China
Africa
Explore chapters and articles related to this topic
The Geoid and Its Steam and Stress Fields
Published in Petr Vaníček, Nikolaos T. Christou, GEOID and Its GEOPHYSICAL INTERPRETATIONS, 2020
where N, M are the radii of curvature along the prime normal section and the meridian section of the normal (ellipsoidal) equipotential surface, respectively. For normal latitudes ϕ, the relevant metric of Equation 16, for the normal equipotential surface, is given by () Gϕ=[N2cos2ϕ00M2]
Chapter 2
Published in Pearson Frederick, Map Projections:, 2018
We begin the derivation for the curvature of a surface with a consideration of normal sections through the surface. A normal section implies that the normal to the parametric curve and the surface coincide. We start with the normal at an arbitrary point. For the parametric curve, take the dot product of n^ with Equation 6. () n^⋅dt^ds=−kn^⋅n^=−k
Disk Mill Gear Cutters
Published in Stephen P. Radzevich, Gear Cutting Tools, 2017
Ultimately, the clearance surface Cs is intersected by the plane ns – ns that is orthogonal to the surface Cs. In this way, the normal section of the clearance surface Cs is constructed. In Figure 7.9, point a of the normal section of the clearance surface is denoted by acsn. This projection of point a is within the plane of projections π5. The axis of projections π2/π5 is parallel to the to the normal section ns – ns.
Local contact characteristics of threaded surfaces in a planetary roller screw mechanism
Published in Mechanics Based Design of Structures and Machines, 2020
Shangjun Ma, Linping Wu, Geng Liu, Xiaojun Fu
Based on the differential geometry theory (Ciarlet and Li 2007), for an arbitrary point on surface represents a direction of the surface at point A. The plane through the normal () of the surface at this point and in the direction is defined as a normal section. In addition, a normal section intersects surface and produces another curve, which is defined as the normal curve at point A on surface along direction We assume that the curvature of the normal curve at point A is the normal curvature i.e., To ensure that points toward the outer normal direction of the threaded surface, for the upper threaded surfaces of the screw, roller and nut and respectively, the corresponding is “” For the lower threaded surfaces and the corresponding is “”