Form and Dimension

In this case the designer has freedom of choice of both form and dimension as well as in the selection of the materials. Given this freedom, it would be desirable to examine several of the alternatives to see which would provide the best seating at the lowest cost. Obviously, there is no point in doing all of the possibilities so a selection should be made on the basis of anticipated use as well as style requirements. Three types will be analyzed. They are the single curve sheet cantilever mounted from the back, the molded pan supported on four legs, and the structural foam molding which is front supported. 

In order to simplify the analytical exercise, a particular material was selected for each. The single curved sheet is made of TS polyester fiber glass molded to the shape. The corner supported pan is molded from ABS plastics. The structural foam unit is molded from PP with glass fiber filler. 

From inspection of the three designs it is apparent that the main stress of the loading will be at the support point for the seat. This will be assumed to be sufficiently strengthened to prevent failure, either by excessive stress or bending at the support point. The analysis will be concerned with the fact that the seat itself will not break as a result of the load and will not sag excessively after continued use. For this example the impulse load caused by dropping into a chair will be ignored. 

In each case the section is designed to keep the deflection to less than 2 in. in 16 in. for a design life of 5 years and the extreme fiber stress is kept to a value less than the yield strength of the material. The first step in the analysis is to determine the necessary section to resist the bending load using the short-term tensile and compressive strength and modulus values. The extreme fiber stress is calculated for these sections to determine that the chair will not break when deflected. 

A time dependent modulus is then calculated using the extreme fiber stress level for each of the materials at the initial stress value level using the loading-time curve developed. If the deflection at the desired life is excessive, the section is increased in size and the deflection recalculated. By iteration the second can be made such that the creep and load deflection is equal to the maximum allowed at the design life of the chair. This calculation can be programmed for a computer solution. 

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Hydrostatic pressing and isostatic pressing are usually applied to expis that have been evacuated, frequently at elevated temps. Temps up to 130° and pressures up to 30000 psi have been used. The surfaces where pressure is applied thru elastic membranes are, of course, of relatively poorly defined form and dimensions. Hence, these pressing processes must almost invariably be followed by machining... 

A table of physical forms and dimensions of cypical US propellant grains is given at the end of this volume (Table IX)... 

The effect of various factors—the forms and dimensions of the igniting surface, motion of the fuel, etc.—are reduced to their effect on the conditions of heat transfer. 

Raw rubber is in masses or cakes of form and dimensions varying with the quality and origin, often of stratified section and not rarely containing impurities or occluded extraneous bodies it varies in colour from yellowish to brown and has a more or less marked empyreumatic odour D 0-91-0 97 it is highly elastic, but loses its elasticity when cooled to o° or heated to 6o° at about ioo° it begins to soften and it melts at about 180 0 to a blackish liquid, which becomes pasty on cooling but solidifies only after a very long time. 

For a natural stream, the solution is not so direct, because the form and dimensions of a cross section cannot be assumed and then the distance to its location computed. As there exist various slopes and cross sections at different distances upstream, the value of L in Eq. (10.123) must be assumed and then the depth of stream at this section can be computed by trial. 

One of the prominent features of polymeric liquids is the property to recover partially the pre-deformation state. Such behaviour is analogous to a rubber band snapping back when released after stretching. This is a consequence of the relaxation of macromolecular coils in the system every deformed macro-molecular coil tends to recover its pre-deformed equilibrium form. In the considered theory, the form and dimensions of the deformed macromolecular coil are connected with the internal variables which have to be considered when the tensor of recoverable strain is to be calculated. Further on, we shall consider the simplest case, when the form and dimensions of macromolecular coils are determined by the only internal tensor. In this case, the behaviour of the polymer liquid is considered to describe by one of the constitutive equations (9.48)-(9.49) or (9.58). 

FIGURE 20.5 Standard lap shear test specimen design (a) form and dimension of lap shear specimen (b) standard test panel of five lap shear specimens. (From ASTM D 1002.)... 

Addition of one or both of the corresponding homopolymers to a block copolymer offers further possibilities for constructing morphologies of specified form and dimensions. A first consideration in this area is the case for which the homopolymers have molecular weights which are equal to or less than the molecular weights of the corresponding block segments in the copolymer, i.e. g and... 

Raw materials are delivered to manufacturing facilities in containers of different nature, form and dimensions and there may be many of them in one batch. Steps should therefore be taken to take a sufficient number of primary samples in order to make sure of the quality and homogeneity of the batch received. Various appropriate utensils which can provide representative samples may be employed. The type of utensil and protocol to be used is that judged to be the most suitably adapted to the particular problem. 

Products made by primary shaping whose forms and dimensions are essentially similar to those of the finished components (e.g., machine parts) or final products. The shape of these products corresponds to the product s purpose to the maximum extent. Obtaining the desired final form as well as final dimensions mostly requires only a few, as a rule chipping, operations to be carried out at functional surfaces. 

The volume of plastic remains unchanged, but the form and dimensions are changed completely. 

Through a synthesis process the concept is developed into a distinct embodiment, which incorporates specific product form and dimensions. This detailed description is required for the analysis process, which predicts product... 

Summarizing, the process consists in forcing a conductive ink to pass through a screen which is placed on a material that acts as support. The screen only allows the pass across a few pores that define the form and dimensions wished for the electrode, staying hereby an image of the same one printed on the support. 

Are forged from hardened and tempered high-tensile steel and are rated according to their SWL A range of types are available including those with a safety latch as shown in Fig. 19.10. Form and dimensions are set out in BS EN 1677-5 which states that all hooks shall be free from patent defect and shall be cleanly forged in one piece. After manufacture and heat treatment each hook shall be subjected to a proof load. After proof testing each hook is stamped to allow identification with the manufacturer s certificate of test and examination. 

The important point in this equilibrium of potential determining ions is that by its existence the total potential difference in the double layer is completely determined, and consequently, in all problems of colloid chemistry, we have to consider the potential of the double layer as a given quantity, to be influenced only by the concentration of one species of ions. The charge and structure of the double layer adapt themselves to the variable properties of the system, such as concentration of indifferent (non-potential determining) electrolytes, dimensions and specific adsorption of the counter ions, form and dimensions of the particles, etc. 

B. B. Mandelbrot, Fractals, Form and Dimension (San Francisco, Freeman (1977)). 

The final growth forms and dimensions of the crystals were different for systems I and n. The ternary phases containing Zn grew in the form of hexagonal plates, in which the (0001) face appeared repeatedly, whereas single crystals of the Cd system had well-developed octahedral shapes and repeated (111) faces. 

One way to estimate the influence of transport processes is to use directly experimental results observed under given experimental conditions. In general, the experimentalist has information concerning observed reaction rates, bulk reactant concentrations, and temperature, as well as the catalyst pellet form and dimensions. With these details at hand, the Weisz module can be estimated. For example, for spherical catalytic particles, see Equation 2.180. 

The course and time of the drying process depend on the drying conditions, on the temperature and moisture profiles developed during the drying process, and above all, on the moisture movement in the product. Moisture movement is governed by the properties, form and dimension of the product, and the type of moisture bond in the product. Some relationships are listed in 1h-ble 5-2 to describe different mechanisms of moisture movement. 

SMITH D M, IRWIN s J and MANN D (2009) Optimising the physical form and dimensions of feed pellets for tropical spiny lobsters, in WiUims K C (ed.). Spiny Lobster Aquaculture in the Asia-Pacific Region. Canberra ACIAR, 157-162. 

A washing-up machine is used to clean all utensils (implements and parts of preparation apparatus) which have such a form and dimension that they fit into the washing-up machine and can be placed in such a way that all surfaces will be reached by the detergent solution during the washing process. Additionally the utensils must be resistant to the treatment, the cleaning temperature and the used detergents. 

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