Hard turning is a machining process that is widely used in the precision mechanical industry. The characterization of the functional surface texture by the ISO 13565 standard holds a key role in automotive mechanics. Until now, the impact of cutting conditions during hard turning operation on the bearing area curve parameters has not been studied (ISO 13565). The three parameters Rpk , Rk and Rvk illustrate the ability of the surface texture to resist friction. In this work, the main objective is to study the impact of cutting conditions (Vc, f and ap) of the hard turning on three parameters of the bearing area curve. The statistical study based on response surface methodology (RSM), analysis of variance (ANOVA) and quadratic regression were performed to model the three output parameters and optimize the input parameters. The experimental design used in this study is the Taguchi L25 orthogonal array. The results obtained show that the cutting speed has a greater effect on the bearing ratio curve (Rpk , Rk and Rvk ) parameters with a percentage contribution of 37.68%, 37.65% and 36.91%, respectively. The second significant parameter is the feed rate and the other parameter is significant only in relation to Rpk and Rk parameters.
Natural fiber polymer composites are gaining focus as low cost and light weight composite material due to the availability and ecofriendly nature of the natural fiber. Fiber composites are widely used in civil engineering, marine and aerospace industries where dynamic loads and environmental loads persist. Dynamic analysis of these composites under different loading and environmental conditions is essential before their usage. The present study focuses on the dynamic behavior of areca nut husk reinforced epoxy composites under different loading frequencies (5 Hz, 10 Hz and 15 Hz) and different temperatures (ranging from 28ºC to 120ºC). The effect of loading and temperature on storage modulus, loss modulus and glass transition temperature was analyzed. Increase in storage modulus is observed with increase in loading frequency. The storage modulus decreases with increase in temperature. The glass transition temperature of the composite is determined to be 105ºC. The elastic modulus calculated from the DMA data is compared with three point bending test.
Olga Tokarczuk is among the pioneers exploring a certain turn towards emotions, artistic efforts that value sensation over thought.
Elusive phenomena such as the parental care habits of prehistoric animals would seem to be forever inaccessible to paleontological research. However, new spectacular finds offer some deeper insight into such behavior.
On the question when mammals first started to rear their offspring, the jury is still out. Was such care-giving behavior actually inherited from our reptilian ancestors?
Astronomers are charting out a radio map of the sky, showing hundreds of thousands of previously unknown galaxies.
For many years, people’s perceptions of wolves had nothing to do with actual knowledge about wolf biology and ecology. What can close observations of wolf families teach us about these mammals? Should we give wolves names? And why don’t they need our empathy?
Marta Wrzosek from the Faculty of Biology, University of Warsaw talks about the fascinating and complex world of fungi and examines the complicated role of language in science popularization.
What does it take to secure a foothold in the global high-tech market and keep such a business afloat? We can look at the experiences of other companies to find proven solutions and answers to the most important questions.
The word “sensitivity” has many meanings, ranging from more mundane technical senses, to meanings specific to statistics and machine learning, all the way to the most human understanding of the concept – that of tender emotions.
On the shift toward tender sensitivity – the role of relations, emotions, and empathy in design.
Metaphysical tenderness does exist – it lies at the core of joyful acceptance of all manifestations of life on both sides of our skin and determines our zest for life, perhaps to a greater extent than money, fame, or origin.
Painter and graphic designer Rafał Olbiński explains how art motivates us to be better people and why good manners are worth more than laws.
Sensors designed by Polish engineers help detect traces of life beyond Earth. Adam Piotrowski of Vigo System tells us what else these devices can do.
Photography has a special way of bestowing extraordinary meaning on ordinary subjects – we discuss it with Izabela Łapińska from the Leon Schiller National Film School in Łódź.
Blockchain technology may soon profoundly transform the economic, financial, and legal reality of entire societies and even systems of government. But is this new financial instrument (a new form of ”tender,” in the sense of money offered for payment) sensitive only to the rules of free-market economics, or also to human rights and sensibilities? Whose needs will determine the direction of change: those of ordinary people, or the financial elite?
Highly sensitive devices such as the SHRIMP IIe/MC ion microprobe help scientists to make precise measurements of past time-scales, paleoclimatic temperatures, and much more.
Why is the word “tenderness” rarely mentioned in the Bible? Can we make any judgement about God’s tenderness? We talk to Father Tadeusz Dola, Professor Emeritus of Theology and head of the Theological Sciences Committee of the Polish Academy of Sciences.
Psychotherapist and psycho-oncologist Justyna Pronobis-Szczylik talks about the need for tenderness and the insensitivities of the healthcare system.