Summary Remarks

The strength of special classes of laminated fiber-reinforced composite materials has been analyzed on the basis of several hypotheses  

For cross-ply laminates, a knee in the load-deformation cun/e occurs after the mechanical and thermal interactions between layers uncouple because of failure (which might be only degradation, not necessarily fracture) of a lamina. The mechanical interactions are caused by Poisson effects and/or shear-extension coupling. The thermal interactions are caused by different coefficients of thermal expansion in different layers because of different angular orientations of the layers (even though the orthotropic materials in each lamina are the same). The interactions are disrupted if the layers in a laminate separate. 

For angle-ply laminates, no such knee or change in slope occurs in the load-deformation behavior. Simultaneous failure (fracture) of all layers occurs. 

For two- and three-layered cross-ply and angle-ply laminates of E-glass-epoxy, Tsai [4-10] tabulates all the stiffnesses, inverse stiffnesses, thermal forces and moments, etc. Results are obtained for various cross-ply ratios and lamination angles, as appropriate, from a short computer program that could be used for other materials. 

9 MODEL HAMILTONIANS BEYOND THE LEVEL OF SPIN EXCHANGE 

There are cases when a model Hamiltonian including only spin exchange interactions is not adequate in describing magnetic systems. In such cases, a model Hamiltonian is improved by adding other energy terms, as can be seen from equations 24.14a and (24.63). The spin Hamiltonian of equation 24.63 depends only on the relative 

As can be seen from the equation 24.71, one can make the model Hamiltonian quite complex. In general, use of an elaborate model Hamiltonian is undesirable and is not warranted because the objective of using a model Hamiltonian is to describe the essence of the chemistry/physics involved with a minimal number of parameters. Nevertheless, it is important to understand what each term of the model Hamiltonian stands for. 

The literature on magnetic studies shows many examples in which the magnetic properties of a system were interpreted with a spin lattice irrelevant for the system largely because the selection of spin lattice relies on the geometrical pattern of 

The spin sites I and 2 below are related to each other by inversion symmetry /. If the spin of site I has the orientation depicted, what should be the orientation of the spin at site 2  

A cogent question is whether or not the vehicle safety standards produced any safety gains. The claim that any change in the fatality rate must be due to safety policy is shown to be absurd. Instead, the comprehensive studies which estimate the safety impacts of the set of standards on fatality rates were reviewed and compared to the original predictions based on the technological approach. Most of the later studies are bottom-line analysis which employ some variant of the individual net benefit approach. The following conclusions are drawn  

Five criteria for jud g the analytical acceptability of ex ante evaluation of a proposed safety standard for administrative and legal dedsions  

The current Dole Rule on passive restraints only partly satisfies these items on the acceptability check list. 

Just as imperfections can be foimd in the traffic safety decisions of individual motorists so too can imperfections be found in the formulation and implementation of traffic safety policy. Imperfections are due to misperceptions about trivial costs of safety standards and unlimited public 

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The discussion of materials selection factors is naturally divided into three parts (1) overall factors pertinent to selection of the composite material itself, (2) factors governing the selection of the fibers, and (3) factors essential to selection of the matrix system. Those three types of selection trade-offs will be described, followed by summary remarks on the process of selecting a suitable composite material. 

Studies of proteolytic fragments of staphylococcal nuclease (Tan-iuchi and Anfinsen, 1969) and RNase A (Taniuchi, 1970) seemed to support this view. Taniuchi (1970), in summary remarks, said Thus, the minimum information of the specific folding of a protein requiring almost the entire amino acid sequence is observed with both staph-yloccocal nuclease and bovine pancreatic ribonuclease. ... 

Cloud, P.E, Jr., 1965b. Symposium on the evolution of the Earth s atmosphere. Chairman s. summary remarks. Proc. Natl, Acad. Sci. USA, 53 1169-1172. 

Monoterpenes are appreciably volatile and are produced in substantial quantities by a range of higher plants and trees. Only some summary remarks are given here. 

The Lettering of the references of these Summary Remarks follows that of the Abstract book of the Conference. These references correspond to the papers presented here. ... 

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