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The article presents information on the program of the Seventh Annual Meeting of the Operations Research Society of America held in Washington, D.C. in 1959. There were many papers presented during the meeting. A. R. Marks presented his paper which discusses the testing of alternate work schedules and procedures for large-scale job-shop operations. Other topics discussed at the meeting include integrated materials management simulation, concepts in decision making, and productivity measurement in engineering design.

A methodology other than that used for research may be more appropriate for designing and engineering projects. This paper compares the purposes and methodologies of research and of designing, and concludes that while their purposes are different, their current methodologies are the same. The research or scientific methodology--with analysis as its hallmark--is shown to restrict the effectiveness of a design solution. To achieve an effective design solution, a methodology distinctly different from the research methodology is required. This paper reports on research which attempted to delineate the actual strategies used by outstanding professionals in various fields. It was found that such experts, although in different fields, have strong similarities in the steps of the strategy each used. The applications of an empirical ten-step design strategy with function determination and ideal systems development as hallmarks have shown much better results than conventional strategies based on the research methodology. Additional research is suggested to verify these early conclusions and to make the stated design strategy more effective. [ABSTRACT FROM AUTHOR]

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Every scientific study has its own unique case history. Unfortunately, most scientific papers present a greatly distorted and static image of the true history and sociology of a research project. This paper represents an attempt to report on selected aspects of the actual growth and development of a simulation project, especially as that process affected the development of a novel method for validating simulation models. The paper also represents a philosophical analysis of the concept of simulation, especially as that analysis formed an integral part of the study's development. One of the paper's main theses is that the teleology or purpose behind the construction of a simulation model is an ever present task-master guiding and influencing all the phases of a model's construction and validation. A general thesis is that a researcher's philosophy of science is as characteristic of him (i.e., his psychology) as it is of the phenomena he typically studies. The implications of these theses are illustrated in terms of the simulation of the engineering design behavior of a practicing mechanical engineer. [ABSTRACT FROM AUTHOR]

In this part of the paper, a method is given for allocating least-cost component tolerances to engineering designs whose functional requirements lead to systems of simultaneous tolerance equations, having one or more component tolerances occurring in more than one tolerance equation. These least-cost tolerances are obtained by minimising the total cost of achieving them, using the method of Lagrange's undetermined multipliers. Methods of solving the resulting non-linear equations in Lagrange's multipliers are given. A notation for the treatment of simultaneous tolerance equations is developed. The procedure is illustrated by examples. [ABSTRACT FROM AUTHOR]

There is evidence to support the view that little analysis is used in the design of control systems for sequential machines. This paper outlines a design technique for such machines, taking a specific sequence as an illustration. The techniques used for the simplification of Boolean functions are included in an abbreviated form. [ABSTRACT FROM AUTHOR]

In connection with other work to develop decision making aids for use in engineering design it appeared that the technique of AIDA might be relevant to the production engineering problem of selecting satisfactory tooling arrangements for multi-station machine tools performing many different operations on the same component. This paper describes an experiment in which this technique was taught to two engineers and used by them as part of their normal programme of work. It is suggested that the technique is of most value in this connection when a number of people need to be involved in decisions, and for training. [ABSTRACT FROM AUTHOR]

The principle and basic design of a fast machine for the determination of wool and vegetable-matter components in scoured wool are described. The machine is a development of that used in Harker's method for the separation of wool and vegetable matter by reducing the material to a finely divided state and utilizing the different densities of wool and vegetable matter to separate them by flotation. However, in contrast to Harker's method, thermal convection and density gradients are not used; the machine embodies a special centrifuge, in which the separating liquid is controlled at a density of 1.335 ±0.002 g/ml. The problem arising from the presence of low-density vegetable-matter components is discussed, and the means of treating these components to enable separation to proceed are described. The quality of separation is of a high order, and separations can be made in a few minutes. [ABSTRACT FROM AUTHOR]

It is shown that the modular design problem minimize Σ i=1 i=m Yi Σ j=1 j=n Zj, subject to Yi Zj ≧ rij > 0,can be transformed into a problem of minimizing a separable convex function subject to linear equality constraints and nonnegativities. This transformation is effected by using a generalized inverse of the constraint matrix. Moreover the nature of the functional and the constraints of the separable problem are such that a good starting point for its solution can be obtained by solving a particular transportation problem. Several possible methods for solving the separable problem are discussed, and the results of our computational experience with these methods are given. It is also shown that the modular design problem can be viewed as a special case of a large class of general engineering design problems that have been discussed in the literature. [ABSTRACT FROM AUTHOR]i Zj > 0,can be transformed into a problem of minimizing a separable convex function subject to linear equality constraints and nonnegativities. This transformation is effected by using a generalized inverse of the constraint matrix. Moreover the nature of the functional and the constraints of the separable problem are such that a good starting point for its solution can be obtained by solving a particular transportation problem. Several possible methods for solving the separable problem are discussed, and the results of our computational experience with these methods are given. It is also shown that the modular design problem can be viewed as a special case of a large class of general engineering design problems that have been discussed in the literature. [ABSTRACT FROM AUTHOR]

The article presents a letter to the editor about the concept of designing ideal systems and models.

The article focuses on the engineering factors to be considered for the construction of the dam proposed by the North American Water and Power Alliance. It states that the possibility to construct the project starts through various planning processes. These include an assessment of the potential uses of water for the future so that a continental water scheme could be devised. Despite the probable construction of the project, it claims that the proposal does not appear to be a good solution from an engineering perspective. It further enumerates some of the primary engineering weaknesses of the project including its infinite structures and large artificial reservoirs.

Accurate estimation of required effort for software development plays an important role in the success of the software project. This is always a challenging issue due to the intangible nature of the software project. Therefore, a large category of researches have been performed to develop accurate tools to estimate the required efforts for software development. According to the presented papers in related works, the adoption of methods to identify the types of relationship between software project features and features affecting the required effort for software development have a significant impact on effort estimation accuracy increment. In addition, the effectiveness of various features on the software development effort estimation is different. So, the feature effectiveness determination is advantageous in increasing the effort estimation accuracy. This paper presents a new model consisting of sub-models for project features analyzing and it uses a new and accurate heuristic algorithm called Atom Search Optimization (ASO) Algorithm to configure tools and data modeling methods. The presented model in this article is designed in multiple layers and the sub-models are organized in separate layers. The organizations of sub-models are in such a way to increase performance of other layers and ultimately increase the final estimate accuracy. In accuracy evaluation of the proposed model, 3 data sets from real projects are used and the comparisons of the results with different methods are presented. Based on the results, the proposed model leads to significant improvement of final effort estimation accuracy.

In this paper, the Smoothed Particle Hydrodynamics (SPH) method with dynamic boundary condition has been used to simulate 3D Fluid flow in the centrifugal pump. Severe fluctuations in the field of pressure and velocity is one of the major problems in this method. In this paper, the fluctuations have been corrected using Delta and Shift algorithms. The simulation was numerically performed with real fluid viscosity (laminar and turbulence). Validation of this method indicated that in the case of real fluid viscosity, the Delta and Shift algorithms should be used simultaneously to obtain good agreement with the experimental data. To validate the pump results, a comparison was made between the numerical outputs and the performance curves of pump EN 125-315 of Pumpiran Company under relatively similar conditions. The results of this comparison showed that the error of simulation of pump head, consumption power and efficiency values compared with experimental data were about 12, 5.5 and 16 percent, respectively.

Discusses the boundaries of theoretical abstraction or the content of appropriate scientific analysis given the practical intent to design economic changes. Difference between engineering design and economic design; Emphasis on abstraction from politics; Information on the Seven Year Plan.

Research can be defined as a process of translation, or reproduction in which a communicable model or representation of the subject of research is the goal. In applied research, the goal is to formulate a statement which represents the operations necessary to bring about some desired result. What makes such research different from engineering design is the degree of certainty and completeness with which the model can be formulated at the beginning of the project. The means of achieving the desired result are represented in a network of hypotheses of greater or less probability. Some steps can be specified with near certainty, but others remain vague and uncertain until more information about the physical processes involved can be acquired. When the model attains certainty, and all operations can be specified, the project is completed. The uncertainties are reduced by formulating and testing hypotheses. This process can be described as a cycle of four phases: predicting in the model that a certain operation will produce a desired result; performing the operation; comparing the observed result with the prediction; working out the implications of the finding for the model, and hence for the next step in research. This cycle makes research a self-corrective activity. Despite its tentative nature, the model provides the research worker with criteria by which he can evaluate his progress at every step. Incorrect predictions are revealed, and dictate changes in the model.

In this analysis, a measure is developed for the capability of aircraft structures to withstand chance failure, as contrasted to fatigue failure, over the design life of any aircraft system. The measure developed is similar to that for reliability, except the failure rate is specified completely in terms of the power spectral properties of the structural response to the environment. This relation of the reliability to the power spectral parameters enables the reliability of a structure to be predicted. For a given environment and reliability requirement, the analysis could also be used as a basis for determining optimal structural designs. [ABSTRACT FROM AUTHOR]

Since engineering designs generally involve a number of elements about which only partial information is available, design optimization should be conducted under conditions of risk. Utility is nonlinear with cost or revenue; consequently, the enterprise's view of risk is considered through utilities assigned to costs or revenues which deviate from the mean. This is termed "risk programming" to distinguish it from previous contributions in this area. General forms of the objective function, yielding expected utility, are derived for utility functions of two types. When the total cost distribution is normal, an exact solution requiring only a knowledge of expected total cost and the cost variance is obtained. For nonnormal cost distributions, an upper bound of the objective function, requiring knowledge only of the same two quantities, is obtained. A model for engineering design, which provides both the expected total cost and cost variance, is developed based upon division of the elements of variability into several categories. With this division, a reasonable computational procedure is possible. The procedure has been incorporated into a modified direct search optimization program capable of solving large-size design problems. [ABSTRACT FROM AUTHOR]

Selected aspects of a heuristic programming study of the design behavior of a practicing mechanical engineer are described. The study documents the tremendous influence that personality and social variables exert on the technical practice of engineering design. The study bears testimony to Churchman's inseparability thesis [5], i.e., that without our developing some sophisticated notion of what the "system" as a whole is like, the components or subsystems of a system can only be identified and studied with difficulty. The conclusion of the study is that, contrary to most theories of the engineering design process, the behavioral and technical aspects of design are highly inseparable. In certain instances, the influence of behavioral factors on design outweighs the technical factors. [ABSTRACT FROM AUTHOR]

The article discusses the developments in the U.S. Atomic Energy Commission's (AEC) reactor development program. One development is the selection of Bechel Corp. of San Francisco, California by the AEC Idaho Operations Office to perform major construction work on the first reactor to be built at the Commission's new Nuclear Reactor Testing Station near Arco, Idaho. Second is determination of location for the proposed materials testing reactor at the Idaho reactor testing station. The proposal has been completed by the Argonne National Laboratory of Chicago, Illinois. The engineering design work on the reactor is planned for construction at the site of the Knolls Atomic Power Laboratory to produce significant amounts of electric power using neutrons in immediate energy range.

Recently, a method for multi-exposure images fusion based on structural decomposition of images into three parts including signal strength, signal structure and signal mean has been introduced. In this paper, we seek to use this decomposition, for images fusion in other fields, including multimodal medical, multi-focus, and infrared and visible images. To increase the fusion quality, besides the introduction of the proposed weighting factor in the structural decomposition, contourlet transformation and the pyramidal structure have also been used. First, each of the K input images are represented into low frequency and high frequency subbands, by using contourlet transform. Then, all the corresponding subbands (resulting from the same scales and directions) are fused with each other, separately and in an iterative process. In this iterative process, first, a separate pyramid structure (including approximation and detail layers) is created for each of the corresponding K subbands. These layers are obtained by the down-sampling of subbands and structural separation based on the proposed new weighting factor. Then, the fusion is performed in the reverse direction of the pyramidal structure and the fused image of the K corresponding subband is obtained. By repeating this process, the fused image will be obtained for all the corresponding subbands. At the end, the final fused image is obtained by the inverse contourlet transformation on the fused images of the subbands. Several visual and quantitative comparisons, with 7 common methods in this field, have been made. In the visual aspect, the proposed method shows the highest quality.