential similarity to finding nondimensional groups important in tests of cooled engine components
The method of differential similarity is applied to the partial differential equations and boundary conditions which govern the temperature, velocity, and pressure fields in the flowing gases and the solid stationary components in air-cooled engines. This procedure yields the nondimensional groups which must have the same value in both the test rig and the engine to produce similarity between the test results and the engine performance. These results guide the experimentalist in the design and selection of test equipment that properly scales quantities to actual engine conditions. They also provide a firm fundamental foundation for substantiation of previous similarity analyses which employed heuristic, physical reasoning arguments to arrive at the nondimensional groups
Searching for dark radiation at the LHC
In this work we explore the intriguing connections between searches for long-lived particles (LLPs) at the LHC and early universe cosmology. We study the non-thermal production of ultra-relativistic particles (i.e. dark radiation) in the early universe via the decay of weak-scale LLPs and show that the cosmologically interesting range ∆Neff ~ 0.01–0.1 corresponds to LLP decay lengths in the mm to cm range. These decay lengths lie at the boundary between prompt and displaced signatures at the LHC and can be comprehensively explored by combining searches for both. To illustrate this point, we consider a scenario where the LLP decays into a charged lepton and a (nearly) massless invisible particle. By reinterpreting searches for promptly decaying sleptons and for displaced leptons at both ATLAS and CMS we can then directly compare LHC exclusions with cosmological observables. We find that the CMB-S4 target value of ∆Neff = 0.06 is already excluded by current LHC searches and even smaller values can be probed for LLP masses at the electroweak scale
A meta-analysis of the international gender wage gap
Since the early seventies, hundreds of authors have calculated gender wage differentials between women and men of equal productivity. Consequently, estimates for the gender wage gap have been published for the most diverse countries at different points in time. This metastudy provides a quantitative review of this vast amount of empirical literature on gender wage discrimination as it concerns differences in methodology, data, countries and time periods. We place particular emphasis on a proper consideration of the quality of the underlying study which is done by a weighting with quality indicators. The results show that data restrictions have the biggest impact on the resulting gender wage gap. Moreover, we are able to show what effect a misspecification of the underlying wage equation-like the frequent use of potential experience-has on the calculated gender wage gap. Over time, raw wage differentials world-wide have fallen substantially; however, most of this decrease is due to an increased labor market productivity of females.Gender wage differential; meta-analysis
Fitness Uniform Optimization
In evolutionary algorithms, the fitness of a population increases with time
by mutating and recombining individuals and by a biased selection of more fit
individuals. The right selection pressure is critical in ensuring sufficient
optimization progress on the one hand and in preserving genetic diversity to be
able to escape from local optima on the other hand. Motivated by a universal
similarity relation on the individuals, we propose a new selection scheme,
which is uniform in the fitness values. It generates selection pressure toward
sparsely populated fitness regions, not necessarily toward higher fitness, as
is the case for all other selection schemes. We show analytically on a simple
example that the new selection scheme can be much more effective than standard
selection schemes. We also propose a new deletion scheme which achieves a
similar result via deletion and show how such a scheme preserves genetic
diversity more effectively than standard approaches. We compare the performance
of the new schemes to tournament selection and random deletion on an artificial
deceptive problem and a range of NP-hard problems: traveling salesman, set
covering and satisfiability.Comment: 25 double-column pages, 12 figure
- …