A Chain of Dark Clouds in Projection Against the Galactic Center

In the J, H, and Ks bands survey of the the Galactic Center region over an area of 2deg x 5deg, we have found many dark clouds, among which a distinguished chain of dark clouds can be identified with a quiescent CO cloud. The distances of the clouds is estimated to be 3.2-4.2 kpc, corresponding to the Norma arm by our new method to determine distance to dark clouds using the cumulative number of stars against J-Ks colors. Adopting these estimated distances, the size is about 70 pc in length and the total mass of the cloud is 6x10^4 M_solar. Three compact HII regions harbor in the cloud, indicating that star forming activities are going on at the cores of the quiescent CO cloud on the spiral arm.Comment: 13 pages, 7 figures, accepted for publication in PAS

MECHANICAL BEHAVIOR OF ANTI-SYMMETRICALLY LAMINATED COMPOSITE BLADES

ABSTRACT Anti-symmetrically laminated composites have coupling effects between tensile stress and twisting deformation, and are very attractive as fan blade materials of aircraft engines. Blades fabricated by anti-symmetrically laminated composites can automatically adjust the stagger angle to better aerodynamic conditions with change of axial force or rotational speed owing to the coupling effects. Thus, the anti-symmetrically laminated composite blades are expected to improve aerodynamic efficiency and the stability of aircraft engines. In this paper, the mechanical behavior of antisymmetrically laminated composite blades is evaluated by spin tests and finite element analyses