New test method to evaluate the impact behaviour of biaxially confined concrete

A new experimental technique for imposing uniaxial or biaxial confinement on specimens subjected to dynamic load has been developed. A drop weight impact machine was used to “split” the confined specimens. Different levels of pre-stress were chosen to evaluate the change in the impact behaviour due to the confinement. The results showed that the variations in the impact energy and in the maximum impact load due to the confinement were small. To quantify the damage of the impacted specimens, a splitting tension test was performed on the already impacted specimens under quasi-static loading conditions. The values of the residual splitting tensile strength showed that the damage depends on the level of confinement. The use of such a testing method may lead to a better understanding of the impact behaviour of cementitious materials.     

Social Crisis.

I am bewildered at the fact that the pages of the American Psychologist reflect almost no awareness of the tragic social upheaval which is accompanying the efforts of the American Negro to win his political, economic, and no less important, his psychological integration with the remainder of American society. This crisis will not disappear because we ignore it. It will be resolved one way or another. The Negro has apparently turned his face from acceptance of his unhappy circumstances and is determined to fight for his human and Constitutional rights. I think it is time that we, as a profession, give recognition to what is occurring around us, that we discuss what our role can and should be, and that each of us, in our own communities volunteer our services and our knowledge to work towards a just and peaceful integration of the American Negro into the American society of the twentieth century. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Human factors and folk models

This paper presents a discussion of the susceptibility of human factors to the use of folk models. The case of automation-induced complacency is used as a guiding example to illustrate how folk models (1) substitute one label for another rather than decomposing a large construct into more measurable specifics; (2) are immune to falsification and so resist the most important scientific quality check; and (3) easily get overgeneralised to situations they were never meant to speak about. We then discuss the link between models and measurements, where the model constrains what can be measured by describing what is essential performance, and where the models parameters become the basis for specifying the measurements. We propose that one way forward for human factors is to de-emphasize the focus on inferred and uncertain states of the mind, and shift to characteristics of human performance instead.     

"On being sane in insane places": A comment from England.

Comments on 3 aspects of D. L. Rosenhan's (see record 1973-21600-001) report on simulated schizophrenia. First, psychiatric diagnosis, particularly of schizophrenia, is culture bound rather than absolute and depends on the interaction between the symptoms presented by a patient (or pseudopatient) and the background and training of the psychiatrist. Diagnostic errors will decrease as criteria for schizophrenia become more clearly defined and universally accepted. Second, the ethics of research using pseudopatients is questioned. Widespread use of simulation may bring research itself into disrepute. Third, as psychiatric hospitals become more oriented toward the therapeutic community, continuous patient assessment and monitoring become possible through increased informal contact with the staff. Diagnostic errors are thus less likely to occur. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Synergistic science

Should computational materials science be recognized as a field with a role in the community comparable to computational physics or chemistry? With the emergence of multiscale modelling, the answer is a resounding 'yes'.