A large body of experimental and theoretical flutter results for hydrofoil struts were analyzed to determine significant characteristics. Flutter was found to occur in two different structural mode shapes, corresponding to a predominantly bending mode and a predominantly torsional mode, respectively. The flutter mode shape was related to the vibration mode shapes and the generalized mass ratio ...

Geometric imperfections such as radial imperfection, diamond shape, and local dimples could affect the buckling mode and load carrying capacity of axially compressed steel tubular columns. This paper experimentally investigates the effect of radial imperfection on the load carrying capacity of tubular columns. Test samples include 100 specimens with different values for diameter, length, thickn...

A nonuniform-shape photonic crystal taper integrated with a single-mode optical fiber and a photonic crystal waveguide for high-efficiency mode coupling is presented. The curvature of the tapering section is varied by the parameter alpha. For values of alpha set to 2 and 0.5, concave and convex tapers are obtained, respectively. Numerical calculations yield an average coupling efficiency greate...

It is introduced that the mass sensitivity (Sm) of an acoustic wave (AW) device with a concentrated mass can be simply determined using its mode shape function: the Sm is proportional to the square of its mode shape. By using the Sm of an AW device with a uniform mass, which is known for almost all AW devices, the Sm of an AW device with a concentrated mass at different locations can be determi...

We formulate the problem of designing the low-loss cavity for the International Linear Collider (ILC) as an electromagnetic shape optimization problem involving a Maxwell eigenvalue problem. The objective is to maximize the stored energy of a trapped mode in the end cell while maintaining a specified frequency corresponding to the accelerating mode. A continuous adjoint method is presented for ...

A compact narrowband non-degenerate dual-mode microstrip filter with square shape cuts is presented. The structure is developed by loading the conventional non-degenerate dual-mode resonator by open circuit stubs at two opposite corners. The filter bandwidth is controlled by only decreasing the higher cutoff frequency of the conventional type. With Square shape cuts, return loss is improved. A ...

We derive demand-bound functions for mixedcriticality sporadic tasks, and use these to determine EDFschedulability. Tasks have different demand-bound functions for each criticality mode. We show how to shift execution demand from highto low-criticality mode by tuning the relative deadlines. This allows us to shape the demand characteristics of each task. We propose an efficient algorithm for tu...

Minimization of power of higher order modes (HOMs) in a multicell cavity was done using derivatives of the parameter defining losses with respect to geometric parameters of the cavity cells. For the Cornell Energy Recovery Linac most dangerous are dipole modes causing beam break-up (BBU). As a start point of optimization the shape with minimal losses at the fundamental mode was taken. Further c...

In this paper mathematical formulation for buckling analysis of a column and vibrationanalysis of a beam is presented. The beam and the column is assumed to be non-uniform and cracked.Using calculus of variations, the problem is expressed as an optimization problem. A technique ofoptimization is used for analysis of buckling load. Considering the similarity between the governingequation for buc...