The morphology of the ǫ Eridani dust ring is reproduced by a numerical simulation of dust particles captured into the 5:3 and 3:2 exterior mean-motion resonances with a 0.3 eccentricity 10 solar mass planet at periastron at a semi-major axis of 40 AU. The morphology will differ when the planet is at apastron, in about 140 years. Moderate eccentricity planets in outer extra-solar systems will ca...

We have measured the positions of H2O masers in Sgr B2, a massive star forming region in the Galactic center, relative to an extragalactic radio source with the Very Long Baseline Array. The positions measured at 12 epochs over a time span of one year yield the trigonometric parallax of Sgr B2 and hence a distance to the Galactic center of R0 = 7.9 +0.8 −0.7 kpc. The proper motion of Sgr B2 rel...

Cones show a differential sensitivity to light coming from different portions of the pupil, typically being most sensitive to light from the center of the pupil. We measured the directional properties of the cones across the central 6 deg of the retina, using an optical imaging technique. We find that the cones in the center of the fovea have the broadest tuning. The width of the angular tuning...

We have measured the positions of H2O masers in Sgr B2, a massive star forming region in the Galactic center, relative to an extragalactic radio source with the Very Long Baseline Array. The positions measured at 12 epochs over a time span of one year yield the trigonometric parallax of Sgr B2 and hence a distance to the Galactic center, R0, of R0 = 7.9 +0.8 −0.7 kpc. The proper motion of Sgr B...

The minimum spanning tree clustering algorithm is capable of detecting clusters with irregular boundaries. In this paper we propose a novel minimum spanning tree based clustering algorithm. The algorithm produces k clusters with center and guaranteed intra-cluster similarity. The algorithm uses divisive approach to produce k number of clusters. The center points are considered as representative...

Let D = (V,E) be a digraph and u, v ∈ V. The metric maximum distance is defined by md(u,v) max {d⃗(u,v), d⃗(v,u)}, where d⃗(u,v) denote the length of shortest directed u − path in D. m-eccentricity vertex mecc(v) {md(v,u) : V(D)}. m-center mC(D) strongly connected consists all vertices with minimum m-eccentricity, m-periphery mPer(D) relationship between two digraphs their lexicographic product st...

By theoretically analyzing dynamic behavior of the crankshaft, the rolling piston and the blade inrolling-piston rotary compressors, constraint forces and sliding speed at each pair of movable machine elements were obtained, and unbalanced inertia forces and compressor vibrations were evaluated. It was concluded that theoretical results have a goodagreement with experimental ones. Moreover, it ...

Resent observations and theoretical interpretations suggest that IMBHs (intermediate-mass black hole) are formed in the centers of young and compact star clusters born close to the center of their parent galaxy. Such a star cluster would sink toward the center of the galaxy, and at the same time stars are stripped out of the cluster by the tidal field of the parent galaxy. We investigated the o...

Characterization of transiting planets with transit timing variations (TTVs) requires understanding how to translate the observed TTVs into masses and orbital elements of the planets. This can be challenging in multi-planet transiting systems, but fortunately these systems tend to be nearly planeparallel and low eccentricity. Here we present a novel derivation of analytic formulae for TTVs that...

Mean motion resonances are important in the analysis and understanding of dynamics planetary systems. While perturbative approaches have been dominant many previous studies, recent non-perturbative revealed novel properties low eccentricity regime for interior mean Jupiter fundamental model circular planar restricted three body model. Here we extend investigation to exterior (up about 0.1) pert...