4,877 research outputs found
Investigation of effectiveness of various methods with different unknown variables for 3-D eddy current analysis
Get PDFComputer codes using the A-φ, A-φ-Ω, A*-0Ω-E, T-Ω, and E-Ω methods were developed. The effects of the volume ratio of the conductor region to the whole region, the shape of the conductor, and the ratio of the hole region to the conductor region on the computer storage, the CPU time, and the accuracy of the methods are investigated systematically using a few simple models. The effect of the conductivity of the conductor is also examined. The computer storage, the CPU time, and the error are found to increase with increase of the volume ratio of the conductor region to the whole region. The computer storage and the CPU time are affected by the shape of the conductor in some methods of analysis. The error of the A*-Ω(E-Ω) method is larger than that of the other methods</p
Finite-temperature properties of hard-core bosons confined on one-dimensional optical lattices
Full text linkWe present an exact study of the finite-temperature properties of hard-core
bosons (HCB's) confined on one-dimensional optical lattices. Our solution of
the HCB problem is based on the Jordan-Wigner transformation and properties of
Slater determinants. We analyze the effects of the temperature on the behavior
of the one-particle correlations, the momentum distribution function, and the
lowest natural orbitals. In addition, we compare results obtained using the
grand-canonical and canonical descriptions for systems like the ones recently
achieved experimentally. We show that even for such small systems, as small as
10 HCB's in 50 lattice sites, there are only minor differences between the
energies and momentum distributions obtained within both ensembles.Comment: RevTex file, 12 pages, 16 figures, published versio
Counterflow Extension for the F.A.S.T.-Model
Full text linkThe F.A.S.T. (Floor field and Agent based Simulation Tool) model is a
microscopic model of pedestrian dynamics, which is discrete in space and time.
It was developed in a number of more or less consecutive steps from a simple CA
model. This contribution is a summary of a study on an extension of the
F.A.S.T-model for counterflow situations. The extensions will be explained and
it will be shown that the extended F.A.S.T.-model is capable of handling
various counterflow situations and to reproduce the well known lane formation
effect.Comment: Contribution to Crowds and Cellular Automata Workshop 2008. Accepted
for publication in "Cellular Automata -- 8th International Conference on
Cellular Automata for Research and Industry, ACRI 2008, Yokohama, Japan,
September 23-26, Springer 2008, Proceedings
Two-frequency heating technique at the 18 GHz electron cyclotron resonance ion source of the National Institute of Radiological Sciences
Full text linkThe two-frequency heating technique was studied to increase the beam
intensities of highly charged ions provided by the high-voltage extraction
configuration (HEC) ion source at the National Institute of Radiological
Sciences (NIRS). The observed dependences on microwave power and frequency
suggested that this technique improved plasma stability but it required precise
frequency tuning and more microwave power than was available before 2013.
Recently, a new, high-power (1200 W) wide bandwidth (17.1-18.5 GHz)
travelling-wave-tube amplifier (TWTA) was installed. After some single tests
with klystron and TWT amplifiers the simultaneous injection of the two
microwaves has been successfully realized. The dependence of highly charged
ions (HCI) currents on the superposed microwave power was studied by changing
only the output power of one of the two amplifiers, alternatively. While
operating the klystron on its fixed 18.0 GHz, the frequency of the TWTA was
swept within its full limits (17.1-18.5 GHz), and the effect of this frequency
on the HCI-production rate was examined under several operation conditions. As
an overall result, new beam records of highly charged argon, krypton, and xenon
beams were obtained at the NIRS-HEC ion source by this high-power two-frequency
operation mode
An electro-chemo-mechanical analysis of solid oxide fuel cell considering evolution of microstructure in porous electrode using phase-field method
Get PDFFor the numerical simulation of oxygen potential distributions in Solid Oxide
Fuel Cell (SOFC), the time-evolution of the anode microstructure is reflected in the
macroscopic electrical conductivities and the amount of triple-phase boundaries. Once the
oxygen potential distributions are determined, the time-variation of the reduction-induced
strains due to nonstoichiometry of oxide materials is calculated along with the thermal strains.
These strains cause the macroscopic stresses in mutually constrained components. Thus, the
capability of the proposed method is demonstrated in characterizing the aging degradation of
the macroscopic electro-chemo-mechanical behavior of SOFC that is caused by the Nisintering
in cermet microstructures during long-period control
Comparison of various methods of analysis and finite elements in 3-D magnetic field analysis
Get PDFIn order to evaluate the most suitable method of analysis (A- phi or T- Omega method) and finite element (nodal or edge element) for a given problem, the features of each method and element have been investigated. The accuracy, computer storage, and CPU time of each method and element are compared for a 3-D nonlinear magnetostatic model and a 3-D eddy current model. The flux and eddy current densities calculated are compared with those measured. It is shown that the accuracy and the CPU time of the edge element are better than those of the nodal element. The A- phi method is better than T- Omega method for nonlinear problems from the viewpoint of convergence characteristics of nonlinear iterations.</p
Serum midkine levels are increased in patients with various types of carcinomas
Get PDFThe level of expression of midkine (MK), a heparin-binding growth factor, is increased in many types of human carcinomas. An enzyme-linked immunoassay, which utilizes a combination of rabbit and chicken antibodies revealed that serum MK level in the controls (n= 135) was 0.154 ± 0.076 (mean ± SD) ng ml–1with an apparent cut-off value as 0.5 ng ml–1. Serum MK level was significantly elevated in the cancer patients (n= 150) (P< 0.001); 87% of the patients showed levels of more than 0.5 ng ml–1. All ten types of cancer examined showed a similar profile of serum MK level. There was no or weak correlation between C-reactive protein level, a marker of inflammation, and serum MK level. Furthermore, in case of gastric carcinoma and lung carcinoma, patients with stage I carcinoma already showed elevated serum MK levels. The present results indicated that serum MK could serve as a general tumour marker with a good potential for clinical application. © 2000 Cancer Research Campaig
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