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The modern missile has low uncertain and wide range vibration frequency. The conventional notch filter with the fixed notch frequency is less effective than that of the adaptive notch filter (ANF) in vibration suppression for the time-varying vibration frequency.

To overcome the drawback, a novel method is based on frequency estimators made by interpolation of three discrete Fourier transform (DFT) spectral lines. The modified frequency estimators based on the interpolation of three DFT spectral lines are presented to identify and track the vibration frequency. Then the notch frequencies of multiple ANFs are real-timely tuned according to estimators.

Finally, taking the second-order flexible missile as an example, the performance of the proposed method is verified. The verified simulation results show that multiple ANFs are effective in vibration suppression.

Cascading multiple ANFs to achieve multi-order vibration suppression is more efficient and feasible than conventional fixed-parameter notch filtering.

The frequency estimation method based on three DFT spectral lines proposed in this paper can effectively identify and track signals in the noise environment. Compared with conventional methods, the method pretended in this paper has high identification accuracy and a stronger ability to track signals. It can meet the fast frequency identification requirements of the actual flexible missile.

To study the effect of rocket mass and an intermediate mass on the critical flutter load of a free‐free beam (missile‐like structure).

A finite element model of beam considering shear deformation and rotary inertia, based on Hamilton's principle applied to non‐conservative system.

Smaller geometric dimensions of the end rocket assist in the stability. Optimum positioning of the intermediate mass leads to stability.

The stability of free‐free missile structures can be better understood.

Sheds new light on the effect of rocket mass and an intermediate mass on the critical flutter load of a free‐free beam.

The equation of motion of a free‐free moving column with a prescribed axial acceleration is formulated based on Hamilton’s principle and the assumed mode method. The slender column is used as a simple model for a missile or a launched vehicle. The column is under the action of aerodynamic forces which are modelled as axial external loads at the ends of the column. The effects of axial sinusoidal perturbations in respect of axial acceleration and the external loads are then examined using Bolotin’s method. The respective regions of instability are determined by converting the resulting equations of boundary frequencies to the standard form of a generalized eigenvalue problem. Instability regions for various combinations of external loads and axial acceleration of the column are presented.

MODERN air travel has produced a breed of passenger whose interest in the aircraft conveying them to their destinations are blase. To most of today's passensers, cabin comfort, decor, the offerings from the galley and bar are the only distinguishing features of the aircraft travelled in. Little interest is shown in the aircraft's technical features, its power‐plants or its advanced avionics. If asked where the aircraft fuel is stored a passenger may vaguely answer: “In the wing — I think.”

The equation of motion of a beam on multiple supports, subject to prescribed time‐dependent conservative axial loads, is formulated based on Hamilton’s principle and the assumed mode method. The effects of sinusoidal perturbations in respect of the axial loads are then examined using Bolotin’s method. The respective regions of instability are determined by converting the resulting equations of boundary frequencies into the standard form of a generalized eigenvalue problem. Instability regions are presented for various combinations of support configuration, average value and amplitude of the sinusoidal perturbations of the axial loads.

Briefly reviews previous literature by the author before presenting an original 12 step system integration protocol designed to ensure the success of companies or countries in their efforts to develop and market new products. Looks at the issues from different strategic levels such as corporate, international, military and economic. Presents 31 case studies, including the success of Japan in microchips to the failure of Xerox to sell its invention of the Alto personal computer 3 years before Apple: from the success in DNA and Superconductor research to the success of Sunbeam in inventing and marketing food processors: and from the daring invention and production of atomic energy for survival to the successes of sewing machine inventor Howe in co‐operating on patents to compete in markets. Includes 306 questions and answers in order to qualify concepts introduced.

The background of missile costs is discussed. Missiles are new and very costly. Developments in this field have been subjected to political vicissitudes which have often upset long‐term developments. Missile technology is on the frontier of science and there is no background of knowledge to draw on; much basic and expensive research is required. Missile engineering models are complex in detail and assembly, and therefore costly, and constant change occurs while making and testing the model. The complexity and functional requirements of missile parts are running a parallel race with the machines and processes being developed to fabricate the materials required. The usually small runs required in missile production again add to costs. Imposed on all these activities is the requirement that reliability of near 100 per cent is needed and in no case can reliability be allowed to be secondary to cost. The inflight life and shelf conditions for a missile are usually fairly well established and 100 per cent reliability for a short operating life with a long shelf life are the real requirements. There is a considerable tendency to overdesign for reliability. Some costly features of design such as finest finish, closest tolerances and highest strength are carried over by habit from aircraft design and are not always required in missiles. Having examined some causes of high costs, a programme for cost reduction is set out. Costs can be reduced by: (i) earlier freezing of designs making changes only in groups of several changes at wider intervals, (ii) making a more realistic approach to reliability designs, (iii) selecting tolerances in a more analytical manner according to individual needs, (iv) selecting materials on the basis of actual design requirements instead of using the very best materials available even when the short life makes them unnecessary, (v) avoiding tool‐room methods in production engineering, (vi) setting work standards on as many operations as possible and enforcing them to the greatest degree possible, (vii) selecting the best type of workers to make the transition from development models to production missiles as smooth as possible, and (viii) setting up rigid systems and parts designation procedures for handling production parts. Finally, methods of organizing research and development and production for bridging the gap between engineering design and production are proposed.

PHOTOGRAPHIC details of various aircraft and missiles recently released in conjunction with the Soviet air show at Tushino Airport on July 9, 1961, has provided a basis for the start of an evaluation of Soviet air‐to‐air rocket weapons. These pictorial data, coupled with Russian textbooks, as well as evidence of Soviet interest in the guided‐missile work of the Western Powers, indicated by the material that has been translated from English into Russian,1 has led to this brief evaluation of their work in this field.

THE experimental determination of the moment of inertia of a body is frequently required to confirm a calculated value or to eliminate the tedious work involved in the calculation. This is normally done by integrating the body into a vibrating system, such as a pendulum.