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The main objective of research work to investigates the effects of various process parameters on the material removal rate, kerf width, surface roughness and the dimensional accuracy of Inconel 718 workpiece subjected to wire electrical discharge machining (WEDM). The input parameters of this study were wire speed, wire tension and flushing rate. The individual as well as interacting effect of process parameters on surface roughness, kerf width and dimensional accuracy. It was found that, in order to minimize the diameter error for circular cuts, the flushing rate, wire speed and wire tension should all be held at maximum values. The wire tension and wire speed both exhibited an insignificant effect on the surface roughness. The dimensional accuracy of the machined holes decreased with increasing wire tension and in order to achieve maximum material removal rate, wire tension and wire speed must be around 1400–1600 gf and at 8 m/min respectively. The flushing rates over 5 L/min had a negligible effect on the material removal rate. The highest kerf width and material removal rate were obtained at medium values of wire tension (1400–1600 gf) and wire speed (8 m/min). The lowest diameter error is achieved in a combination of maximum flushing rate, wire speed and wire tension. Factors such as circularity, cylindricity and hole diameter were closely examined in order to gain a deeper understanding of their influence on dimensional accuracy. [ABSTRACT FROM AUTHOR]

This paper attempts to develop a novel insight into Hannah Arendt’s socio-political theories in order to examine and alleviate the socio-spatial exclusion of the vulnerable by greater society. It utilises Arendt’s classification of the terms ‘communal’ and ‘irrelevant’ as a pair of opposing concepts in which the state of ‘vulnerability’ is associated with being deemed to be ‘irrelevant’ within society. The study addresses the exclusionary qualities of public spaces by focusing on the complex relationships observed between these concepts in Turkey through a content analysis of 35 national satire magazines and 30 YouTube channels that reflect on various states and perceptions of vulnerability in Turkish society and culture. It concludes with a series of recommendations by which to close the gap within the communal-irrelevant duality that could enhance vulnerable individuals’ urban rights.

Effect of abrasive particle size on tribological behaviour of different elastomers was investigated experimentally in this study. The size of abrasive particle size was varied from coarse (425 µm) to fine (82 µm). Wear rate and coefficient of friction were calculated and analyzed accordingly followed by the examination of worn surfaces by a scanning electron microscope to unravel the wear mechanism. Experimental results showed that abrasive size had a significant effect on wear and friction behaviour of the elastomers. As the abrasive particle size increased, wear rate and coefficient of friction also increased at different rates and exhibited different wear mechanisms that changed from friction to fatigue and roll formation. Mechanical properties of elastomers such as hardness, tensile strength, tear strength, and elongation at break also contributed to wear and friction. The effect of elongation at break and tensile strength on wear rate is more pronounced at lower abrasive particle size, whereas hardness and tear strength play a pivotal role at the higher abrasive size. [ABSTRACT FROM AUTHOR]

Bu çalışmada modern toplum ve teknoloji eleştirisi yapan aynı zamanda her bölümünde farklı bir konuyu işleyen Black Mirror dizisinin Hated In The Nation (Sosyal Linç) bölümü örneklemi incelenmiştir. Dizi bölümü, dizide yer alan teknolojik ögeler bağlamında, teknolojiye ilişkin eleştiriler üzerinden ve yöntem olarak Ferdinand de Saussure’un göstergebilimsel yöntemi ve Roland Barthes’ın anlamlandırma yöntemi ile incelenmiştir. Çalışmada, örneklem içerisinde anlatılan teknolojiler ve teknolojik gelişmeler, topluma ve insanlığa faydalı mıdır? İnsan eylemleri üzerinde ne gibi etkiler yaratmaktadır? sorunsalına cevap aranmıştır. Genel olarak analizde teknoloji ve teknolojik gelişmeler ile birlikte sosyal medya hesapları insanların sürekli bir gözetim mekanizması ile çevrelendiği, mahremiyetlerinin yok sayıldığı dahası teknolojinin insanlara faydadan çok zarar getirdiği gözlenmiş ve insanların ötekileştirildiği, yalnızlaştırıldığı, ifşa edildiği, hedef gösterildiği sonuçlarına varılmıştır.

Water meters of different types and sizes are used to monitor and bill the water supply. Although the water is of drinking water quality, its chemo-physical properties often adversely affect the measuring behaviour of a meter after a while. There is thus the risk that they no longer meet legal requirements and may no longer be used. In this paper a test regime with a focus on pH, total hardness and particle load is presented which allows water meters to be tested closer to their operating conditions prior to placing them on the market. The regime goes beyond the conventional continuous durability test as described in OIML R49:2013(E) and ISO 4064:2014. The feasibility and reliability of the test regime has been demonstrated through implementation at different facilities. In the study, the measurement performance of water meters of various types and from different manufacturers was also investigated. A heterogeneous spread of measurement errors was found for both, water meters in mint conditions and those which were exposed to a defined water quality. Furthermore, compared to the conventional continuous durability test, the test regime developed in the study generally leads to stronger changes in the measurement error of the water meters. HIGHLIGHTS Test derived to assess performance of water meters closer to their operating conditions.; Mixing recipes for test waters of different quality developed to ensure comparability.; Error curves of the water meters depend on the combination of meter type and manufacturer.; Trend to less effects on electronic water meters.; Comparison carried out to tests with tap water tendency to larger water quality-related effects in the error curves.;