What Is Design

THE DETERMINATION OF THE BEHAVIORAL RESPONSE EXHIBITED BY A PARTICULAR STRUCTURAL CONFIGURATION UNDER SPECIFIC LOADS (WHAT LOAD DOES THE STRUCTURE TAKE ) 

THE PROCESS OF ALTERING DIMENSIONS, SHAPES, AND MATERIALS TO FIND THE BEST (OPTIMUM) STRUCTURAL CONFIGURATION TO CARRY SPECIFIC LOADS AND PERFORM SPECIFIC TASKS (WHAT IS THE BEST STRUCTURE TO TAKE THE LOAD ) 

The key to a rational design process is establishing a set of mechanistic relationships that relate the configuration to its performance. Use of those mechanistic relationships is what distinguishes the structural designer from a dress designer. 

As an example of the contrast between analysis and design, consider the column buckling problem. To analyze the buckling resistance of a simply supported, axially loaded column, we use the Euler-Bernoulli equation, 

However, four different moments of inertia for each of the four different materials (hence different moduli of elasticity) are obtained from Equation (7.2). Moreover, knowing the moment of inertia of a column does not teli us the shape or dimensions of a column We usually select a column 

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PM causes its health effects, especially its effect on cardiovascular health, are unclear there is some evidence that chemical composition of PM is not as important as particle size, with the greatest risks associated with what is designated as PM 2.5 (particle size less than 2.5 pm). Some experimental evidence suggests (but does not establish) that so-called fine (0.25 to 1.0 pm) and ultrafine (<0.25 pm) are the most potent toxicants, but regulation is now focused on PM 2.5. Regulation of PM and the primary air pollutants is highly contentious, because the costs of controlling them are enormous. 

The valleys V between the atoms of a catalyst, dealt with in the multiplet theory, corresponds to what is designed in a number of studies by means of free valencies or by asterisks 49, 50)... 

So, what is design control It is a systematic process with a range of activities, including the following nine key elements ... 

A simple conception of the notion of exact differential can be obtained from the following down-to-earth example In a hilly terrain, two points (1) and (2) are delimited. A variable h[x,y) denoting the height level of the terrain as a function of the xy coordinate is analogous to what is designated a state variable in thermodynamics. The differential dh x, y) is an exact differential because it is evident that... 

This section is divided into two sections the first concerned with time-dependent methods for describing the evolution of wavepackets and the second concerned with time-independent methods for solving the time independent Sclirodinger equation. The methods described are designed to be representative of what is in use. 

HyperChem should not be viewed as a black box that computes only what its designers thought correct. It has an open architecture that makes it possible to customize it many ways. As far as is possible, the parameters of molecular mechanics and semi-empirical calculations are in the user s hands. As the techniques of software engineering advance and our expertise in building new... 

What is significant about these reactions is that only two possibilities exist addition with the same configuration (D -> DD or L LL) or addition with th< opposite configuration (D DL or L LD). We shall designate these isotactic (subscript i) or syndiotactic (subscript s) additions, respectively, and shal define the rate constants for the two steps kj and k. Therefore the rates o isotactic and syndiotactic propagation become... 

A more recent concept which could have significant impact on future designs is that of inherent safety (12). This basic principle states that what is not there cannot be blown up or leak into the environment. Thus, the idea is to avoid the hazard in the first place. 

C. Daniel, App/ications of Statistics to lndustria/Experimentation, ]oE Wiley Sons, Inc., New York, 1976. This book is based on the personal experiences and insights of the author, an eminent practitioner of industrial appHcations of experimental design. It provides extensive discussions and concepts, especially in the areas of factorial and fractional factorial designs. "The book should be of use to experimenters who have some knowledge of elementary statistics and to statisticians who want simple explanations, detailed examples, and a documentation of the variety of outcomes that may be encountered." Some of the unusual features are chapters on "Sequences of fractional repHcates" and "Trend-robust plans," and sections entided, "What is the answer (what is the question )," and "Conclusions and apologies."... 

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