a new base isolation method for reducing the destructive effect of earthquake is proposed in this method mushroom shaped basements are used under structures as base isolation. these basements have spherical surface and are located on foundations. basements have pinned arms that are connected. when the length of the arm is less then the radius of spherical surface, the action of them is similar ...

Throughout the years, various classifications have evolved for the diagnosis of vascular anomalies. However, it remains difficult to classify a number of such lesions. Because all hemangiomas were previously considered to involute, if a lesion with imaging and clinical characteristics of hemangioma does not involute, then there is no subclass in which to classify such a lesion, as reported in o...

Main Outcome Measures: Investigators documented the location, extent, and severity of ROP during serial retinal examinations. The onset of the ROP’s involution was determined from a review of these data, applying a set of predetermined criteria. Results: Acute-phase ROP began to involute at a mean of 38.6 weeks postmenstrual age. In 90% of patients, the ROP began to involute before 44 weeks of ...

In this paper, novel non-involute cylindrical gears are designed based on a curved path of contact. Firstly, parabolic curve is predesigned as the contact gears. Then, tooth profiles calculated using differential geometry and spatial meshing theory. Secondly, three-dimensional models established according to machining simulation. Thirdly, simulation model (including misalignment error longitudi...