Sökresultat

Filtyp

Din sökning på "*" gav 567319 sökträffar

No title

Convincing evidence of a nonvanishing string tension in the continuum limit of compact three-dimensional U(1) gauge theory is presented. It is based on Monte Carlo measurements of Wilson loops on a 323 lattice at =2.0 and 2.2. The observed string tensions at these couplings are consistent with the Polyakov theory. Also, a very clean signal of a string vibrational contribution to the potential is o

No title

Purpose: To use first-pass perfusion and delayed-enhanced (DE) magnetic resonance (MR) imaging for the detection of the early effects of coronary microembolization on myocardial perfusion and viability. Materials and Methods: Approval was obtained from the institutional committee on animal research. A hybrid x-ray and MR imaging system was used to guide the endovascular catheter and quantify the l

No title

The deconfinement temperature Tc of (2+1)-dimensional SU(2) gauge theory is measured on lattice sizes varying from 2 × 202 to 6 × 602 and with β in the rate 3-9. Approximative scaling is found for β > 6.5 and Tc/√σ = 0.94 ± 0.03 is obtained. This value is in excellent agreement with (3/π) 1 2, as predicted from the breakdown of SU(2) confinement in terms of an effective scalar string theory.

No title

Numerical evidence for a nonvanishing 0++ glueball mass in three-dimensional SU(2) is presented. By using a long-distance correlation Monte Carlo method we obtain m0++ = (4.7±1.2)√σ in the β-range 4.0-6.5. The measurements are consistent with 1/β-scaling. The relevance of this result for SU(2) in four dimensions at finite temperature is briefly discussed.

No title

The decay from the 23+ state at about 2-MeV excitation in the nuclei Ba140, Ce142, and Nd144, with 84 neutrons, is shown to be consistent with its identification as the lowest state of mixed symmetry in the U(5) limit of the neutron-proton version of the interacting-boson model.

No title

Gas turbines are broadly used in aerospace and marine propulsion and power production etc.Investigation of heat transfer in gas turbines is a long-lasting and still an active subject ofresearch due to its tremendous importance. Thermal efficiency, durability and fatigue lifetimeof a gas turbine greatly rely on the heat transfer characteristics of gas turbine components.According to the first law o

No title

A fully integrated instrument for cereal grain quality assessment is presented. Color video images of grains fed onto a belt are digitized. These images are then segmented into kernel entities, which are subject to the analysis. The number of degrees of freedom for each such object is decreased to a suitable level for Artificial Neural Network (ANN) processing. Feed- forward ANN's with one hidden

No title

A package written in C for identifying variable dependencies in tables of data is presented. The key ingredient is the δ-test, which establishes dependency structures by exploiting the properties of continuous functions using conditional probabilities formed out of the data. The method estimates most relevant variables, embedding dimensions and noise levels. The program, which is self-contained, a

No title

A brief review is given for the use of feed-back artificial neural networks (ANN) to obtain good approximate solutions to combinatorial optimization problems. The key element is the mean field approximation (MFT), which differs from conventional methods and "feels" its ways towards good solutions rather than fully or partly exploring different possible solutions. The methodology, which is illustra

No title

We present a high statistics Monte Carlo investigation of a 3-dimensional Z 3 symmetric model, which is related to SU(3) pure gauge theory at finite temperature. From the finite size scaling behaviour of bulk properties and the existence of metastable states, we conclude that this model exhibits a first-order pha

No title

A feed-forward neural network method is developed for reconstructing the invariant mass of hadronic jets appearing in a calorimeter. The approach is illustrated in W→qq, where W-bosons are produced in pp reactions at SPS collider energies. The neural network method yields results that are superior to conventional methods. This neural network application differs from the classification ones in the

No title

The authors describe an approach to particle tracking based on deformable templates. Hough transforms are used to give initial conditions for the templates which then converge using a deterministic annealing algorithm. This template approach is closely related to the elastic net algorithm. The authors demonstrate successful results on both simulated and real data. The authors also show how the Hou

No title

We present a novel, versatile optoelectronic neural network architecture for implementing supervised learning algorithms in photorefractive materials. The system is based on spatial multiplexing rather than the more commonly used angular multiplexing of the interconnect gratings. This simple, single-crystal architecture implements a variety of multilayer supervised learning algorithms including me

No title

Static anatomical and real-time dynamic magnetic resonance imaging (RT-MRI) of the upper airway is a valuable method for studying speech production in research and clinical settings. The test-retest repeatability of quantitative imaging biomarkers is an important parameter, since it limits the effect sizes and intragroup differences that can be studied. Therefore, this study aims to present a fram

No title

We explore the possibilities of using the complex Langevin equation to Monte Carlo generate configurations of gauge theories with static charges present in the action. Successful results are obtained for systems that possess nontrivial saddle-point (classical) solutions. For that reason the algorithm works impressively for two-dimensional U(1) in the entire β-range whereas for three- and four-dime

No title

From the 1880s until the ban of this practice in the 1970s, German vacationers built sandcastles, some of which were artfully decorated and awarded prizes in competitions by the spa administrations. Research regards this as a manifestation of a ‘typical German’ national character. The article counters this approach with an interpretation that understands sandcastles as metaphors for typical charac

No title

By using the Langevin equation with complex action it is possible to generate (complex) configurations in the charged sector of gauge theories. We test the algorithm in the case of two-dimensional U(1) gauge theory and are able to measure the string tension with great precision and modest use of computer time for a separation of the charged particles where a conventional Wilson loop would have a v