In this paper we prove an existence result for Kahler metrics with constant Hermitian scalar curvature (CHSC) on ruled manifolds. This is part of a research program suggested by Simon Donaldson, [6], which is closely related to Tian's work, [16], and Yau's conjecture on Einstein-Kahler metrics. The main result (Theorem A) of this paper has been announced in [9], where a partial proof has been given. We recall the statement (and assumptions) of Theorem A as follows:[X] Assume that (M : %) is an m-dimensional compact Kahler manifold with constant Hermitian scalar curvature and n : E -> M is a simple holomorphic vector bundle of rank n over M with an Einstein-Hermitian metric HE-Let A denote the Einstein-Hermitian connection on E induced by HE-Let F(E) denote the projectivization of E over M. Then ¥(E) is an (m + n -l)-dimensional complex manifold. Let L be the universal line bundle over ¥(E). Then the Einstein-Hermitian metric HE induces a Hermitian metric HE* on L* over ¥(E). Thus there is a representative of the Euler class e (L*) of L* on ¥(E) induced by the Hermitian metric HE*-Note that the representative (^FH L ,) of e(L*) on F(E) induces the Fubini-Study metric on each fiber of n : ¥(E) -> M. Thus, for each k G N large enough,

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We consider an optimization problem on the maximal magnitude of angular acceleration of the output-links of a commercially available center-driven linkage system (CDLS) for vehicle wipers on windshield. The purpose of this optimization is to improve the steadiness of a linkage system without weakening its normal function. Thus this optimization problem is considered under the assumptions that the frame of the fixed links of linkage system is unchanged and that the input-link rotates at the same constant angular speed with its length unchanged. To meet the usual requirements for vehicle wipers on windshield, this optimization problem must be solved subject to 10 specific constraints. We expect that optimizing the maximal magnitude of angular acceleration of the output-links of a linkage system would also be helpful for reducing the amplitudes of sound waves of wiper noise. We establish the motion model of CDLS and then justify this model with ADAMS. We use a “Differential Evolution” type method to search for the minimum of an objective function subject to 10 constraints for this optimization problem. Our optimization computation shows that the maximal magnitude of angular acceleration of both output-links of this linkage system can be reduced by more than 10%.