Body surface isochrone mapping was performed in 36 normal subjects and in 85 patients with previous myocardial infarction. Eighty-seven unipolar electrocardiograms distributed over the anterior chest and the back were recorded simultaneously. For each lead, activation time was measured as the time from the onset of QRS to the peak of the R wave. The lead points where R waves were not observed w...

We present interferometric observations of seven main-sequence and three giant stars with spectral types from B2 to F6 using the Precision Astronomical Visible Observations beam combiner at the Center for High Angular Resolution Astronomy array. We have directly determined the angular diameters for these objects with an average precision of 2.3 per cent. We have also computed bolometric fluxes ...

We first presented an isochrone database that can be widely used for stellar population synthesis studies and color magnitude diagram (CMD) fittings. The database consists of the isochrones of both single and binary stellar populations (SSPs and BSPs). The ranges for the age and metallicity of populations are 0–15 Gyr and 0.0001–0.03, respectively. All data are available for populations with tw...

An extensive grid of metal-rich isochrones utilizing the latest available input physics has been calculated for comparison with the old, metal-rich open cluster NGC6791. The isochrones have been simultaneously fit to BV and VI color magnitude diagrams, with the same composition, reddening and distance modulus required for both colors. Our best fitting isochrone assumes [Fe/H] = +0.4, scaled sol...

We revisit in this note the H\'enon's isochrone problem. By using standard Abel inversion technique for one-dimensional motion, we recover a simple way parabolae and get all central potentials under mild smoothness assumptions on potential function. Our approach also allows us to conclude that isochronous radial periods with explicit energy dependence are necessarily Keplerian, i.e., $T^{2}\pro...

We study the bifurcation of local critical periods in the differential system { ẋ = −y +Bxn−1y, ẏ = x+Dx + Fxn−2y2, where B,D,F ∈ R and n > 3 is a fixed natural number. Here by “local” we mean in a neighbourhood of the center at the origin. For n even we show that at most two local critical periods bifurcate from a weak center of finite order or from the linear isochrone, and at most one local ...

time–area method is one of the most widely applied techniques of watershed routing, and can be potentially used as a distributed model. in this paper, a fundamental flaw in the arrangement of subareas in the original time-area histogram is identified for one-dimensional flow. this is conducted on the basis of comparing time-area hydrograph with that of the kinematic wave theorem. accordingly, a...

Hipparcos parallaxes and proper motions have made it possible to construct Hertzsprung-Russell (H-R) diagrams of nearby clusters with unprecedented accuracy. The standard deviation of high-fidelity, nonbinary, nonvariable stars about a model stellar evolution isochrone in the Hyades cluster is about 0.04 mag. We use this deviation to estimate an upper limit on the scatter in metallicities in st...