Volume 1 Issue 1
Authors: Ting-Yu Chueh; Shu-Lung Wang
Abstract: This study discussed the rotary ultrasonic machining (RUM) parameters and tool geometry parameters of optimized hole wall quality, and obtained better and uniformly distributed surface roughness of deep hole walls. The experimental configuration of this study was planned using Taguchi orthogonal array, where the hole diameter, spindle speed, feed rate and power were taken as the experimental factors. Drilling machining experiment was carried out using the parameter combination configured by the experimental design, and wall surface roughness of the drilled holes was measured. A relation model between the average surface roughness and standard deviation of the hole walls and processing parameters and tool geometry were established, so as to achieve optimized surface roughness of the overall deep hole walls. The optimization process respectively aimed at the minimum surface roughness and maximum metal removal rate. The experimental results proved that application of the optimized parameter combination in rotary ultrasonic machining of hole processing can obtain better and more uniform hole wall surface quality.The effect of control factors on the hole quality was discussed from the respects of the straightness deviation, minimum surface roughness and maximum metal removal rate of related factors on the hole when the Taguchi method was applied to rotary ultrasonic machining of hole drilling. The results showed that the level of straightness factors of produced holes can be fully presented.
Keywords: Advanced Ceramics; Rotary Ultrasonic Machining; Surface Roughness; Material Removal Rate; Holes Deviation; Taguchi Method
Authors: Katarzyna Kordas; Elena I. Queirolo; Graciela Ardoino; Daniela Ciccariello; Mercedes Perez; María Sicardi; Nelly Mañay; Jimena Deana
Abstract: Micronutrient deficiencies and environmental toxicants have been shown to contribute to children’s neuro-developmental deficits. Despite intense research on anemia and lead exposure, we know little about how these two factors together affect children’s development. The objective of this study was to test the association of hemoglobin (Hb) and blood lead (BLL) concentrations with measures of development in preschool child-ren (n=69, ages 14.4 – 45.6 mo) from Montevideo, Uruguay. Children were assessed with Bayley Scales of Infant Develop-ment III (Bayley); maternal IQ, depressive symptoms and pa-renting stress were assessed as contextual factors. The mean BLL was 6.0 ± 3.0 µg/dL and 11.5% of children had levels ≥ 10µg/dL. The mean Hb was 12.3 ± 1.7 g/dL and 18.8% of children expe-rienced anemia (Hb <11 g/dL). Mean composite Bayley cognitive, language and motor scores were: 90.3 ± 12.4, 90.1 ± 17.4 and 96.4 ± 14.6 points, respectively. In unadjusted regressions, higher Hb was associated with higher cognitive, language and fine motor scores (point estimates: 0.4 – 0.6, p<0.05). BLL was not asso-ciated with scores. Covariate adjustment slightly attenuated estimates for Hb (p<0.1). There was an Hb-BLL interaction on fine motor scores (p<0.15): Hb was positively associated with performance but only for children with BLL <5 µg/dL. We found an association between Hb and Bayley scores, and a suggestion of an interaction between Hb and BLL. But based on the obtained data we were unable to conclude whether children with anemia are more susceptible to the toxic effects of lead.
Keywords: Lead; Hemoglobin; Preschool; Cognition; Uruguay
Authors: Matjaz Mulej; Tatjana Mlakar
Abstract: Systems science, mostly, supports synthesis and integration through a holism approach for human work and (requisite) wholeness of work’s outcome. Among many systems theories, the Living Systems (LST) and the Dialectical Systems Theories (DST) are equally old. If both a quite holistic insight and creativity are needed, a combination of the LST and the DST is a better choice than using each of them separately. LST can expose many details, while DST can support an innovative action that is needed in a way out of the current global socioeconomicc crisis. LST alone can hardly provide an action, especially one of a creative orientation. DTS alone can hardly provide all the necessary insight, but it can provide a bridge between different aspects of the process at stake and help them generate creative synergies of different professions’ insights. A case of combining both LST and DST in studying public health care proves to be fruitful. DTS can influence people to use LST and its insight in a creative way. The social responsibility reflects principles of DTS (interdependence and holistic approach) explicitly and supports informally the systemic behavior to contribute to sustainable development in the public medical care too.
Keywords: Dialectical Systems Theory; Living Systems Theory-Medical Care; Slovenia; Social Responsibility