Malan, NT, Van Der Merwe, JS, Huisman, HW, Kruger, A, Eloff, FC, Pretorius, PJ & Laubscher, PJ 1992, 'A comparison of cardiovascular reactivity of rural blacks, urban blacks and whites', Stress Medicine, vol. 8, no. 4, pp. 241-246.
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AbstractUrbanization is a worldwide phenomenon and is most often accompanied by an increased prevalence of western‐type diseases like hypertension. The higher cardiovascular reactivity (CVR) of black people compared to white people during passive coping stressors has often been linked to their greater vulnerability to hypertension. Blacks, however, display a lower CVR than whites during active coping stressors. In this study it was found that urban blacks show a higher CVR than whites during a passive coping stressor and a lower CVR than whites during an active coping stressor. However, rural blacks consistently show much higher CVR than either whites or urban blacks during both active and passive coping stressors. It seems that CVR is not only a function of the type of stressor applied but can be altered significantly by environmental factors like those experienced during urbanization.
MURTHY, V & WALDRON, KJ 1992, 'POSITION KINEMATICS OF THE GENERALIZED LOBSTER ARM AND ITS SERIES-PARALLEL DUAL', JOURNAL OF MECHANICAL DESIGN, vol. 114, no. 3, pp. 406-413.
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The generalized lobster arm is a six revolute open kinematic chain with 3 consecutive intersecting pairs of axes. A new solution of the inverse position kinematics problem of this arm which takes advantage of its specific geometry is presented. A compari
Venkataraman, SC, Kinzel, GL & Waldron, KJ 1970, 'Optimal synthesis of four-bar linkages for four-position rigid-body guidance with selective tolerance specifications', American Society of Mechanical Engineers, Design Engineering Division (Publication) DE, pp. 651-659.
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In practical rigid-body guidance problems, very often one or more of the design positions need not be generated exactly. Further, extreme accuracy at the design positions is somewhat pointless considering the inherent limitations in linkage manufacturing processes. This emphasizes the requirement of synthesis techniques to be able to handle tolerance specifications on the nominal design positions. A favorable offshoot of the tolerance incorporation would be the accompanying increase in the solution space of the synthesis problem thereby yielding better linkage solutions.
