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A method has been developed for computing aerodynamic loads on slender missiles with complicated cross‐sections. This method has been applied to the prediction of loads for missiles with folding wings. Comparison of theoretical calculations with supersonic wind‐tunnel measurements indicates that the method should provide satisfactory first estimates of the aerodynamic properties of missiles with folding wings. A series of design charts is presented to allow rapid estimation of lift, folding moment and span loading for a wide variety of folding‐wing configurations.

The purpose of this paper is to examine extreme value charts and analyse means based on half logistic distribution.

Variable control charts with subgroup observations based on the extreme values at each subgroup are constructed without specially going to any subgroup statistic. The control chart constants depend on the probability model of the extreme order statistic of each subgroup and the size of the subgroup. Accordingly the proposed chart is normal as extreme value chart. As a by‐product the technique of analysis of means for a skewed population is exemplated through half logistic distribution and extreme value control charts. The results are illustrated by examples on live data.

H.L.D is found to be better test for the data of the three examples, ANOM gave a larger (complete) homogeneity of data than those of Ott.

Supposing arithmetic means of k subgroups of size “n” each drawn from a half logistic model. If these subgroup means are used to develop control charts to assess whether the population from which these subgroups are drawn is operating with admissible quality variations. Depending on the basic population model, we may use the control chart constants developed by the authors or the popular Shewart constants given in any SQC text book. Generally the authors say that the process is in control if all the subgroup means fall within the control limits. Otherwise it is said that the process lacks control.

Half logistic distribution is a better model, exhibiting significant linear relation between sample and population quantiles.

‘Shear‐constraints’ can be used to produce efficient Mindlin/Reissner or ‘discrete Kirchhoff’ bending elements. The paper shows that ‘selective shear‐constraints’ can be used to produce an effective formulation for folded‐plated structures.

The purpose of this study was to develop a new folding method for modeling complicated folded fabric with surfaces of revolution.

Irregular wrinkles and mesh distortions easily appear in the fold modeling of a complex curved surface. Aimed at this key technical problem, the segmentation mapping folding method (SMFM) is proposed in this paper. First, high-precision flattened planes were obtained by using segmentation mapping techniques. Second, the segmented planes were transformed into a folded and continuous geometric model by using matrix transformations. Finally, initial stress was used to modify the geometric folding errors, which ensured agreement with the inflated flexible fabric’s geometry and the original design.

Compared with the traditional folding method, SMFM has the advantages of good finite-element mesh quality, large radial compression rate, regular folds, etc. The surface area error and the volume error of the inflated single torus established by SMFM were only 1.2 per cent, showing that SMFM has high modeling accuracy. The numerical results of an inflatable re-entry vehicle are presented to demonstrate the reliability, feasibility and applicability of SMFM. Moreover, the stress modification reduced the problems of stress concentration and mesh distortions, improving the accuracy and stability of the numerical calculations.

In this paper, for the first time, a folding method for modeling complicated folded fabric is proposed. This methodology can be used to model the multidimensional compression and regular folds of complex surfaces of revolution that cannot be flattened and to improve the accuracy and stability of the numerical calculations.

A BODY known as the Local Government Personnel and Management Services Group has been moved to issue a short paper commenting on the Bains Report issued by the Bains Committee to which the Group submitted evidence.

The purpose of this paper is to build a new deployable antenna with folded scissors ribs and to evaluate the reasonable characteristics of this new structure.

Based on the TerrStar-1 satellite, virtual design and shapes forming are considered in this paper with the structure design of the new antenna. Considering the relaxation units in net surface, form-finding evaluation is used to build mathematical model and operate the optimization algorithm so that the design of the new antenna with folded scissors ribs is achieved. Simulations are carried out to verify the antenna proposed.

It is found that the antenna with folded scissors ribs can be developed smoothly in the space.

The proposed the antenna with folded scissors ribs can be considered as a fall-back alternative for large antenna, with a diameter of over 10 m in the space, or is seen as another option for the system with a simple rigid structure.

Different from traditional antenna, it provides a valuable reference for the further research of large deployable antenna in space. The antenna in this paper is able to develop more than 30 m of diameter. Meanwhile, the surface density and the natural frequency and the root-mean-square error in surface are superior to those of the traditional antenna.

IT IS an absurd paradox that whereas some firms have the legend ‘Work Study’ on the door, they set their rates along ratefixing lines. With wages soaring and little to show by way of increased output, it is important to keep inflationary rates at bay. ‘Rates’ are intended to imply rates of output irrespective of the mode in which they are expressed. Standard minutes are intended to be earned and their establishment should, therefore, still be in accordance with the equitable principles of a good incentive system. And while it is quite understandable that some practitioners should tend to play safe by ‘loading’ the rate in order to avoid any subsequent shop floor conflict in regard to bonus earnings, the situation should never be allowed to degenerate into one which high bonus earnings—without reference to standards— are to be regarded as a condition precedent to greater effort.

Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.

Allyn Young′s lectures, as recorded by the young Nicholas Kaldor, survey the historical roots of the subject from Aristotle through to the modern neo‐classical writers. The focus throughout is on the conditions making for economic progress, with stress on the institutional developments that extend and are extended by the size of the market. Organisational changes that promote the division of labour and specialisation within and between firms and industries, and which promote competition and mobility, are seen as the vital factors in growth. In the absence of new markets, inventions as such play only a minor role. The economic system is an inter‐related whole, or a living “organon”. It is from this perspective that micro‐economic relations are analysed, and this helps expose certain fallacies of composition associated with the marginal productivity theory of production and distribution. Factors are paid not because they are productive but because they are scarce. Likewise he shows why Marshallian supply and demand schedules, based on the “one thing at a time” approach, cannot adequately describe the dynamic growth properties of the system. Supply and demand cannot be simply integrated to arrive at a picture of the whole economy. These notes are complemented by eleven articles in the Encyclopaedia Britannica which were published shortly after Young′s sudden death in 1929.

The purpose of this paper is to implement the six sigma (SS) strategy in a bag sector under actual operating circumstances based on defining-measure-analyze-improve and control (DMAIC). During the project, several statistical tools and methods have been used efficiently to create inferences. Thus, to measure and enhance system efficiency, the author calculate reliability, availability and maintainability (RAM) indices. Based on this research, the author show how the SS method and RAM analysis are very helpful in determining maintenance intervals, as well as in planning and organizing the appropriate maintenance strategy.

This study introduces the step-by-step application of the DMAIC methodology for the identification and reduction of bag production line downtime and examines the present operations management. Thus, statistical techniques are used to analyze the failure and repair database. Pareto analysis, histograms and descriptive statistics at the machine and line-level of the historical data were conducted. Trend and serial correlation testing validated the hypothesis of independence and identical distribution of database was performed. In addition, with their best fit allocation, the RAM of both the bag production line and its machines was estimated at separate mission times.

The main goals of the applied method are to understand the nature of the downtime patterns and to accurately and quantitatively estimate the RAM characteristics of the bag production system. The assessment defines the production line's critical points, requiring further enhancement through an efficient maintenance approach. Therefore, by improving plant efficiency and safety, the author can decrease unplanned downtime and equipment failures.

This research is expected to serve as an attempt to conduct SS DMAIC methodology through RAM assessment and its impact on system efficiency under actual circumstances. The benefit of the methodology is that the manufacturing process is continuously monitored by suitable indicators, the use of which leads to a continuous improvement cycle.